A near-infrared probe for detecting and interposing amyloid beta oligomerization in early Alzheimer's disease.

BACKGROUND: The misfolding and deposition of amyloid beta (Aß) in human brain is the main hallmark of Alzheimer's disease (AD) pathology. One of the drivers of Alzheimer´s pathogenesis is the production of soluble oligomeric Aß, which could potentially serve as a biomarker of AD. METHODS: Given that the diphenylalanine (FF) at the C-terminus of Aß fragments plays a key role in inducing the AD pathology, based on the hydrophobic structure of FF, we synthesized a near-infrared BF2-dipyrrolmethane fluorescent imaging probe (NB) to detect both soluble and insoluble Aß. RESULTS: We found that NB not only binds Aß, particularly oligomeric Aß, but also interposes self-assembly of Aß through π-π interaction between NB and FF. CONCLUSION: This work holds great promise in the early detection of AD and may also provide an innovative approach to decelerate and even halt AD onset and progression.

Anterior cervical plating combined with zero-profile anchored spacer for the treatment of cervical facet dislocation in elderly patients.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of anterior cervical plating combined with zero-profile (Z-P) anchored spacer for the treatment of cervical facet dislocation in elderly patients. METHODS: This is a retrospective study. Twelve elderly patients (from 57 to 77 years old, averaged 65 years) with unilateral or bilateral facet dislocation of sub-axial cervical spine from September 2015 to September 2019 surgically treated at the authors' hospital were enrolled in this study. The patients with osteoporosis or osteopenia were all surgically treated by anterior-only procedure using cervical plating combined with zero-profile anchored spacer after closed manual reduction under general anesthesia and spinal cord monitoring. The operation times (OT), estimated blood loss (EBL), perioperative complications, were recorded. The clinical evaluation included visual analogue scales (VAS) and the American Spinal Injury Association (ASIA) scale. The radiographic evaluation included kyphotic angle (KA) and disc height (DH) and the fusion rate. RESULTS: Anterior discectomy, interbody fusion and fixation were performed in all patients after the disloctions were reduced by manual maneuver. The average OT was 66 minutes, with a range from 45 to 110 minutes. The EBL averaged 42 ml per surgical procedure, with a range from 20 to 60 ml. The VAS, ASIA, KA were improved significantly after surgery (P<0.05). The average follow-up time was 24.2 months, with a range from 12 to 38 months. There were no statistical differences between the immediately post-op KA and KA at the last follow-up (P>0.05). No disc space subsidence was observed statistically (P<0.05) Interbody fusion was obtained in all patients. Two patient experienced slight difficulty in swallowing, which were improved 6 weeks later. There were no hardware failure, no segmental instability, no wound infection or other complications. CONCLUSIONS: Manual reduction with spinal cord monitoring under general anesthesia is a safe and efficient option and the anterior cervical plating combined with Z-P spacer could achieve reliable fixation for the patients with cervical facet dislocation in the elderly patients with osteoporosis or osteopenia.

Antibiotic-loaded calcium sulfate beads in spinal surgery for patients with spondylodiscitis: a clinical retrospective study.

BACKGROUND: Various surgical techniques for treating spondylodiscitis have been proposed, but the optimal surgical treatment remains controversial. In this study, we propose a new procedure that is implanting antibiotic-loaded calcium sulfate (CS) beads into the disc after debridement using the Quadrant channel combined with percutaneous fixation through a single-stage posterolateral approach for the treatment of spondylodiscitis. Thus, the purpose of this study is to assess the safety and efficacy of this procedure. METHODS: This study collected the data of 32 patients with spine spondylodiscitis and was surgically treated in our department from July 2015 to August 2020. The Demographic data included age, gender, involved segment, and complications were collected. The intra-operative details, results of culture, functional outcome, radiologic outcome, and length of hospital stay, laboratory examination were recorded. RESULTS: The mean age of the 32 patients was 61.1 ± 9.7 years old. The mean operative time was 135.0 ± 30.6 minutes, and the mean blood loss was 243.4 ± 92.1 ml. The positive rate of culture was 72%. The mean Visual analogue scale (VAS) and Oswestry Disability Index (ODI) score significantly improved from 7.5 to 1.6 and from 65% to 10%. Cobb angle was significantly improved and could be maintained at final follow-up. New bone formation was observed in all patients. There were no recurrences of infection in our study. CONCLUSIONS: The posterolateral debridement and percutaneous fixation combined with antibiotic-loaded calcium sulfate beads filling are effective in the treatment of spondylodiscitis in terms of infection control, early mobilization, and recovery.

Microscopic extra-laminar sequestrectomy (MELS) for the treatment of hidden zone lumbar disc herniation: report of the surgical technique, patient selection, and clinical outcomes.

