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1.
J Musculoskelet Neuronal Interact ; 15(2): 123-36, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26032204

RESUMO

Traumatic spinal cord injury (SCI) causes a loss of locomotor function with associated compromise of the musculo-skeletal system. Whole body vibration (WBV) is a potential therapy following SCI, but little is known about its effects on the musculo-skeletal system. Here, we examined locomotor recovery and the musculo-skeletal system after thoracic (T7-9) compression SCI in adult rats. Daily WBV was started at 1, 7, 14 and 28 days after injury (WBV1-WBV28 respectively) and continued over a 12-week post-injury period. Intact rats, rats with SCI but no WBV (sham-treated) and a group that received passive flexion and extension (PFE) of their hind limbs served as controls. Compared to sham-treated rats, neither WBV nor PFE improved motor function. Only WBV14 and PFE improved body support. In line with earlier studies we failed to detect signs of soleus muscle atrophy (weight, cross sectional diameter, total amount of fibers, mean fiber diameter) or bone loss in the femur (length, weight, bone mineral density). One possible explanation is that, despite of injury extent, the preservation of some axons in the white matter, in combination with quadripedal locomotion, may provide sufficient trophic and neuronal support for the musculoskeletal system.


Assuntos
Sistema Musculoesquelético/patologia , Compressão da Medula Espinal/patologia , Compressão da Medula Espinal/terapia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapia , Vibração/uso terapêutico , Animais , Atrofia , Axônios/patologia , Osso e Ossos/patologia , Feminino , Fêmur/patologia , Membro Posterior/fisiopatologia , Locomoção , Músculo Esquelético/patologia , Modalidades de Fisioterapia , Desempenho Psicomotor , Ratos , Ratos Wistar , Recuperação de Função Fisiológica , Vértebras Torácicas/lesões
2.
Physiol Res ; 64(1): 129-45, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25194132

RESUMO

To determine whether the exposure to long term enriched environment (EE) would result in a continuous improvement of neurological recovery and ameliorate the loss of brain tissue after traumatic brain injury (TBI) vs. standard housing (SH). Male Sprague-Dawley rats (300-350 g, n=28) underwent lateral fluid percussion brain injury or SHAM operation. One TBI group was held under complex EE for 90 days, the other under SH. Neuromotor and sensorimotor dysfunction and recovery were assessed after injury and at days 7, 15, and 90 via Composite Neuroscore (NS), RotaRod test, and Barnes Circular Maze (BCM). Cortical tissue loss was assessed using serial brain sections. After day 7 EE animals showed similar latencies and errors as SHAM in the BCM. SH animals performed notably worse with differences still significant on day 90 (p<0.001). RotaRod test and NS revealed superior results for EE animals after day 7. The mean cortical volume was significantly higher in EE vs. SH animals (p=0.003). In summary, EE animals after lateral fluid percussion (LFP) brain injury performed significantly better than SH animals after 90 days of recovery. The window of opportunity may be wide and also lends further credibility to the importance of long term interventions in patients suffering from TBI.


Assuntos
Comportamento Animal , Lesões Encefálicas/reabilitação , Ambiente Controlado , Regeneração Nervosa , Córtex Sensório-Motor/fisiopatologia , Animais , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Lesões Encefálicas/psicologia , Modelos Animais de Doenças , Abrigo para Animais , Masculino , Aprendizagem em Labirinto , Atividade Motora , Tamanho do Órgão , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Teste de Desempenho do Rota-Rod , Córtex Sensório-Motor/patologia , Comportamento Espacial , Fatores de Tempo
3.
Restor Neurol Neurosci ; 33(2): 233-49, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25503507

