Research status and prospect of remyelination in multiple sclerosis based on "inflammation-tissue" homeostatic coupling / 中国中药杂志

Multiple sclerosis(MS) shows the pathological characteristics of "inflammatory injury of white matter" and "myelin repair disability" in the central nervous system(CNS). It is very essential for MS treatment and reduction of disease burden to strengthen repair, improve function, and reduce disability. Accordingly, different from the simple immunosuppression, we believe that key to strengthening remyelination and maintaining the "damage-repair" homeostasis of tissue is to change the current one-way immunosuppression strategy and achieve the "moderate pro-inflammation-effective inflammation removal" homeostasis. Traditional Chinese medicine shows huge potential in this strategy. Through literature research, this study summarized the research on remyelination, discussed the "mode-rate pro-inflammation-effective inflammation removal" homeostasis and the "damage-repair" homeostasis based on microglia, and summed up the key links in remyelination in MS. This review is expected to lay a theoretical basis for improving the function of MS patients and guide the application of traditional Chinese medicine.

Hypomyelinogenesis associated with transplacental poisoning by Sida carpinifolia (Malvaceae) in fetus and newborn calves / Hipomielinogênese associada à intoxicação transplacentária por Sida carpinifolia (Malvaceae) em fetos e neonatos bovinos

Sida carpinifolia is a plant responsible for poisoning several species of animals. This paper describes Hypomyelinogenesis in fetuses and neonates of cattle that consumed S. carpinifolia. Neonates manifested ataxia and muscle tremors. Two bovine newborns and four fetuses were necropsied and showed no significant gross changes. Histopathologic findings included vacuolation of pancreatic acinar cells, thyroid follicular cells, hepatocytes, cells of renal tubules and neurons of the fetus and the white matter of the telencephalic frontal lobe of the neonates and also revealed axonal spheroids in the brain of the fetuses and neonates. The lectin-histochemical evaluation shoved staining for the lectins Con-A, WGA and s-WGA. The Luxol Fast Blue staining revealed a marked decrease of myelin in the brain of all the fetuses and a moderate decrease in the neonates. Histologic and lectin-histochemic findings indicate that the consumption of S. carpinifolia by pregnant bovine females can cause hypomyelinogenesis in fetuses and neonates.(AU)

Sida carpinifolia é uma planta responsável por intoxicar várias espécies animais. Este artigo descreve hipomielinogênese em fetos e neonatos de bovinos que consumiram S. carpinifolia. Os neonatos manifestaram ataxia e tremores musculares. Dois neonatos e quatro fetos bovinos foram necropsiados e não havia alterações macroscópicas significativas. Os achados histopatológicos incluíram vacuolização de células acinares do pâncreas, células foliculares da tireoide, hepatócitos, células renais tubulares e neurônios nos fetos. Nos neonatos havia vacuolização na substância branca do lobo frontal telencefálico, além de esferoides axonais no encéfalo dos fetos e dos recém-nascidos. A avaliação lectino-histoquímica demonstrou marcação para as lectinas Con-A, WGA e s-WGA. A coloração de Luxol Fast Blue revelou diminuição acentuada da mielina no telencéfalo de todos os fetos e diminuição moderada nos neonatos. Os achados histológicos e lectina-histoquímicos indicam que o consumo de S. carpinifolia por fêmeas bovinas gestantes pode causar hipomielinogênese em fetos e neonatos.(AU)

Degenerative axonopathy associated with copper deficiency in pigs / Axonopatia degenerativa associada com deficiência de cobre em suínos

