bluuebunny/crossref_metadata_2025_split huggingface dataset:
A study of juvenile rat spinal cord injury
Authors: Wingrave J. M. , Matzelle D. D. , Wilford G. G. , Hogan E. L. , Banik N. L. 
Published: July 2010

Greater than 5% of all spinal cord injuries (SCI) in the US occur in people younger than 16, although a minority, children will require extended attention during their lifetime. While facing increased mortality in the initial 24 h after trauma, children with incomplete injuries seem to have a greater capacity for recovery of function compared to adults suggesting that there is a difference in injury tolerance in the young over the adult. Knowledge of the factors involved in this difference would not only increase understanding of SCI, but also potentiate new avenues for SCI treatment. Yet there has not been a model for the study of youth SCI. For these reasons, we developed a model of SCI in juvenile rats equivalent to an adult injury of 25 g cm force (GCF). To do so, we recorded spinal cord masses of Sprague–Dawley rats at 21, 30, 45, and 60 days of age, compared them to adult cord masses, and assembled a conversion factor that provides youth injuries comparable to adult. To investigate the pathophysiology in juvenile SCI, two cord segments, 1 cm long, were removed from animals 24 h following injury. One segment was centered at the impact site, the other immediately caudal. After homogenization, the samples were assayed by Western blot analysis for calpain content and degradation of 68K Neuro‐Filament Protein (68K NFP), a neuronal structural protein. mCalpain expression, a neutral protease previously implicated in secondary SCI, was reduced in juvenile animals relative to adult cohorts. The degradation of 68K NFP was also found to be reduced in juvenile animals. From these analyses, it seems plausible that calpain expression and pathogenic activity is abated in the setting of young rat SCI.Acknowledgements:  Supported by grants from NIH‐NINDS.
Interleukin 1 dependent cell loss after spinal cord injury (SCI)
Authors: Nesic O. , Svrakic N. M. , Xu G.‐Y. , McAdoo D. , Westlund K. N. , Hulsebosch C. E. , Perez‐Polo R. J. 
Published: July 2010

We hypothesized that blocking receptors for pro‐inflammatory cytokine, interleukin‐1 (IL‐1) would ameliorate SCI‐dependent cell loss and resulting motor dysfunction. We found that chronic administration of recombinant IL‐1 receptor antagonist (rIL‐1ra) reduced SCI‐induced increases in cell death markers and caspase‐3 activity, suggesting that IL‐1ra prevents apoptosis in injured spinal cords. We also found that IL‐1ra significantly improved locomotor recovery. To answer the question how is the inhibition of IL‐1 receptors preventing cell death in injured spinal cord and improving motor recovery, we analyzed transcriptional changes in injured vs. injured spinal cord treated with IL‐1ra, via DNA microarrays. We found a large number of mRNAs whose expression levels were significantly changed after SCI and reversed in the presence of IL‐1ra. For example, we found that iNOS and COX‐2 mRNA are significantly up‐regulated after injury and down‐regulated in IL‐1ra‐treated spinal cords. If iNOS and COX‐2 proteins are synthesized, it is very likely that their activity will produce reactive oxygen species (ROS), which will cause cell death via different converging apoptotic pathways. We also found that SCI induces IL‐1 dependent up‐regulation of pro‐apoptotic cathepsins and cell cycle regulators, a novel finding. Therefore, we hypothesize that the anti‐inflammatory IL‐1ra could be therapeutic and alleviate secondary damage after SCI.Acknowledgements:  Supported in part by grant NS39161 from NINDS and Mission Connect Foundation.
Inhibition of peroxisomal functions and production of excessive oxidative stress by psychosine in rat C6 glial cells
Authors: Khan M. , Giri S. , Singh I. , Singh A. K. 
Published: July 2010