RESUMO

PURPOSE: Based on several positive effects of whole-body-vibration (WBV) therapy on recovery after SCI, we looked for correlations between functional (analysis of locomotion), electrophysiological (H-reflex) and morphological (density of functioning capillaries) measurements after SCI and WBV-treatment. METHODS: Severe compression SCI at low-thoracic level (T8) in adult female Wistar rats was followed by WBV twice a day (2 × WBV) over a 12-week post-injury period. Intact rats and rats with SCI but no WBV-therapy ("No-WBV") served as controls. Recovery of locomotion was determined by BBB-locomotor rating, foot stepping angle (FSA), rump-height index (RHI), correct ladder steps (CLS) and H-reflex at 1, 3, 6, 9, and 12 weeks after SCI. Animals were sacrificed by an overdose of Isoflurane (Abbott). One hour later their spinal cords were fixed in 4% PFA for 24 h. Samples from the thoracic cord containing the lesion site and from the lumbar intumescence were cut into 10 µm thick longitudinal frozen sections. RESULTS: All functioning capillaries were unequivocally identified because the endogenous peroxidase of the erythrocytes was clearly visualized with 0.05% diaminobenzidine (DAB). A determination of their absolute (in µm2) and proportional areas (percent of photographed tissue) revealed a significantly denser capillary network in the WBV-treated rats: 1,66 ± 0,41% in the "vibrated" rats versus 0,79 ± 0,19% in the "No-WBV" animals. The portion of the capillary network in intact rats was 1,51 ± 0,69%. Surprisingly, even though the vascularization in the treated animals was significantly increased, this had no beneficial influence on the recovery of functions after SCI. CONCLUSION: The results of this study provide for the first time evidence that intensive WBV-therapy leads to a significantly denser capillary network in the lesioned spinal cord. However, since this higher capillary density is not associated with improved functional recovery (possibly because it exceeded the balance necessary for functional improvements), optional treatments with lower intensity or less time of WBV-therapy should be tested.


Assuntos
Capilares/fisiopatologia , Recuperação de Função Fisiológica/fisiologia , Compressão da Medula Espinal/fisiopatologia , Compressão da Medula Espinal/terapia , Medula Espinal/irrigação sanguínea , Vibração/uso terapêutico , Animais , Fenômenos Biomecânicos , Capilares/patologia , Modelos Animais de Doenças , Feminino , Reflexo H/fisiologia , Atividade Motora/fisiologia , Modalidades de Fisioterapia , Distribuição Aleatória , Ratos Wistar , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Compressão da Medula Espinal/patologia , Vértebras Torácicas
4.
Neuroscience ; 248: 307-18, 2013 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-23806716

RESUMO

Crush injuries of peripheral nerves typically lead to axonotmesis, axonal damage without disruption of connective tissue sheaths. Generally, human patients and experimental animals recover well after axonotmesis and the favorable outcome has been attributed to precise axonal reinnervation of the original peripheral targets. Here we assessed functionally and morphologically the long-term consequences of facial nerve axonotmesis in rats. Expectedly, we found that 5 months after crush or cryogenic nerve lesion, the numbers of motoneurons with regenerated axons and their projection pattern into the main branches of the facial nerve were similar to those in control animals suggesting precise target reinnervation. Unexpectedly, however, we found that functional recovery, estimated by vibrissal motion analysis, was incomplete at 2 months after injury and did not improve thereafter. The maximum amplitude of whisking remained substantially, by more than 30% lower than control values even 5 months after axonotmesis. Morphological analyses showed that the facial motoneurons ipsilateral to injury were innervated by lower numbers of glutamatergic terminals (-15%) and cholinergic perisomatic boutons (-26%) compared with the contralateral non-injured motoneurons. The structural deficits were correlated with functional performance of individual animals and associated with microgliosis in the facial nucleus but not with polyinnervation of muscle fibers. These results support the idea that restricted CNS plasticity and insufficient afferent inputs to motoneurons may substantially contribute to functional deficits after facial nerve injuries, possibly including pathologic conditions in humans like axonotmesis in idiopathic facial nerve (Bell's) palsy.


Assuntos
Traumatismos do Nervo Facial/reabilitação , Nervo Facial/fisiopatologia , Núcleo do Nervo Facial/citologia , Regeneração Nervosa , Terminações Pré-Sinápticas/patologia , Recuperação de Função Fisiológica , Animais , Modelos Animais de Doenças , Traumatismos do Nervo Facial/patologia , Traumatismos do Nervo Facial/fisiopatologia , Núcleo do Nervo Facial/patologia , Núcleo do Nervo Facial/fisiopatologia , Masculino , Neurônios Motores/citologia , Neurônios Motores/patologia , Compressão Nervosa/métodos , Ratos
5.
Drug Test Anal ; 5(3): 145-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21770051

RESUMO

1-(2-Thienyl)-2-(methylamino)propane (methiopropamine, MPA), the thiophene analogue of methamphetamine, has recently appeared on a number of websites offering 'legal highs' for sale and has also been reported as a new psychoactive substance by the European Monitoring Centre for Drugs and Drugs Addiction (EMCDDA) Early Warning System. The drug is currently not controlled in the European Union (EU) but it would be expected that forensic laboratories will encounter it during routine analysis. As no reference standard was available, we have established a three-step protocol for its synthesis. We have also synthesized its 3-thienyl isomer and have established that this is separable from methiopropamine by gas chromatography using one of our routine protocols. The synthetic methodology presented here could be readily extended to the syntheses of analogous compounds.