The epidemiological, clinic and morphological (pathological and ultrastructural) aspects of four outbreaks of copper deficiency affecting 21- to 90-day-old pigs in the Northeast region of Brazil are reported. Clinical signs began with paraparesis and ataxia and progressed to flaccid or spastic paralysis of the pelvic and thoracic limbs, followed by sternal and/or lateral recumbence. In addition, some animals showed dog-sitting position and intention tremors. The clinical manifestation period was 5-20 days. Significant gross lesions were not observed; however, microscopically, symmetrical degeneration of the white matter with ballooned myelin sheaths containing occasional macrophages was observed, mainly in the spinal cord. Two pigs presented with necrosis ad loss of Purkinje cells and ectopic Purkinje cells in the granular layer and cerebellar white matter. A ultrastructural analysis showed different degrees of damage of myelinated axons in the spinal segments, including an absence of the axoplasm structures with only axonal residues remaining. The myelin sheaths were degenerated and often collapsed into the space previously occupied by the axon. These results suggest that myelin degeneration is secondary to the axonal lesion. Finally, the concentration of copper in the liver was determined using atomic absorption spectrophotometry and was found to be low (ranging from 2.2 to 10.8 ppm). In conclusion, in the Brazilian semiarid region, Cu deficiency occurs in 21 to 90-day-old pigs that ingested different types of waste in their food.(AU)

São relatados os achados epidemiológicos, clínicos e morfológicos (patológicos e ultraestruturais) de quatro surtos de deficiência de cobre em suínos afetados entre 21 e 90 dias de idade na região Nordeste do Brasil. Os sinais clínicos iniciaram com paraparesia e ataxia, que progrediu a paralisia flácida ou espástica dos membros pélvicos e torácicos, seguido de decúbito esternal e/ou lateral. Além disso, alguns animais apresentaram posição de cão sentado e tremores de intenção. O período de manifestação clínica variou de 5-20 dias. Não foram observadas lesões macroscópicas significativas; no entanto, microscopicamente, foi observada degeneração simétrica da substância branca com fragmentação das bainhas de mielina, contendo ocasionais macrófagos, principalmente na medula espinal. Dois suínos apresentaram necrose e perda de células de Purkinje e células de Purkinje ectópicos na camada granular da substância branca cerebelar. A análise ultraestrutural mostrou diferentes graus de lesões em axônios mielinizados em segmentos da medula espinhal, incluindo o desaparecimento de estruturas do axoplasma, restando apenas restos axonais. A bainha de mielina encontrava-se degenerada e muitas vezes, colapsada dentro do espaço previamente ocupado pelo axônio. Esses resultados sugerem que a degeneração da mielina é secundária à lesão axonal. Finalmente, a concentração do cobre no fígado foi determinada usando espectrometria de absorção atômica e revelou baixos valores (variando de 2,2-10,8ppm). Conclui-se que na região semiárida do Brasil ocorre deficiência de cobre em suínos de 21 a 90 dias de idade alimentados com diferentes tipos de resíduos.(AU)

Neurorrhaphy techniques: comparative stereological and experimental axonal study / Técnicas de neurorrafia: estudio experimental estereológico axonal comparativo

There is a great variety of injuries that affect peripheral nerves derived from acquired or congenital degenerative diseases affecting the central nervous system that cause loss of sensorimotor functions. The objective of this work was to perform an end-to-side or side-to-side experimental axonal stereological study in order to compare volume density of axons, endouneuro and myelin sheath (and muscle mass) in peroneal and tibial nerves, with anastomosis contact from 0.25 cm to 0.50 cm. After approval of the Ethics Committe, 20 male Wistar rats were divided into four groups of five rats each (G1= end-to-side neurorrhaphy; G2= side-to-side neurorrhaphy of 0.25 cm; G3= side-to-side neurorrhaphy of 0 cm and G4= Control of normality). After 180 days, fragments of peroneal and tibial nerves were collected for histological and stereological study. In comparative stereological experimental study between neurorraphies, the volume density of axons, myelin sheath of tibial and fibular nerves, as well as the post-surgical muscle mass, remains the same in end-to-side and side-to-side neurorraphies, regardless of contact area of anastomosis. It can be inferred, as surgical repair options, both end-to-side neurorrhaphy to recover and prevents atrophy of the endplate as side-to-side neurorraphy that is independent of the distance between the nerve stumps.