BACKGROUND: The area which located at the medial pedicle, posterior vertebral body and ventral hemilamina is defined as the hidden zone. Surgical management of hidden zone lumbar disc herniation (HZLDH) is technically challenging due to its difficult surgical exposure. The conventional interlaminar approach harbors the potential risk of post-surgical instability, while other approaches consist of complicated procedures with a steep learning curve and prolonged operation time. OBJECTIVE: To introduce microscopic extra-laminar sequestrectomy (MELS) technique for treatment of hidden zone lumbar disc herniation and present clinical outcomes. METHODS: Between Jan 2016 to Jan 2018, twenty one patients (13 males) with HZLDH were enrolled in this study. All patients underwent MELS (19 patients underwent sequestrectomy only, 2 patients underwent an additional inferior discectomy). The nerve root and fragment were visually exposed using MELS. The operation duration, blood loss, intra- and postoperative complications, and recurrences were recorded. The Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and the modified MacNab criteria were used to evaluate clinical outcomes. Postoperative stability was evaluated both radiologically and clinically. RESULTS: The mean follow-up period was 20.95 ± 2.09 (18-24) months. The mean operation time was 32.43 ± 7.19 min and the mean blood loss was 25.52 ± 5.37 ml. All patients showed complete neurological symptom relief after surgery. The VAS and ODI score were significantly improved at the final follow-up compared to those before operation (7.88 ± 0.70 vs 0.10 ± 0.30, 59.24 ± 10.83 vs 11.29 ± 3.59, respectively, p < 0.05). Seventeen patients (81%) obtained an "excellent" outcome and the remaining four (19%) patients obtained a "good" outcome based the MacNab criteria. One patient suffered reherniation at the same level one year after the initial surgery and underwent a transforaminal endoscopic discectomy. No major complications and postoperative instability were observed. CONCLUSIONS: Our observation suggest that MELS is safe and effective in the management of HZLDH. Due to its relative simplicity, it comprises a flat surgical learning curve and shorter operation duration, and overall results in reduced disturbance to lumbar stability.

Minimally invasive far lateral debridement combined with posterior instrumentation for thoracic and lumbar tuberculosis without severe kyphosis.

BACKGROUND: Anti-tuberculous therapy (ATT) alone cannot easily cure spine tuberculosis (STB) though it is the most essential treatment. Many studies have confirmed the efficacy of the surgical treatment of STB through anterior, anterolateral, posterior debridement, and intervertebral fusion or combined with internal fixation. However, the conventional surgical approach requires extensive exposure of the affected areas with high rates of morbidity and mortality. Recently, minimally invasive surgery has come into use to reduce iatrogenic trauma and relevant complications. Here, we introduced a novel technique for the treatment of thoracic and lumbar spine tuberculosis: minimally invasive far lateral debridement and posterior instrumentation (MI-FLDPI). In this study, we evaluated the technical feasibility, the clinical outcomes, and the postoperative complications. METHODS: We did a prospective, non-randomized study on this new technique. Twenty three patients (13 males) with thoracic or lumbar spine tuberculosis who underwent minimally invasive far lateral debridement and posterior instrumentation were included in the study. The preoperative comorbidities, operation duration, intra-operative hemorrhage, Cobb's angles, and postoperative complications were recorded and analyzed. Clinical outcomes were evaluated by Visual Analog Scale (VAS), Oswestry Disability Index (ODI), neurological recovery, and eradication of tuberculosis. Radiological outcomes were evaluated by changes in Cobb's angle and fusion status of the affected segments. RESULTS: The patients were followed for an average of 19 months (ranging from 12 to 36 months). At the final follow-up, CRP and ESR of all patients were normal. The VAS and ODI were significantly improved compared with preoperative values (P < 0.05). No evident progression of the kyphotic deformity was found after surgery. Twenty two patients showed spontaneous peripheral interbody fusion 1 year after surgery. There were no failure of the instrumentation even though a young female with drug-resistant tuberculosis showed no sign of interbody fusion at the third year follow-up. All the patients with preoperative neurological deficit showed complete recovery at the final follow-up. CONCLUSIONS: MI-FLDPI using expandable tubular retractor could be recommended to treat thoracic and lumbar spine tuberculosis for the advantages of less trauma, earlier recovery, and less complications. Spontaneous peripheral interbody fusion was observed in nearly all the cases even without bone grafting.

Inferior alveolar and mental nerve injuries associated with open reduction and internal fixation of mandibular fractures: a Seven Year retrospective study.

PURPOSE: To document adverse neurosensory changes in the inferior alveolar nerve (IAN) and mental nerve (MN) after surgical mandibular fracture treatment and to identify risk factors associated with these changes. MATERIALS AND METHODS: A retrospective study of patients surgically treated for mandibular fractures. The primary study variable was the postoperative change in IAN/MN neurosensory examination after fracture fixation. Risk factors were categorized as demographic, anatomic, experience of the operator, fracture displacement and number of miniplates placed at each fracture site. Appropriate statistics were computed. RESULTS: 209 patients with 293 fractures were analysed. One hundred twenty fractures (41%) were located between the lingula and mental foramen, and 173 fractures (59%) were located distal to the mental foramen. Two hundred seventeen (41%) were displaced by 5 mm or more. In 38 fractures (13%), the IAN/MN neurosensory status worsened after treatment. In a multivariate model, fracture displacement, operator inexperience and two plate fixation were associated with a statistically significant risk (P ≤ 0.05) for postoperative deterioration of IAN/MN sensation. CONCLUSION: Fixation with two miniplates, fracture displacement of 5 mm or more and operator inexperience were associated with an increased risk for deterioration of the IAN/MN neurosensory status after treatment of mandibular fractures.