Assuntos
Estimulantes do Sistema Nervoso Central/síntese química , Drogas Ilícitas/síntese química , Metanfetamina/análogos & derivados , Tiofenos/síntese química , Estimulantes do Sistema Nervoso Central/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Drogas Ilícitas/análise , Isomerismo , Metanfetamina/análise , Metanfetamina/síntese química , Padrões de Referência , Tiofenos/análise
6.
Mol Endocrinol ; 26(9): 1531-41, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22771493

RESUMO

We have studied the regulation of ATAD2 gene expression by androgens in prostate cells. ATAD2 is a coactivator of the androgen receptor (AR) and the MYC protein. We showed that ATAD2 expression is directly regulated by AR via an AR binding sequence (ARBS) located in the distal enhancer of its regulatory region. The gene is also regulated by the E2F1 transcription factor. Using knockdown and chromatin immunoprecipitation technique approaches, we could demonstrate that AR and E2F1 functionally collaborate and physically interact between each other. From the analysis of chromatin conformation, we conclude that this cooperation results from a chromatin looping over the ATAD2 promoter region between the ARBS and E2F1 binding site in an androgen-dependent manner. Furthermore, we could show that several genes overexpressed in prostate cancer and potentially involved in several aspects of tumor development have an ARBS and an E2F1 binding site in their regulatory regions and exhibit the same mechanism of regulation by both transcription factors as ATAD2.


Assuntos
Fator de Transcrição E2F1/metabolismo , Próstata/metabolismo , Receptores Androgênicos/metabolismo , ATPases Associadas a Diversas Atividades Celulares , Adenosina Trifosfatases/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Fator de Transcrição E2F1/genética , Ensaio de Desvio de Mobilidade Eletroforética , Humanos , Imunoprecipitação , Masculino , Regiões Promotoras Genéticas/genética , Ligação Proteica , Receptores Androgênicos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
7.
Restor Neurol Neurosci ; 30(5): 363-81, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22695706

RESUMO

UNLABELLED: Following spinal cord injury (SCI), loss of spinal and supraspinal control results in desynchronisation of detrusor vesicae (parasympathicus) and external urethral sphincter (sympathicus) activity. Despite recovery of lower urinary tract function being a high priority in patients with SCI, effective treatment options are unavailable largely because mechanisms are poorly understood. PURPOSE AND METHODS: We used a clinically relevant model of thoracic SCI compression injury in adult female Wistar rats and confirmed that lesion volumes following severe injuries were significantly greater compared to moderate injuries (p < 0.05). Between 1-9 weeks, we assessed recovery of bladder function as well as return of locomotor function using the Basso, Beattie and Bresnahan (BBB) score. Bladder morphometrics and overall intramural innervation patterns, as assessed with ß-III tubulin immunohistochemistry, were also examined. RESULTS: Despite variability, bladder function was significantly worse following severe compared to moderate compression injury (p < 0.05); furthermore, the degree of bladder and locomotor dysfunction were significantly correlated (r = 0.59; p < 0.05). In addition, at 9 weeks after SCI we saw significantly greater increases in bladder dry weight (p < 0.05) and wall thickness following severe compared to moderate injury as well as increases in intramural axon density (moderate: 3× normal values; severe 5×; both p < 0.05) that also correlated with injury severity (r = 0.89). CONCLUSION: The moderate and severe compression models show consistent and correlated deficits in bladder and locomotor function, as well as in gross anatomical and histopathological changes. Increased intramural innervation may contribute to neurogenic detrusor overactivity and suggests the use of therapeutic agents which block visceromotoric efferents.


