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1.
Biofizika ; 60(4): 816-22, 2015.
Artigo em Russo | MEDLINE | ID: mdl-26394483

RESUMO

In this research the changes in the supramolecular structure of distilled water during germination of the seed in this water were studied. We used three methods: gravimetry, precision thermal analysis, electron work function measurements. In the first stage of seed germination--seed swelling--the seed extracts coherent domains in the water, herewith due to the transition of coherent domains adsorbed in nanofields into a stable state the flow of electromagnetic energy appears. In the second stage of the experiment--germ growing--the flow of biophotons occurs. This is evidenced by the increased water electron work function. A hypothetical model of the process of zucchini seed germination is suggested.


Assuntos
Elétrons , Germinação/fisiologia , Fótons , Sementes/crescimento & desenvolvimento , Água/química , Cucurbita/crescimento & desenvolvimento , Hidroponia
2.
Neuroscience ; 269: 143-51, 2014 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-24680856

RESUMO

Traumatic spinal cord injury induces a long-standing inflammatory response in the spinal cord tissue, leading to a progressive apoptotic death of spinal cord neurons and glial cells. We have recently demonstrated that immediate treatment with the antioxidants N-acetyl-cysteine (NAC) and acetyl-l-carnitine (ALC) attenuates neuroinflammation, induces axonal sprouting, and reduces the death of motoneurons in the vicinity of the trauma zone 4weeks after initial trauma. The objective of the current study was to investigate the effects of long-term antioxidant treatment on the survival of descending rubrospinal neurons after spinal cord injury in rats. It also examines the short- and long-term effects of treatment on apoptosis, inflammation, and regeneration in the spinal cord trauma zone. Spinal cord hemisection performed at the level C3 induced a significant loss of rubrospinal neurons 8 weeks after injury. At 2 weeks, an increase in the expression of the apoptosis-associated markers BCL-2-associated X protein (BAX) and caspase 3, as well as the microglial cell markers OX42 and ectodermal dysplasia 1 (ED1), was seen in the trauma zone. After 8 weeks, an increase in immunostaining for OX42 and the serotonin marker 5HT was detected in the same area. Antioxidant therapy reduced the loss of rubrospinal neurons by approximately 50%. Treatment also decreased the expression of BAX, caspase 3, OX42 and ED1 after 2 weeks. After 8 weeks, treatment decreased immunoreactivity for OX42, whereas it was increased for 5HT. In conclusion, this study provides further insight in the effects of treatment with NAC and ALC on descending pathways, as well as short- and long-term effects on the spinal cord trauma zone.


Assuntos
Acetilcarnitina/farmacologia , Acetilcisteína/farmacologia , Antioxidantes/farmacologia , Fármacos Neuroprotetores/farmacologia , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/fisiopatologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Axônios/efeitos dos fármacos , Axônios/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Vértebras Cervicais , Modelos Animais de Doenças , Feminino , Microglia/efeitos dos fármacos , Microglia/fisiologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia , Regeneração Nervosa/efeitos dos fármacos , Regeneração Nervosa/fisiologia , Neuroimunomodulação/efeitos dos fármacos , Neuroimunomodulação/fisiologia , Distribuição Aleatória , Ratos Sprague-Dawley , Medula Espinal/efeitos dos fármacos , Medula Espinal/fisiopatologia
4.
J Neurosci Methods ; 112(2): 145-54, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11716949

RESUMO

The efficacy of anterograde labeling of the central projections of primary afferent fibers were compared between biotinylated dextran amine (BDA), neurobiotin (NB) and Phaseolus vulgaris-leucoagglutinin (PHA-L) after injections into the L5 or T13 dorsal root ganglia (DRGs) of adult rats. Excellent labeling was obtained with BDA, which visualized fibers with fine terminal boutons in the L5 and T13 spinal cord segments, Clarke's nucleus and the gracile nucleus. Rarely observed crossed projections to the gracile nucleus and L5 ventral horn of the contralateral side could also be distinguished. Even in the most successful experiments, however, BDA labeled only about one-third of the axons originating from the injected dorsal root ganglion. BDA was also efficient as transganglionic tracer after application to the transected sciatic nerve. NB produced no significant labeling of the L5 primary afferents, and was only moderately effective on the T13 level. PHA injections resulted in sparse terminal labeling of the T13 and L5 afferents. Thus, BDA is an effective tracer for long-range labeling of primary afferent projections in the spinal cord and brain stem. Since not all stem fibers become labeled, however, the method does not allow quantification of all axon branches and terminals arising from the injected DRGs.


