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1.
BJPsych Open ; 9(3): e94, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37231817

RESUMO

BACKGROUND: Early-life adverse experiences can elevate the magnitude of the risk of developmental psychopathology, but the potential synergistic effects of multiple factors have not been well studied. AIMS: To determine whether prenatal exposures to maternal stress (Superstorm Sandy) and maternal cannabis use synergistically alter the risk of developmental psychopathology. METHOD: The study included 163 children (53.4% girls), longitudinally tracked (ages 2-5 years) in relation to the effects of two early-life adverse exposures (Superstorm Sandy and maternal cannabis use). Offspring were grouped by exposure status (neither, only maternal cannabis use, only Superstorm Sandy or both). DSM-IV disorders for offspring were derived from structured clinical interviews; caregiver-reported ratings of family stress and social support were also assessed. RESULTS: A total of 40.5% had been exposed to Superstorm Sandy and 24.5% to maternal cannabis use. Offspring exposed to both (n = 13, 8.0%), relative to those exposed to neither, had a 31-fold increased risk of disruptive behavioural disorders (DBDs) and a seven-fold increased risk of anxiety disorders. The synergy index demonstrated that offspring with two exposures had synergistic elevation in risk of DBDs (synergy index, 2.06, P = 0.03) and anxiety disorders (synergy index, 2.60, P = 0.004), compared with the sum of single risks. Offspring with two exposures had the highest parenting stress and lowest social support. CONCLUSIONS: Our findings are consistent with the double-hit model suggesting that offspring with multiple early-life adverse exposures (Superstorm Sandy and maternal cannabis use) have synergistically increased risks of mental health problems. Given the increasing frequency of major natural disasters and cannabis use, especially among women under stress, these findings have significant public health implications.

2.
Eur Arch Psychiatry Clin Neurosci ; 271(8): 1445-1453, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32940786

RESUMO

Movement slowness, linked to dysfunctional basal ganglia and cerebellum, is prevalent but lacks effective therapy in patients with schizophrenia spectrum disorders. This study was to examine immediate effects of rhythmic auditory stimulation (RAS) on upper-limb movement speed in patients. Thirty patients and 30 psychiatrically healthy people executed the right-hand task and the both-hand task of the Purdue Pegboard Test when listening to RAS with two tempi: normal (equal to the fastest movement tempo for each participant without RAS) and fast (120% of the normal tempo). The testing order of the RAS tempi for each participant was randomized. Patients had lower scores of right-hand and both-hand tasks than did psychiatrically healthy people. Scores of right-hand and both-hand tasks were higher in the fast-RAS condition than the normal-RAS condition in participants. This is the first study to explore the possibility of applying RAS to movement therapy for patients with schizophrenia spectrum disorders. The results demonstrated that faster RAS was effective in inducing faster upper-limb movements in patients and psychiatrically healthy people, suggesting that manipulating RAS may be a feasible therapeutic strategy utilized to regulate movement speed. The RAS may involve alternative neural pathways to modulate movement speed and thus to compensate for impaired function of basal ganglia and cerebellum in patients.


Assuntos
Estimulação Acústica , Movimento , Esquizofrenia , Extremidade Superior , Humanos , Movimento/fisiologia , Esquizofrenia/fisiopatologia , Esquizofrenia/terapia , Resultado do Tratamento , Extremidade Superior/fisiologia
3.
J Neuropathol Exp Neurol ; 77(4): 325-343, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29420729

RESUMO

When spinal roots are torn off from the spinal cord, both the peripheral and central nervous system get damaged. As the motoneurons lose their axons, they start to die rapidly, whereas target muscles atrophy due to the denervation. In this kind of complicated injury, different processes need to be targeted in the search for the best treatment strategy. In this study, we tested glial cell-derived neurotrophic factor (GDNF) treatment and fetal lumbar cell transplantation for their effectiveness to prevent motoneuron death and muscle atrophy after the spinal root avulsion and delayed reimplantation. Application of exogenous GDNF to injured spinal cord greatly prevented the motoneuron death and enhanced the regeneration and axonal sprouting, whereas no effect was seen on the functional recovery. In contrast, cell transplantation into the distal nerve did not affect the host motoneurons but instead mitigated the muscle atrophy. The combination of GDNF and cell graft reunited the positive effects resulting in better functional recovery and could therefore be considered as a promising strategy for nerve and spinal cord injuries that involve the avulsion of spinal roots.