Assuntos
Transtornos dos Movimentos/etiologia , Recuperação de Função Fisiológica/fisiologia , Compressão da Medula Espinal/complicações , Compressão da Medula Espinal/patologia , Bexiga Urinaria Neurogênica/etiologia , Animais , Modelos Animais de Doenças , Feminino , Locomoção/fisiologia , Atividade Motora/fisiologia , Fibras Nervosas Mielinizadas/patologia , Tamanho do Órgão/fisiologia , Nervos Periféricos/patologia , Ratos , Ratos Wistar , Análise de Regressão , Índice de Gravidade de Doença , Fatores de Tempo , Tubulina (Proteína)/metabolismo , Bexiga Urinária/patologia , Bexiga Urinária/fisiopatologia , Bexiga Urinaria Neurogênica/patologia
9.
Neuroscience ; 182: 241-7, 2011 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-21440044

RESUMO

Functional recovery following facial nerve injury is poor. Adjacent neuromuscular junctions (NMJs) are "bridged" by terminal Schwann cells and numerous regenerating axonal sprouts. We have recently shown that manual stimulation (MS) restores whisking function and reduces polyinnervation of NMJs. Furthermore, MS requires both insulin-like growth factor-1 (IGF-1) and brain-derived neurotrophic factor (BDNF). Here, we investigated whether fibroblast growth factor-2 (FGF-2) was also required for the beneficial effects of MS. Following transection and suture of the facial nerve (facial-facial anastomisis, FFA) in homozygous mice lacking FGF-2 (FGF-2(-/-)), vibrissal motor performance and the percentage of poly-innervated NMJ were quantified. In intact FGF-2(-/-) mice and their wildtype (WT) counterparts, there were no differences in amplitude of vibrissal whisking (about 50°) or in the percentage of polyinnervated NMJ (0%). After 2 months FFA and handling alone (i.e. no MS), the amplitude of vibrissal whisking in WT-mice decreased to 22±3°. In the FGF-2(-/-) mice, the amplitude was reduced further to 15±4°, that is, function was significantly poorer. Functional deficits were mirrored by increased polyinnervation of NMJ in WT mice (40.33±2.16%) with polyinnervation being increased further in FGF-2(-/-) mice (50.33±4.33%). However, regardless of the genotype, MS increased vibrissal whisking amplitude (WT: 33.9°±7.7; FGF-2(-/-): 33.4°±8.1) and concomitantly reduced polyinnervation (WT: 33.9%±7.7; FGF-2(-/-): 33.4%±8.1) to a similar extent. We conclude that, whereas lack of FGF-2 leads to poor functional recovery and target reinnervation, MS can nevertheless confer some functional benefit in its absence.


Assuntos
Músculos Faciais/inervação , Traumatismos do Nervo Facial/genética , Traumatismos do Nervo Facial/terapia , Fator 2 de Crescimento de Fibroblastos/deficiência , Manipulações Musculoesqueléticas/métodos , Plasticidade Neuronal/genética , Recuperação de Função Fisiológica/genética , Animais , Modelos Animais de Doenças , Músculos Faciais/fisiopatologia , Traumatismos do Nervo Facial/fisiopatologia , Fator 2 de Crescimento de Fibroblastos/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Denervação Muscular/métodos , Regeneração Nervosa/genética , Vibrissas/inervação
10.
Mol Cell Endocrinol ; 332(1-2): 149-62, 2011 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-20974212

RESUMO

In this work we have studied the mechanisms of regulation of expression of androgen receptor (AR) target genes. We have used an immortalized non-tumorigenic prostate cell line RWPE-1-AR(tag) constitutively expressing an exogenous AR as a model. We observed that all studied AR target genes exhibited a specific expression during the G1 phase of the cell cycle despite the constitutive expression of AR. Importantly, we found that the expression of NCoR, an AR co-repressor, was downregulated during the G1 phase and expressed as mRNA and protein specifically during the S phase. The role of NCoR in repressing androgen-induced expression of AR target genes in S phase was further demonstrated by altering expression of NCoR during the cell cycle through knockdown or induced overexpression. Using two alternative techniques we show that AR binds directly to target DNA in the chromatin only during the G1 phase. These data support the hypothesis that NCoR might control a cell cycle dependent regulation of expression AR target genes in prostate cells.