Assuntos
Vias Aferentes/citologia , Biotina/análogos & derivados , Dextranos , Gânglios Espinais/citologia , Neuroanatomia/métodos , Neurônios Aferentes/citologia , Fito-Hemaglutininas , Vias Aferentes/metabolismo , Animais , Transporte Axonal/fisiologia , Comunicação Celular/fisiologia , Feminino , Gânglios Espinais/metabolismo , Vértebras Lombares , Bulbo/citologia , Bulbo/metabolismo , Neuroanatomia/instrumentação , Neurônios Aferentes/metabolismo , Terminações Pré-Sinápticas/metabolismo , Terminações Pré-Sinápticas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Medula Espinal/citologia , Medula Espinal/metabolismo
5.
Exp Brain Res ; 139(2): 216-23, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11497064

RESUMO

The existence of retrograde cell death in sensory dorsal root ganglion (DRG) cells after peripheral nerve injury is well established. However, with respect to retrograde motoneuron death after peripheral nerve injury, available data are conflicting. This may partly be due to the cell counting techniques used. In the present study, quantitative morphometric methods have been used to analyse retrograde motoneuron death induced by spinal nerve injury in adult rats. For comparison, DRG cells were also included in the study. The C7 spinal nerve was transected about 10 mm distal to the DRG and exposed to the fluorescent tracer fast blue in order to retrogradely label the spinal motoneurons and DRG cells of the C7 segment. At 1-16 weeks postoperatively, the nuclei of fast-blue-labelled C7 motoneurons and DRG cells were counted in consecutive 50-microm-thick serial sections. For comparison, the physical disector technique and measurements of neuronal density were also used to calculate motoneuron number. The counts of fast-blue-labelled motoneurons revealed a delayed motoneuron loss amounting to 21% and 31% after 8 and 16 weeks, respectively (P<0.001). The remaining motoneurons exhibited 20% (P<0.05) soma atrophy. Using the physical disector technique, the motoneuron loss was 23% (P<0.001) after 16 weeks. Calculations of neuronal density in Nissl-stained sections failed to reveal any motoneuron loss, although after correction for shrinkage of the ventral horn a 14% (P<0.001) motoneuron loss was found. The fast-blue-labelled DRG neurons displayed 51% (P<0.001) cell loss after 16 weeks, and the remaining cells showed 22% (P<0.001) soma atrophy. In summary, cervical spinal nerve injury induces retrograde degeneration of both motoneurons and DRG cells. However, to demonstrate the motoneuron loss adequate techniques for cell counts have to be employed.


Assuntos
Plexo Braquial/lesões , Gânglios Espinais/fisiopatologia , Neurônios Motores/fisiologia , Ferimentos e Lesões/patologia , Animais , Morte Celular , Denervação , Feminino , Gânglios Espinais/patologia , Neurônios Motores/patologia , Degeneração Neural/patologia , Ratos , Ratos Sprague-Dawley
6.
Scand J Plast Reconstr Surg Hand Surg ; 35(4): 355-9, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11878171

RESUMO

The possibility of using the presence of the glial-cell-derived protein S-100 in serum as a marker for neuronal damage caused by spinal cord injury and plexus avulsion injury was investigated in 144 adult rats. After a spinal cord injury had been induced at the thoracic level or a plexus avulsion injury at the lumbar level, blood samples were taken and analysed for S-100 protein by a monoclonal two-site immunoluminometric assay. The two types of neurotrauma changed the kinetics of serum S-100 in different ways. After spinal cord injury it rapidly increased and within 72 hours had reached a concentration about 5 times that of the control animals. Three peak concentrations occurred at 3, 12, and 72 hours, respectively, and differed significantly from those of the control group (p < 0.05). After six days the values had returned to normal. After lumbar plexus injury alone there was no significant increase in the concentration of S-100. These results suggest that the concentration of S-100 protein in serum may be used as an early diagnostic tool for detecting neuronal damage caused by spinal cord injury or plexus avulsion associated with damage to the root entry zone.


