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Background: There are many reports about the risk factors for recurrence after laminectomy surgery. Some surgeons use unilateral and bilateral fusion to provide sufficient stability to the lumbar spine. However, its strength, safety, and effectiveness in young patients are not widely known. Therefore, this study was conducted to compare surgical methods of laminectomy with unilateral and bilateral fixation and laminectomy alone without interbody fusion in young patients with lumbar spinal stenosis. Methods: 90 patients eligible for lumbar spinal stenosis surgery were selected through convenience sampling and randomly divided into three groups: laminectomy without fixation (A), laminectomy with unilateral fixation (B), and bilateral fixation (C). Pain, functional disability, quality of life, recurrent disc, adjacent segment disease (ASD), and fusion rate were evaluated and compared among the three groups six months post-surgery. The data were analyzed using SPSS version 16. Results: Six months after surgery, the mean score of functional disability in the bilateral group was significantly higher than the other groups (12.92 (3.30) vs 5.52 (1.91) and 4.30 (1.84), P < 0.05). Also, the highest mean score of pain after surgery was observed in the bilateral group (4.33 (0.70) vs 1.81(0.68) and 1.63(0.56), P < 0.05). The mean score of quality of life in the unilateral group was significantly higher than the other groups (87.81 (5.67) vs 68.58 (3.08) and 56.07 (4.04), P < 0.05). No significant difference was observed between the groups (P > 0.05) regarding fusion, recurrent disc herniation, and adjacent segment disease. Conclusions: Unilateral fixation provides the same benefits as bilateral fixation but has the additional benefits of being less invasive and minimizing the disadvantages of other investigated techniques during and after surgery.
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Purpose: This study presents a rare case of avulsion fracture of the anterior inferior iliac spine, typically occurring in adolescents engaged in physical activities. The purpose of this study is to emphasize the diagnostic challenges and conservative treatment options available for this condition. Method: We describe the case of a 14-year-old healthy adolescent who suffered from an avulsion fracture following pelvic trauma after participating in a short-distance sprint. Initial physical examination and X-ray imaging were inconclusive, showing no apparent fractures. Due to parental refusal of a Computerized Tomography (CT) scan by concerns over the potential risks associated with radiation exposure, a diagnostic ultrasound was performed, which confirmed the presence of an avulsion fracture at the anterior inferior iliac spine. Results: The ultrasound findings led to a conservative treatment approach, involving rest, and unloading of the affected limb. Follow-up assessments indicated significant pain relief within four weeks and enabled the resumption of partial physical activity after six months. Conclusion: This case highlights the utility of ultrasound as an effective alternative diagnostic tool in situations where CT scans are not permissible. Additionally, it demonstrates that conservative management can be successful in treating avulsion fractures of the anterior inferior iliac spine in adolescents, leading to satisfactory recovery and return to activity.
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White cord syndrome is an extremely rare type of cervical spinal cord ischemia characterized by sudden neurological deterioration following surgical spinal decompression. The underlying cause is believed to be immediate relief from chronic compression on the spinal cord, triggering an inflammatory response known as ischemic reperfusion injury. A 49-year-old male presented in the office with neck pain and chronic symptoms of progressive cervical myelopathy: clumsiness, gait instability, and dropping things. An MRI of the cervical spine demonstrated severe central canal stenosis with spinal cord compression and myelomalacia at the C3-C4 level. The patient underwent a planned anterior cervical discectomy and fusion procedure from C3 to C5. Following the surgery, he developed monoplegia in his left lower extremity. His postoperative MRI revealed white cord syndrome, characterized by an increase in the signal change of the spinal cord. This finding was consistent with an ischemic reperfusion injury to the spinal cord post-decompression. White cord syndrome is thought to be caused by a reperfusion injury following surgical decompression of a previously compressed segment of the spinal cord, characterized by the rapid return of blood flow. This involves oxidative damage caused by free oxygen radicals and inflammatory molecules, such as reactive oxygen species, which lead to lipid peroxidation of neuronal membranes. Surgeons should be aware of this rare complication and warn patients preoperatively.