Assuntos
Células-Tronco Fetais/transplante , Fator Neurotrófico Derivado de Linhagem de Célula Glial/uso terapêutico , Neurônios Motores/fisiologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/cirurgia , Animais , Sobrevivência Celular , Colina O-Acetiltransferase/metabolismo , Embrião de Mamíferos , Feminino , Células-Tronco Fetais/fisiologia , Asseio Animal/fisiologia , Proteínas de Homeodomínio/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Bainha de Mielina/metabolismo , Regeneração Nervosa , Proteínas de Neurofilamentos/metabolismo , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/fisiologia , Reimplante , Medula Espinal/citologia , Tubulina (Proteína)/metabolismo
4.
Int J Mol Sci ; 18(3)2017 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-28264437

RESUMO

Injuries to peripheral nerves are frequent in serious traumas and spinal cord injuries. In addition to surgical approaches, other interventions, such as cell transplantation, should be considered to keep the muscles in good condition until the axons regenerate. In this study, E14.5 rat embryonic spinal cord fetal cells and cultured neural progenitor cells from different spinal cord segments were injected into transected musculocutaneous nerve of 200-300 g female Sprague Dawley (SD) rats, and atrophy in biceps brachii was assessed. Both kinds of cells were able to survive, extend their axons towards the muscle and form neuromuscular junctions that were functional in electromyographic studies. As a result, muscle endplates were preserved and atrophy was reduced. Furthermore, we observed that the fetal cells had a better effect in reducing the muscle atrophy compared to the pure neural progenitor cells, whereas lumbar cells were more beneficial compared to thoracic and cervical cells. In addition, fetal lumbar cells were used to supplement six weeks delayed surgical repair after the nerve transection. Cell transplantation helped to preserve the muscle endplates, which in turn lead to earlier functional recovery seen in behavioral test and electromyography. In conclusion, we were able to show that embryonic spinal cord derived cells, especially the lumbar fetal cells, are beneficial in the treatment of peripheral nerve injuries due to their ability to prevent the muscle atrophy.


Assuntos
Atrofia Muscular/etiologia , Atrofia Muscular/patologia , Células-Tronco Neurais/citologia , Traumatismos dos Nervos Periféricos/complicações , Medula Espinal/citologia , Transplante de Células-Tronco , Animais , Astrócitos/metabolismo , Axônios/metabolismo , Biomarcadores , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Feminino , Neurônios Motores/metabolismo , Atrofia Muscular/reabilitação , Atrofia Muscular/terapia , Regeneração Nervosa , Células-Tronco Neurais/metabolismo , Junção Neuromuscular/citologia , Oligodendroglia/metabolismo , Fenótipo , Ratos , Recuperação de Função Fisiológica , Índice de Gravidade de Doença
5.
Regen Biomater ; 4(1): 21-30, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28149526

RESUMO

Peripheral nerves are fragile and easily damaged, usually resulting in nervous tissue loss, motor and sensory function loss. Advances in neuroscience and engineering have been significantly contributing to bridge the damage nerve and create permissive environment for axonal regrowth across lesions. We have successfully designed two self-assembling peptides by modifying RADA 16-I with two functional motifs IKVAV and RGD. Nanofiber hydrogel formed when combing the two neutral solutions together, defined as RADA 16-Mix that overcomes the main drawback of RADA16-I associated with low pH. In the present study, we transplanted the RADA 16-Mix hydrogel into the transected rat sciatic nerve gap and effect on axonal regeneration was examined and compared with the traditional RADA16-I hydrogel. The regenerated nerves were found to grow along the walls of the large cavities formed in the graft of RADA16-I hydrogel, while the nerves grew into the RADA 16-Mix hydrogel toward distal position. RADA 16-Mix hydrogel induced more axons regeneration and Schwann cells immigration than RADA16-I hydrogel, resulting in better functional recovery as determined by the gait-stance duration percentage and the formation of new neuromuscular junction structures. Therefore, our results indicated that the functional SAP RADA16-Mix nanofibrous hydrogel provided a better environment for peripheral nerve regeneration than RADA16-I hydrogel and could be potentially used in peripheral nerve injury repair.

