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Background Cortical bone trajectory (CBT) has been well-known in spine surgery for obtaining improved fixation while minimizing soft tissue dissection. This study was designed to compare the bone mineral density (BMD) between the CBT and traditional trajectory (TT) by using Hounsfield unit (HU) values and identify the ideal decades of patients and the suitable lumbar segments using this CBT technology from a radiological standpoint. Methods Patients were selected randomly from an institutional database based on age (evenly distributed by a decade of life) and gender. A total of 240 healthy patients had a computed tomography (CT) scan of the chest, abdomen, and pelvis. For each patient, axial slices of every vertebra were cut in two planes: one horizontal to the pedicle representing the plane wherein pedicle screws were inserted using the TT and the other in a caudocranial plane representing the plane wherein pedicle screws were inserted using the CBT. For each trajectory, a region of interest (ROI) was selected within the area wherein the screws were inserted. A CT number (HU values) was then calculated within each ROI to represent bone density. Results HU values measured at the ROI of CBT were significantly greater than those of the traditional pedicle screw in all age groups, and the specific value (ratio of the HU values of CBT/the HU values of TT) between CBT and TT was 1.92. A significant difference was observed between male and female. The HU values of CBT and TT of males were generally higher than those of females (males: CBT/TT 1.89 ± 0.45; Females: CBT/TT 1.95 ± 0.47). The specific value in HU values significantly increased with increasing age (p = 0.000) and cauda lumbar level (p = 0.000) in males and females. Conclusion BMD, as measured by HU values for the ROI of the CBT screw, was significantly greater than that of the traditional pedicle screw, especially in old patients and cauda lumbar segments.

STUDY DESIGN A retrospective study. OBJECTIVE To compare the accuracy of pedicle screw placement and proximal facet joint violation (FJV) in single-level degenerative lumbar diseases using cortical bone trajectory (CBT) and traditional trajectory (TT) techniques, and analyze their possible risk factors. SUMMARY OF BACKGROUND DATA CBT screws have been utilized increasingly to improve cortical bone contact to prevent screw pullout and reduce approach-related morbidity. However, the studies on intra-pedicular accuracy and proximal FJV between the two methods are rare. METHODS A total of 40 patients who required single-level instruments were included in the retrospective study treated with the CBT-TLIF and the TT-TLIF at a 1:1 ratio from March 2019 to August 2020. The radiographic outcomes were the intra-pedicular accuracy and proximal FJV. Moreover, the possible risk factors were assessed using bivariate and multivariate analyses. RESULTS As for the intra-pedicular accuracy, 73 screws (91.3%) were classified as grade A, 7 screws (8.7%) classified as grade B in the CBT group. A total of 71 screws (88.8%) were graded A with remaining 8 screws (10.0%) graded B and 1 screw (1.2%) graded C in the TT group. The proportion of optimal and clinically acceptable screw positions in the two groups were not significantly different (P > 0.05). In addition, the rate of proximal FJV in CBT approach (8.3%) was significantly lower than that in the TT approach (35.0%) (P

Objective To determine the rates and risk factors of pedicle screw placement accuracy and the proximal facet joint violation (FJV) using TINAVI robot-assisted technique. Methods Patients with thoracolumbar fractures or degenerative diseases were retrospectively recruited from June 2018 and June 2020. The pedicle penetration and proximal FJV were compared in different instrumental levels to identify the safe and risk segments during insertion. Moreover, the factors were also assessed using univariate and multivariate analyses. Results A total of 72 patients with 332 pedicle screws were included in the current study. The optimal and clinically acceptable screw positions were 85.8% and 93.4%. Of the 332 screws concerning the intra-pedicular accuracy, 285 screws (85.8%) were evaluated as Grade A according to the Gertzbein and Robbins scale, with the remaining 25 (7.6%), 10 (3.0%), 6 (1.8%), and 6 screws (1.8%) as Grades B, C, D, and E. Moreover, in terms of the proximal FJV, 255 screws (76.8%) screws were assessed as Grade 0 according to the Babu scale, with the remaining 34 (10.3%), 22 (6.6%), and 21 screws (6.3%) as Grades 1, 2, and 3. Furthermore, the univariate analysis showed significantly higher rate of penetration for patients with age p = 0.007), facet angle ≥ 45° (adjusted OR 0.266, 95% CI 0.090–0.786; p = 0.017), distance from skin to insertion point ≥ 4.5 cm (adjusted OR 0.342, 95% CI 0.134–0.868; p = 0.024), and lumbosacral instrumentation (adjusted OR 0.227, 95% CI 0.091–0.566; p = 0.001) were independently associated with intra-pedicular accuracy; the L5 insertion (adjusted OR 2.020, 95% CI 1.084–3.766; p = 0.027) and facet angle ≥ 45° (adjusted OR 1.839, 95% CI 1.026–3.298; p = 0.041) were independently associated with the proximal FJV. Conclusion TINAVI robot-assisted technique was associated with a high rate of pedicle screw placement and a low rate of proximal FJV. This new technique showed a safe and precise performance for pedicle screw placement in spinal surgery. Facet angle ≥ 45° is independently associated with both the intra-pedicular accuracy and proximal FJV.