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STUDY DESIGN: Retrospective cohort study. OBJECTIVES: Surgical infections are unfortunately a fairly common occurrence in spine surgery, with rates reported as high as 16â¯%. However, there is a relative paucity of studies that look to understand how surgical infections may impact outcome variables. The aim of this study was to assess the impact of surgical infection on other perioperative complications, extended hospital length of stay (LOS), discharge disposition, and unplanned readmission following spine surgery. METHODS: A retrospective cohort study was performed using the 2016-2022 ACS NSQIP database. Adults receiving spine surgery for trauma, degenerative disease, and tumors were identified using CPT and ICD-9/10 codes. Patients were divided into two cohorts: surgical infection (superficial surgical site infection, deep surgical site infection, organ space surgical site infection, or wound dehiscence) and no surgical infection (those who did not experience any infection). Patient demographics, comorbidities, intraoperative variables, postoperative adverse events (AEs), and healthcare resource utilization were assessed. Multivariate logistic regression analysis was utilized to identify predictors of AEs, extended hospital length of stay, non-routine discharge, and unplanned readmission. RESULTS: In our cohort of 410,930 patients, 7854 (2.2â¯%) were found to have experienced a surgical infection. Regarding preoperative variables, a greater proportion of the surgical infection cohort was a female (p < 0.001) and had a higher mean BMI (p < 0.001), greater frailty and ASA scores (p < 0.001), and higher rates of all presenting comorbidities included in the study. Rates of AEs (p < 0.001), unplanned readmission (p < 0.001), reoperation (p < 0.001), non-home discharge (p < 0.001), and 30-day mortality were all greater in the surgical infection group when compared to the group without surgical infection. On multivariate analysis, surgical infection was found to be an independent predictor of experiencing postoperative complications [aOR: 6.15, 95â¯% CI: (5.72, 6.60), p < 0.001], prolonged LOS [2.71, 95â¯% CI: (2.54, 2.89), p < 0.001], non-routine discharge [aOR: 1.74, 95â¯% CI: (1.61, 1.88), p < 0.001], and unplanned readmission [aOR: 22.57, 95â¯% CI: (21.06, 24.19), p < 0.001]. CONCLUSIONS: Our study found that surgical infection increases the risk of complications, extended LOS, non-routine discharge, and unplanned readmission. Such findings warrant further studies that aim to validate these results and identify risk factors for surgical infections.
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BACKGROUND: The accurate and safe positioning of cervical pedicle screws is crucial. While augmented reality (AR) use in spine surgery has previously demonstrated clinical utility in the thoracolumbar spine, its technical feasibility in the cervical spine remains less explored. PURPOSE: The objective of this study was to assess the precision and safety of AR-assisted pedicle screw placement in the cervical spine. STUDY DESIGN: In this experimental study, five cadaveric cervical spine models were instrumented from C3 to C7 by five different spine surgeons. The navigation accuracy and clinical screw accuracy were evaluated. METHODS: Post-procedural CT scans were evaluated for clinical accuracy by two independent neuroradiologists using the Gertzbein-Robbins scale. Technical precision was assessed by calculating the angular trajectory (°) and linear screw tip (mm) deviations in the axial and sagittal planes from the virtual pedicle screw position as recorded by the AR-guided platform during the procedure compared to the actual pedicle screw position derived from post-procedural imaging. RESULTS: A total of forty-one pedicle screws were placed in five cervical cadavers, with each of the five surgeons navigating at least seven screws. Gertzbein-Robbins grade of A or B was achieved in 100% of cases. The mean values for tip and trajectory errors in the axial and sagittal planes between the virtual versus actual position of the screws was less than 3 mm and 30°, respectively (p<0.05). None of the cervical screws violated the cortex by more than 2 mm or displaced neurovascular structures. CONCLUSIONS: AR-assisted cervical pedicle screw placement in cadavers demonstrated clinical accuracy comparable to existing literature values for image-guided navigation methods for the cervical spine. CLINICAL SIGNIFICANCE: This study provides technical and clinical accuracy data that supports clinical trialing of AR-assisted subaxial cervical pedicle screw placement.