6.
J Neurosci ; 36(19): 5193-9, 2016 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-27170118

RESUMO

UNLABELLED: Multiple sclerosis (MS) is a progressive autoimmune disease of the CNS with its underlying mechanisms not fully understood. In the present study, we tested the hypothesis that caveolin-1, a major membrane scaffolding protein, plays a critical role in the pathogenesis of experimental autoimmune encephalomyelitis, a laboratory murine model of MS. We found increased expression of caveolin-1 in serum and spinal cord tissues in association with disease incidence and severity in wild-type mice with active encephalomyelitis. After immunization, Cav-1 knock-out mice showed remarkable disease resistance with decreased incidence and clinical symptoms. Furthermore, Cav-1 knock-out mice had alleviated encephalitogenic T cells trafficking into the CNS with decreased expressions of adhesion molecules ICAM-1 and VCAM-1 within the lesions. In agreement with in vivo studies, in vitro knockdown of caveolin-1 compromised the upregulation of ICAM-1 in endothelial cells, leading to the amelioration of the transendothelial migration of pathogenic TH1 and TH17 cells. Together, those results indicate that caveolin-1 serves as an active modulator of CNS-directed lymphocyte trafficking and could be a therapeutic target for neuroinflammatory diseases, such as multiple sclerosis. SIGNIFICANCE STATEMENT: The hallmark feature of neuroinflammatory diseases is the massive infiltrations of encephalitogenic leukocytes into the CNS parenchyma, a process that remains largely unclear. Our study demonstrates the critical contribution of caveolin-1 to encephalomyelitis pathogenesis and CNS-directed lymphocyte trafficking by modulation of adhesion molecules ICAM-1 and VCAM-1, highlighting the pathological involvement of caveolin-1 in neuroinflammatory diseases.


Assuntos
Caveolina 1/metabolismo , Encefalomielite Autoimune Experimental/metabolismo , Medula Espinal/metabolismo , Linfócitos T/fisiologia , Migração Transendotelial e Transepitelial , Animais , Caveolina 1/genética , Células Cultivadas , Encefalomielite Autoimune Experimental/genética , Feminino , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
7.
Neuroscience ; 329: 213-25, 2016 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-27185485

RESUMO

Brachial plexus injury (BPI) often involves the complete or partial avulsion of one or more of the cervical nerve roots, which leads to permanent paralysis of the innervated muscles. Reimplantation surgery has been attempted as a clinical treatment for brachial plexus root avulsion but has failed to achieve complete functional recovery. Lithium is a mood stabilizer drug that is used to treat bipolar disorder; however, its effects on spinal cord or peripheral nerve injuries have also been reported. The purpose of this study was to investigate whether lithium can improve functional motor recovery after ventral root avulsion and reimplantation in a rat model of BPI. The results showed that systemic treatment with a clinical dose of lithium promoted motor neuron outgrowth and increased the efficiency of motor unit regeneration through enhanced remyelination. An analysis of myelin-associated genes showed that the effects of lithium started during the early phase of remyelination and persisted through the late stage of the process. Efficient remyelination of the regenerated axons in the lithium-treated rats led to an earlier functional recovery. Therefore, we demonstrated that lithium might be a potential clinical treatment for BPI in combination with reimplantation surgery.


Assuntos
Axônios/efeitos dos fármacos , Compostos de Lítio/farmacologia , Bainha de Mielina/efeitos dos fármacos , Regeneração Nervosa/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Raízes Nervosas Espinhais/efeitos dos fármacos , Animais , Axônios/patologia , Axônios/fisiologia , Plexo Braquial/efeitos dos fármacos , Plexo Braquial/lesões , Plexo Braquial/fisiopatologia , Plexo Braquial/cirurgia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/patologia , Neurônios Motores/fisiologia , Bainha de Mielina/patologia , Bainha de Mielina/fisiologia , Regeneração Nervosa/fisiologia , Distribuição Aleatória , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Recuperação de Função Fisiológica/fisiologia , Reimplante , Raízes Nervosas Espinhais/lesões , Raízes Nervosas Espinhais/fisiopatologia , Raízes Nervosas Espinhais/cirurgia
8.
Nanomedicine ; 11(3): 611-20, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24907463

