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  • Spinal cord trauma  (3)
  • wheat  (3)
  • Brain edema  (2)
  • 1
    ISSN: 1438-2199
    Schlagwort(e): Heat stress ; Nitric oxide ; Cell injury ; Antioxidant ; H-290/51Blood-brain barrier ; Brain edema
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The possibility that nitric oxide (NO) is involved in the pathophysiology of brain injury caused by heat stress (HS) was examined using neuronal nitric oxide synthase (NOS) immunohistochemistry in a rat model. In addition, to find out a role of oxidative stress in NOS upregulation and cell injury, the effect of a new antioxidant compound H-290/51 (Astra Hässle, Mälndal, Sweden) was examined in this model. Subjection of conscious young rats to 4 h HS in a biological oxygen demand (BOD) incubator at 38°C resulted in a marked upregulation of NOS in many brain regions compared to control rats kept at room temperature (21 ± 1°C. This NOS immunoreactivity was found mainly in distorted neurons located in the edematous regions not normally showing NOS activity. Breakdown of the blood-brain barrier (BBB) permeability, increase in brain water content and marked neuronal, glial and myelin reaction were common findings in several brain regions exhibiting upregulation of NOS activity. Pretreatment with H-290/51 significantly attenuated the upregulation of NOS in rats subjected to HS. In these animals breakdown of the BBB permeability, edema and cell changes were considerably reduced. Our results suggest that hyperthermic brain injury is associated with a marked upregulation of NOS activity in the CNS and this upregulation of NOS and concomitant cell injury can be reduced by prior treatment with an antioxidant compound H 290/51. These observations indicate that oxidative stress seems to be an important endogenous signals for NOS upregulation and cell reaction in hyperthermic brain injury.
    Materialart: Digitale Medien
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  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Acta neuropathologica 80 (1990), S. 12-17 
    ISSN: 1432-0533
    Schlagwort(e): Serotonin (5-hydroxytryptamine, 5-HT) ; Spinal cord trauma ; Ventral horn ; p-Chlorophenyl alanine ; Immunohistochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The possibility that serotonin (5-hydroxytryptamine, 5-HT) is involved in the early tissue reactions occurring in spinal cord trauma was examined in a rat model using an immunocytochemical technique. The injury was made in the form of a 5-mm long and 2.5-mm wide lesion of the right dorsal horn at the level of T10–11. Injured rats, pretreated with the 5-HT synthesis blocking agent, p-chlorophenyl alanine (p-CPA) were compared with untreated injured controls and the animals were allowed to survive for 5 h. The distribution of 5-HT was examined in proximal and distal cross-sections of the cord, located 2 and 5 mm away from the injury. Normal rats showed immunoreactive material in nerve cell processes and in a few nerve cell bodies of the ventral horns. The trauma to the spinal cord caused a marked increase in 5-HT immunoreactivity in the segments located 2 mm proximal and distal to the injury, particularly in the ipsilateral ventral horn. The segment located 5 mm distal to the lesion showed a similar increase in immunoreactivity but it was apparently less pronounced in the corresponding proximal segment. Treatment with p-CPA markedly reduced the trauma-induced increase in 5-HT immunoreactivity in all the segments. These immunohistochemical findings were in line with the changes in the contents of 5-HT measured biochemically in corresponding spinal cord segments. At the onset of the trauma to the spinal cord 5-HT is thus present in the tissue, mainly in the form of 5-HT-containing nerve cell processes. Biochemical determinations also revealed that there is an increased amount of 5-HT in the traumatized spinal cord. The present study indicates that this is at least partly due to an increased amount of 5-HT in neurons and nerve cell processes of the perifocal region. The pathophysiollogical significance of the observed 5-HT-reaction in spinal cord injury is not known in all its details. However, 5-HT might be implicated in such tissue reaction, such as increased microvascular permea bility and edema formation occurring in the early period after trauma.
