bluuebunny/crossref_metadata_2025_split huggingface dataset:
Activity following arousal in winter in North American vespertilionid bats
Authors: BOYLES JUSTIN G. , DUNBAR MIRANDA B. , WHITAKER JOHN O. 
Published: December 2006

ABSTRACT

Many bat species hibernate to conserve energy during winter and like all hibernators they commonly arouse. During these arousals, some bats may undertake activities away from the hibernation site. Systematic ecological studies of the frequency and purpose of winter activity in temperate zone bats of North America are rare and much of the literature involves observations of single individuals or unmarked populations.
We review the available literature on winter activity among North American vespertilionid bats to highlight the paucity of data on this subject and to stimulate future research. Due to the lack of repeated, systematic studies on most North American species, the conclusions drawn are general or pertain only to parts of the geographical range of any species.
We suggest that winter activity is ubiquitous among temperate zone bats, but the degree and purpose of activity varies greatly between and within species. In general, cave‐dwelling bats tend to be relatively inactive compared with tree and foliage roosting bats during winter.
Cave‐dwelling and tree cavity‐dwelling species do not appear to feed, but they do drink and occasionally copulate during the hibernation period. Species that hibernate in foliage or leaf litter are the most active species during winter and may feed and drink throughout winter, although they probably do not copulate because of their solitary nature.
We encourage researchers to conduct studies on all aspects of winter activity for North American vespertilionids across wide latitudinal and altitudinal gradients. We suggest studies in the near future be focused on estimating the energetic costs and benefits of winter activity through determination of the frequency and intensity of winter feeding activity and more thorough examinations of movements within and among caves. Studies on common, wide‐ranging species have the potential to illuminate large‐scale patterns and differences and should be favoured over studies on rarer species.
Cyclic di‐GMP signalling in the virulence and environmental adaptation of Xanthomonas campestris
Authors: Ryan Robert P. , Fouhy Yvonne , Lucey Jean F. , Jiang Bo‐Le , He Yong‐Qiang , Feng Jia‐Xun , Tang Ji‐Liang , Dow J. Maxwell 
Published: December 2006

SummaryCyclic di‐GMP is a second messenger with a role in regulation of a range of cellular functions in diverse bacteria including the virulence of pathogens. Cellular levels of cyclic di‐GMP are controlled through synthesis, catalysed by the GGDEF protein domain, and degradation by EAL or HD‐GYP domains. Here we report a comprehensive study of cyclic di‐GMP signalling in bacterial disease in which we examine the contribution of all proteins with GGDEF, EAL or HD‐GYP domains to virulence and virulence factor production in the phytopathogen Xanthomonas campestris pathovar campestris (Xcc). Genes with significant roles in virulence to plants included those encoding proteins whose probable function is in cyclic‐di‐GMP synthesis as well as others (including the HD‐GYP domain regulator RpfG) implicated in cyclic di‐GMP degradation. Furthermore, RpfG controlled expression of a subset of these genes. A partially overlapping set of elements controlled the production of virulence factors in vitro. Other GGDEF‐EAL domain proteins had no effect on virulence factor synthesis but did influence motility. These findings indicate the existence of a regulatory network that may allow Xcc to integrate information from diverse environmental inputs to modulate virulence factor synthesis as well as of cyclic di‐GMP signalling systems dedicated to other specific tasks.
Electrical signals and their physiological significance in plants
Authors: FROMM JÖRG , LAUTNER SILKE 
Published: December 2006

ABSTRACTElectrical excitability and signalling, frequently associated with rapid responses to environmental stimuli, are well known in some algae and higher plants. The presence of electrical signals, such as action potentials (AP), in both animal and plant cells suggested that plant cells, too, make use of ion channels to transmit information over long distances. In the light of rapid progress in plant biology during the past decade, the assumption that electrical signals do not only trigger rapid leaf movements in ‘sensitive’ plants such as Mimosa pudica or Dionaea muscipula, but also physiological processes in ordinary plants proved to be correct. Summarizing recent progress in the field of electrical signalling in plants, the present review will focus on the generation and propagation of various electrical signals, their ways of transmission within the plant body and various physiological effects.
Analyses of barley spike mutant waxes identify alkenes, cyclopropanes and internally branched alkanes with dominating isomers at carbon 9
Authors: von Wettstein‐Knowles Penny 
Published: December 2006

