bluuebunny/crossref_metadata_2025_split huggingface dataset:
Involvement of calpain in the process of Jurkat T cell chemotaxis
Authors: Butler Jonathan T. , Samantaray Supriti , Beeson Craig C. , Ray Swapan K. , Banik Naren L. 
Published: October 2008

AbstractMassive T cell infiltration into the central nervous system is a hallmark of multiple sclerosis (MS) and its rodent model experimental autoimmune encephalomyelitis (EAE), resulting in the induction of many of the pathophysiological events that lead to neuroinflammation and neurodegeneration. Thus, blocking T cell migration into the central nervous system may reduce disease severity in MS and EAE. One potential target for reducing T cell migration is inhibition of the Ca2+‐activated neutral protease calpain. Previous studies in other cell types have demonstrated that migration is reduced by incubation of cells with calpain inhibitors. Thus, we hypothesize that calpain inhibition will reduce migration of T cells in response to and toward the chemokine CCL2. To test this hypothesis, the intracellular free Ca2+ levels in Jurkat E6‐1 T cells was first measured by the fura‐2 assay to assess whether the intracellular ion environment would support calpain activation. The intracellular free Ca2+ levels were found to increase in response to CCL2. The cells were next treated with the calpain inhibitor calpeptin in a multiwelled Boyden chamber with CCL2 used as the chemoattractant. These studies demonstrate that inhibition of calpain with its inhibitor calpeptin produces a dose‐dependent inhibition of chemotaxis. Calpain activity, as measured by live cell imaging, was also increased in response to CCL2, providing further evidence of its involvement in the process of chemotaxis and migration. These studies provide evidence for the involvement of calpain in the mechanisms of chemotaxis and warrants further exploration in MS patient and EAE animal samples. © 2008 Wiley‐Liss, Inc.
Entrainment and coupling of the hamster suprachiasmatic clock by daily dark pulses
Authors: Mendoza Jorge , Pévet Paul , Challet Etienne 
Published: October 2008

AbstractThe circadian rhythm of locomotor activity of hamsters kept in constant light (LL) can split into two distinct components that, in steady state, lie 180° apart. The splitting phenomenon is the result of antiphase circadian oscillations between left and right sides of the suprachiasmatic nuclei (SCN), the master circadian clock in mammals. In unsplit hamsters housed in LL, a single dark pulse produces a phase‐shift of the wheel‐running activity rhythm, accompanied by a transient down‐regulation of clock gene expression in the SCN. In the present study, we evaluated the effects of daily 1‐hr dark pulses on wheel‐running activity rhythm and on the expression of clock and nonclock proteins in the SCN of Syrian hamsters exposed to LL conditions. The results show that a daily 1‐hr dark pulse entrained the rhythm of wheel‐running activity of unsplit hamsters. In addition, in split animals, unimodal coupling of the two locomotor activity components was produced by daily 1‐hr dark pulses. In the SCN, the effects of entrainment and unimodal coupling of the two separate components by dark observed in behavior were also evident in the bilateral expression of the proteins c‐FOS, p‐ERK, PERIOD 1, and calbindin. These results show that the bilaterally asymmetric SCN clock, underlying split circadian behavior, can be recoupled in phase and entrained by short daily dark exposure, indicating the synchronizing potency of darkness on the main circadian clock. © 2008 Wiley‐Liss, Inc.
Minocycline: A neuroprotective agent for hypoxic‐ischemic brain injury in the neonate?
Authors: Buller Kathryn M. , Carty Michelle L. , Reinebrant Hanna E. , Wixey Julie A. 
Published: October 2008

AbstractMinocycline is a second‐generation tetracycline and a potential neuroprotective intervention following brain injury. However, despite the recognized beneficial effects of minocycline in a multitude of adult disease states, the clinical application of minocycline in neonates is contentious. Tetracyclines, as a class, are not usually administered to neonates, but there is compelling evidence that minocycline reduces brain injury after neonatal hypoxic‐ischemic brain injury. This Review focuses on the evidence for minocycline use in neonates by considering aspects of pharmacology, drug regimens, functional outcomes, and mechanisms of action. © 2008 Wiley‐Liss, Inc.
Monoamine oxidase‐B activity is not involved in the neuroinflammatory response elicited by a focal freeze brain injury
Authors: Sanz Elisenda , Quintana Albert , Valente Tony , Manso Yasmina , Hidalgo Juan , Unzeta Mercedes 
Published: October 2008