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Spine pain (SP) is the most common musculoskeletal disorder that causes transitional forms of motor disability. Considering its affordability and safety, manipulative therapy (MT) stands as one of the primary therapeutic approaches for SP and the related dysfunctional consequences. However, it is still difficult to assess and quantify the results of this treatment since there is a lack of objective evaluation tools in the available scientific literature. Thus, the purpose of this comprehensive review is to summarize the main outcomes used to evaluate the effectiveness of spine manipulations, focusing on their strengths and weaknesses. An extensive review of the PubMed, Cochrane, and Embase databases was performed to identify the literature of the last ten years regarding MT and the related assessment tools. A total of 12 studies met the inclusion criteria. The analyzed literature indicates that a wide range of outcome measures have been used to assess the effectiveness of spine MT. Pain is the main aspect to be investigated but it remains difficult to elucidate since it is strongly linked to various dimensions such as self-perception and psychological aspects. Therefore, it seems necessary to include new tools for evaluating the effects of spine MT, with the aim of exploiting new technologies and taking into consideration the SP biomechanical and biopsychosocial aspects.
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Calcium phosphate (CaP)-based materials are largely explored in orthopedics, to increase osseointegration of the prostheses and specifically in spine surgery, to permit better fusion. To address these aims, nanostructured biogenic apatite coatings are emerging, since they better mimic the characteristics of the host tissue, thus potentially being better candidates compared to their synthetic counterpart. Here, we compare hydroxyapatite (HA) nanostructured coatings, obtained by ionized jet deposition, starting from synthetic and natural sources. The starting materials and the corresponding films are characterized and compared from a compositional and morphological point of view, then their stability is studied after post-treatment annealing. Although all the films are formed by globular aggregates and show morphological features at different scales (from nano to micro), significant differences are found in composition between the synthetic and naturally derived HA in terms of magnesium and sodium content, carbonate substitution and Ca/P ratio, while differences between the coatings obtained by the different natural HA sources are minor. In addition, the shape of the aggregates is also target-dependent. All coatings have a good stability after over 14 days of immersion in medium, with natural apatite coatings showing a better behavior, as no cracking and detachments are observed during immersion. Based on these results, both synthetic and naturally derived apatitic materials appear promising for applications in spine surgery, with coatings from natural sources possessing physiochemical properties more similar to the mineral phase of the human bone tissue.
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Soccer teams integrate specific exercises into their typical workout programs for injury prevention. This study examined the effects of hamstring exercise on paraspinal and hamstring stiffness. These findings can inform training and rehabilitation programs to improve muscle health and prevent injuries. Fifteen young, healthy males performed passive and active (submaximal) knee flexion efforts from 0°, 45°, to 90° angle of knee flexion from the prone position. Using shear-wave elastography (SWE) and surface electromyography, we measured the elastic modulus and root mean square (RMS) signal of the erector spinae (ES), multifidus (MF), semitendinosus (ST), and semimembranosus (SM) during different knee flexion angles. Passive SWE modulus at 0° was 12.44 ± 4.45 kPa (ES), 13.35 ± 6.12 kPa (MF), 22.01 ± 4.68 kPa (ST), and 21.57 ± 5.22 kPa (SM) and it was greater (p < 0.05) compared to 45° and 90°. The corresponding values during knee flexion contractions at 0° increased to 18.99 ± 6.11 kPa (ES), 20.65 ± 11.31 kPa (MF), 71.21 ± 13.88 kPa (ST), and 70.20 ± 14.29 kPa (SM) and did not differ between angles (p > 0.05). Compared to rest, the relative increase in the SWE modulus during active contraction had a median value (interquartile range) ranging from 68.11 (86.29) to 101.69 (54.33)% for the paraspinal muscles and it was moderately to strongly correlated (r > 0.672) with the corresponding increase of the hamstring muscles [ranging from 225.94 (114.72) to 463.16 (185.16)%]. The RMS signal was greater during active compared to passive conditions, and it was lower at 90° compared to 45° (for SM/ST) and 0° (for all muscles). The association between paraspinal and hamstring passive muscle stiffness indicates a potential transmission of forces through myofascial connections between the lumbar spine and the lower limbs. In this laboratory setting, hamstring exercises affected the stiffness of the paraspinal muscles.