Assuntos
Androgênios/metabolismo , Ciclo Celular/fisiologia , Regulação da Expressão Gênica , Correpressor 1 de Receptor Nuclear/metabolismo , Próstata/citologia , Receptores Androgênicos/metabolismo , Linhagem Celular , Cromatina/metabolismo , Humanos , Masculino , Correpressor 1 de Receptor Nuclear/genética , Receptores Androgênicos/genética , Transcrição Gênica
11.
Physiol Res ; 60(2): 367-75, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21114367

RESUMO

The aim of the present study was to quantify the effect of multisensory rehabilitation on rats' cognition after an experimental brain trauma and to assess its possible clinical implications. The complex intermittent multisensory rehabilitation consisted of currently used major therapeutic procedures targeted at the improvement of cognitive functions; including multisensory and motor stimulation and enriched environment. We have confirmed this positive effect of early multisensory rehabilitation on the recovery of motor functions after traumatic brain injury. However, we have been able to prove a positive effect on the recovery of cognitive functions only with respect to the frequency of efficient search strategies in a Barnes maze test, while results for search time and travelled distance were not significantly different between study groups. We have concluded that the positive effects of an early treatment of functional deficits are comparable with the clinical results in early neurorehabilitation in human patients after brain trauma. It might therefore be reasonable to apply these experimental results to human medical neurorehabilitation care.


Assuntos
Lesões Encefálicas/reabilitação , Cognição/fisiologia , Desempenho Psicomotor/fisiologia , Animais , Modelos Animais de Doenças , Masculino , Aprendizagem em Labirinto/fisiologia , Projetos Piloto , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/fisiologia
12.
Neuroscience ; 170(1): 372-80, 2010 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-20600640

RESUMO

Functional recovery following facial nerve injury is poor. Neuromuscular junctions (NMJs) are "bridged" by terminal Schwann cells and numerous regenerating axonal sprouts. We have shown that this poly-innervation of NMJs can be reduced by manual stimulation (MS) with restoration of whisking function. In addition, we have recently reported that insulin-like growth factor-1 (IGF-1) is required to mediate the beneficial effects of MS. Here we extend our findings to brain derived neurotrophic factor (BDNF). We then examined the effect of MS after facial-facial anastomosis (FFA) in heterozygous mice deficient in BDNF (BDNF(+/-)) or in its receptor TrkB (TrkB(+/-)). We quantified vibrissal motor performance and the percentage of NMJ bridged by S100-positive terminal Schwann cells. In intact BDNF(+/-) or TrkB(+/-) mice and their wild type (WT) littermates, there were no differences in vibrissal whisking nor in the percentage of bridged NMJ (0% in each genotype). After FFA and handling alone (i.e. no MS) in WT animals, vibrissal whisking amplitude was reduced (60% lower than intact) and the percentage of bridged NMJ increased (27% more than intact). MS improved both the amplitude of vibrissal whisking (not significantly different from intact) and the percentage of bridged NMJ (11% more than intact). After FFA and handling in BDNF(+/-) or TrkB(+/-) mice, whisking amplitude was again reduced (53% and 60% lower than intact) and proportion of bridged NMJ increased (24% and 29% more than intact). However, MS failed to improve outcome in both heterozygous strains (whisking amplitude 55% and 58% lower than intact; proportion of bridged NMJ 27% and 18% more than intact). We conclude that BDNF and TRkB are required to mediate the effects of MS on target muscle reinnervation and recovery of whisking function.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Denervação Muscular , Regeneração Nervosa/fisiologia , Receptor trkB/fisiologia , Recuperação de Função Fisiológica/fisiologia , Vibrissas/inervação , Vibrissas/fisiologia , Animais , Feminino , Camundongos , Camundongos Transgênicos , Estimulação Física/métodos , Distribuição Aleatória
13.
HNO ; 58(5): 426-32, 2010 May.
Artigo em Alemão | MEDLINE | ID: mdl-20454881

RESUMO

Despite increasing knowledge of cellular and molecular mechanisms determining the success or failure of peripheral nerve regeneration, no effective treatments for peripheral nerve injury exist. Newly developed and validated approaches for precise numerical assessment of motor deficits have recently allowed testing of novel strategies in experimental animals. One of these approaches is the daily manual stimulation of the denervated musculature. This treatment is effective in cases of cranial nerve lesions with preservation of the sensory input (facial or hypoglossal nerve) and has the potential of direct translation in clinical settings. However, manual stimulation appears to be ineffective for the treatment of mixed peripheral nerve injuries. Generally, no long-term improvement of functional recovery is achieved by electrical stimulation in rodents. While short-term post-traumatic stimulation of the proximal nerve stump has no negative effects, direct electrical stimulation of the muscle during the period of de- and reinnervation appears to hinder muscle fibre reinnervation. Finally, experimental evidence suggests that application of peptides known as glycomimetics, which mimic functional properties of carbohydrate molecules, may provide significant benefits after injuries of mixed peripheral nerves.