AbstractCryolesion of the frontoparietal cortex in mice is a well‐described brain injury paradigm that results in increased astrogliosis surrounding the lesion site and is accompanied by a prominent increase in the MAO‐B levels in astrocytes. Whether these increased MAO‐B levels contribute to cellular damage or modulate reactive astrocytosis remains unclear. MAO‐B activity may contribute to cellular damage, since its metabolism products are highly toxic to the cells. Additionally, it has been suggested that MAO‐B inhibition may regulate astrocytic reaction. In this study, we have determined the relative contribution of MAO‐B activity to the outcome following freeze injury. Freeze injury induced a prominent increase of several inflammatory markers, including ICAM, Mac‐1, EB22, and GFAP. Inhibition of MAO‐B activity using the selective inhibitor PF9601N did not reduce this cryolesion‐induced inflammatory response. Additional data revealed that the expression of several cryolesion‐induced cell death genes, such as Fas, Rip, p53, and ICE, was not reduced in PF9601N‐treated mice, evidencing that MAO‐B activity did not contribute to cryolesion‐induced cell death. Definitive functional analysis of the mice using the ladder beam task revealed that MAO‐B inhibition did not improve the cryolesion‐induced motor impairment. These data strongly suggest that, although MAO‐B is highly expressed in the area surrounding the lesion site, its activity does not contribute to the cellular damage or play any role in regulating astrocytic reactivity. © 2008 Wiley‐Liss, Inc.
Controlled contusion injury alters molecular systems associated with cognitive performance
Authors: Griesbach Grace Sophia , Sutton Richard L. , Hovda David A. , Ying Zhe , Gomez‐Pinilla Fernando 
Published: October 2008

AbstractWe investigated whether a learning impairment after a controlled cortical impact (CCI) injury was associated with alterations in molecules involved in synaptic plasticity and learning and memory. Adult male rats with moderate CCI to the left parietal cortex, tested in a Morris water maze (MWM) beginning at postinjury day 10, showed impaired cognitive performance compared with sham‐treated rats. Tissue was extracted for mRNA analysis on postinjury day 21. The expression of brain‐derived neurotrophic factor (BDNF), synapsin I, cyclic‐AMP response element binding protein (CREB), and calcium‐calmodulin–dependent protein kinase II (α‐CAMKII) were all significantly decreased compared with sham injury levels within the ipsilateral hippocampus after CCI. No significant molecular level changes were found in the contralateral hippocampus. Decreased expression of BDNF and synapsin I was also found within the ipsilateral parietal cortex of CCI‐injured rats compared with shams. However, BDNF and synapsin I expressions were significantly increased in the contralateral parietal cortex of the CCI rats. CREB expression was significantly decreased within the contralateral cortex of the CCI group. These findings show enduring reductions in the expression of BDNF, synapsin I, CREB, and α‐CAMKII ipsilateral to a CCI injury, which seem associated with the spatial learning deficits observed in this injury model. In addition, the delayed increase in the expression of BDNF and synapsin I within the cortex contralateral to CCI may reflect restorative processes in areas homotypical to the injury. © 2008 Wiley‐Liss, Inc.
Deletion of the amino‐terminal domain of the prion protein does not impair prion protein–dependent neuronal differentiation and neuritogenesis
Authors: Barenco Maria Grazia , Valori Chiara F. , Roncoroni Chiara , Loewer Johannes , Montrasio Fabio , Rossi Daniela 
Published: October 2008

AbstractThe cellular prion protein (PrPC) is a highly conserved glycoprotein of unknown biological function. To gain insight into the physiological role of PrPC, we generated a novel PrP knockout cell line, named PrPo/o ML, by immortalization of neuroepithelial precursor cells derived from the cerebellum of PrP‐knockout mice using the temperature‐sensitive simian virus 40 (SV40) large T antigen. We demonstrated that the PrPo/o ML cell line is a unipotent precursor line with glutamatergic properties, which can acquire neuronal features when cultivated under specific conditions. The role of the prion protein in the process of neuronal differentiation was then analyzed in the PrPo/o ML cells reconstituted with either the full‐length or an amino‐terminally deleted form of the prion protein. We show that the expression of PrPC facilitates the processes of neuronal differentiation and neuritogenesis and that the deletion of its amino‐terminal domain reduces the efficiency, but does not suppress this activity. This cell line represents a useful tool for studying PrP‐dependent signal transduction pathways during differentiation of neuronal stem/precursor cells. © 2008 Wiley‐Liss, Inc.
Regulation of relaxin 3 gene expression via cAMP‐PKA in a neuroblastoma cell line
Authors: Tanaka Masaki , Watanabe Yoshihisa , Yoshimoto Kanji 
Published: October 2008