SummaryAbout 15% of the epidermal wax on Hordeum vulgare cv. Bonus barley spikes is n‐alkanes. Longer homologues are greatly reduced in the eceriferum mutants, cer‐a6, cer‐e8, cer‐n26, cer‐n53, cer‐n985, cer‐x60, cer‐yc135 and cer‐yl187. Simultaneously hydrocarbons accounting for only traces in the wild‐type become prominent in the mutants, although their chain‐length distributions remain unchanged. Accordingly several new hydrocarbon series were identified. The two major ones were C23–C35cis monoenoic alkenes (the major 9‐ene isomer was part of a homologous series including 11, 13 and 15‐enes), and the novel C27–C31 cyclopropanes (the ring carbons of major isomers were 9,10 and 11,12 with lesser amounts of 13,14). Three minor series included 2‐ and 3‐methylalkanes plus C25–C33 internally branched alkanes (methyls on carbons 9, 11, 13, 15 or 17; shorter homologues dominated by the 9 isomer, longer homologues by 11, 13 or 15 isomers). Acyl chains destined for spike waxes are synthesized via acyl and polyketide elongase systems plus associated reductive and decarbonylative/decarboxylative enzyme systems. Both elongation systems are defective in synthesizing C32 acyl chains in all nine mutants. The similarities in the position of the chemical groups (primarily on carbon 9, secondarily on carbon 11) of the alkenes, cyclopropanes and internally branched methyl alkanes imply an origin from a common, hitherto unrecognized associated pathway in barley, designated the enoic pathway. The elongation system leading to the enoic derived hydrocarbons differs from the known elongation systems by inclusion of a mechanism for introducing a double bond.
The chloroplast protease subunit ClpP4 is a substrate of the E3 ligase AtCHIP and plays an important role in chloroplast function
Authors: Shen Guoxin , Yan Juqiang , Pasapula Vijaya , Luo Jinhua , He Cixin , Clarke Adrian K. , Zhang Hong 
Published: December 2006

SummaryAnimal CHIP proteins are chaperone‐dependent E3 ubiquitin ligases that physically interact with Hsp70, Hsp90 and proteasome, promoting degradation of a selective group of non‐native or damaged proteins in animal cells. The plant CHIP‐like protein, AtCHIP, also plays important roles in protein turnover metabolism. AtCHIP interacts with a proteolytic subunit, ClpP4, of the chloroplast Clp protease in vivo, and ubiquitylates ClpP4 in vitro. The steady‐state level of ClpP4 is reduced in AtCHIP‐overexpressing plants under high‐intensity light conditions, suggesting that AtCHIP targets ClpP4 for degradation and thereby regulates the Clp proteolytic activity in chloroplasts under certain stress conditions. Overexpression of ClpP4 in Arabidopsis leads to chlorotic phenotypes in transgenic plants, and chloroplast structures in the chlorotic tissues of ClpP4‐overexpressing plants are abnormal and largely devoid of thylakoid membranes, suggesting that ClpP4 plays a critical role in chloroplast structure and function. As AtCHIP is a cytosolic protein that has been shown to play an important role in regulating an essential chloroplast protease, this research provides new insights into the regulatory networks controlling protein turnover catabolism in chloroplasts.
PD‐L1 expression analysis in gastric carcinoma tissue and blocking of tumor‐associated PD‐L1 signaling by two functional monoclonal antibodies
Authors: Sun J. , Xu K. , Wu C , Wang Y , Hu Y , Zhu Y , Chen Y , Shi Q , Yu G , Zhang X 
Published: December 2006

AbstractProgrammed death‐1 ligand‐1 (PD‐L1), a member of the B7 family of costimulatory molecules, plays an important role in the regulations of the cellular and humoral immune responses. In this study, two mouse anti‐human PD‐L1 monoclonal antibodies named 10E10 and 2H11 were successfully generated and further characterized. Monoclonal antibody 10E10 bound to distinct PD‐L1 epitope comparing an available anti‐PD‐L1 monoclonal antibody on a series of malignant cell lines, activated T lymphocytes, B lymphocytes and dendritic cells. Then, by using immunohistochemistry staining with monoclonal antibody 2H11, the expression of PD‐L1 was found in human gastric carcinoma specimens but not in normal or gastric adenoma tissues. Additional data show that PD‐L1 can be regarded as a decisive factor in evaluating gastric carcinoma prognosis and anti‐human PD‐L1 monoclonal antibody 10E10 could inhibit T‐cell apoptosis induced by tumor‐associated PD‐L1. Taken together, these results showed that the two functional mouse anti‐human PD‐L1 monoclonal antibodies we generated might be of great value for further exploration of the costimulatory molecule regulating network and immunointervention for tumor immunotherapy.
The expression analysis of ICOS‐L on activated T cells and immature dendritic cells as well as malignant B cells and Grave’s‐disease‐derived thyroid tissues by two novel mAbs against human ICOS‐L
Authors: Wang F. , Zhu W. , Liu T. , Sun Z. , Ju S. , Ju S. , Yu G. , Xie W. , Deng Z. , Lu B. , Zhang X. 
Published: December 2006