Assuntos
Terapia por Estimulação Elétrica/métodos , Traumatismos do Nervo Facial/fisiopatologia , Traumatismos do Nervo Facial/terapia , Regeneração Nervosa , Animais , Humanos
14.
Exp Neurol ; 222(2): 226-34, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20067789

RESUMO

Recently, we showed that manual stimulation (MS) of denervated vibrissal muscles enhanced functional recovery following facial nerve cut and suture (FFA) by reducing poly-innervation at the neuro-muscular junctions (NMJ). Although the cellular correlates of poly-innervation are established, with terminal Schwann cells (TSC) processes attracting axon sprouts to "bridge" adjacent NMJ, molecular correlates are poorly understood. Since quantitative RT-PCR revealed a rapid increase of IGF-1 mRNA in denervated muscles, we examined the effect of daily MS for 2 months after FFA in IGF-1(+/-) heterozygous mice; controls were wild-type (WT) littermates including intact animals. We quantified vibrissal motor performance and the percentage of NMJ bridged by S100-positive TSC. There were no differences between intact WT and IGF-1(+/-) mice for vibrissal whisking amplitude (48 degrees and 49 degrees ) or the percentage of bridged NMJ (0%). After FFA and handling alone (i.e. no MS) in WT animals, vibrissal whisking amplitude was reduced (60% lower than intact) and the percentage of bridged NMJ increased (42% more than intact). MS improved both the amplitude of vibrissal whisking (not significantly different from intact) and the percentage of bridged NMJ (12% more than intact). After FFA and handling in IGF-1(+/-) mice, the pattern was similar (whisking amplitude 57% lower than intact; proportion of bridged NMJ 42% more than intact). However, MS did not improve outcome (whisking amplitude 47% lower than intact; proportion of bridged NMJ 40% more than intact). We conclude that IGF-I is required to mediate the effects of MS on target muscle reinnervation and recovery of whisking function.


Assuntos
Músculos Faciais/fisiologia , Traumatismos do Nervo Facial/reabilitação , Fator de Crescimento Insulin-Like I/metabolismo , Estimulação Física/métodos , Recuperação de Função Fisiológica/fisiologia , Vibrissas/fisiologia , Análise de Variância , Animais , Modelos Animais de Doenças , Traumatismos do Nervo Facial/patologia , Feminino , Lateralidade Funcional/fisiologia , Regulação da Expressão Gênica/fisiologia , Manobra Psicológica , Fator de Crescimento Insulin-Like I/deficiência , Camundongos , Camundongos Knockout , Movimento/fisiologia , Ratos , Ratos Sprague-Dawley , Receptor IGF Tipo 1/metabolismo , Receptores Nicotínicos/metabolismo , Regeneração/fisiologia , Proteínas S100/metabolismo , Vibrissas/inervação
15.
J Phys Condens Matter ; 21(3): 034103, 2009 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21817248

RESUMO

Understanding the melting of short DNA sequences probes DNA at the scale of the genetic code and raises questions which are very different from those posed by very long sequences, which have been extensively studied. We investigate this problem by combining experiments and theory. A new experimental method allows us to make a mapping of the opening of the guanines along the sequence as a function of temperature. The results indicate that non-local effects may be important in DNA because an AT-rich region is able to influence the opening of a base pair which is about 10 base pairs away. An earlier mesoscopic model of DNA is modified to correctly describe the timescales associated with the opening of individual base pairs well below melting, and to properly take into account the sequence. Using this model to analyze some characteristic sequences for which detailed experimental data on the melting is available (Montrichok et al 2003 Europhys. Lett. 62 452), we show that we have to introduce non-local effects of AT-rich regions to get acceptable results. This brings a second indication that the influence of these highly fluctuating regions of DNA on their neighborhood can extend to some distance.

