bluuebunny/crossref_metadata_2025_split huggingface dataset:
Induction of bone marrow stromal cells to neurons: Differentiation, transdifferentiation, or artifact?
Authors: Lu Paul , Blesch Armin , Tuszynski Mark H. 
Published: May 2004

AbstractDifferentiation of stem cells toward a neuronal lineage normally involves a gradually progressive restriction in developmental potential and is regulated by a diverse set of specific and temporally precise genetic events. However, recent studies have indicated that both rodent and human bone marrow stromal cells (MSCs) can be rapidly (within minutes to hours) induced to differentiate into neurons in vitro by relatively simple chemical means (using β‐mercaptoethanol [BME] or dimethylsulfoxide [DMSO] and butylated hydroxyanisol [BHA]; Woodbury et al. [ 2000] J. Neurosci. Res. 61:364–370). The ability to transdifferentiate an easily accessible cell source into neurons could have substantial potential for promoting neural repair. We therefore explored the potential of simple chemical methods to transdifferentiate other cell types, including primary rat fibroblasts, primary human keratinocytes, HEK293 cells, rat PC‐12 cells, and as positive control rat bone marrow stromal (BMS) cells. Surprisingly, all cells except for keratinocytes adopted at least partial “neuron‐like” pyramidal cell morphology with fine‐cellular extensions resembling neurites upon stimulation with BME or DMSO/BHA. However, time‐lapse microscopy indicated that the chemical exposure of MSCs did not result in new neurite growth but rather cellular shrinkage, with retraction of the majority of existing cell extensions, leaving only few, fine neurite‐like processes. To determine whether the chemically induced transdifferentiation resulted from simple cellular toxicity, MSCs were exposed to various stressors, including detergents, high‐molarity sodium chloride, and extremes of pH. In all cases, cellular shrinkage and adoption of pseudoneuronal morphology were observed. Concomitantly with cellular shrinkage, apparent increases in immunolabeling for the neuronal markers NSE and NeuN were detected in the cell soma that could not be confirmed by RT‐PCR. Furthermore, blockade of protein synthesis with cycloheximide did not prevent cells from adopting “neuron‐like” morphology after chemical induction. Thus, morphological changes and increases in immunolabeling for certain cellular markers upon “chemical induction” of MSCs are likely the result of cellular toxicity, cell shrinkage, and changes in the cytoskeleton and do not represent regulated steps in a complicated cellular differentiation process. © 2004 Wiley‐Liss, Inc.
Effects of NF‐κB oligonucleotide “Decoys” on gene expression in P7 rat hippocampus after hypoxia/ischemia
Authors: Qiu Jingxin , Hu Xiaoming , Nesic Olivera , Grafe Marjorie R. , Rassin David K. , Wood Thomas G. , Perez‐Polo J. Regino 
Published: May 2004

Abstract“Decoy” oligonucleotides can be used as gene‐specific nuclear factor (NF‐κB) inhibitors to regulate gene expression. We applied two different decoy oligonucleotides that contained the NF‐κB binding consensus sequences present in the immunoglobulin G (IgG)‐κB and Bcl‐x promoter into 7‐day‐old (P7) rat lateral ventricles before hypoxia/ischemia (HI) and compared their effects on gene expression in hippocampi to saline‐treated, scrambled decoy‐treated, or untreated hippocampi exposed to HI. Left hippocampi were collected at 12 hr after HI. Electrophoretic mobility shift assays (EMSAs) showed that the two decoy treatments had different effects on NF‐κB binding to the IgG‐κB and Bcl‐x promoter‐specific consensus sequences, respectively. We assessed the decoys' effects on gene expression 12 hr after HI using ribonuclease protection assays (RPAs) and Affymetrix DNA microarrays. RPAs showed that both decoys significantly decreased interleukin (IL)‐1α mRNA levels but had no impact on IL‐1β, IL‐6, and IL‐10 mRNA levels. IgG‐κB decoys significantly decreased tumor necrosis factor (TNF)‐α and TNF‐β mRNA levels compared to minimal changes after treatment with Bcl‐x decoys. DNA microarray analyses showed that Bcl‐x decoy treatment significantly decreased Bcl‐xL mRNA levels. The decreased Bcl‐xL mRNA levels after Bcl‐x decoy treatment was confirmed by RPA analysis. DNA microarray data also indicated that several other genes were affected by both decoys. Our results suggest that different NF‐κB decoy treatments could differentially regulate transcriptional responses to central nervous system trauma. Careful design of decoy sequences, however, is essential to acquire selective effects on cell death outcome. © 2004 Wiley‐Liss, Inc.
Matrix metalloproteinase‐9 promotes nerve growth factor‐induced neurite elongation but not new sprout formation in vitro
Authors: Shubayev Veronica I. , Myers Robert R. 
Published: May 2004