AbstractICOS‐L, a newly identified member of B7 superfamily, plays an important role in immune responses. In this article, we report on two novel mouse anti‐human ICOS‐L monoclonal antibodies (mAbs) named as 11C4 and 12B11, whose specificities were verified by methods of flow cytometry, western blotting, and epitope competition assay. The two mAbs bound to distinct ICOS‐L epitopes on B cells. Interestingly, mAb 11C4 could well recognize ICOS‐L molecule on activated T cells and Jurkat cell lines, which is different from commercial anti‐ICOS‐L mAb (clone number MIH12) and the other mAb 12B11. In addition, we found that the expression of ICOS‐L molecule was only detected on the surface of immature monocyte‐derived dendritic cells (Mo‐DCs) and was sharply decreased after induction of mature Mo‐DCs activated by tumor necrosis factor‐α or CD40. Furthermore, we showed that 11C4 could effectively suppress the maturation of Mo‐DCs in vitro as evidenced by the low expression of CD80, CD86, CD83, and human leukocyte antigen‐DR, which suggested that ICOS‐L may be involved in the maturation of Mo‐DCs. Using immunohistochemistry staining with mAb 11C4, the expression of ICOS‐L was found in B lymphoma tissues and thyroid tissues from the Grave’s disease but not in thyroid adenoma and normal thyroid tissues.
Diagnosis of paracoccidioidomycosis by a dot blot assay using a recombinant Paracoccidioides brasiliensis p27 protein
Authors: Correa M. M. , Bedoya A. M. , Guerrero M. P. , Méndez J. , Restrepo A. , McEwen J. G. 
Published: December 2006

SummaryA variety of immunological methods have proven useful for Paracoccidioidomycosis (PCM) diagnosis; however, they are often time consuming and many lack sensitivity and specificity, partially attributed to the use of crude antigens, which give cross reactivity. Until now, attempts to clone and express Paracoccidioides brasiliensis immunodominant antigens have presented difficulties of process and problems of cost. In an attempt to obtain a more rapid, sensitive, and specific test for PCM diagnosis, we subcloned the P. brasiliensis p27 gene and used the recombinant protein as the antigen in dot blot assays to evaluate its usefulness in paracoccidioidomicosis diagnosis. The development of an optimised procedure for p27 recombinant protein purification and production led to an easier and less expensive process than the one previously used in our laboratory and allowed the availability of enough purified protein for its evaluation as the antigen in the dot blot assays. In these assays, antibodies present in ten serum samples from seven patients with PCM recognised the recombinant protein showing a sensitivity of 100% with a specificity of 98%. These results confirm the value of the 27‐kDa recombinant antigen in the serodiagnosis of paracoccidioidomycosis and that the dot blot format is an alternative to the immunoenzymatic assay procedure.
Malassezia species isolated from lesional and non‐lesional skin in patients with pityriasis versicolor
Authors: Prohic Asja , Ozegovic Ladislav 
Published: December 2006

SummaryPityriasis versicolor (PV) is a superficial fungal infection where Malassezia species play a definite causative role, but the clinical significance of each of these species is not fully understood. The aim of our study was to analyse the prevalence of Malassezia species in PV lesions and to examine if the range of species varies with patient sex, age, direct microscopy findings and some clinical data. Ninety patients with PV completed the study. The samples were obtained by scraping the skin surface, both from lesional and non‐lesional skin and then incubated on Sabouraud dextrose agar and modified Dixon agar. The yeast isolated were identified according to their macroscopic and microscoipic features and physiological characteristics. In PV lesions, the most common species was M. globosa (63%), followed by M. sympodialis (14%), M. furfur (10%), M. obtusa (8%) and M. slooffiae (4%). The most frequently isolated species from clinically healthy skin were M. globosa (49%), M. sympodialis (37%) and M. furfur (5%). We found significant difference in the distribution of Malassezia species between lesional and non‐lesional skin and in the distribution of Malassezia species according to the direct microscopy findings. M. globosa in its mycelial phase is the predominant species involved in the aetiology of PV.
Anticandidal activity of Pseudomonas aeruginosa strains isolated from clinical specimens
Authors: Kaleli Ilknur , Cevahir Nural , Demir Melek , Yildirim Umut , Sahin Rasim 
Published: December 2006