16.
Exp Brain Res ; 185(3): 469-83, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17955222

RESUMO

Transection and re-anastomosis of the purely motor facial nerve leads to poor functional recovery. However, we have recently shown in rat that manual stimulation (MS) of denervated vibrissal muscles reduces the number of polyinnervated motor endplates and promotes full recovery of whisking. Here, we examined whether MS of denervated rat forearm muscles would also improve recovery following transection and suture of the mixed (sensory and motor) median nerve (median-median anastomosis, MMA). Following MMA of the right median nerve, animals received no postoperative treatment, daily MS of the forearm muscles or handling only. An almost identical level of functional recovery, measured by the force of grip in grams, was reached in all animals by the sixth postoperative week and maintained till 3 months following surgery regardless of the postoperative treatment. Also, we found no differences among the groups in the degree of axonal sprouting, the extent of motor endplate polyinnervation and in the soma size of regenerated motoneurons. Taken together, we show that while MS is beneficial following motor nerve injury, combined strategies will be required for functional recovery following mixed nerve injury.


Assuntos
Membro Anterior/fisiologia , Destreza Motora/fisiologia , Músculo Esquelético/fisiologia , Traumatismos dos Nervos Periféricos , Nervos Periféricos/fisiologia , Recuperação de Função Fisiológica/fisiologia , Animais , Feminino , Membro Anterior/inervação , Neurônios Motores/fisiologia , Músculo Esquelético/inervação , Neurônios Aferentes/fisiologia , Estimulação Física/métodos , Ratos , Ratos Endogâmicos Lew
17.
HNO ; 56(2): 122-30, 2008 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-17876563

RESUMO

Using a combination of the following, it is possible to investigate procedures to improve the morphological and functional regeneration of the facial nerve in animal models: 1) retrograde fluorescence tracing to analyse collateral axonal sprouting and the selectivity of reinnervation of the mimic musculature, 2) immunohistochemistry to analyse both the terminal axonal sprouting in the muscles and the axon reaction within the nucleus of the facial nerve, the peripheral nerve, and its environment, and 3) digital motion analysis of the muscles. To obtain good functional facial nerve regeneration, a reduction of terminal sprouting in the mimic musculature seems to be more important than a reduction of collateral sprouting at the lesion site. Promising strategies include acceleration of nerve regeneration, forced induced use of the paralysed face, mechanical stimulation of the face, and transplantation of nerve-growth-promoting olfactory epithelium at the lesion site.


Assuntos
Músculos Faciais/inervação , Nervo Facial/fisiopatologia , Regeneração Nervosa/fisiologia , Animais , Axônios/fisiologia , Nervo Facial/patologia , Traumatismos do Nervo Facial/patologia , Traumatismos do Nervo Facial/fisiopatologia , Paralisia Facial/terapia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Microscopia Confocal , Microscopia de Fluorescência , Microscopia de Vídeo , Microcirurgia/métodos , Neurônios Motores/patologia , Neurônios Motores/fisiologia , Mucosa Olfatória/transplante , Estimulação Física , Ratos , Degeneração Retrógrada/patologia , Vibrissas/inervação , Gravação em Vídeo
18.
Physiol Res ; 56(3): 359-368, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16792466

RESUMO

This study used an experimental early rehabilitation model combining an enriched environment, multisensory (visual, acoustic and olfactory) stimulation and motor training after traumatic brain injury (via fluid-percussion model) to simulate early multisensory rehabilitation. This therapy will be used by brain injured patients to improve neural plasticity and to restore brain integration functions. Motor dysfunction was evaluated using a composite neuroscore test. Direct structural effects of traumatic brain injury were examined using Fluoro-Jade staining, which allows identification of degenerating neural cell bodies and processes. Animals in the rehabilitation model group performed significantly better when tested for neuromotor function than the animals in standard housing in the 7-day and 15-day interval after injury (7d: p=0.005; 15d: p<0.05). Statistical analysis revealed significantly lower numbers of Fluoro-Jade positive cells (degenerating neurons) in the rehabilitation model group (n=5: mean 13.4) compared to the standard housing group (n=6: mean 123.8) (p<0.005). It appears that the housing of animals in the rehabilitation model led to a clear functional increase in neuromotor functions and to reduced neural loss compared with the animal group in standard housing.