The primary defect of abnormality in the metabolism of psychosine in Krabbe disease results in the loss of oligodendrocytes, increased oxidative stress, inflammatory reactions and profound demyelination. To understand the basis of toxicity of psychosine in the CNS of Krabbe disease, we examined the effects of psychosine on the peroxisomal β‐oxidation of very long chain fatty acids (VLCFA), plasmalogen biosynthesis and on the production of reactive oxygen/nitrogen species. Rat C6 glial cells were treated with psychosine (2–10 mm) in absence and presence of cytokines (LPS + IFN‐γ, or TNF‐α + IL‐1β) for 24 and 72 h. Psychosine inhibited peroxisomal b‐oxidation of VLCFA (30–40% decrease compared to control) and induced the accumulation of VLCFA measured as levels of 26 : 0 (100% increase compared to control). Furthermore, psychosine treatment decreased the levels of plasmalogens (35–50% decrease compared to control). Plasmalogens levels were also drastically low in Krabbe brain than normal control brain. Psychosine also potentiated the known cytokine‐induced inhibition of peroxisomal β‐oxidation, accumulation of VLCFA and NO production. We also measured overall oxidative stress using dichlorofluorescin diacetate in psychosine‐treated cells and found 1–2 fold increase in oxidative stress production. Both psychosine‐mediated loss of peroxisomal functions as well as ROS production could be inhibited by antioxidant, N‐acetylcysteine. Our results suggest that inhibition of peroxisomal functions and increased free radical production by psychosine may be responsible, at least in part, for the loss of oligodendrocytes and break down of myelin in Krabbe brain.Acknowledgements:  Supported by NIH grants NS‐40144, NS‐40810, NS‐22576, NS‐34741 and NS‐37766.
Nitric oxide – mediated activation of ERK and JNK during hypoxia in neuronal nuclei of newborn pigs
Authors: Miahra O. P. , Ashraf Q. M. 
Published: July 2010

The extracellular signal‐regulated kinase (ERK) and c‐Jun N‐Terminal kinase (JNK) phosphorylate antiapoptotic proteins thereby may regulate hypoxia‐induced programmed cell death. The present study tests the hypotheses that hypoxia activates ERK and JNK in neuronal nuclei of newborn pigs and the hypoxa‐induced activation of ERK and JNK is mediated by nitric oxide (NO). Activated ERK and JNK were assessed by determining phosphorylated ERK and JNK by immunoblotting in 6 normoxic (Nx), 10 hypoxic (Hx) and 5 N‐nitro‐l‐arginine (a NOS inhibitor)‐treated (40 mg/kg) hypoxic (NNLA‐HX) 3–5‐day‐old‐piglets. Animals were exposed to an FiO2 of 0.05–0.07 for 60 min Neuronal nuclei were isolated and nuclear proteins were immunoblotted with antiphosphorylated ERK and JNK. Protein bands were detected, analyzed and expressed as (OD × mm2). Tissue hypoxia was documented by ATP levels. ATP levels were 4.45 ± 0.57, 1.16 ± 0.33 and 1.10 ± 0.25 µm/g br in Nx, Hx (p < 0.001 vs. Nx) and NNLA‐Hx (p < 0.001 vs. Nx) groups, respectively. Phosphorylated ERK density was 170.5 ± 53.7 in Nx vs. 419.6 ± 63.9 in the Hx group (p < 0.001) and 270.0 ± 28.7 in the NNLA‐Hx group (p < 0.002 vs. Hx). Density of phosphorylated JNK was 172.8 ± 42.8 in the Nx vs. 364.6 ± 60.1 in the Hx (p < 0.002 vs. Nx) and 254.8 ± 24.8 in the NNLA‐Hx group (p < 0.002 vs. Hx). We data demonstrate increased activation of ERK and JNK following hypoxia. NNLA,a NOS inhibitor, decreased the hypoxia‐induced activation of ERK and JNK. We conclude that the hypoxia‐induced activation of ERK and JNK is NO‐mediated.Acknowledgements:  Supported by NIH‐HD‐38079.
Novel mediators of ischemic preconditioning induced neuroprotection
Authors: Dhodda V. K. , Sailor K. , Dempsey R. J. , Vemuganti R. L. R. 
Published: July 2010