Gran variedad de lesiones atingen a los nervios periféricos, derivadas de enfermedades adquiridas o degenerativas congénitas que afectan la parte central del sistema nervioso y que ocasionan pérdida de funciones sensoriomotoras. El objetivo de ese trabajo fue realizar un estudio experimental estereológico axonal post neurorrafias termino-lateral o latero-lateral para comparar densidad de volumen de axones, endoneuro y vaina de mielina (así como masa muscular) en nervios fibular y tibial, con unión de contacto entre 0,25 cm y 0,50 cm. Tras la aprobación del comité de ética, fueran utilizados 20 ratones machos de la raza Wistar divididos en cuatro grupos de 5 ratones cada uno (G1= Neurorrafia término lateral; G2= Neurorrafia latero lateral de 0,25 cm; G3= Neurorrafia latero lateral de 0,50 cm y G4= Control). Posteriormente, fragmentos de los nervios tibiales y fibulares fueron procesados para estudios histológicos y estereológicos. En el estudio experimental estereológico comparativo entre neurorrafias termino-lateral y latero-lateral, la densidad de volumen de axones, endoneuro y vaina de mielina de nervios tibial y fibular y también la masa muscular post quirúrgica se mantuvo equitativa, independientemente del área de unión de contacto. Podemos inferir como opciones de reparación quirúrgica, que el tratamiento de la neurorrafia termino-lateral y latero-lateral previnen la atrofia de placa motora, independiente de la distancia entre los muñones nerviosos.

Adult mesenchymal stem cell therapy for myelin repair in Multiple Sclerosis

Multiple sclerosis (MS) is a demyelinating immune-mediated disease of the central nervous system (CNS). It is the most frequent neurological disease in young adults and affects over 2 million people worldwide. Current treatments reduce the relapse rate and the formation of inflammatory lesions in the CNS, but with only temporary and limited success. Despite the presence of endogenous oligodendroglial progenitors (OPCs) and of spontaneous remyelination, at least in early MS its levels and its qualities are apparently insufficient for a sustained endogenous functional repair. Therefore, novel MS therapies should consider not only immunemodulatory but also myelin repair activities. Mesenchymal stem cells (MSCs) represent an attractive alternative to develop a cell-based therapy for MS. MSCs display stromal features and exert bystander immunemodulatory and neuroprotective activities. Importantly, MSCs induce oligodendrocyte fate decision and differentiation/maturation of adult neural progenitors, suggesting the existence of MSC-derived remyelination activity. Moreover, transplanted MSCs promote functional recovery and myelin repair in different MS animal models. Here, we summarize the current knowledge on endogenous mechanisms for remyelination and proposed autologous MSC therapy as a promising strategy for MS treatment.

GM1 improves neurofascin155 association with lipid rafts and prevents rat brain myelin injury after hypoxia-ischemia

White matter injury characterized by damage to myelin is an important process in hypoxic-ischemic brain damage (HIBD). Because the oligodendrocyte-specific isoform of neurofascin, neurofascin 155 (NF155), and its association with lipid rafts are essential for the establishment and stabilization of the paranodal junction, which is required for tight interaction between myelin and axons, we analyzed the effect of monosialotetrahexosyl ganglioside (GM1) on NF155 expression and its association with lipid rafts after HIBD in Sprague-Dawley rats, weighing 12-15 g, on day 7 post-partum (P7; N = 20 per group). HIBD was induced on P7 and the rats were divided into two groups: one group received an intraperitoneal injection of 50 mg/kg GM1 three times and the other group an injection of saline. There was also a group of 20 sham-operated rats. After sacrifice, the brains of the rats were removed on P30 and studied by immunochemistry, SDS-PAGE, Western blot analysis, and electron microscopy. Staining showed that the saline group had definite rarefaction and fragmentation of brain myelin sheaths, whereas the GM1 group had no obvious structural changes. The GM1 group had 1.9-2.9-fold more GM1 in lipid rafts than the saline group (fraction 3-6; all P < 0.05) and 0.5-2.4-fold higher expression of NF155 in lipid rafts (fraction 3-5; all P < 0.05). Injection of GM1 increased the content of GM1 in lipid rafts as well as NF155 expression and its lipid raft association in HIBD rat brains. GM1 may repair the structure of lipid rafts, promote the association of NF155 (or other important proteins) with lipid rafts, stabilize the structure of paranodes, and eventually prevent myelin sheath damage, suggesting a novel mechanism for its neuroprotective properties.