Assuntos
Biomarcadores/sangue , Plexo Lombossacral/lesões , Proteínas S100/sangue , Traumatismos da Medula Espinal/sangue , Animais , Feminino , Ratos , Ratos Sprague-Dawley , Nervos Espinhais/lesões , Fatores de Tempo
7.
J Comp Neurol ; 428(4): 671-80, 2000 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-11077420

RESUMO

Neurotrophin-3 (NT-3) and brain-derived neurotrophic factor (BDNF) have previously been shown to support survival and axonal regeneration in various types of neurons. Also, synergistic neuroprotective effects of these neurotrophins have been reported in descending rubrospinal neurons after cervical spinal cord injury (Novikova et al., [2000] Eur. J. Neurosci. 12:776-780). The present study investigates the effects of intrathecally delivered NT-3 and BDNF on the survival and atrophy of ascending spinocerebellar neurons of Clarke nucleus (CN) after cervical spinal cord injury in adult rats. At 8 weeks after cervical spinal cord hemisection, 40% of the axotomized CN neurons had been lost, and the remaining cells exhibited marked atrophy. Microglial activity was significantly increased in CN of the operated side. Intrathecal infusion of NT-3 for 8 weeks postoperatively resulted in 91% cell survival and a reduction in cell atrophy, but did not reduce microglial activity. In spite of the fact that the CN neurons expressed both TrkC and TrkB receptors, only NT-3 had a neuroprotective effect, whereas BDNF was ineffective. Furthermore, when a combination of BDNF and NT-3 was administered, the neuroprotective effect of NT-3 was lost. The present results indicate a therapeutic potential for NT-3 in the treatment of spinal cord injury, but also demonstrate that in certain neuronal populations the neuroprotection obtained by a combination of neurotrophic factors may be less than that of a single neurotrophin.


Assuntos
Axotomia/efeitos adversos , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Interações Medicamentosas/fisiologia , Neurotrofina 3/farmacologia , Ratos/metabolismo , Degeneração Retrógrada/tratamento farmacológico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Sobrevivência Celular/fisiologia , Cerebelo/efeitos dos fármacos , Cerebelo/patologia , Cerebelo/fisiopatologia , Feminino , Microglia/citologia , Microglia/fisiologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico Sintase/metabolismo , Ratos/anatomia & histologia , Ratos Sprague-Dawley , Degeneração Retrógrada/patologia , Degeneração Retrógrada/fisiopatologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia
8.
Neuroscience ; 100(1): 171-81, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10996467

RESUMO

Brain-derived neurotrophic factor has previously been shown to promote survival and axonal regeneration in injured spinal motoneurons and, also, to modulate synaptic transmission and regulate the density of synaptic innervation in a variety of neurons. The present light and electron microscopic study demonstrates synaptotrophic effects of exogenously applied brain-derived neurotrophic factor on the synaptic composition of both normal and axonally lesioned adult rat spinal motoneurons. After L5-L6 ventral root avulsion, a massive loss of all types of boutons occurred on the somata of the lesioned motoneurons which persisted for at least 12 weeks postoperatively. We found that (i) intrathecal infusion of brain-derived neurotrophic factor during the first postoperative week did not prevent the synaptic detachment and activation of glial cells; (ii) prolonged treatment for four weeks restored synaptic covering and significantly reduced microglial reaction; (iii) the synaptotrophic effect remained significant for at least eight weeks after cessation of the treatment; (iv) brain-derived neurotrophic factor mainly supported F-type boutons with presumably inhibitory function, while it had little effect on S-type boutons associated with excitatory action; and (v) in normal unlesioned motoneurons, four weeks of treatment with brain-derived neurotrophic factor induced sprouting of F-type boutons, a loss of S-type boutons and motoneuron atrophy. The present data show that exogenous neurotrophins not only help to restore synaptic circuitry in axonally injured motoneurons, but also strongly influence the synaptic composition in normal motoneurons.