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INTRODUCTION: There is a lack of information on return to sport and patient-reported outcome measures (PROMs) in amateur athletes after isolated spine injuries. METHODS: A single-center cohort study in amateur athletes aged 18 to 60 with isolated spine injuries; clinical data collection and follow-up via telephone interview and standardized PROMs (Short-Form 36, Oswestry and Neck Disability Index, Tampa Scale of Kinesiophobia, Hospital Anxiety and Depression Scale, Pain Visual Analog Scale). Bivariate analyses of potential influencing factors on PROMs were conducted using the Wilcoxon Signed-Rank Test. p-values < 0.05 were considered statistically significant. RESULTS: Out of the 80 included participants, 78% (n = 62) were active in sport at follow-up. PROMs were slightly worse than those described for the age-adjusted general population. There were consistent associations of better PROMs with having reached the subjective preinjury level of performance in sport, while injury severity and surgical or conservative therapy did not show consistent associations with PROMs. CONCLUSION: Most amateur athletes resume their sports activity after a spine injury. Better outcomes are associated with individuals' resumption of sport and subjective level of performance, while injury severity and surgical or conservative therapy do not show consistent associations with PROMs, highlighting the importance of patient education, rehabilitation, and encouragement.
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BACKGROUND: We evaluated the role of dual-energy computed tomography (DECT)-based collagen maps in assessing thoracic disc degeneration. METHODS: We performed a retrospective analysis of patients who underwent DECT and magnetic resonance imaging (MRI) of the thoracic spine within a 2-week period from July 2019 to October 2022. Thoracic disc degeneration was classified by three blinded radiologists into three Pfirrmann categories: no/mild (grade 1-2), moderate (grade 3-4), and severe (grade 5). The DECT performance was determined using MRI as a reference standard. Interreader reliability was assessed using intraclass correlation coefficient (ICC). Five-point Likert scales were used to assess diagnostic confidence and image quality. RESULTS: In total, 612 intervertebral discs across 51 patients aged 68 ± 16 years (mean ± standard deviation), 28 males and 23 females, were assessed. MRI revealed 135 no/mildly degenerated discs (22.1%), 470 moderately degenerated discs (76.8%), and 7 severely degenerated discs (1.1%). DECT collagen maps achieved an overall accuracy of 1,483/1,838 (80.8%) for thoracic disc degeneration. Overall recall (sensitivity) was 331/405 (81.7%) for detecting no/mild degeneration, 1,134/1,410 (80.4%) for moderate degeneration, and 18/21 (85.7%) for severe degeneration. Interrater agreement was good (ICC = 0.89). Assessment of DECT-based collagen maps demonstrated high diagnostic confidence (median 4; interquartile range 3-4) and good image quality (median 4; interquartile range 4-4). CONCLUSION: DECT showed an overall 81% accuracy for disc degeneration by visualizing differences in the collagen content of thoracic discs. RELEVANCE STATEMENT: Utilizing DECT-based collagen maps to distinguish various stages of thoracic disc degeneration could be clinically relevant for early detection of disc-related conditions. This approach may be particularly beneficial when MRI is contraindicated. KEY POINTS: A total of 612 intervertebral discs across 51 patients were retrospectively assessed with DECT, using MRI as a reference standard. DECT-based collagen maps allowed thoracic disc degeneration assessment achieving an overall 81% accuracy with good interrater agreement (ICC = 0.89). DECT-based collagen maps could be a good alternative in the case of contraindications to MRI.