AbstractMatrix metalloproteinase‐9 (MMP‐9) is a basal‐lamina‐degrading protease that we have recently shown to be localized in regenerating sciatic nerve. We now demonstrate that MMP‐9 colocalizes with growth‐associated protein GAP‐43 in regenerating nerves in vivo and is involved in vitro in axonal sprouting. By using a PC12 cell model for neuronal sprouting, we analyzed the effects of recombinant MMP‐9, MMP‐9‐neutralizing antibody, and a broad‐spectrum MMP inhibitor (Ro 31‐9790) on sprout formation, elongation, and branching. Quantitative phase‐contrast microscopy showed that MMP‐9 elongated neuronal sprouts by 67% and increased their branching by 14% but did not change the number of sprouts relative to nerve growth factor (NGF) treatment. Double immunofluorescence for GAP‐43, a marker for growth cones, and α‐tubulin, a marker for axonal microtubules, showed that MMP‐9‐treated cells had increased distribution of α‐tubulin but no effect on GAP‐43. Western blot analyses of cell lysates demonstrated that the NGF‐induced increase in GAP‐43 was unchanged with MMP‐9 treatment or inhibition, confirming that MMP‐9 had no effect on new sprout formation. However, Ro 31‐9790 reduced GAP‐43 levels to those seen in untreated cells, suggesting that an MMP other than MMP‐9 is important for sprout formation. Finally, phosphorylated neurofilament M (NFM‐p), a marker for regenerative elongation, was induced with MMP‐9 treatment and was inhibited by the anti‐MMP‐9 antibody treatment, confirming the role of MMP‐9 in axonal elongation. NFM‐p colocalized with MMP‐9 in regenerating sciatic nerve fibers. These findings suggest that MMP‐9 regulates neurite extension in regenerating peripheral nerve fibers and, therefore, might be of therapeutic value in promoting regeneration in vivo. © 2004 Wiley‐Liss, Inc.
Exercise‐induced behavioral recovery and neuroplasticity in the 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine‐lesioned mouse basal ganglia
Authors: Fisher Beth E. , Petzinger Giselle M. , Nixon Kerry , Hogg Elizabeth , Bremmer Samuel , Meshul Charles K. , Jakowec Michael W. 
Published: May 2004

AbstractPhysical activity has been shown to be neuroprotective in lesions affecting the basal ganglia. Using a treadmill exercise paradigm, we investigated the effect of exercise on neurorestoration. The 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐lesioned mouse model provides a means to investigate the effect of exercise on neurorestoration because 30–40% of nigrostriatal dopaminergic neurons survive MPTP lesioning and may provide a template for neurorestoration to occur. MPTP‐lesioned C57 BL/6J mice were administered MPTP (four injections of 20 mg/kg free‐base, 2 hr apart) or saline and divided into the following groups: (1) saline; (2) saline + exercise; (3) MPTP; and (4) MPTP + exercise. Mice in exercise groups were run on a motorized treadmill for 30 days starting 4 days after MPTP lesioning (a period after which MPTP‐induced cell death is complete). Initially, MPTP‐lesioned + exercise mice ran at slower speeds for a shorter amount of time compared to saline + exercise mice. Both velocity and endurance improved in the MPTP + exercise group to near normal levels over the 30‐day exercise period. The expression of proteins and genes involved in basal ganglia function including the dopamine transporter (DAT), tyrosine hydroxylase (TH), and the dopamine D1 and D2 receptors, as well as alterations on glutamate immunolabeling were determined. Exercise resulted in a significant downregulation of striatal DAT in the MPTP + exercise compared to MPTP nonexercised mice and to a lesser extent in the saline + exercised mice compared to their no‐exercise counterparts. There was no significant difference in TH protein levels between MPTP and MPTP + exercise groups at the end of the study. The expression of striatal dopamine D1 and D2 receptor mRNA transcript was suppressed in the saline + exercise group; however, dopamine D2 transcript expression was increased in the MPTP + exercise mice. Immunoelectron microscopy indicated that treadmill exercise reversed the lesioned‐induced increase in nerve terminal glutamate immunolabeling seen after MPTP administration. Our data demonstrates that exercise promotes behavioral recovery in the injured brain by modulating genes and proteins important to basal ganglia function. © 2004 Wiley‐Liss, Inc.
Cytotoxic mechanisms by M239V presenilin 2, a little‐analyzed Alzheimer's disease‐causative mutant
Authors: Abe Yoichiro , Hashimoto Yuichi , Tomita Yusuke , Terashita Kenzo , Aiso Sadakazu , Tajima Hirohisa , Niikura Takako , Matsuoka Masaaki , Nishimoto Ikuo 
Published: May 2004