    Materialart: Digitale Medien
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  • 3
    ISSN: 1432-0533
    Schlagwort(e): Spinal cord trauma ; Glial fibrillary acidic protein ; Serotonin ; p-Chlorophenylalanine ; Immunohistochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The possibility that serotonin may influence the early response of astrocytes around a spinal cord trauma was investigated in a rat model by making a unilateral incision into the right dorsal horn of the T10-11 segments. One group of rats received a serotonin synthesis inhibitor, p-chlorophenylalanine (p-CPA) before injury in doses which cause a depletion of serotonin in the cord. Another group of traumatised rats did not receive p-CPA. All animals were allowed to survive for 5 h. Samples for immunohistochemistry were taken from the T9, T10-11 and T12 segments of the cord. Paraffin sections were immunostained for glial fibrillary acidic protein (GFAP) using monoclonal antibodies and avidin-biotin complex technique. Trauma to the cord resulted in a marked increase of GFAP immunoreactivity in all the investigated segments, particularly in the ipsilateral side. Pretreatment with p-CPA markedly reduced the GFAP response. This drug did not by itself influence the GFAP immunoreactivity of the cord of untraumatised rats. Our results show that trauma to the spinal cord induces a rapid enhancement of GFAP immunoreactivity in the cord which is present even far away from the primary lesion. This response can be prevented by pretreatment with the serotonin synthesis inhibitor, p-CPA. The results indicate that serotonin influences the increase of GFAP immunoreactivity following spinal cord injury either directly or indirectly, for instance by its microvascular reactions.
    Materialart: Digitale Medien
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  • 4
    ISSN: 1432-0533
    Schlagwort(e): Spinal cord trauma ; Edema ; Myelin basic protein ; Indomethacin ; Prostaglandins
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary The possibility that prostaglandins participate in the formation of perifocal edema and cell changes following a localized trauma to the spinal cord was investigated in a rat model. A laminectomy was performed in urethane-anesthetized animals at the thoracic T10–11 segment. Using a scalpel blade a unilateral lesion, about 2 mm deep and 5 mm long was made 1 mm to the right of the midline. The deepest part of the injury occupied Rexed's lamina VII of the dorsal horn. Animals were pretreated with the prostaglandin synthesis inhibitor, indomethacin (10 mg/kg, i.p. 30 min prior to trauma). Five hours after the injury the water content was determined and cell changes in and around the primary lesion were examined by light and electron microscopy. Normal and injured rats without indomethacin pretreatment served as controls. Untreated injured rats showed a profound increase of water content in the traumatized T10–11, the rostral (T9) and caudal (T12) segments compared with normal rats. These segments also exhibited marked cell changes in ipsilateral and contralateral dorsal and ventral horns. The gray matter had a spongy appearance and some nerve cells were condensed and distorted. The white matter contained many distorted fibers. Immunostaining for myelin basic protein showed a marked reduction of reaction product in the injured animals compared with normal rats. Ultrastructurally widened extracellular spaces, cytoplasmic vacuolation, swollen and condensed neurons, swollen astrocytes and vesiculation of myelin were frequent findings. Pretreatment of rats with indomethacin significantly reduced the accumulation of water in the traumatized and in the rostral and caudal segments. The structural changes were less pronounced particularly in the cranial and caudal segments. The results indicate that prostaglandins somehow are involved in the pathophysiology of perifocal spinal cord injury and influence both the fluid microenvironment and the early cell changes.