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Colágeno , Degeneração do Disco Intervertebral , Imageamento por Ressonância Magnética , Vértebras Torácicas , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Degeneração do Disco Intervertebral/diagnóstico por imagem , Idoso , Estudos Retrospectivos , Vértebras Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Minimally invasive surgical techniques for sacroiliac joint (SIJ) fixation have the potential to reduce risk and improve patient outcomes, but evidence remains limited. This interim analysis presents initial findings from an ongoing prospective study evaluating the safety and efficacy of the Catamaran System. METHODS: The primary endpoint of success at 6 months was defined as a ≥20 mm improvement in SIJ pain (Visual Analog Scale, VAS), no neurologic worsening, absence of device-related serious adverse events (SAEs), and no surgical reintervention. Secondary endpoints included 6 month evaluation of the Oswestry Disability Index (ODI), patient satisfaction, and 12 month radiographic CT fusion, performed by an indpendent radiologist. RESULTS: Thirty-three consecutive patients (mean age: 58.9 years; %-females: 76%; Body Mass Index: 30.5) were treated across six U.S. clinical sites. At the primary endpoint of 6 months, 80% of patients met the criteria for success, with no device-related SAEs and no surgical reintervention reported. VASSIJ-Pain significantly decreased from preoperative levels (mean: 80.9 mm) to 6 months postoperatively (31.1 mm; p < 0.001). Mean ODI scores also showed a significant improvement from preoperative values (51.9%) to 6 months postoperatively (29.6%, p < 0.01). Patients reported high satisfaction rates throughout all follow-ups, with 93.3% of patients being satisfied at 6 months. CONCLUSION: In patients diagnosed with chronic SIJ pain, minimally invasive inferior-posterior delivery of the Catamaran implant was safe and effective in relieving pain and reducing disability.
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Biological and artificial neural networks learn by modifying synaptic weights, but it is unclear how these systems retain previous knowledge and also acquire new information. Here, we show that cortical pyramidal neurons can solve this plasticity-versus-stability dilemma by differentially regulating synaptic plasticity at distinct dendritic compartments. Oblique dendrites of adult mouse layer 5 cortical pyramidal neurons selectively receive monosynaptic thalamic input, integrate linearly, and lack burst-timing synaptic potentiation. In contrast, basal dendrites, which do not receive thalamic input, exhibit conventional NMDA receptor (NMDAR)-mediated supralinear integration and synaptic potentiation. Congruently, spiny synapses on oblique branches show decreased structural plasticity in vivo. The selective decline in NMDAR activity and expression at synapses on oblique dendrites is controlled by a critical period of visual experience. Our results demonstrate a biological mechanism for how single neurons can safeguard a set of inputs from ongoing plasticity by altering synaptic properties at distinct dendritic domains.
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Dendritos , Plasticidade Neuronal , Células Piramidais , Receptores de N-Metil-D-Aspartato , Sinapses , Animais , Dendritos/metabolismo , Dendritos/fisiologia , Sinapses/metabolismo , Sinapses/fisiologia , Camundongos , Receptores de N-Metil-D-Aspartato/metabolismo , Plasticidade Neuronal/fisiologia , Células Piramidais/metabolismo , Células Piramidais/fisiologia , Camundongos Endogâmicos C57BL , MasculinoRESUMO
Spanning two decades since the 1st generation spinal robotics inception, the robot-assisted spine surgery (RSS) technology has evolved through generations, culminating in the 4th generation characterized by real-time visual navigation and wire-free screw placement. The fundamental principles of RSS technology include surgical planning, tracking, image registration, and robotic arm control technologies. Currently, RSS technology is maturely employed in thoracolumbar procedures and is progressively being applied in cervical surgeries, spinal tumor resections, and percutaneous operations, offering advantages in reducing tissue trauma and exposure to radiation, thereby improving patient outcomes. Emerging research also focuses on the cost-effectiveness of clinical applications and robot-specific complications. With the integration of artificial intelligence into surgical planning, RSS technology is poised to further incorporate emerging technologies and expand its application across a broader clinical spectrum.