SummaryPseudomonads represent the major group of non‐differentiating microorganisms that produce antibiotics. The antibiotic substances produced by this group of organisms are pyocyanin, pyrolnitrin and pseudomonic acid. This study was designed to investigate the in vivo and in vitro anticandidal activity of Pseudomonas aeruginosa strains against Candida species. Forty‐four P. aeruginosa strains isolated from various specimens of intensive care patients were included in the study. All P. aeruginosa strains have pyocyanin pigment. Candida albicans ATCC 10231, Candida parapsilosis ATCC 22019, Candida krusei ATCC 6258 and a clinical isolate of Candida tropicalis were used to measure the anticandidal activity of Pseudomonas strains by Kerr's method. The total inhibition rates obtained by using blood agar of C. albicans, C. parapsilosis, C. krusei and C. tropicalis were 41%, 34%, 34% and 25% respectively. When Sabouraud dextrose agar (SDA) was used, the rates were detected as 45%, 39%, 48% and 25% respectively. In the mouse model of concomitant subcutaneous infection with Candida species and P. aeruginosa no yeast were recovered from skin cultures despite 100% detection of P. aeruginosa. Pseudomonas aeruginosa strains isolated from intensive care patients showed anticandidal activity against the Candida species in the present study and this point may be important in the following and treatment of patients.
Mycophenolate mofetil substitution for cyclosporine‐dependent myasthenia gravis and nephrotoxicity
Authors: Lim A. K. H. , Donnan G. , Chambers B. , Ierino F. L. 
Published: December 2006

AbstractSevere autoimmune myasthenia gravis is difficult to manage and may require immunosuppression with cyclosporine. However, cyclosporine dependency is associated with the risk of nephrotoxicity. Mycophenolate mofetil is a non‐nephrotoxic alternative which should be considered to rescue cyclosporine‐dependent, severe myasthenia gravis sufferers with renal impairment from progression to end‐stage renal failure. However, the evidence is limited and studies have not assessed the outcome of a direct substitution in these cyclosporine‐dependent patients. We study three such patients who successfully converted to mycophenolate mofetil, and briefly examine the evidence behind this option. We believe that total cyclosporine withdrawal is feasible, but strongly recommend overlapping mycophenolate mofetil treatment with cyclosporine.
How does the brain mediate interpretation of incongruent auditory emotions? The neural response to prosody in the presence of conflicting lexico‐semantic cues
Authors: Mitchell Rachel L. C. 
Published: December 2006

AbstractWe frequently encounter conflicting emotion cues. This study examined how the neural response to emotional prosody differed in the presence of congruent and incongruent lexico‐semantic cues. Two hypotheses were assessed: (i) decoding emotional prosody with conflicting lexico‐semantic cues would activate brain regions associated with cognitive conflict (anterior cingulate and dorsolateral prefrontal cortex) or (ii) the increased attentional load of incongruent cues would modulate the activity of regions that decode emotional prosody (right lateral temporal cortex). While the participants indicated the emotion conveyed by prosody, functional magnetic resonance imaging data were acquired on a 3T scanner using blood oxygenation level‐dependent contrast. Using SPM5, the response to congruent cues was contrasted with that to emotional prosody alone, as was the response to incongruent lexico‐semantic cues (for the ‘cognitive conflict’ hypothesis). The right lateral temporal lobe region of interest analyses examined modulation of activity in this brain region between these two contrasts (for the ‘prosody cortex’ hypothesis). Dorsolateral prefrontal and anterior cingulate cortex activity was not observed, and neither was attentional modulation of activity in right lateral temporal cortex activity. However, decoding emotional prosody with incongruent lexico‐semantic cues was strongly associated with left inferior frontal gyrus activity. This specialist form of conflict is therefore not processed by the brain using the same neural resources as non‐affective cognitive conflict and neither can it be handled by associated sensory cortex alone. The recruitment of inferior frontal cortex may indicate increased semantic processing demands but other contributory functions of this region should be explored.
Modulation of isolated N‐methyl‐d‐aspartate receptor response under hyperbaric conditions
Authors: Mor Amir , Grossman Yoram 
Published: December 2006