Anti-inflammatory effect of the epigallocatechin gallate following spinal cord trauma in rat

Spinal cord injury [SCI] stimulates an inflammatory reaction that causes substantial secondary damage inside the injured spinal tissue. The purpose of this study was to determine the anti-inflammatory effects of epigallocatechin gallate [EGCG] on traumatized spinal cord. Methods: Rats were randomly divided into four groups of 12 rats each as follow: sham-operated group, trauma group, and EGCG-treatment groups [50 mg/kg, i.p., immediately and 1 hour after SCI]. Spinal cord samples were taken 24 hours after injury and studied for determination of myeloperoxidase [MPO] activity, histopathological assessment and immunohistochemistry of tumor necrosis factor-a [TNF-alpha], interleukin-1 beta [IL-1beta], Nitrotyrosine, inducible nitric oxide synthase [iNOS], cyclooxygenase-2 [COX-2], and poly [ADP-ribose] polymerase [PARP]. The results showed that MPO activity was significantly decreased in EGCG-treatment groups. Attenuated TNF-alpha, IL-1beta, Nitrotyrosine, iNOS, COX-2, and PARP expression could be detected in the EGCG treated rats. Also, EGCG attenuated myelin degradation. On the basis of these findings, we propose that EGCG may be effective in protecting rat spinal cord from secondary damage by modulating the inflammatory reactions

C3c intrathecal synthesis evaluation in patients with multiple sclerosis

INTRODUCTION: Multiple sclerosis (MS) is a chronic, inflammatory and progressive disease of the central nervous system in which local inflammatory injuries of the brain white matter appears, being the most outstanding feature the myeline loss (demyelination). OBJECTIVE: To determine if the complement system might be involved in the MS immunopathogeny favouring the mechanism intervening in the myelin destruction. METHOD: Samples of sera and CSF from twelve patients with a diagnosis of MS obtained at the moment of the admission to the hospital at the beginning of the break out, were collected. Levels of C3c and albumin in sera and in CSF were quantified using radial immunodiffusion plates. RESULTS: High values over 80 percent of intrathecal synthesis were obtained except in one of the patients. CONCLUSION: Intrathecal synthesis of C3c and its liberation to the CSF means that the activation of the complement system in any of the two ways has taken place, and that once performed its biological functions, has suffered a degradation process.

INTRODUCCION: La esclerosis múltiple (EM) es una enfermedad crónica, inflamatoria y progresiva del sistema nervioso central que cursa con la aparición de lesiones inflamatorias focales en la sustancia blanca cerebral, en las que lo más llamativo es la pérdida de mielina (desmielinización). OBJETIVO: Conocer si el sistema de complemento puede estar involucrado en la inmunopatogenia de la EM favoreciendo los mecanismos que median la destrucción de la mielina. MÉTODO: Se colectaron muestras de suero y LCR de doce pacientes con diagnóstico de EM obtenidas en el momento del ingreso al inicio del brote. Se cuantificaron los niveles de C3c y albúmina en suero y en LCR en placas de inmunodifusión radial. RESULTADOS: Se obtuvieron altos valores que superan el 80 por ciento de síntesis intratecal, menos en uno de los pacientes. CONCLUSION: La síntesis intratecal de C3c y su liberación al LCR significa que ha sucedido la activación del sistema de complemento en alguna de las dos vías y que una vez cumplidas sus funciones biológicas, ha sufrido un proceso de degradación y liberación al LCR en forma de C3c.