AbstractRelaxin 3 is expressed in neurons of the brain stem that inneravate wide areas of the forebrain. Relaxin 3 mRNA levels in these neurons are increased in response to restraint stress, and by central administration of corticotropin‐releasing factor (CRF). In the present study, we observed that relaxin 3 was expressed in a mouse neuroblastoma cell line, Neuro2a, and investigated the intracellular signaling that activated relaxin 3 gene transcription in vitro. By means of a clone stably transfected with a relaxin 3 promoter‐EGFP gene, we observed that dibutyryl cyclic AMP and forskolin increased the relaxin 3 promoter activity. These increases were inhibited by pretreatment with PKA inhibitors, H89 and KT5720. Moreover, the promoter activity was enhanced by CRF treatment after expression of CRF‐R1 receptor on the cells. Taken together, these results indicate that relaxin 3 transcription is activated via the cAMP‐PKA pathway in the downstream of CRF‐R1. © 2008 Wiley‐Liss, Inc.
Intracellular glutathione mediates the denitrosylation of protein nitrosothiols in the rat spinal cord
Authors: Romero Jorge M. , Bizzozero Oscar A. 
Published: October 2008

AbstractProtein S‐nitrosothiols (PrSNOs) have been implicated in the pathophysiology of neuroinflammatory and neurodegenerative disorders. Although the metabolically instability of PrSNOs is well known, there is little understanding of the factors involved in the cleavage of S‐NO linkage in intact cells. To address this issue, we conducted chase experiments in spinal cord slices incubated with S‐nitrosoglutathione (GSNO). The results show that removal of GSNO leads to a rapid disappearance of PrSNOs (t½ ∼ 2 hr), which is greatly accelerated when glutathione (GSH) levels are raised with the permeable analogue GSH ethyl ester. Moreover, PrSNOs are stable in the presence of the GSH depletor diethyl maleate, indicating that GSH is critical for protein denitrosylation. Inhibition of GSH‐dependent enzymes (glutathione S‐transferase, glutathione peroxidase, and glutaredoxin) and enzymes that could mediate denitrosylation (alcohol dehydrogense‐III, thioredoxin and protein disulfide isomerase) do not alter the rate of PrSNO decomposition. These findings and the lack of protein glutathionylation during the chase indicate that most proteins are denitrosylated via rapid transnitrosylation with GSH. The differences in the denitrosylation rate of individual proteins suggest the existence of additional structural factors in this process. This study is relevant to our recent discovery that PrSNOs accumulate in the central nervous system of patients with multiple sclerosis. © 2008 Wiley‐Liss, Inc.
Effect of enzymes, flavor and organic acids on nutrient digestibility, performance and carcass traits of growing–finishing pigs fed diets containing dehydrated lucerne meal
Authors: Thacker Philip A , Haq Inam 
Published: October 2008

AbstractBACKGROUND: We recently determined that 150 g kg−1 of lucerne meal can be fed during the finishing period without detrimental effects on pig performance but lucerne should be limited to less than 75 g kg−1 during the growing period. Lucerne has a high fiber content, is poorly digested and contains antinutritional factors such as saponins which reduce palatability. Therefore, pig performance could be enhanced by supplementing lucerne‐containing diets with feed additives such as flavors, enzymes or organic acids. The objective of this study was to determine the effects of these additives on nutrient digestibility, performance and carcass traits when fed to growing‐finishing swine fed diets containing lucerne.RESULTS: Flavor and enzyme had no effect on nutrient digestibility, pig performance or carcass traits. During the growing period, inclusion of propionic and acetic acids increased (P < 0.05) the digestibility of dry matter, protein and energy. Weight gain and intake also increased (P < 0.05). None of the additives had any effect on pig performance during the finishing period or on carcass traits.CONCLUSION: During the growing period, including 200 g kg−1 lucerne was detrimental to pig performance. Addition of organic acid improved pig performance and nutrient digestibility. During the finishing period, 200 g kg−1 lucerne can be successfully incorporated into pig diets without negative effects on pig performance. Copyright © 2008 Society of Chemical Industry
Rapid and simple method for screening of natural antioxidants from Chinese herb Flos Lonicerae Japonicae by DPPH‐HPLC‐DAD‐TOF/MS
Authors: Tang Dan , Li Hui‐Jun , Chen Jun , Guo Chao‐Wei , Li Ping 
Published: October 2008