RESUMO

There is no effective treatment for intracerebral hemorrhage (ICH). Intracerebral delivery of nanomaterials into the hemorrhagic lesion may be a new therapeutic strategy. In a rat model of ICH plus ultra-early hematoma aspiration, we found that locally delivered self-assembling peptide nanofiber scaffold (SAPNS) replaced the hematoma, reduced acute brain injury and brain cavity formation, and improved sensorimotor functional recovery. SAPNS serves as biocompatible material in the hemorrhagic brain cavity. Local delivery of this nanomaterial may facilitate the repair of ICH related brain injury and functional recovery. From the clinical editor: In a rat model of intracranial hemorrhage, these authors demonstrate that following ultra-early hematoma aspiration, local delivery of a self-assembling peptide nanofiber scaffold replaces the hematoma, reduces brain cavity formation, and improves sensorimotor functional recovery. Similar approaches would be welcome additions to the clinical treatment of this often devastating condition.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Hemorragias Intracranianas/tratamento farmacológico , Nanofibras/química , Peptídeos , Recuperação de Função Fisiológica/efeitos dos fármacos , Doença Aguda , Animais , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Modelos Animais de Doenças , Hemorragias Intracranianas/patologia , Hemorragias Intracranianas/fisiopatologia , Masculino , Peptídeos/química , Peptídeos/farmacologia , Ratos , Ratos Sprague-Dawley
9.
Biomed Res Int ; 2014: 658753, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24967390

RESUMO

Brachial plexus injury often involves traumatic root avulsion resulting in permanent paralysis of the innervated muscles. The lack of sufficient regeneration from spinal motoneurons to the peripheral nerve (PN) is considered to be one of the major causes of the unsatisfactory outcome of various surgical interventions for repair of the devastating injury. The present study was undertaken to investigate potential inhibitory signals which influence axonal regeneration after root avulsion injury. The results of the study showed that root avulsion triggered GSK-3ß activation in the injured motoneurons and remaining axons in the ventral funiculus. Systemic application of a clinical dose of lithium suppressed activated GSK-3ß in the lesioned spinal cord to the normal level and induced extensive axonal regeneration into replanted ventral roots. Our study suggests that GSK-3ß activity is involved in negative regulation for axonal elongation and regeneration and lithium, the specific GSK-3ß inhibitor, enhances motoneuron regeneration from CNS to PNS.


Assuntos
Axônios/enzimologia , Inibidores Enzimáticos/farmacologia , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Lítio/farmacologia , Neurônios Motores/enzimologia , Regeneração Nervosa/efeitos dos fármacos , Traumatismos dos Nervos Periféricos , Nervos Periféricos/enzimologia , Animais , Axônios/patologia , Ativação Enzimática , Feminino , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Neurônios Motores/patologia , Traumatismos dos Nervos Periféricos/tratamento farmacológico , Traumatismos dos Nervos Periféricos/enzimologia , Traumatismos dos Nervos Periféricos/patologia , Ratos , Ratos Sprague-Dawley , Raízes Nervosas Espinhais/enzimologia , Raízes Nervosas Espinhais/lesões
10.
BMC Surg ; 13: 21, 2013 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-23799915

RESUMO

BACKGROUND: Peripheral nerve (PN) transplantation and ventral root implantation are the two common types of recovery operations to restore the connection between motoneurons and their target muscles after brachial plexus injury. Despite experience accumulated over the past decade, fundamental knowledge is still lacking concerning the efficacy of the two microsurgical interventions. METHODS: Thirty-eight adult female Sprague-Dawley rats were divided into 5 groups. Immediately following root avulsion, animals in the first group (n = 8) and the second group (n = 8) received PN graft and ventral root implantation respectively. The third group (n = 8) and the fourth group (n = 8) received PN graft and ventral root implantation respectively at one week after root avulsion. The fifth group received root avulsion only as control (n = 6). The survival and axonal regeneration of severed motoneurons were investigated at 6 weeks post-implantation. RESULTS: Re-implantation of ventral roots, both immediately after root avulsion and in delay, significantly increased the survival and regeneration of motoneurons in the avulsed segment of the spinal cord as compared with PN graft transplantation. CONCLUSIONS: The ventral root re-implantation is a better surgical repairing procedure than PN graft transplantation for brachial plexus injury because of its easier manipulation for re-implanting avulsed ventral roots to the preferred site, less possibility of causing additional damage and better effects on motoneuron survival and axonal regeneration.