Assuntos
Lesões Encefálicas/reabilitação , Degeneração Neural/prevenção & controle , Animais , Lesões Encefálicas/fisiopatologia , Modelos Animais de Doenças , Ambiente Controlado , Masculino , Atividade Motora , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica
19.
Adv Anat Embryol Cell Biol ; 180: 1-130, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16261803

RESUMO

Facial nerve surgery inevitablyleads to pareses, abnormally associated movements, and pathologically altered reflexes. The reason for this "post-paralytic syndrome" is the misdirected reinnervation of targets, which consists of two major components. First, due to malfunctioning axonal guidance, a muscle gets reinnervated by a "foreign" axon, that has been misrouted along a "wrong" fascicle. Second, the supernumerary collateral branches emerging from all transected axons simultaneously innervate antagonistic muscles and cause severe impairment of coordinated activity. Since it is hardly possible to influence the first major component and improve the guidance of several thousands of axons, we concentrated on the second major component and tried to reduce the collateral axonal branching. The efficiency of various treatments was evaluated in rats by determining: (1) the degree of post-operative axonal branching as estimated by the number of double-or triple-labeled perikarya after application of crystalline DiI, Fluoro-Gold (FG), and Fast Blue (FB) to the zygomatic, buccal, and marginal mandibular branch of the facial nerve respectively; (2) the accuracy of reinnervation as estimated by the number of double-labeled perikarya innervating the whisker pad muscles before and after surgery as shown by intramuscular injections of FG and FB respectively; (3) the recovery of vibrissal motor performance, estimated by a video based motion analysis. So far, we have tried to reduce branching by alteration of the afferent trigeminal input to the axotomized facial motoneurons and by focal application of: (1) neurite outgrowth fostering ECM proteins; (2) neutralizing antibodies to NGF, BDNF, CNTF, GDNF, IGF-I, and FGF-II; (3) suspensions of olfactory ensheathing cells, Schwann cells, and bone marrow stroma cells; and (4) pieces of autologous olfactory mucosa to the transection site. Although most of these manipulations do influence peripheral nerve regeneration to some extent, only the application of autologous olfactory mucosa yielded a major improvement, i.e., better function.


Assuntos
Axônios/fisiologia , Nervo Facial/fisiologia , Músculo Esquelético/fisiologia , Animais , Ratos
20.
Proc Natl Acad Sci U S A ; 100(8): 4790-5, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12668759

RESUMO

Therapeutic vaccination with Copaxone (glatiramer acetate, Cop-1) protects motor neurons against acute and chronic degenerative conditions. In acute degeneration after facial nerve axotomy, the number of surviving motor neurons was almost two times higher in Cop-1-vaccinated mice than in nonvaccinated mice, or in mice injected with PBS emulsified in complete Freund's adjuvant (P < 0.05). In mice that express the mutant human gene Cu/Zn superoxide dismutase G93A (SOD1), and therefore simulate the chronic human motor neuron disease amyotrophic lateral sclerosis, Cop-1 vaccination prolonged life span compared to untreated matched controls, from 211 +/- 7 days (n = 15) to 263 +/- 8 days (n = 14; P < 0.0001). Our studies show that vaccination significantly improved motor activity. In line with the experimentally based concept of protective autoimmunity, these findings suggest that Cop-1 vaccination boosts the local immune response needed to combat destructive self-compounds associated with motor neuron death. Its differential action in CNS autoimmune diseases and neurodegenerative disorders, depending on the regimen used, allows its use as a therapy for either condition. Daily administration of Cop-1 is an approved treatment for multiple sclerosis. The protocol for non-autoimmune neurodegenerative diseases such as amyotrophic lateral sclerosis, remains to be established by future studies.


Assuntos
Esclerose Lateral Amiotrófica/terapia , Doença dos Neurônios Motores/terapia , Peptídeos/imunologia , Vacinas/uso terapêutico , Doença Aguda , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/imunologia , Animais , Axotomia , Morte Celular , Doença Crônica , Modelos Animais de Doenças , Nervo Facial/imunologia , Nervo Facial/patologia , Nervo Facial/fisiopatologia , Feminino , Acetato de Glatiramer , Ácido Glutâmico/toxicidade , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Doença dos Neurônios Motores/genética , Doença dos Neurônios Motores/imunologia , Neurônios Motores/imunologia , Neurônios Motores/patologia , Neurônios Motores/fisiologia , Degeneração Neural/imunologia , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Degeneração Neural/prevenção & controle , Peptídeos/uso terapêutico , Superóxido Dismutase/genética , Superóxido Dismutase-1
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