    Materialart: Digitale Medien
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  • 5
    ISSN: 1438-2199
    Schlagwort(e): Keywords: Amino acids ; Hyperthermia ; Heat stress ; Brain edema ; Nitric oxide synthase ; Heme oxygenase ; Oxidative stress ; H-290/51 ; Cell injury
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary. Influence of a new anti-oxidant compound H-290/51 on expression of nitric oxide synthase (NOS) and heme oxygenase (HO) enzymes responsible for nitric oxide (NO) and carbon monoxide (CO) production, respectively was examined in the CNS following heat stress in relation to cell injury. Exposure of rats to 4 h heat stress at 38°C in a biological oxygen demand (BOD) incubator (relative humidity 50–55%, wind velocity 20–25 cm/sec) resulted in profound edema and cell injury in many parts of the cerebral cortex, hippocampus, cerebellum, thalamus, hypothalamus and brain stem. Immunostaining of constitutive isoforms of neuronal NOS (nNOS) and HO-2 revealed marked upregulation in damaged and distorted neurons located within the edematous brain regions. Pretreatment with H-290/51 (50 mg/kg, p.o., 30 min before heat stress) significantly reduced the edematous swelling and cell injury and resulted in a marked attenuation of nNOS and HO-2 expression. These observations suggest that upregulation of NOS and HO is associated with cell injury, and the antioxidant compound H-290/51 is neuroprotective in heat stress.
    Materialart: Digitale Medien
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  • 6
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 82 (1995), S. 43-64 
    ISSN: 1573-5060
    Schlagwort(e): wide cross ; wide hybridization ; interspecific cross ; Triticeae ; Agropyron complex ; wheatgrasses ; Triticum ; wheat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Wide crosses in wheat are reviewed in relation to various factors that facilitate wide crossing to show that wide crosses can be as wide as one can make them. Included in this review is a particular reference to wheat-wheatgrass (Agropyron complex) crosses and an update on wide crosses of wheat with various genera of Agropyron complex. Hybrid seed set is too variable to predict whether a wide hybrid, where no seed was obtained in one attempt, will not be possible. High crossability genes seem to facilitate not only fertilization but also seed development, enabling embryo rescue. Variability for crossability occurs not only in wheat but also in alien species. Contrary to conventional thinking, several wide hybrids with wheat can be produced when species with lower chromosome numbers are used as female parents. Pre-and post-fertilization barriers to wide crosses do not appear to be equally strong, and can be overcome by the development and application of various technologies. Considering these aspects of wide hybridization, and based on recent successes in producing previously unsuccessful and very wide hybrids, it is concluded that how wide cross between plant species can be made is an open question and that many new and wider hybrids can be produced in future.
    Materialart: Digitale Medien
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  • 7
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 49 (1990), S. 209-214 
    ISSN: 1573-5060
    Schlagwort(e): Triticum aestivum ; wheat ; Agropyron spp. ; embryo rescue ; wide crosses ; crossability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary Soft winter wheat lines were crossed with Agropyron intermedium, A. elongatum and A. trichophorum using pollen from single plants of Agropyron spp. to pollinate wheat spikes. Not only species but also individual plants within varieties of Agropyron species differed in percent seed set with a wheat genotype. In two arrays of crosses between two phenotypically different plants of A. elongatum and nine wheat lines, one Agropyron plant gave higher seed set (overall=27.1%) than the other (overall=3.7%). The differences were significant in seven of the nine cross combinations. Results are consistent with the hypothesis that these two plants differ in their crossability as pollen parents with wheat, and suggest the possibility of occurrence of crossability genes in wheatgrasses. The success rate of hybrid embryo rescue was higher (87.5%) with cold treatment (4°C) than without cold treatment (75.0%) of excised embryos on culture media. Results underscore the significance of genotype of the alien species for crossing with low crossable wheats, and of the physical factors for improving embryo rescue in wide crosses.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Plant cell, tissue and organ culture 24 (1991), S. 233-236 
    ISSN: 1573-5044
    Schlagwort(e): anther culture ; cultivars ; Triticum aestivum ; wheat
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Twenty-two cultivars and lines of winter and spring wheat (Triticum aestivum L.) were studied, most for the first time, for their anther culture response. The response was genotype dependent. Plants grown in the field gave higher callus induction frequency than those grown in the greenhouse and the controlled environment chamber. Donor plants grown in a season of low drought stress as compared to a season of severe drought stress resulted in a higher frequency of callus induction. Spherical microcalli were observed in two wheat genotypes in some of only those anthers that were placed with only one loculus in contact with the medium. Wheat lines that were more responsive to anther culture were identified.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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