Assuntos
Plexo Braquial/cirurgia , Microcirurgia/métodos , Neurônios Motores/fisiologia , Regeneração Nervosa , Nervos Periféricos/transplante , Reimplante , Raízes Nervosas Espinhais/cirurgia , Animais , Axônios/fisiologia , Plexo Braquial/lesões , Plexo Braquial/fisiologia , Feminino , Ratos Sprague-Dawley , Raízes Nervosas Espinhais/lesões , Raízes Nervosas Espinhais/fisiologia
11.
Stem Cell Res ; 11(1): 529-39, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23578695

RESUMO

Induced pluripotent stem cells (iPSCs) hold promise for the treatment of motoneuron diseases because of their distinct features including pluripotency, self-derivation and potential ability to differentiate into motoneurons. However, it is still unknown whether human iPSC-derived motoneurons can functionally innervate target muscles in vivo, which is the definitive sign of successful cell therapy for motoneuron diseases. In the present study, we demonstrated that human iPSCs derived from mesenchymal cells of the umbilical cord possessed a high yield in neural differentiation. Using a chemically-defined in vitro system, human iPSCs efficiently differentiated into motoneurons which displayed typical morphology, expressed specific molecules, and generated repetitive trains of action potentials. When transplanted into the injured musculocutaneous nerve of rats, they survived robustly, extended axons along the nerve, and formed functional connections with the target muscle (biceps brachii), thereby protecting the muscle from atrophy. Our study provides evidence for the first time that human iPSC-derived motoneurons are truly functional not only in vitro but also in vivo, and they have potential for stem cell-based therapies for motoneuron diseases.


Assuntos
Doença dos Neurônios Motores/terapia , Neurônios Motores/transplante , Músculo Esquelético/inervação , Células-Tronco Pluripotentes/citologia , Animais , Diferenciação Celular/fisiologia , Feminino , Humanos , Imuno-Histoquímica , Neurônios Motores/citologia , Neurônios Motores/fisiologia , Ratos , Ratos Sprague-Dawley
12.
Cell Transplant ; 21(12): 2651-63, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22963797

RESUMO

Neural progenitor cells (NPCs) are suggested to be a valuable source of cell transplant in treatment of various neurological diseases because of their distinct attributes. They can be expanded and induced to differentiate in vitro. However, it remains uncertain whether in vitro expanded NPCs have the capacity to give rise to functional motoneurons after transplantation in vivo. Here, we showed that in vitro expanded NPCs, when transplanted into the musculocutaneous nerve, generated motoneuron-like cells that exhibited typical morphology with large cell bodies, expressed specific molecules, and extended axons to form functional connections with the target muscle. In contrast, transplanted NPCs failed to yield motoneurons in the injured ventral horn of the spinal cord. The results of the study demonstrate that NPCs have the potential to generate functional motoneurons in an appropriate environment. The distinct differentiating fate of NPCs in the musculocutaneous nerve and the injured ventral horn suggests the importance and necessity of modifying the host microenvironment in use of NPCs for cell replacement therapies for motoneuron diseases.


Assuntos
Neurônios Motores/citologia , Nervo Musculocutâneo/fisiologia , Células-Tronco Neurais/transplante , Animais , Células do Corno Anterior/fisiopatologia , Diferenciação Celular , Células Cultivadas , Feminino , Imuno-Histoquímica , Doença dos Neurônios Motores/terapia , Neurônios Motores/metabolismo , Atrofia Muscular/patologia , Atrofia Muscular/terapia , Células-Tronco Neurais/citologia , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/terapia
13.
Exp Gerontol ; 47(4): 329-36, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22382134

RESUMO

Post-injury nerve regeneration of the peripheral nervous system declines with age, but the mechanisms underlying the weakened axonal regeneration are not well understood. Increased synthesis and activity of the AP-1 transcription factor c-Jun have been implicated in efficient motor axonal regeneration. In the present study, we evaluated the hypothesis that the impaired regenerative capacity in the aged is associated with impaired induction of c-Jun. In non-manipulated young adult or aged mice, no c-Jun and its phosphorylated form were detected in the ventral horn of the spinal cord. Following nerve crush, significant c-Jun and phosphorylated c-Jun occurred in the injured motoneurons of young adult mice, but not in aged animals. In accord with the immunohistochemistry, Western blots also showed that sciatic nerve crush induced c-Jun and its phosphorylation expression in the ventral horn of young adult but not in aged mice. Changes in c-Jun mRNA level detected by in situ hybridization are congruent with that in c-Jun protein content, showing an increase at 5 days after crush in young adult but not aged. Moreover, compared with young adult mice, aged mice showed impaired motor axonal regeneration. These results demonstrate that the impaired motor axonal regeneration seen in aged mice is correlated with impaired c-Jun expression and phosphorylation following injury. These data provide a neurobiological explanation for the poor outcome associated with nerve repair in the aged.