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Procedimentos Cirúrgicos Robóticos , Fusão Vertebral , Humanos , Inteligência Artificial , Vértebras Cervicais/cirurgia , História do Século XX , História do Século XXI , Vértebras Lombares/cirurgia , Procedimentos Cirúrgicos Robóticos/história , Procedimentos Cirúrgicos Robóticos/instrumentação , Procedimentos Cirúrgicos Robóticos/métodos , Procedimentos Cirúrgicos Robóticos/tendências , Doenças da Coluna Vertebral/cirurgia , Fusão Vertebral/história , Fusão Vertebral/instrumentação , Fusão Vertebral/métodos , Fusão Vertebral/tendências , Neoplasias da Coluna Vertebral/cirurgia , Coluna Vertebral/cirurgia , Vértebras Torácicas/cirurgiaRESUMO
BACKGROUND: Perioperative blood glucose control has been demonstrated to influence outcomes following spine surgery, though this association has not been fully elucidated in patients with traumatic spine injuries. This study sought to determine the association between perioperative blood glucose levels and complications or outcomes in patients undergoing spine surgery due to injury. METHODS: A retrospective review was conducted to identify patients who underwent spine surgery due to traumatic injuries between 1 March 2020 and 29 September 2022 at a single academic institution. Descriptive factors, complications, and outcomes were compared between those with a postoperative blood glucose level of <200 mg/dL and those with a preoperative glucose of <200 mg/dL. RESULTS: Patients with a post- and preoperative blood glucose of ≥200 mg/dL had significantly higher odds of respiratory complications (OR = 2.1, 2.1, P = 0.02, 0.03), skin/wound complications (OR = 2.2, 2.8, P = 0.04, 0.03), and increased hospital length of stay (OR = 9.6, 12.1, P = 0.02, 0.03) compared with those with blood glucose of <200 mg/dL. Those with postoperative glucose ≥200 mg/dL also had significantly higher odds of inpatient mortality (OR = 4.5, P = 0.04) when controlling for confounding factors. Neither pre- nor postoperative blood glucose of ≥200 mg/dL was associated with an improvement in American Spinal Injury Association Impairment Scale score at the final follow-up when controlling for multiple confounding factors (P = 0.44, 0.06). CONCLUSION: Elevated blood glucose both pre- and postoperatively was associated with an increased rate of postoperative complications and negative postoperative outcomes. However, there was no association between elevated blood glucose levels and neurological recovery following traumatic spinal injury.
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Dendrite morphology and dendritic spines are key features of the neuronal networks in the brain. Abnormalities in these features have been observed in patients with psychiatric disorders and mouse models of these diseases. In utero electroporation is an easy and efficient gene transfer system for developing mouse embryos in the uterus. By combining with the Cre-loxP system, the morphology of individual neurons can be clearly and sparsely visualized. Here, we describe how this labeling system can be applied to visualize and evaluate the dendrites and dendritic spines of cortical neurons.
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Espinhas Dendríticas , Eletroporação , Neuritos , Animais , Eletroporação/métodos , Camundongos , Feminino , Neuritos/metabolismo , Espinhas Dendríticas/metabolismo , Gravidez , Útero/citologia , Técnicas de Transferência de Genes , Neurônios/citologia , Neurônios/metabolismoRESUMO
During the development of mammalian brains, pyramidal neurons in the cerebral cortex form highly organized six layers with different functions. These neurons undergo developmental processes such as axon extension, dendrite outgrowth, and synapse formation. A proper integration of the neuronal connectivity through dynamic changes of dendritic branches and spines is required for learning and memory. Disruption of these crucial developmental processes is associated with many neurodevelopmental and neurodegenerative disorders. To investigate the complex dendritic architecture, several useful staining tools and genetic methods to label neurons have been well established. Monitoring the dynamics of dendritic spine in a single neuron is still a challenging task. Here, we provide a methodology that combines in vivo two-photon brain imaging and in utero electroporation, which sparsely labels cortical neurons with fluorescent proteins. This protocol may help elucidate the dynamics of microstructure and neural complexity in living rodents under normal and disease conditions.
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Neurônios , Animais , Camundongos , Neurônios/citologia , Neurônios/metabolismo , Eletroporação/métodos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/ultraestrutura , Células Piramidais/metabolismo , Células Piramidais/citologia , Feminino , Córtex Cerebral/citologia , Dendritos/metabolismoRESUMO
The molecular mechanisms underlying neurite formation include multiple crosstalk between pathways such as membrane trafficking, intracellular signaling, and actin cytoskeletal rearrangement. To study the proteins involved in such complex pathways, we present a detailed workflow of the sample preparation for mass spectrometry-based proteomics and data analysis. We have also included steps to perform label-free quantification of proteins that will help researchers quantify changes in the expression levels of key regulators of neuronal morphogenesis on a global scale.
