Superficial siderosis of the central nervous system caused by myxopapillary ependymoma of conus medullaris and cauda equine: a case report and literature review / 北京大学学报(医学版)

Superficial siderosis of the central nervous system (SSCNS) is a rare disorder caused by hemosiderin deposits in the subpial layers of the brain and spinal cord due to prolonged or recurrent low-grade bleeding into the cerebrospinal fluid (CSF). Central nervous system tumor could be one of the sources of bleeding. Some problems exist at present regarding the diagnosis and treatment of SSCNS in China. On account of fewer cases, the insufficient awareness of the condition, and the lack of long-term follow-up data, enough attention has not been paid to etiological diagnosis. The speculative high rate of missed diagnoses of SSCNS indicates a great disparity in the treatment from the world's advanced level. Related data of clinical and basic research need to accumulate as soon as possible to promote the clinical diagnosis and treatment of the disease. The progressive neurological deficits are involved in the typical clinical manifestations of SSCNS with a triad of bilateral symmetrical sensorineural hearing loss, cerebellar ataxia and signs of corticospinal tract dysfunction. Nevertheless, there are few patients with the triad signs at the same time, which lead to a delayed diagnosis or misdiagnosis. Detection of this disease was commonly post-mortem until the advent of MRI with signal and location characteristics, which made diagnosis easier. Siderosis appears as a hypointense rim covering the surface of the cerebellum, the brain stem, the spinal cord, similar to a black pencil line, thin on SE-T2-weighted images, thick and conspicuous on GE-T2-weighted images or on susceptibility-weighted imaging (SWI). The only effective way of treating the disorder is to identify the source of bleeding and remove it. MR examination is useful for seeking a source of bleeding too. Therefore, once superficial siderosis is considered, lesions of the central nervous system must be searched using MRI of the brain and spine. We report here a 37-year-old male diagnosed of SSCNS with the classical clinical symptoms of cerebellar ataxia, sensorineural hearing loss and myelopathy. T2-weighed MRI showed characteristic marginal hypo-intensity around the central nervous system. Etiological explorations revealed a large conus medullaris / cauda equina ependymoma filling the lumbosacral spinal canal, a myxopapillary ependymoma (MPE) confirmed by surgical resection and histopathological examination. The related literature was reviewed to ascertain the mechanism of SSCNS secondary to MPE, and to discuss the pathogenesis, clinical features, diagnosis and treatment of SSCNS. This paper aims to improve the awareness of SSCNS and diagnostic level, and to lay stress on the etiological explorations that is beneficial to the development of exact treatment plan.

Cloning identification and functional analysis of human IL-17A promoter

OBJECTIVE@#To conduct the cloning identification and characterization of the sequence of human IL-17A promoter so as to analyze the regulatory mechanism of the gene expression of IL-17.@*METHODS@#First of all, the potential promoter region of IL-17A was found by means of the bioinformatics methods. Then, it was cloned into the reporter vector with PCR technique. Finally, the activity of the test promoter was determined by dual luciferase reporter system.@*RESULTS@#Two transcriptional start points of the upper region, 600 bp and 1000 bp, of IL-17A were obtained by PCR clone and proved to have certain activities by dual luciferase reporter system. Also, they could be activated by IL-17A activator STAT3, which could start the expression of the reported gene.@*CONCLUSIONS@#Clone established the regulatory region of human IL-17A promoter, which provided bases to the subsequent function research.

Cloning identification and functional analysis of human IL-17A promoter

Objective To conduct the cloning identification and characterization of the sequence of human IL-17A promoter so as to analyze the regulatory mechanism of the gene expression of IL-17. Methods First of all, the potential promoter region of IL-17A was found by means of the bioinformatics methods. Then, it was cloned into the reporter vector with PCR technique. Finally, the activity of the test promoter was determined by dual luciferase reporter system. Results Two transcriptional start points of the upper region, 600 bp and 1000 bp, of IL-17A were obtained by PCR clone and proved to have certain activities by dual luciferase reporter system. Also, they could be activated by IL-17A activator STAT3, which could start the expression of the reported gene. Conclusions Clone established the regulatory region of human IL-17A promoter, which provided bases to the subsequent function research.