AbstractAlthough neurotoxic functions are well characterized in familial Alzheimer's disease (FAD)‐linked N141I mutant of presenilin (PS)2, little has been known about M239V‐PS2, another established FAD‐causative mutant. We found that expression of M239V‐PS2 caused neuronal cytotoxicity. M239V‐PS2 exerted three forms of cytotoxicity: one was sensitive to both an antioxidant glutathione‐ethyl‐ester (GEE) and a caspase inhibitor Ac‐DEVD‐CHO (DEVD); the second was sensitive to GEE but resistant to DEVD; and the third was resistant to both. The GEE/DEVD‐sensitive cytotoxicity by M239V‐PS2 was likely through NADPH oxidase and the GEE‐sensitive/DEVD‐resistant cytotoxicity through xanthine oxidase (XO). Both mechanisms by M239V‐PS2 were suppressed by pertussis toxin (PTX) and were mediated by Gαo, but not by Gαi. Although Aβ1–43 itself induced no cytotoxicity, Aβ1–43 potentiated all three components of M239V‐PS2 cytotoxicity. As these cytotoxic mechanisms by M239V‐PS2 are fully shared with N141I‐PS2, they are most likely implicated in the pathomechanism of FAD by PS2 mutations. Notably, cytotoxicity by M239V‐PS2 could be inhibited by the combination of two clinically usable inhibitors of superoxide‐generating enzymes, apocynin and oxypurinol. © 2004 Wiley‐Liss, Inc.
Comparative study of cell culture and purification methods to obtain highly enriched cultures of proliferating adult rat Schwann cells
Authors: Mauritz Christina , Grothe Claudia , Haastert Kirsten 
Published: May 2004

AbstractWe present here a fast protocol that could be used to obtain highly purified cultures of maximal proliferating adult rat Schwann cells. These adult rat Schwann cells can be transfected in a nonbiological way using the physical transfection method of electroporation. Schwann cells are decisive in recovery of peripheral nerves after injury. In a clinical context, the use of enriched adult Schwann cells is necessary for autologous cell transplantation within nerve transplants for peripheral nerve repair. Different parameters such as tissue preparation, culture conditions, and protocols for enrichment, elevation of proliferation rates, and transfection were evaluated in cell cultures harvested from adult rat peripheral nerves. Cell preparation from in vivo predegenerated adult rat sciatic nerves combined with the use of melanocyte growth medium supplemented with forskolin, fibroblast growth factor (FGF)‐2, and pituitary extract as a selective, serum‐free culture medium, with a secondary cell‐enrichment step using specific detachment, resulted in highly enriched cultures of adult rat Schwann cells (>90%) with enhanced proliferation rates (≥40%). About 20% of these adult Schwann cells could be modified genetically using an optimized electroporation protocol. © 2004 Wiley‐Liss, Inc.
Optimising the determination of maize endosperm vitreousness by a rapid non‐destructive image analysis technique
Authors: Erasmus Corinda , Taylor John RN 
Published: May 2004

AbstractA rapid non‐destructive image analysis technique was developed and optimised for the determination of maize endosperm vitreousness without the need for sample preparation. Maize kernel translucency measurements were optimised for a light system consisting of positioning whole kernels on top of round illuminated areas smaller than the projected areas of the kernels, allowing light to shine through the kernels. A correction factor to allow for constant illumination of kernels was developed to adjust for kernel size variation in relation to constant light area. The intensity of translucency in maize is linearly correlated to the percentage of kernel illumination (r = 0.99, p < 0.001). Significant correlations were found between corrected translucency values and endosperm yields determined by hand dissection. These were: translucency as a percentage of the whole kernel and vitreous endosperm (mass%), r = 0.77; translucency as a percentage of the whole kernel and opaque endosperm (mass%), (r = −0.72); translucency as a percentage of endosperm and vitreous endosperm (mass%), r = 0.81; and translucency as a percentage of endosperm and opaque endosperm (mass%), r = −0.77; with n = 245 in all instances. Translucency varied by 29.5% between the lowest and highest values, and vitreous endosperm (mass%) varied by 16.8% between the lowest and highest values. Correlations increased significantly after corrections for kernel thickness. A thickness increase of 1 mm in the maize will cause a decrease of 21.86% in translucency and vice versa. The method allows for large samples (at least 49 kernels min−1) to be analysed for individual vitreous and opaque endosperm contents with no interferences with kernel structure. With further development of suitable automated sampling techniques, it could become a suitable potential method for in‐line quantification of maize endosperm contents. Copyright © 2004 Society of Chemical Industry
Physicochemical, cooking and textural characteristics of some Indian black gram (Phaseolus mungo L) varieties
Authors: Singh Narpinder , Kaur Maninder , Sandhu Kawaljit Singh , Sodhi Navdeep Singh 
Published: May 2004