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Neuritos , Proteômica , Proteômica/métodos , Neuritos/metabolismo , Animais , Humanos , Espectrometria de Massas/métodos , Proteoma/metabolismo , Proteoma/análise , Cromatografia Líquida/métodosRESUMO
Plasticity of synaptic transmission underlies learning and memory. It is accompanied by changes in the density and size of synapses, collectively called structural plasticity. Therefore, understanding the mechanism of structural plasticity is critical for understanding the mechanism of synaptic plasticity. In this chapter, we describe the procedures and equipment required to image structural plasticity of a single dendritic spine, which hosts excitatory synapses in the central nervous system, and underlying molecular interactions/biochemical reactions using two-photon fluorescence lifetime microscopy (2P-FLIM) in combination with Förster resonance energy transfer (FRET)-based biosensors.
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Espinhas Dendríticas , Transferência Ressonante de Energia de Fluorescência , Microscopia de Fluorescência por Excitação Multifotônica , Plasticidade Neuronal , Espinhas Dendríticas/metabolismo , Espinhas Dendríticas/ultraestrutura , Espinhas Dendríticas/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Transferência Ressonante de Energia de Fluorescência/métodos , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Sinapses/metabolismo , Sinapses/fisiologia , Camundongos , Técnicas Biossensoriais/métodosRESUMO
Background: Accidental injuries sustained during helocasting remain unexamined. Methods: Conditions prevalent during a helocasting exercise performed at a still water body and the resulting casualties were analyzed. Results: Despatch from greater-than-ideal height (>7 m) and speed (>5 knots) causes a high-velocity impact of the body with water in a non-aerodynamic configuration, exposing maximal body area at penetration. The brunt is borne by the torso/back, specifically, the lungs, ribs, and posterior aspect of the spine. The injuries result from direct trauma, sudden deceleration, barotrauma, and hyperflexion. Computerized tomography (CT) is the imaging of choice in the assessment of these injuries. Prompt evacuation to an equipped center, whilst stabilizing the spine in the suspected, proves pivotal to the outcome. Conclusions: Adverse slamming dynamics cause accidental injuries in helocasting. Thorax and spine are predominantly traumatized, both directly and indirectly, and are assessed best using CT. Timely spine stabilization and evacuation prove vital. Accurate assessment of height/speed and adherence to their ideal limits, at despatch, may avert such injuries.
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STUDY DESIGN: Retrospective Cohort Study. OBJECTIVE: The aim of this study was to compare the efficacy of CT-based computer assisted navigation (CAN) to conventional pedicle screw placement for patients with Adolescent Idiopathic Scoliosis (AIS). METHODS: This retrospective cohort study drew data from the National Readmissions Database, years 2016-2019. Patients undergoing posterior fusion for AIS, either via CAN or fluoroscopic-guided procedures, were identified via ICD-10 codes. Multivariate regression was performed to compare outcomes between operative techniques. Negative binomial regression was used to asses discharge disposition, while Gamma regression was performed to assess length of stay (LOS) and total charges. Patient demographics and comorbidities, measured via the Elixhauser comorbidity index, were both controlled for in our regression analysis. RESULTS: 28,868 patients, 2095 (7.3%) undergoing a CAN procedure, were included in our analysis. Patients undergoing CAN procedures had increased surgical complications (Odds Ratio (OR) 2.23; P < 0.001), namely, blood transfusions (OR 2.47; P < 0.001). Discharge disposition and LOS were similar, as were reoperation and readmission rates; however, total charges were significantly greater in the CAN group (OR 1.37; P < 0.001). Mean charges were 191,489.42 (119,302.30) USD for conventional surgery vs 268 589.86 (105,636.78) USD for the CAN cohort. CONCLUSION: CAN in posterior fusion for AIS does not appear to decrease postoperative complications and is associated with an increased need for blood transfusions. Given the much higher total cost of care that was also seen with CAN, this study calls into question whether the use of CAN is justified in this setting.