Modelo experimental comportamental e histológico da regeneração do nervo facial em ratos / Behavioral and histologic experimental model of facial nerve regeneration in rats

O estabelecimento de modelos experimentais é o passo inicial para estudos de regeneração neural. OBJETIVO: Estabelecer modelo experimental de regeneração do nervo facial. MATERIAIS E MÉTODOS: Ratos Wistar com secção completa e sutura do tronco do nervo facial extratemporal, com análise comportamental e histológica até 9 semanas. FORMA DE ESTUDO: Estudo prospectivo experimental. RESULTADOS: Progressiva recuperação clínica e histológica dos animais. CONCLUSÃO: Estabelecemos um método aceitável para o estudo de regeneração do nervo facial em ratos.

To setup an experimental model is the first step to study neural regeneration. AIM: Setting up an experimental model on facial nerve regeneration. MATERIAL AND METHODS Wistar rats with complete sectioning and suturing of the extratemporal facial nerve trunk; with a behavioral and histological analysis for 9 weeks. STUD DESIGN: Experimental prospective study. RESULTS: Progressive clinical and histological recovery of the animals. CONCLUSION: Our method is acceptable to study facial nerve regeneration in rats.

Regeneração pós-traumática do nervo facial em coelhos / Posttraumatic facial nerve regeneration in rabbits

A paralisia facial periférica traumática constitui-se em afecção freqüente. OBJETIVO: estudo da regeneração pós-traumática do nervo facial em coelhos, por avaliação funcional histológica dos nervos traumatizados comparados aos normais contralaterais. METODOLOGIA: Vinte coelhos foram submetidos à compressão do tronco do nervo facial esquerdo e sacrificados após duas (grupo AL), quatro (BL) e seis (CL) semanas da lesão. A comparação entre os grupos foi feita pelas densidades total e parcial de axônios mielinizados. ESTUDO ESTATíSTICO: método de Tukey (p < 0,05). RESULTADOS: Houve recuperação funcional parcial após duas, e completa após cinco semanas. Na análise qualitativa, verificou-se em AL um padrão degenerativo, com maior processo inflamatório tecidual. Em BL, sinais de regeneração neural, praticamente completa em CL. Os nervos normais (N) apresentaram DT média de 15705,59 e DP média de 21800,75. O grupo BL revelou DT média de 10818,55 e DP média de 15340,56 e o CL, DT média de 13920,36 e DP média de 16589,15. BL obteve 68,88 por cento, e o grupo CL, 88,63 por cento da DT de N. N mostrou DP maior que os lesados; porém, esta não evidenciou diferença estatística entre BL e CL. A DT dos nervos revelou-se um método analítico mais fidedigno do que a DP estudada.

Posttraumatic facial paralysis is a frequent disease. This work studies posttraumatic regeneration of the facial nerve in rabbits. Functional and histological analysis compared injured and normal nerves on opposite sides. The left facial nerve trunk of twenty rabbits were subjectedto compression lesion, and sacrificed after two (subgroup AL), four (BL) and six (CL) weeks. Comparison between groups was made by analysing total and partial densities of myelinated axons. STATISTICAL ANALYSIS: Tukey Method (p<0.05). RESULTS:There was partial functional recovery after two weeks, and complete recovery after five weeks. Qualitative analysis demonstrated a degenerative pattern in the AL group, with an increased tissue inflammatory process. Evident regeneration signs were observed in the BL group, and almost complete regeneration was seen in the CL group. Normal nerves (N) had an average TD of 15705.59 and average PD of 21800.75. The BL group had an average TD of 10818.55 and an average PD of 15340.56. The CL group had an average TD of 13920.36 and an average PD of 16589.15. The BL group had an average TD of N equal to 68.88 percent, and the CL group had an average TD of N equal to 88,63 percent (statistically significant). N showed a significant higher PD than injured nerves. However, this was not statistically different between BL and CL subgroups. Nerve DT was a more reliable method than PD in this study.