Assuntos
Envelhecimento/fisiologia , Neurônios Motores/fisiologia , Regeneração Nervosa/fisiologia , Proteínas Proto-Oncogênicas c-jun/fisiologia , Nervo Isquiático/lesões , Envelhecimento/metabolismo , Animais , Axônios/fisiologia , Feminino , Regulação da Expressão Gênica/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios Motores/metabolismo , Compressão Nervosa , Fosforilação/fisiologia , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , RNA Mensageiro/genética , Nervo Isquiático/fisiologia , Medula Espinal/metabolismo , Medula Espinal/patologia , Medula Espinal/fisiologia
14.
J Neuropathol Exp Neurol ; 68(1): 94-101, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19104442

RESUMO

We previously showed that motor nerves are superior to sensory nerves in promoting axon regeneration after spinal root avulsion. It is, however, impractical to use motor nerves as grafts. One potential approach to enhancing axonal regeneration using sensory nerves is to deliver trophic factors to the graft. Here, we examined the regulation of receptors for brain-derived neurotrophic factor, glial cell line-derived neurotrophic factor, ciliary neurotrophic factor, and pleiotrophin after root avulsion in adult rats. We then tested their survival-promoting and neuroregenerative effects on spinal motoneurons. The results showed that receptors for brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor were upregulated and that these trophic factors promoted survival and axonal regeneration of motoneurons when they were injected into the sensory nerve graft before implantation. In contrast, receptors for ciliary neurotrophic factor and pleiotrophin were downregulated after avulsion. Ciliary neurotrophic factor did not promote survival and axonal regeneration, whereas pleiotrophin promoted axonal regeneration but not survival of injured spinal motoneurons. Our results suggest that infusion of trophic factors into sensory nerve grafts promote motoneuron survival and axonal regeneration. The technique is technically easy and is, therefore, potentially clinically applicable.


Assuntos
Neurônios Motores/fisiologia , Regeneração Nervosa/fisiologia , Nervos Periféricos/citologia , Nervos Periféricos/transplante , Radiculopatia/patologia , Radiculopatia/cirurgia , Animais , Sobrevivência Celular/fisiologia , Modelos Animais de Doenças , Masculino , Neurônios Motores/efeitos dos fármacos , Fatores de Crescimento Neural/farmacologia , Fatores de Crescimento Neural/uso terapêutico , Regeneração Nervosa/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores de Fatores de Crescimento/metabolismo , Estilbamidinas , Fatores de Tempo
15.
Hepatology ; 46(3): 690-8, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17680649

RESUMO

UNLABELLED: Recently, controversies have arisen about whether hepatitis B e antigen (HBeAg) seroconversion can result in regression of fibrosis, thus improving the clinical outcome of Chinese patients with chronic hepatitis B. In this study, we determined if spontaneous HBeAg seroconversion is associated with regression of fibrosis in Chinese chronic hepatitis B patients. We evaluated the histology of liver samples from 128 HBeAg-positive treatment-naive Chinese patients who had undergone 2 liver biopsies over the years. Regression of fibrosis was defined as a decrease in fibrosis stage of at least 1 point. Sustained disease remission was defined as HBeAg seroconversion and hepatitis B virus (HBV) DNA < 10(4) copies/ml at follow-up liver biopsy. The mean duration (+/- standard error of the mean) between the initial and follow-up liver biopsies was 43.9 +/- 3.4 months. Regression of fibrosis was higher in patients with sustained disease remission (5 of 13 [38.5%] versus 22 of 115 [19.1%], P < 0.00005), patients who were younger (20-29 years old) at initial liver biopsy (17 of 54 [31.5%] versus 10 of 74 [13.5%], P = 0.0004), and patients with genotype B (17 of 43 [39.5%] versus 10 of 85 [11.8%], P = 0.004). On multivariate analysis, sustained disease remission (relative risk [RR] 3.00, 95% confidence interval [95% CI] 1.29-7.01, P = 0.01) and being 20-29 years old at initial liver biopsy (RR 2.94, 95% CI 1.01-8.62, P = 0.04) were independently associated with regression of fibrosis. The rate of fibrosis progression was lower in patients with sustained disease remission than in those who remained HBeAg positive (median 0 fibrosis units/year, range -2.00 to -0.70 fibrosis units/year, versus median 0.51 fibrosis units/year, range 0 to +2.03 fibrosis units/year, P = 0.02). CONCLUSION: Spontaneous sustained remission of disease is associated not only with little progression of fibrosis but also with regression of fibrosis.