AbstractA rapid and simple method has been developed for the screening and identification of natural antioxidants of Flos Lonicerae Japonicae (FLJ), derived from the flower buds of Lonicera japonica. The hypothesis is that upon reaction with 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), the peak areas (PAs) of compounds with potential antioxidant effects in the HPLC chromatograms will be significantly reduced or disappeared, and the identity confirmation could be achieved by HPLC‐DAD‐TOF/MS hyphenated technique. Using the proposed approach, about 14 compounds in the FLJ extract were found to possess a potential antioxidant activity. They were identified as chlorogenic acid (1), 1‐O‐caffeoylquinic acid (1‐O‐CQA, 2), caffeic acid (4), 4‐O‐CQA (5), rutin (7), isoquercitrin (8), luteolin‐7‐O‐glucoside (9), lonicerin (10), 4,5‐O‐dicaffeoylquinic acid (4,5‐O‐diCQA, 11), 3,5‐O‐diCQA (12), 1,3‐O‐diCQA (13), 3,4‐O‐diCQA (14), 1,4‐O‐diCQA (16), and luteolin (17). In addition, the free radical scavenging capacities of the available identified compounds were also investigated by HPLC assay. The results indicated that the compounds with PAs significantly decreasing were natural antioxidants, whereas those with PAs not changing presented no activities, which accordingly indicated that this newly proposed method could be widely applied for rapid screening and identification of natural antioxidants from complex matrices including Chinese herbal medicines.
Removal of envelope protein‐free retroviral vectors by anion‐exchange chromatography to improve product quality
Authors: Rodrigues Teresa , Alves Ana , Lopes António , Carrondo Manuel J. T. , Alves Paula M. , Cruz Pedro E. 
Published: October 2008

AbstractWe have investigated the role of the retroviral lipid bilayer and envelope proteins in the adsorption of retroviral vectors (RVs) to a FractogelTM DEAE matrix. Intact RVs and their degradation components (envelope protein‐free vectors and solubilized vector components) were adsorbed to this matrix and eluted using a linear gradient. Envelope protein‐free RVs (Env–) and soluble envelope proteins (gp70) eluted in a significantly lower range of conductivities than intact RVs (Env+) (13.7–30 mS/cm for Env– and gp70 proteins vs. 47–80 mS/cm for Env+). The zeta (ζ)‐potential of Env+ and Env– vectors was evaluated showing that envelope proteins define the pI of the viral particles (pI (Env+) < 2 versus 3 < pI (Env–) < 4) and that Env+ and Env– vectors have similar ζ‐potentials within pH 5 and 8. The results presented herein indicate that the adsorption of retroviral particles occurs through multi‐point interaction of the envelope proteins with the cationic groups on the chromatographic matrix. The strength of this adsorption is thus dependent on the amount of envelope protein present in the viral lipid bilayer. In conclusion, AEXc enables the separation of gp70 proteins as well as envelope protein‐free vectors constituting a significant improvement to the quality of retroviral preparations for gene therapy applications.
Analysis of volatiles in dehydrated carrot samples by solid‐phase microextraction followed by GC‐MS
Authors: Soria Ana Cristina , Sanz Jesús , Villamiel Mar 
Published: October 2008

AbstractA solid‐phase microextraction (SPME)‐based method for the GC‐MS analysis of volatiles in dehydrated carrot root samples has been developed and the effect of the most important factors (fibre coating, extraction temperature, equilibrium time and extraction time) on the fractionation of different volatiles has been studied. GC‐MS chromatograms showed terpenoids relevant to carrot aroma such as α‐pinene, sabinene, β‐myrcene, limonene, γ‐terpinene, terpinolene, trans‐caryophyllene and β‐bisabolene, and several furan derivatives whose origin is discussed in this paper. As an example of application, this methodology has been used for the characterization of volatile composition of industrially dehydrated carrots. SPME followed by GC‐MS is shown as an affordable, fast and solvent‐free technique which can be performed with low sample amounts and be easily implemented at an industry for quality control purposes.
Determination of ascorbic acid in human plasma with a view to stability using HPLC with UV detection
Authors: Kand'ár Roman , Žáková Pavla 
Published: October 2008