Avaliação da atividade locomotora após indução local de desmielinização tóxica no tronco encefálico de ratos Wistar / Evaluation of locomotor activity after a local induction of toxic demyelination in the brainstem of Wistar rats

Lesões desmielinizantes induzidas pelo gliotóxico brometo de etídio (BE) têm sido estudadas com o objetivo de permitir a compreensão do limitado processo de reparo mielínico no sistema nervoso central, bem como avaliar estratégias terapêuticas no sentido de acelerar a reconstrução das bainhas de mielina perdidas. Muito embora estudos eletrofisiológicos correlacionando situações de desmielinização e remielinização experimental sejam bem estabelecidos, os efeitos comportamentais não têm sido adequadamente investigados. Neste estudo, foram analisadas ultra-estruturalmente as lesões desmielinizantes e a atividade locomotora de ratos submetidos à indução focal de desmielinização pelo modelo do BE na superfície ventral do tronco encefálico, mediante observação de sua movimentação e controle motor durante a travessia de uma trave elevada de madeira (beam walking test). Foi observada a ocorrência de deficiências locomotoras até 31 dias pós-injeção de BE, constatando-se ainda que a subseqüente remielinização estava relacionada com o retorno da função perdida.

[Evaluation of neurotoxic effects of lead acetate on rat radial nerve]

Lead toxicity is a common popular problem. Many researches were performed about this toxicity both in-vivo and in-vitro since 100 years ago.Those studies showed that lead have toxic effects such as behavioral disorders, decrease of IQ and decrease of learning and memory. Also lead has neurotoxic effects such as decrease of neuronal density in visual cortex of monkey, cell death in hippocampus and decrease of acetylcolin in rat's hippocampus. In this study we examin neurotoxic effects of lead on rat's radial nerve because radial nerve is a mix nerve. 24 adult male rats were divided in six groups. Groups I and II received lead acetate 4% and 2%, groups III and IV received distilled water and normal water for one month. After this time, we killed rats and exposed radial nerve from behind of arm. Then studied them with light and electron microscopy. In experimental groups we saw decrease of myelin sheath diameter and decrease of nuclear density in schwann cell. Also we saw many granules in mitochondrial matrix, active macrophage, edema and disarrangement of myelin sheath layers. We suggest that lead neurophaty is due to schwann cell injury and this lesion lead to decrease of myelin sheath

Childhood ataxia with cerebral hypomyelination (CACH) syndrome: a study of three siblings.

We report a family of three siblings with Childhood Ataxia with Cerebral Hypomyelination. All the siblings presented with early onset cerebellar ataxia beginning around five years of age with mild mental retardation. MRI showed diffuse white matter signal changes in all three patients with cerebellar atrophy while the spectroscopy was abnormal only in the eldest who was the most severely affected. The cases are reported for their rarity as well as for an opportunity of observing this uncommon disease in its stages of evolution in three siblings.

Adrenoleukodystrophy

The adenoleukodystrophy is recessive X linked hereditary affection related to the X peroxysomal origin to a deficiency in acyl-coenzyme A-synthetase. We report a case of a patient aged 9 years born after a consanguinous mariage, with no similar case in the family, who presented at the age of 8 with a cerebellar syndrome and decreasing hearing acuity. The neurological exam inationfound a cerebellar and an extrapyramidal syndrome and a deficiency of the pelvic girdle. The paraclinical investigations were in favor of myelinising affection the adrenoleukodystrophy. The patient was treated by hydrocortisone [15 mg morning, 5 mg evening]. Adrenoleukodystrophy which is a rare affection found in 1 out 400 birthis, related to the X chromosome. The gene was localised on the chromosome Xp28. It is near to factor VIII, the glucose 6 phosphate deshydrogenase, the myopathv of Emmery-dreyfus and the genes of green and red pigments. The gene was identified by Aubourg. Actually the genetic counceling is importantt in that affection, and that is thanks to the prenatal diagnosis possible by the very long chain fatty acid dosage in the chorionic villi where the culture of the amniotic cells at 9 weeks of amenorrhea permitting the diagnosis in 100% of case