AbstractIn humans, hyperbaric pressure induces the high‐pressure neurological syndrome (HPNS). HPNS is characterized by tremor, sleep disorders, electroencephalographic changes, and impairment of cognitive and motor performances. In animals, higher pressures result in convulsions and death. An increased N‐methyl‐d‐aspartate receptor (NMDAR) response has been implicated with HPNS. We studied high‐pressure effects on pharmacologically isolated NMDAR field excitatory postsynaptic potentials (fEPSPs). Hippocampal coronal brain slices from male Sprague‐Dawley rats were prepared, constantly superfused with physiological solutions, gas‐saturated at normobaric pressure and compressed up to 10.1 MPa with helium. fEPSPs were recorded from the dendritic layer of CA1 pyramidal neurones. High pressure significantly increased the single fEPSP delay, maximal initial slope, amplitude, decay time and time integral (elevated Na+ and Ca2+ influx) despite the known general decrease in glutamatergic synaptic release. The estimated negative and positive activation volumes (ΔV*) for various kinetic segments of the fEPSP suggest a complex response of the receptor to pressure. The NMDAR frequency response was tested by a train of five stimuli. At 50–100 Hz, high pressure did not increase the fEPSPs' frequency‐dependent depression and the train's time integral remained unchanged. At 25 Hz, pressure induced a larger frequency‐dependent depression and significantly increased the time integral. Our results provide, for the first time, direct information on the isolated brain NMDAR response under hyperbaric conditions. These observations may explain some increase in the excitability of single normal glutametergic fEPSPs and their frequency responses.
Analysis of synaptic ultrastructure without fixative using high‐pressure freezing and tomography
Authors: Rostaing Philippe , Real Eleonore , Siksou Léa , Lechaire Jean‐Pierre , Boudier Thomas , Boeckers Tobias M. , Gertler Frank , Gundelfinger Eckart D. , Triller Antoine , Marty Serge 
Published: December 2006

AbstractElectron microscopy allows the analysis of synaptic ultrastructure and its modifications during learning or in pathological conditions. However, conventional electron microscopy uses aldehyde fixatives that alter the morphology of the synapse by changing osmolarity and collapsing its molecular components. We have used high‐pressure freezing (HPF) to capture within a few milliseconds structural features without aldehyde fixative, and thus to provide a snapshot of living synapses.CA1 hippocampal area slices from P21 rats were frozen at −173 °C under high pressure to reduce crystal formation, and synapses on dendritic spines were analysed after cryosubstitution and embedding. Synaptic terminals were larger than after aldehyde fixation, and synaptic vesicles in these terminals were less densely packed. Small filaments linked the vesicles in subgroups. The postsynaptic densities (PSDs) exhibited filamentous projections extending into the spine cytoplasm. Tomographic analysis showed that these projections were connected with the spine cytoskeletal meshwork. Using immunocytochemistry, we found as expected GluR1 at the synaptic cleft and CaMKII in the PSD. Actin immunoreactivity (IR) labelled the cytoskeletal meshwork beneath the filamentous projections, but was very scarce within the PSD itself. ProSAP2/Shank3, cortactin and Ena/VASP‐IRs were concentrated on the cytoplasmic face of the PSD, at the level of the PSD projections.Synaptic ultrastructure after HPF was different from that observed after aldehyde fixative. The boutons were larger, and filamentous components were preserved. Particularly, filamentous projections were observed linking the PSD to the actin cytoskeleton. Thus, synaptic ultrastructure can be analysed under more realistic conditions following HPF.
A combination of total intravenous anesthesia and thoracic epidural for thymectomy in juvenile myasthenia gravis
Authors: BAGSHAW OLIVER 
Published: December 2006

SummaryJuvenile myasthenia gravis is the acquired form of the disease in children and presents with ocular signs, fatigability, weakness and bulbar problems. The majority of patients demonstrate thymic hyperplasia and have been shown to benefit from thymectomy. The main considerations for the anesthesiologist are the degree of muscle weakness, the muscle groups involved and sensitivity to neuromuscular blocking drugs and volatile agents. Total intravenous anesthesia (TIVA) with epidural analgesia is probably the anesthetic technique of choice, although the latter is often avoided, because of the risk of a very high block. Two cases of thymectomy are presented where anesthesia was provided using a combination of TIVA and thoracic epidural analgesia. Both patients tolerated the technique well and had an uncomplicated perioperative course.