Assuntos
Anticorpos Anti-Hepatite B/sangue , Antígenos E da Hepatite B/imunologia , Hepatite B Crônica/diagnóstico , Adulto , Povo Asiático , Biomarcadores/sangue , DNA Viral/sangue , Progressão da Doença , Feminino , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Remissão Espontânea , Replicação Viral
16.
Hepatology ; 46(2): 395-401, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17628874

RESUMO

UNLABELLED: In view of the findings that high hepatitis B virus (HBV) deoxyribonucleic acid (DNA) is associated with increased risk of chronic hepatitis B (CHB)-related complications, disease progression in CHB patients in the immune-tolerant phase is uncertain. We evaluated disease progression in 57 immune-tolerant CHB patients with high HBV DNA. Each subject underwent an initial liver biopsy. In those who remained in the immune-tolerant phase, a follow-up liver biopsy was performed after 5 years of follow-up. Patients who developed elevated serum alanine aminotransferase (ALT) levels were discontinued from the study after a follow-up liver biopsy. Disease progression was defined as a 1-point increase in fibrosis stage. Initial liver biopsies showed the median fibrosis stage of the study patients was 1 (range 0-1). By the end of follow-up, 9 of the 57 patients (15.8%) had developed elevated serum ALT. In those who remained in the immune-tolerant phase, follow-up fibrosis stage was comparable with the initial fibrosis stage (P = 0.58). However, disease progression was greater in patients who developed elevated serum ALT when compared with those who remained in the immune-tolerant phase (5 of 9 vs. 3 of 48, respectively, P = 0.001). The median rate of fibrosis progression of patients who remained in the immune-tolerant phase was lower than that of patients with high serum ALT (0 U/year [range -0.40-0.20 U/year] versus 0.21 U/year [range 0-1.11 U/year], respectively, P = 0.04). CONCLUSION: CHB patients in the immune-tolerant phase have mild disease. In those who remained in the immune-tolerant phase in the present study, disease progression was minimal. However, immune-tolerant patients who progressed to the immune clearance phase often faced disease progression.


Assuntos
Hepatite B Crônica/complicações , Adolescente , Adulto , Alanina Transaminase/sangue , DNA Viral/sangue , Progressão da Doença , Feminino , Seguimentos , Antígenos E da Hepatite B/análise , Hepatite B Crônica/imunologia , Hepatite B Crônica/patologia , Humanos , Tolerância Imunológica , Fígado/patologia , Masculino
17.
J Gastroenterol Hepatol ; 22(1): 137-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17201898

RESUMO

A patient is reported with intestinal tuberculosis that mimicked fistulizing Crohn's disease endoscopically. He had complete resolution of symptoms after a full course of antituberculosis therapy. Gastroenterologists and general physicians should aware of the possibility of intestinal tuberculosis in areas with a high prevalence of tuberculosis infection.


Assuntos
Antituberculosos/uso terapêutico , Fístula Intestinal/diagnóstico , Tuberculose Gastrointestinal/diagnóstico , Tuberculose Gastrointestinal/tratamento farmacológico , Meios de Contraste , Doença de Crohn/diagnóstico , Diagnóstico Diferencial , Humanos , Lactente , Fístula Intestinal/tratamento farmacológico , Fístula Intestinal/microbiologia , Masculino , Tomografia Computadorizada por Raios X
18.
Atherosclerosis ; 192(2): 266-74, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16945374