Behaviour of oligodendrocytes and Schwann cells in an experimental model of toxic demyelination of the central nervous system

Oligodendrocytes and Schwann cells are engaged in myelin production, maintenance and repairing respectively in the central nervous system (CNS) and the peripheral nervous system (PNS). Whereas oligodendrocytes act only within the CNS, Schwann cells are able to invade the CNS in order to make new myelin sheaths around demyelinated axons. Both cells have some limitations in their activities, i.e. oligodendrocytes are post-mitotic cells and Schwann cells only get into the CNS in the absence of astrocytes. Ethidium bromide (EB) is a gliotoxic chemical that when injected locally within the CNS, induce demyelination. In the EB model of demyelination, glial cells are destroyed early after intoxication and Schwann cells are free to approach the naked central axons. In normal Wistar rats, regeneration of lost myelin sheaths can be achieved as early as thirteen days after intoxication; in Wistar rats immunosuppressed with cyclophosphamide the process is delayed and in rats administered cyclosporine it may be accelerated. Aiming the enlightening of those complex processes, all events concerning the myelinating cells in an experimental model are herein presented and discussed

Optic nerve sheath ectasia. case report

A 13-year-old boy with optic nerve sheath ectasia is presented. The condition is benign but can be mistaken for other more sinister conditions. The differential diagnosis of this benign lesion is given

Host parasite response in nerve in leprosy.

Nerve granulomas occur at all points across the leprosy spectrum. Studies have been made using experimental models in which mycobacteria were injected directly in the sciatic or posterior tibial nerve of the guinea pig. Clinical and electrophysiological studies demonstrated axonal damage which was confirmed by morphometric studies showing disrupted myelin sheaths and in places complete demyelination. Further immunohistological studies showed a complete disappearance of staining for certain neuropeptides. The role of Schwann cells has also been investigated. Schwann cells in nerves affected by mycobacterial granulomas, both experimental and in leprosy patients were not demonstrated to be MHC class II positive suggesting that they did not play a role in antigen presentation. Macrophages in leprosy granulomas were shown to contain TNF alpha, suggesting that this cytokine played a role in axonal damage. The role of mycobacterial heat-shock protein in nerve granulomas has not as yet been determined. The localized nature of granulomas in leprosy nerves and nerves with experimental mycobacterial granulomas has been studied by a process of excision and repair with muscle grafts. Marked recovery has been demonstrated by clinical, electrophysiological, morphometric and immuno-histochemical techniques, the latter demonstrating a return of neuropeptide production.

HTLV-1 myelopathy in Kuwait: a report of 2 patients and review of possible links

The clinical and radiological features of 2 patients with HTLV-1 myelopathy are presented. The mother of 1 patient is a carrier. This is the first report of HTLV-1 infection from Kuwait and Arabian Peninsula. Both patients were traced to Najaf, a town south of Bagdad in Iraq. Other Middle East cases were reviewed and suggest both a common source and a strong link to our cases

Valor da ressonancia magnetica na avaliacao das doencas dismielinizantes / Value of the magnetic ressonance on the evaluation of the dysmyelinating diseases

As doencas degenerativas que acometem primariamente a mielina (substancia branca) sao afeccoes variadas e raras. O diagnostico e de dificuldade variavel, algumas sao ligadas a disturbios enzimaticos do metabolismo da mielina e seu diagnostico e baseado em dosagens enzimaticas, leucocitarias ou urinarias, em outros casos nao se consegue detectar laboratorialmente a alteracao bioquimica e o diagnostico sera evocado clinicamente, particularmente nos casos em que existe megaloencefalia...