A brief ischemic episode induces protection against a subsequent severe ischemic insult. This phenomenon, known as ischemic preconditioning (PC) might be mediated by the activation of several genes of the second messenger signalling pathways. A 60‐min transient middle cerebral artery occlusion (MCAO) in adult, SHR rats results in an infarct encompassing cerebral cortex and striatum by 24 h reperfusion. Present study observed that a 10‐min PC, 3 days before the 60 min transient MCAO, results in a 30% reduction in the infarct volume. To understand the molecular mechanisms of the PC induced neuroprotection, we analyzed the mRNA expression profiles of rat cerebral cortex at 6, 24 and 72 h after a 10‐min transient MCAO by using Affymetrix GeneChip and real‐time PCR. Expression of the members of TGF‐β signalling (TGF‐β1, p 38 MAP kinase, Smad 1 and Smad 7) is observed to be up‐regulated after PC. This pathway plays an essential role in tissue repair and immune homeostasis, but not hitherto implicated in PC induced neuroprotection. TGF‐β1 enhances Smad transcriptional activity through activation of P38 gene expression to induce neuroprotection. Consistent with previous studies, expression of several neuroprotective genes including HSP70, HSP27, HO‐1, MT‐1/MT‐2 and IL‐6, were also observed to be up‐regulated after PC. These studies shows that TGF‐β1/p38 MAP‐kinase signalling pathway is a promising target for developing drugs to limit ischemic neuronal damage.Acknowledgements:  Funded by AHA.
Apoptosis of neurons in rats with experimental allergic encephalomyelitis
Authors: Guyton K. , Wingrave M. , Rocchini A. , Scheacher K. , Ray S. , Banik N. 
Published: July 2010

Experimental allergic encephalomyelitis (EAE) is a rat model of multiple sclerosis (MS). In MS and EAE, calpain expression is increased in cells of the central nervous system including astrocytes, oligodendrocytes and microglia; as well as infiltrating macrophages and T cells. However, calpain expression in neurons has not previously been reported in the EAE model. Since degeneration of neurons has been demonstrated in progressive cases of MS, and calpain has been implicated in cell death in EAE, it is hypothesized that neurons expressing increased levels of calpain may undergo apoptosis. To test the hypothesis, spinal cords were collected from control and EAE rats from 4 to 12 days after challenge with guinea‐pig myelin and complete Freund's adjuvant. Apoptosis in neurons was determined by combined TUNEL and immunoflourescent staining using a neuron‐specific marker (NeuN). Calpain expression in neurons was determined using double‐immunoflourescent staining with antibodies specific for calpain and NeuN. At 8 and 9 days postchallenge, neither apoptosis nor increased calpain expression were detected in neurons in control or 9 day EAE spinal cord sections. In contrast, at 11 days postinduction neurons in acute EAE were TUNEL‐positive, indicating that cells underwent apoptosis. Further studies are in progress to determine if and when oligodendrocytes in EAE rats are apoptotic. By correlating cell‐specific increases in calpain expression with apoptosis in EAE, a better understanding of the role of calpain in EAE and MS might be achieved. This increased knowledge could suggest a potential benefit of calpain inhibitors in the treatment of EAE and MS.Acknowledgements:  Supported in part by grants from NIH‐NINDS.
Role of bone morphogenetic protein signalling in noradrenergic neuron development
Authors: Rohrer H. , Stanke M. , Schneider C. , Muller F. , Howard M. , Vogel‐Hopker A. 
Published: July 2010