AbstractPhysicochemical, cooking and textural properties of black gram varieties were studied and related to each other using Pearson correlation. Different varieties showed significant variation in their physicochemical, cooking and textural properties. Varieties having higher seed weight and seed volume had higher values of cooking time, swelling capacity, hydration capacity and hardness. The relationships between textural parameters of cooked grains from different black gram varieties showed a significant positive correlation of hardness with cohesiveness (r = 0.472), gumminess (r = 0.938) and chewiness (r = 0.859). Swelling index, cohesiveness and gumminess of black gram varieties were observed to be related to their fibre content. Swelling capacity and swelling index correlated well with cooking time, hardness and gumminess. Cooking time had a positive correlation with hardness (p < 0.05) and gumminess (p < 0.05) and a negative correlation with springiness. Copyright © 2004 Society of Chemical Industry
Effectiveness of antioxidant‐impregnated film in retarding lipid oxidation
Authors: Lee Youn Suk , Shin Han‐Seung , Han Jong‐Koo , Lee Myunghoon , Giacin Jack R 
Published: May 2004

AbstractThe effectiveness of an antioxidant‐impregnated film to retard autoxidation of a packaged model product containing linoleic acid, via an evaporation/sorption mechanism, was evaluated as a function of storage time and temperature. The rate of loss of antioxidant from the package film structure was described by a first‐order expression. The first‐order rate constants were dependent on the initial concentration of antioxidant in the film. The rate of loss of 3,5‐di‐tert‐butyl‐4‐hydroxytoluene (BHT) from the package film structure was found to be much higher than the rate of loss of α‐tocopherol at both storage conditions (23 and 45 °C, 50% relative humidity) studied. A freeze‐dried model food product system was developed as the source for the autoxidation of linoleic acid in storage stability studies. The storage stability of this model food system packaged with antioxidant‐impregnated film pouches was evaluated. Hexanal as an index of oxidation from the model product system was collected by a dynamic purge and trap system and quantified by a gas chromatography/mass spectrometry procedure. The BHT‐impregnated laminate pouch showed a notable effectiveness in retarding lipid oxidation of the model product at 45 °C as a function of storage time. The control (non‐antioxidant) and α‐tocopherol‐impregnated laminate pouch structures showed no effect on retarding lipid oxidation of the model product during storage at 45 °C. Copyright © 2004 Society of Chemical Industry
The foaming of mixtures of albumin and hordein protein hydrolysates in model systems
Authors: Bamforth CW , Milani C 
Published: May 2004

AbstractAlthough hydrolysed albumin and hydrolysed hordein derived from barley are independently capable of stabilising foams in model beer solutions, when both are present together, the net foam stability is less than anticipated. In particular, it seems that hordein, even in an unhydrolysed state, interferes with the ability of albumin‐derived polypeptides to stabilise foam. It appears, therefore, that the observed foam stability of a product such as beer is not only dependent on the absolute level of individual foam‐stabilising polypeptides but also on the relative proportions of polypeptides derived from the albumin and hordein protein subsets. Copyright © 2004 Society of Chemical Industry
Storage affects the phenolic profiles and antioxidant activities of cherries (Prunus avium L) on human low‐density lipoproteins
Authors: Gonçalves Berta , Landbo Anne‐Katrine , Let Mette , Silva Ana Paula , Rosa Eduardo , Meyer Anne S 
Published: May 2004