Assuntos
Axônios/fisiologia , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia , Sinapses/efeitos dos fármacos , Sinapses/fisiologia , Animais , Axotomia , Morte Celular/fisiologia , Feminino , Imuno-Histoquímica , Microscopia Eletrônica , Neurônios Motores/ultraestrutura , Terminações Pré-Sinápticas/efeitos dos fármacos , Terminações Pré-Sinápticas/fisiologia , Terminações Pré-Sinápticas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Valores de Referência , Raízes Nervosas Espinhais/lesões , Sinapses/ultraestrutura , Fatores de Tempo , Ferimentos e Lesões/patologia , Ferimentos e Lesões/fisiopatologia
9.
Eur J Neurosci ; 12(2): 776-80, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10712659

RESUMO

This study shows that both BDNF and NT-3 can prevent cell death in axotomized adult rat rubrospinal neurons (RSNs), but that the efficacy of neuroprotection depends on the temporal pattern of treatment. At 8 weeks after cervical spinal cord injury, 51% of the RSNs had died. Subarachnoidal BDNF infusion into the cisterna magna for 4 weeks resulted in neuronal hypertrophy and 71% survival. Continuous infusion for 8 weeks into the lumbar subarachnoidal space with either BDNF or NT-3 gave similar survival rates, while a combination of BDNF and NT-3 resulted in 96% survival, although the cells were atrophic. When administration of either BDNF or NT-3 was delayed and performed during postoperative weeks 5-8, the number of surviving neurons was increased compared to early treatment. Delayed treatment with a combination of BDNF and NT-3 resulted in complete survival and a reduction in neuronal atrophy. A decreased expression of TrkB receptors and microtubule-associated protein-2 in the RSNs after axotomy was counteracted by BDNF and NT-3. Microglial activity remained increased even when complete cell survival was achieved. Thus, the combination of neurotrophins as well as the temporal pattern of treatment need to be adequately defined to optimize survival of injured spinal tract neurons.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/uso terapêutico , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Neurotrofina 3/uso terapêutico , Núcleo Rubro/efeitos dos fármacos , Degeneração Retrógrada/prevenção & controle , Traumatismos da Medula Espinal/patologia , Medula Espinal/efeitos dos fármacos , Tratos Espinocerebelares/efeitos dos fármacos , Vias Aferentes/efeitos dos fármacos , Vias Aferentes/patologia , Animais , Atrofia , Fator Neurotrófico Derivado do Encéfalo/administração & dosagem , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Vértebras Cervicais , Cisterna Magna , Esquema de Medicação , Sinergismo Farmacológico , Feminino , Hipertrofia , Bombas de Infusão Implantáveis , Infusões Parenterais , Microglia/metabolismo , Microglia/patologia , Proteínas Associadas aos Microtúbulos/biossíntese , Proteínas Associadas aos Microtúbulos/genética , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Neurotrofina 3/administração & dosagem , Neurotrofina 3/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor trkB/biossíntese , Receptor trkB/genética , Núcleo Rubro/metabolismo , Núcleo Rubro/patologia , Degeneração Retrógrada/etiologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/tratamento farmacológico , Tratos Espinocerebelares/patologia , Espaço Subaracnóideo , Fatores de Tempo
10.
Morfologiia ; 118(6): 40-4, 2000.
Artigo em Russo | MEDLINE | ID: mdl-11210459

RESUMO

Using cobalt salts axonal ionophoresis posttraumatic regeneration of TXII dorsal roots nerve fibres in the zone of hemisection in conditions of 14 wks embryo spinal cord transplantation into the zone of trauma of spinal cord. Regro Invasion of dorsal roots nerve fibres into recipients posterior cords and Lissawers tract through the transitional zone "spinal cord--dorsal roots" was observed on posttransplantation d 14-120. It was show that afferent axons predominantly spread in substantia alba and substantia grisea caudal to the level of spinal cord transection with only individual fibres invading rostrad through the neuronal plate. In the transplants neurons were encountered up to d 120 of the observation although transplant neuropil was limited from recipient tissue brain by a glial and connective tissue scar. The influence of embryonal nervous tissue transplantation on intraspinal regeneration of dorsal roots afferents was discussed.


Assuntos
Transplante de Tecido Fetal , Regeneração Nervosa , Medula Espinal/transplante , Raízes Nervosas Espinhais/fisiologia , Animais , Axônios/fisiologia , Ratos , Medula Espinal/cirurgia , Raízes Nervosas Espinhais/ultraestrutura
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