AbstractA method for the measurement of ascorbic acid using HPLC with UV detection and investigation into the protein precipitation techniques with regard to stability and recovery are described. The effectiveness of various protein precipitants was tested. Stability of ascorbic acid samples for analysis was investigated over 10 h. Ascorbic acid samples extracted with metaphosphoric acid were stable on a cooled autosampler (4°C) for at least 10 h (with a decline of 1.8% for ascorbic acid solution and 2.8% for plasma). Perchloric acid as protein precipitant for ascorbic acid was unsuitable (with a decline of 36.0% for ascorbic acid solution and 7.3% for plasma). Analytical performance of this method is satisfactory. The intra‐ and interassay coefficients of variation were 2.1% (n= 10) and 5.8% (n= 12), respectively. The calibration curve was linear with the tested range of 2.0–250.0 μmol/L. The recovery was 96.1% with CV = 4.8% (n= 6) and the LOD was 3 μmol/L. The preliminary reference ranges of ascorbic acid in a group of blood donors are 50.8 ± 22.4 μmol/L. This assay is a highly sensitive and reproducible HPLC method for the determination of ascorbic acid in human plasma.
Functionalized‐multiwalled carbon nanotubes as a preconcentrating probe for rapid monitoring of cationic dyestuffs in environmental water using AP‐MALDI/MS
Authors: Shrivas Kamlesh , Wu Hui‐Fen 
Published: October 2008

AbstractA simple and sensitive method was developed for the rapid analysis of cationic dyestuffs from river and industrial wastewater using functionalized‐multiwalled carbon nanotubes (f‐MWCNT) with atmospheric pressure‐matrix assisted laser desorption/ionization mass spectrometry (AP‐MALDI/MS). The separation and preconcentration of analytes from sample solution was based on electrostatic force of attraction between positive dyestuffs and negatively charged f‐MWCNT. The optimum enrichment of the three dyestuffs was observed at pH 5.0 for 3 min contact time and using 1 mg f‐MWCNT in 1 mL water sample. The developed method has been successfully applied for the determination of three cationic dyestuffs namely neutral red (NR), brilliant cresyl blue (BB), and methylene blue (MB) in real world samples including river and industrial wastewater. The relative recoveries of dyestuffs from water sample were in the range 88.6–98.4%, indicating that the matrix had little effect on enrichment of analytes. The LOD and LOQ for cationic dyestuffs in water were 0.5–1.9 and 1.6–6.0 μg/L, respectively. All the results indicated that the proposed method could be used for the simultaneous determination of the three cationic dyestuffs in river and industrial wastewater at trace levels without the need of any chromatographic separation techniques.
Analysis of 51 persistent organic pollutants in soil by means of ultrasonic solvent extraction and stir bar sorptive extraction GC‐MS
Authors: Martínez‐Parreño Marta , Llorca‐Pórcel Julio , Valor Ignacio 
Published: October 2008

AbstractA novel method based on ultrasonic solvent extraction and stir bar sorptive extraction (SBSE) for the analysis of 51 persistent organic pollutants including organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and polybrominated diphenylethers (PBDEs) in soil samples was developed. The different parameters that affect both the extraction of analytes from the soil samples, such as solvent selection, solvent volume, mass of soil, and extraction time, and the partitioning from the solvent/water mixture to the PDMS were studied. The final selected conditions consisted of the extraction of 1 g of soil with 15 mL methanol by sonication for 30 min. The methanol extract was mixed with 85 mL of Milli‐Q water and extracted by means of SBSE for 14 h at 900 rpm. The stir bars were analyzed by thermal desorption‐GC‐mass spectometry (TD‐GC‐MS). The effects of the matrix on the recovery of the various pollutants under the developed method were studied using two soils with very different physicochemical properties. Method sensitivity, linearity, repeatability, and reproducibility were also studied. Validation and accuracy of the method were conducted by analyzing two commercial certified reference materials (CRMs). The main advantage of this method resides in the fact that a small amount of a nontoxic solvent (methanol) is needed for the extraction of only 1 g of solid sample allowing LODs ranging from 0.01 to 2.0 μg/kg. Repeatability and reproducibility variations were lower than 20% for all investigated compounds. Results of the CRMs verify the high accuracy of this method.