RESUMO

Apolipoprotein A-IV (apoA-IV) inhibits lipid peroxidation, thus demonstrating potential anti-atherogenic properties. The aim of this study was to investigate how the inhibition of low density lipoprotein (LDL) oxidation was influenced by common apoA-IV isoforms. Recombinant wild type apoA-IV (100 microg/ml) significantly inhibited the oxidation of LDL (50 microg protein/ml) by 5 microM CuSO(4) (P<0.005), but not by 100 microM CuSO(4), suggesting that it may act by binding copper ions. ApoA-IV also inhibited the oxidation of LDL by the water-soluble free-radical generator 2,2'-azobis(amidinopropane) dihydrochloride (AAPH; 1 mM), as shown by the two-fold increase in the time for half maximal conjugated diene formation (T(1/2); P<0.05) suggesting it can also scavenge free radicals in the aqueous phase. Compared to wild type apoA-IV, apoA-IV-S347 decreased T(1/2) by 15% (P=0.036) and apoA-IV-H360 increased T(1/2) by 18% (P=0.046). All apoA-IV isoforms increased the relative electrophoretic mobility of native LDL, suggesting apoA-IV can bind to LDL and acts as a site-specific antioxidant. The reduced inhibition of LDL oxidation by apoA-IV-S347 compared to wild type apoA-IV may account for the previous association of the APOA4 S347 variant with increased CHD risk and oxidative stress.


Assuntos
Apolipoproteínas A/genética , Apolipoproteínas A/fisiologia , Lipoproteínas LDL/metabolismo , Amidinas/química , Antioxidantes/farmacologia , Apolipoproteína A-V , Sulfato de Cobre/química , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Mutagênese Sítio-Dirigida , Oxirredução , Isoformas de Proteínas/fisiologia
19.
Am J Gastroenterol ; 101(11): 2463-9, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17090277

RESUMO

BACKGROUND: Patients with nonerosive reflux disease (NERD) have the lowest esophageal acid exposure profile compared with the other gastroesophageal reflux disease (GERD) groups. AIM: To compare lower esophageal acid exposure recordings 1 cm above the lower esophageal sphincter (LES) with those 6 cm above the LES as well as to determine the characteristics of esophageal acid exposure along the esophagus among the different GERD groups. METHODS: Patients with classic heartburn symptoms were enrolled into the study. Patients were evaluated by a demographics questionnaire and the validated GERD Symptom Checklist. Upper endoscopy was performed to evaluate the presence of esophageal erosions and Barrett's esophagus (BE). Ambulatory pH testing was performed using a commercially available 4-sensor pH probe with sensors located 5 cm apart. The distal sensor was placed 1 cm above the LES. RESULTS: Sixty-four patients completed the study. Of those, 21 patients had NERD, 20 had erosive esophagitis (EE), and 23 had BE. All patient groups demonstrated greater esophageal acid exposure 1 cm above the LES than 6 cm above the LES. In NERD and EE, this phenomenon was primarily a result of a higher mean percentage of upright time with pH <4. Unlike patients with EE and BE, those with NERD had very little variation in esophageal acid exposure throughout the esophagus (total and supine). CONCLUSIONS: ALL GERD groups demonstrated significant greater esophageal acid exposure at the very distal portion of the esophagus, primarily as a result of short upright reflux events. Unlike erosive esophagitis and BE, NERD patients demonstrate a more homogenous acid distribution along the esophagus.


Assuntos
Ácido Gástrico/metabolismo , Refluxo Gastroesofágico/patologia , Adulto , Idoso , Esôfago de Barrett/complicações , Esofagite/patologia , Esofagoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Consult Clin Psychol ; 74(5): 870-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17032091

RESUMO

In this study, the authors examined perceived benefits and costs of the outbreak of severe acute respiratory syndrome (SARS). Mixed accounts of benefits and costs, rather than exclusive accounts of only benefits or costs, were proposed to be characterized by nondefensiveness and enduring changes in psychosocial resources. Participants were 70 SARS recoverers, 59 family members of SARS recoverers, and 172 healthy adults residing in Hong Kong--a SARS-affected region. Results show that participants giving an exclusive account of benefits had higher levels of defensiveness than those giving a mixed account and those giving an exclusive account of costs. Only the perceived impact of benefits given in mixed accounts were related to future accruements in personal and social resources over an 18-month period.


Assuntos
Surtos de Doenças , Síndrome Respiratória Aguda Grave/economia , Síndrome Respiratória Aguda Grave/epidemiologia , Adulto , Análise Custo-Benefício , Feminino , Hong Kong/epidemiologia , Humanos , Masculino , Estudos Prospectivos , Inquéritos e Questionários , Fatores de Tempo
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