The autonomic nervous system serves as an excellent model system in which one can study the emergence of distict neuronal subtypes, noradrenergic and cholinergic neurons, from the pool of pluripotent neural crest stem cells.We have shown that signalling molecules of the family of bone morphogenetic proteins (BMPs) are essential for sympathetic neuron development. BMPs are expressed in the vicinity of developing sympathetic ganglia and control the expression of a group of transcription factors that are involved in the further specification and differentiation of sympathetic neurons. This group of transcription factors includes the bHLH proteins Mash1 and dHand and the paired homeodomain transcription factors Phox2a and Phox2b. Each of these factors is sufficient to elicit the generation of sympathetic neurons, expressing subtype‐specific and pan‐neuronal genes, to elicit the early development of sympathetic neurons. In the the central nervous system, the development of noradrenergic neurons of the locus coeruleus (LC) depends on Mash1, Phox2a and Phox2b and our recent results reveal that LC neurons are generated in response to the graded action of BMPs in the dorsal hindbrain.Supported by grants from the Deutsche Forschungsgemeinschaft, Fonds der chemischen Industrie and the EU.
CNS glial progenitors and schwann cells in neurofibromatosis Type 1
Authors: Ratner N. , Miller S. J. , Ling B. , Huang Y. N. , Bennett M. R. , Mckinnon R. , Rizvi T. A. 
Published: July 2010

Neurofibromatosis type 1 (NF1) one of the most common of all autosomal dominant disorders, affecting about 1 in 3500 individuals. NF1 is considered to be a tumor suppressor disease, in which lack of the NF1 gene product causes disease. NF1 predisposes patients to central nervous system dysfunction including learning disabilities and brain tumors, to bright spots on MRI scans, postulated to be nests of dysmyelination, and to peripheral nerve tumors, both benign and malignant. Glial abnormalities might account for some or all of these defects. To test this, we prepared cultures from spinal cords of embryonic day 12.5 mouse embryos with NF1 mutations. The data show that glial progenitors, both O2A cells and glial restricted progenitors (GRPs) are dramatically amplified in cultures from mutant mice spinal cords, as compared to cultures from wild type littermates. Cells with a single mutant allele show an intermediate phenotype; signalling pathway defects including elevated Ras‐GTP appear to cause the increased cell number. Schwann cells cultured from NF1 mutant E12.5 dorsal root ganglia are also highly abnormal. Mutant Schwann cells differentially express the epidermal growth factor receptor protein (EGFR). EGFR was tested for ability to drive tumor formation in transgenic mice‐ CNPase‐EGFR mice show nerve thickening, consistent with early tumor formation. The data are consistent with a key role for glial cells in brain and peripheral nerve dysfunction in NF1.Acknowledgements:  Supported by NIH‐NS28840, the DOD Program on Neurofibromatosis, and the NMSS.
Symposium 10: Differentiation Plasticity of Stem Cells. Direct differentiation of radial glial cells from embryonic stem cells
Authors: Liour S. S. , Yu R. K. 
Published: July 2010

The major role of radial glial cells in neuronal development is to provide support and guidance for neuronal migration. In vitro, neurons, astrocytes and oligodendrocytes have also been generated from neural stem cells and embryonic stem cells, but the generation of radial glial cells in vitro has not yet been reported. Since radial glial cells can lead to neurons and astrocytes during brain development, neurogenesis and gliogenesis of stem cells in vitro may at least in part also utilize the same mechanisms. To test this hypothesis, we utilized five different clones of embryonic (ES) and embryonal carcinoma (EC) stem cell lines to investigate the differentiation of radial glial cells during in vitro neural differentiation. Here, we demonstrate that radial glial cells can be generated from ES/EC cell lines. These ES/EC cell‐derived radial glial cells are similar in morphology to radial glial cells in vivo. They also express several cytoskeletal markers that are characteristics of radial glial cells in vivo. The processes of these in vitro‐generated radial glial cells are organized into scaffolds that appear to support the migration of newly generated neurons in culture. Like radial glial cells in vivo, they appear to differentiate subsequently into astrocytes. Differentiation of radial glial cells may be a common pathway during in vitro neural differentiation of ES cells. This novel in vitro model system may facilitate the investigation of regulation of radial glial cell differentiation and its biological function.Acknowledgements:  Supported by USPHS Grant NS11853 and a grant from the Children's Medical Research Foundation.
Potential of umbilical cord blood cells for brain repair
Authors: Sanberg P. R. , Chopp M. , Willing A. E. , Zigova T. , Saporta S. , Song S. , Bickford P. , Garbuzova‐Davis S. , Newman M. , Cameron D. F. , Sanchez‐Ramos J. 
Published: July 2010

