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Major histocompatibility complex class I (MHC-I) has been implicated in several types of neuroplasticity phenomena. Interferon beta-1b (IFN-β) increases MHC-I expression by motoneurons after sciatic nerve crush in mice, improving axonal growth and functional recovery. Additionally, IFN-β induces glial hypertrophy associated with upregulation of glial fibrillary acidic protein (GFAP) and MHC-I in murine astrocytes in vitro. As knowledge about MHC-I and its role in synaptic plasticity in human astrocytes (HAs) is scarce, we investigated these aspects in mature HAs obtained from the neocortex of patients undergoing surgery due to hippocampal sclerosis. Cells were exposed to media in the absence (0 IU/ml) or presence of IFN-β for 5 days (500 IU/ml). Beta-2 microglobulin (β2m), a component of the MHC-I, GFAP and vimentin proteins, was quantified by flow cytometry (FC) and increased by 100%, 60% and 46%, respectively, after IFN-β exposure. We also performed qRT-PCR gene expression analyses for β2m, GFAP, vimentin, and pro- and anti-inflammatory cytokines. Our data showed that IFN-β-treated astrocytes displayed β2m and GFAP gene upregulation. Additionally, they presented a proinflammatory profile with increase in the IL-6 and IL-1β genes and a tendency to upregulate TNF-α. Moreover, we evaluated the effect of HAs conditioned medium (CM) on the formation/maintenance of neurites/synapses by the PC12 lineage. Synaptophysin protein expression was quantified by FC. The CM of IFN-β-activated astrocytes was not harmful to PC12 neurites, and there was no change in synaptophysin protein expression. Therefore, IFN-β activated HAs by increasing GFAP, vimentin and MHC-I protein expression. Like MHC-I modulation and astrocyte activation may be protective after peripheral nerve damage and in some neurodegenerative conditions, this study opens perspectives on the pathophysiological roles of astroglial MHC-I in the human CNS.

Monobloc and facial bipartition combined with distraction osteogenesis (MFBDO) has gained popularity over the past several years as a treatment of syndromic craniosynostosis, in part because this surgical technique effectively removes many stigmatic clinical features associated with the syndromic face. The objective of this study is to detail the surgical planning used to achieve medialization of the orbits and describe the authors' experience using MFBDO to destigmatize the syndromic face. By using MFBDO, hypertelorism, vertical orbital dystopia, and downslanting of the palpebral fissure were surgically corrected in all patients, thereby destigmatizing the syndromic face.

Additive manufacturing (AM) is a technology that enables the production of models and prosthesis directly from the 3D CAD model facilitating surgical procedures, implant quality and reducing risks. Furthermore, the additive manufacturing has been used to produce implants especially designed for a particular patient, with sizes, shapes and mechanical properties optimized, in many areas of medicine such as cranioplasty surgery. This work presents AM technologies applied to design and manufacture of a biomodel, in fact, an implant for the surgical reconstruction of a large cranial defect. A series of computed tomography data was obtained and software was used to extract the cranial geometry. The protocol presented was used for creation of anatomic biomodel of the bone defect for the surgical planning as well as to design and manufacture of the patient-specific implant, reducing duration of surgery besides improving the surgical accuracy due to preoperative planning of the anatomical details.

Meningiomas and nerve sheath tumors are the most common lesions found in the intradural extramedullary compartment of the spine. Some of these lesions can be located anteriorly to the spinal cord, constituting a challenge for spine surgeons. We present a surgical technique that improves the surgical exposure of lesions located anteriorly or antero-laterally to the spinal cord. A microsurgical technique of tenting of the dentate ligament with sutures and rotation of the spinal cord is described in detail and illustrated with surgical cases. This technique increases the small microsurgical operative field and allows spinal cord retraction with the use of a natural cord component, minimizing pressure on the spinal cord delicate tissue, allowing total tumor resection. In conclusion, total resection without new neurological deficit of anterior and antero-lateral tumors can be performed using an isolated posterior approach with rotation of the spinal cord using tenting of the dentate ligament with sutures.

The use of lateral mass atlas screws is an important technique to achieve fusion and stability at the craniocervical region affected by different pathologies (degenerative, traumatic, inflammatory, neoplastic, or congenital). This paper describes the anatomy and techniques necessary for proper insertion of posterior C1 lateral mass screws, using anatomic dissection and intraoperative pictures. Knowledge of the anatomy and the surgical technique of insertion of C1 lateral mass screws are of paramount importance to have good surgical results.