AbstractFour sweet cherry cultivars (cvs), Burlat, Saco, Summit and Van, were analysed at harvest and after storage at 2 and 15 °C for 30 and 6 days respectively. Phenolic profiles in methanolic extracts of freeze‐dried samples of the fresh and differently stored cherries were quantified by high‐performance liquid chromatography. Hydroxycinnamates dominated in all samples and represented 60–74% by weight of the phenols in the fresh and stored samples of the cvs Saco, Summit and Van, and 45% by weight of the phenols in the cv Burlat samples, which were richer in anthocyanins. The relative and total levels of hydroxycinnamates, anthocyanins, flavonols and flavan‐3‐ols varied among cultivars and during storage. Storage at 15 °C increased the phenol levels, particularly the cyanidin‐3‐rutinoside concentration. Cold storage induced decreased total phenol levels in the cvs Summit and Van but increased total phenol levels in the cvs Burlat and Saco. Phenolic cherry extracts inhibited low‐density lipoprotein oxidation in vitro in a dose‐dependent manner. Extracts of freshly harvested cherries exhibited significantly higher antioxidant activities than extracts of stored samples. The cv Summit samples had the highest antioxidant activity. Differences in the antioxidant effects of the cherry samples were positively correlated with their levels of p‐coumaroylquinic acid (p < 0.1) but negatively correlated with their cyanidin‐3‐rutinoside levels (p < 0.05). Copyright © 2004 Society of Chemical Industry
Laminarin in the dietary fibre concept
Authors: Devillé Christelle , Damas Jacques , Forget Philippe , Dandrifosse Guy , Peulen Olivier 
Published: May 2004

AbstractDietary fibres consist of edible plant polysaccharides that are resistant to digestion and absorption in the human small intestine but undergo complete or partial fermentation in the colon. Seaweeds, notably Laminaria spp, are particularly rich in polysaccharides resistant to hydrolysis in the upper gastrointestinal tract and are, in consequence, considered as dietary fibres. Most of the carbohydrates from Laminaria spp are thought to be indigestible by humans. The main storage polysaccharide of these algae is laminarin, a β‐polymer of glucose. The aims of this work were, on the one hand, to compare various methods of extraction of laminarin by partial characterisation of the product obtained and, on the other hand, to study the fate of this polysaccharide and its effects in the gastrointestinal tract in order to determine its potential as a dietary fibre in human nutrition. Among four methods tested to extract laminarin, the best appeared to be a hot HCl‐based method. Human digestive enzymes did not hydrolyse laminarin, so this polysaccharide can be considered as a dietary fibre. After ingestion by rats, this polysaccharide was not found in faeces of these animals. It did not increase the intestinal transit and stool output in vivo, but it increased the contractile response of the stomach to acetylcholine in vitro. Copyright © 2004 Society of Chemical Industry
Changes in chemical composition of coconut (Cocos nucifera) water during maturation of the fruit
Authors: Jackson José C , Gordon André , Wizzard Gavin , McCook Kayanne , Rolle Rosa 
Published: May 2004

AbstractChanges in chemical composition of coconut (Cocos nucifera) water, including total and soluble solids, titratable acidity (as citric acid), turbidity, ash, lipids and sugars, were investigated in four varieties of coconuts at four stages of maturity of the fruit. The most significant change was observed in the volume of nut water, which increased during development from 233 to 504 ml, with the greatest quantity found at 9 months. Fat, protein, soluble solids, acidity and turbidity also increased steadily with maturity, while pH and ash showed variation throughout maturation. The interaction of variety and stage of maturity of the fruit appeared to have a significant effect on the chemical composition of the coconut water. Copyright © 2004 Society of Chemical Industry
The effects of natural antioxidants and lighting conditions on the quality characteristics of gilt‐head sea bream fillets (Sparus aurata) packaged in a modified atmosphere
Authors: Giménez Begoña , Roncalés Pedro , Beltrán José A 
Published: May 2004

AbstractThe effects of lighting conditions and the application of natural antioxidants (rosemary extract and ascorbic acid) on the shelf‐life of gilt‐head sea bream fillets (Sparus aurata) packaged in a modified atmosphere (MAP) and stored at 1 ± 1 °C were studied. Lighting with low‐UV colour‐balanced lamps led to an extension of shelf‐life compared with that under supermarket fluorescent tubes, as assessed by lipid oxidation (TBARS value) and sensory evaluation. The application of antioxidants to the surface of MAP fillets delayed lipid oxidation besides improving the sensory quality. Rosemary extract was more effective than ascorbic acid in delaying lipid oxidation under both kinds of lighting. The effect of ascorbic acid was greater in the samples illuminated by low‐UV tubes than in those stored under conventional lighting. However, the effectiveness of rosemary extract was similar in both kinds of lighting conditions. Copyright © 2004 Society of Chemical Industry