Our laboratory is characterizing the mononuclear cells from human umbilical cord blood (HUCB) for possible therapeutic value. Studies on HUCB cells demonstrated their ability to respond to growth factors by increased expression of neural markers and down regulation of several genes associated with development of blood lines. HUCB cells were also transplanted into the subventricular zone of the developing rat brain. It was found that some of the HUCB cells responded to external factors and were able to adopt neural fates similar to endogenous stem cells. We also tested whether intravenously infused HUCB cells enter brain, survive, differentiate and improve neurological functional recovery after stroke or traumatic brain injury (TBI) in rats. HUCB cells were injected into the tail vein at least 24 h after stroke or TBI. Behavioral impairments were significantly improved as early as 14 days in both TBI and stroke animals, compared to controls. Injected cells entered brain and migrated into the parenchyma of the injured brain. Some of these expressed neuronal, astrocytic, or endothelial markers. Our data suggest that intravenous administration of HUCB cells can provide neural stem cells, and may be a useful treatment for brain repair.Acknowledgements:  Supported by Saneron CCEL Therapeutics, Inc. and a FL Hi‐Tech Corridor Grant.
P2 Receptors of microglia: sensors for danger signals in the CNS
Authors: Di Virgilio F. 
Published: July 2010

Following tissue damage or invasion by pathogens a number of soluble signals are generated to alert the immune system of the impending danger and initiate inflammation. Some danger signals are released from injured or dying cells. Once released, danger signals activate a autocrine/paracrine network that recruits inflammatory cells, stimulates cytokine production, promotes dendritic cell maturations and increases the antigen (Ag) presenting efficiency. These events also occurs in the central nervous system (CNS) where cytokines and cytokine‐releasing cells have a central role in spreading inflammation. P2 receptors of microglia are the focus of increasing interest, especially after they were shown to mediate chemotaxis, cytokine release and cell death in microglia. We propose that P2 receptors may function in microglia as sensors of the ATP/UTP concentration in the pericellular space, and therefore as sensors of danger signals in the CNS. Furthermore, microglia itself can release ATP when stimulated by inflammatory stimuli. Thus extracellular nucleotides may be included in the family of the early inflammatory mediators acting via P2 receptors to spread inflammation in the CNS.References  1. Ferrari D., Villalba M., Chiozzi P., Falzoni S., Ricciardi‐Castagnoli P. and Di Virgilio F. (1996) Mouse microglia cells express a plasma membrane pore gated by extracellular ATP. J. Immunol.156, 1531–1539.2. Ferrari D., Chiozzi P., Falzoni S., Hanau S. and Di Virgilio F. (1997) Purinergic modulation of interleukin‐1B release from microglia cells stimulated with bacterial endotoxin. J. Exp. Med.185, 579–582.
The unfolded protein response is activated in Pelizaeus–Merzbacher disease
Authors: Gow A. , Southwood C. M. , Garbern J. , Jiang W. 
Published: July 2010

