Monogenic, Polygenic, and MicroRNA Markers for Ischemic Stroke.

Ischemic stroke (IS) is a leading disease with high mortality and disability, as well as with limited therapeutic window. Biomarkers for earlier diagnosis of IS have long been pursued. Family and twin studies confirm that genetic variations play an important role in IS pathogenesis. Besides DNA mutations found previously by genetic linkage analysis for monogenic IS (Mendelian inheritance), recent studies using genome-wide associated study (GWAS) and microRNA expression profiling have resulted in a large number of DNA and microRNA biomarkers in polygenic IS (sporadic IS), especially in different IS subtypes and imaging phenotypes. The present review summarizes genetic markers discovered by clinical studies and discusses their pathogenic molecular mechanisms involved in developmental or regenerative anomalies of blood vessel walls, neuronal apoptosis, excitotoxic death, inflammation, neurogenesis, and angiogenesis. The possible impact of environment on genetics is addressed as well. We also include a perspective on further studies and clinical application of these IS biomarkers.

Metastasis development at the site of cervical spine arthrodesis.

Biologically, the site of arthrodesis provides a microenvironment replete of growth factors and active remodeling, which is propitious for bone regrowth. There is a theoretical possibility though that this microenvironment would also provide a fertile site for metastatic deposits to occur. Although spinal fusion with various types of instrumentation is commonly used to treat various disorders, development of tumors at the site of spinal arthrodesis has not been previously reported. We present the clinical, radiographic, and pathological features of a case of previously undiagnosed metastatic adenocarcinoma, occurring 1 year following anterior arthrodesis and fusion for cervical spondylotic myelopathy at the C3-C4 level. The patient's initial radiologic presentation suggested an epidural abscess with osteomyelitic destruction of C3 and C4. Our report alerts surgeons to the possibility that metastasis may occur at the site of a previous spinal arthrodesis.