Of the myriad physiological processes ongoing in all living organisms, few are more important to survival at the levels of the cell and the organism than adaptations to stress. Even primordial life forms contended with ever changing environmental conditions by rapid changes at the transcriptional and post‐transcriptional levels and since that time virtually all species have retained, and expanded, rudimentary signalling pathways that preserve life under adverse conditions. In eukaryotes, one of these pathways is known as the unfolded protein response (UPR), which connects events in the endoplasmic reticulum with transcription through a receptor kinase cascade.Herein, we demonstrate activation of the UPR in patients with the leukodystrophy, Pelizaeus‐Merzbacher disease (PMD), and show that this pathway is activated by coding region mutations in, but not duplication of, the PLP1 gene. Moreover, we demonstrate that the CHOP gene product, currently the most reliable indicator of an activated UPR, plays a pivotal role in the pathogenesis of PMD. These data indicate that the UPR may potentially modulate the severity of disease in any cell type expressing mutant secretory pathway proteins. Thus, PMD is the first member of a novel class of disparate degenerative diseases linked by a common molecular mechanism.
Alterations in the Host Defense Properties of Human Milk Following Prolonged Storage or Pasteurization
Authors: Akinbi Henry , Meinzen‐Derr Jareen , Auer Christine , Ma Yan , Pullum Derek , Kusano Ryosuke , Reszka Krzysztof J , Zimmerly Kira 
Published: July 2010

ABSTRACTObjectives:Preterm infants are often fed pasteurized donor milk or mother's milk that has been stored frozen for up to 4 weeks. Our objectives were to assess the impact of pasteurization or prolonged storage at −20°C on the immunologic components of human milk and the capability of the different forms of human milk to support bacterial proliferation.Materials and Methods:The concentrations and activities of major host defense proteins in the whey fractions of mother's milk stored for 4 weeks at −20°C or pasteurized human donor milk were compared with freshly expressed human milk. Proliferation of bacteria incubated in the 3 forms of human milk was assessed.Results:Relative to freshly expressed human milk, the concentrations of lysozyme, lactoferrin, lactoperoxidase, and secretory immunoglobulin A were reduced 50% to 82% in pasteurized donor milk and the activities of lysozyme and lactoperoxidase were 74% to 88% lower (P < 0.01). Proliferation of bacterial pathogens in pasteurized donor milk was enhanced 1.8‐ to 4.6‐fold compared with fresh or frozen human milk (P < 0.01).Conclusions:The immunomodulatory proteins in human milk are reduced by pasteurization and, to a lesser extent, by frozen storage, resulting in decreased antibacterial capability. Stringent procedure to minimize bacterial contamination is essential during handling of pasteurized milk.
A recombinant trispecific single‐chain Fv derivative directed against CD123 and CD33 mediates effective elimination of acute myeloid leukaemia cells by dual targeting
Authors: Kügler Markus , Stein Christoph , Kellner Christian , Mentz Kristin , Saul Domenica , Schwenkert Michael , Schubert Ingo , Singer Heiko , Oduncu Fuat , Stockmeyer Bernhard , Mackensen Andreas , Fey Georg H. 
Published: July 2010

SummaryTwo trivalent constructs consisting of single‐chain Fv antibody fragments (scFvs) specific for the interleukin‐3 receptor α chain (CD123), CD33 and the Fcγ‐receptor III (CD16) were designed and characterized for the elimination of acute myeloid leukaemia (AML) cells. The dual targeting single‐chain Fv triplebody (sctb) [123 × ds16 × 33] and the mono targeting sctb [123 × ds16 × 123] both specifically bound their respective target antigens and were stable in human serum at 37°C for at least 5 d. Both constructs induced potent antibody‐dependent cellular cytotoxicity (ADCC) of two different AML‐derived CD33‐ and CD123 double‐positive cell lines in the low picomolar range using isolated mononuclear cells (MNCs) as effector cells. In these experiments the dual targeting molecule produced significantly stronger lysis than the mono targeting agent. In addition, the sctbs showed a high potency in mediating ADCC of primary leukaemia cells isolated from peripheral blood or bone marrow of seven AML patients. Hence, these novel molecules displayed potent anti‐leukaemic effects against AML cells in vitro and represent attractive candidates for further preclinical development.