This study aims to introduce an innovative adjustable prone positioning frame (APPF) and explore its feasibility and safety for treatment of severe kyphosis secondary to ankylosing spondylitis (AS) with two-level osteotomy.A retrospective, non-controlled study was conducted to illustrate the process where 13 patients diagnosed with severe kyphosis secondary to AS received operations on the APPF. Parameters of chin brow vertical angle (CBVA), global kyphosis (GK), thoracolumbar kyphosis (TLK), lumbar lordosis (LL) and sagittal vertical axis (SVA) were measured. Positioning time, operation time, intraoperative blood loss aḥd complications were also determined. The Scoliosis Research Society outcomes instrument (SRS-22) was applied for clinical assessment.All patients were placed on the APPF successfully with the positioning time of 2.92 ± 0.76 min, received operation with 457.00 ± 88.04 min and had blood loss of 2330.77 ± 1423.25 ml. Four cases experienced pain due to tensional skin of the abdomen and one case suffered cerebrospinal fluid leakage postoperatively, but these patients were all cured conservatively. No neurological complications were observed, although sagittal translation occurred in four patients. Significant improvements were detected in CBVA, GK, TLK, LL and SVA postoperatively (P 0.05), but no significant difference was observed between postoperation and the final follow-up (P 0.05). The SRS-22 scores at 2 years after operation were significantly higher than those before operation (P 0.05).The innovative APPF provided great convenience to place patients with severe kyphosis secondary to AS in a prone position. Performing two-level osteotomy with the aid of APPF is safe, feasible and effective.

A new terahertz (THz) polarization beam splitter (PBS) based on cyclic olefin copolymer (COC) photonic crystal fiber (PCF) with a simple structure is proposed. The dual cores are achieved by introducing six circular air holes in two rows of upper and lower symmetry into the fiber core. The mode coupling characteristics between the even and odd modes for the proposed dual-core PBS are investigated using the time-domain finite-difference (FDTD) method and coupled-mode theory. The influence of geometrical structure parameters on the PBS performance is analyzed. The numerical simulation results reveal that when the incident light frequency is 0.6 THz and the PBS length is 53.88 mm, the bandwidths of 0.0217 THz (from 0.5895 THz to 0.6112 THz) and 0.0225 THz (from 0.5908 THz to 0.6133 THz) are obtained for the x and y-polarization modes, respectively. The highest polarization extinction ratios (ERs) are 114.5 dB and 72.3 dB for the x and y-polarization modes, respectively. The simple structure and wide bandwidth make the proposed PBS will find extensive applications in THz communication, imaging, sensing, metrology, and microscopy.

Background Context Surgical treatment for unstable atlas fractures has evolved in recent decades from C1-C2 or C0-C2 fusion to motion-preservation techniques of open reduction and internal fixation (ORIF). However, regardless of a transoral or a posterior approach, the reduction is still not satisfactory. Purpose The article describes and evaluates a new technique for treating unstable atlas fractures by using a monoaxial screw-rod system. Study Design This is a retrospective study. Patient Sample The sample includes adult patients with unstable C1 fractures treated with a posterior monoaxial screw-rod system. Outcome Measures The outcome measures included a visual analog pain scale, radiographic reduction (lateral mass displacement [LMD]), maintenance of reduction, C1-C2 instability (anterior atlantodens interval), and complications. Materials and Methods From August 2013 to May 2016, nine consecutive patients with unstable atlas fractures were retrospectively reviewed. All patients were treated with posterior ORIF by using a monoaxial screw-rod system. The medical records and the preoperative and postoperative radiographs were reviewed. Preoperative and postoperative computed tomography scans were used to specify the fracture types and to assess the reduction. Results All nine patients with a mean age of 50.3 years successfully underwent surgery with this technique, and a follow-up of 17.4±9.3 months was performed. Transverse atlantal ligament (TAL) injury was found in eight of the nine patients: one of type I and seven of type II. The preoperative LMD averaged 7.0±2.2 mm and was restored completely after surgery; all the fractures achieved bony healing without loss of reduction or implant failure. None of the patients had complications of neurologic deficit, vertebral artery injury, or wound infection associated with the surgical procedure. Two patients complained of greater occipital nerve neuralgia after the operation, which gradually disappeared in 1 month. All patients had a well-preserved range of motion of the upper cervical spine at the final follow-up. Conclusions Posterior osteosynthesis with a monoaxial screw-rod system is capable of an almost anatomical reduction for the unstable atlas fractures. The TAL incompetence may not be a contraindication to ORIF for C1 fractures, but the long-term effect of C1-C2 instability remains to be further investigated.

There is currently no effective treatment to prevent the progress of Alzheimer’s disease (AD). The traditional Chinese herbs Dengzhan Shengmai (DZSM) capsules and their active component scutellarin possess multiple effects and are clinically used for the treatment of cerebrovascular diseases. Scutellarin has been reported to affect Aβ aggregation. However, the effects of DZSM capsules on AD remain unknown. Through in vivo experiments, our study proved that the alleviating effects of DZSM capsules on cognitive deficits of AD mice were due to the role of scutellarin, which up-regulated low toxic amyloid plaques and down-regulated highly toxic soluble Aβ42 and Aβ40 levels in cortex. In vitro, we confirmed scutellarin’s role in accelerating transforming Aβ42 monomers into high-molecular-mass aggregates by biochemical assays, which supported the results observed in drug-treated APP/PS1 mice. In detail, the 1:10 ratio of scutellarin/Aβ42 mixtures promoted production of large β-sheet-rich fibrils whereas the 1:1 ratio promoted production of protofibrils. In addition, the binding between scutellarin and Aβ monomers was quantified by microscale thermophoresis test and the apparent dissociation constant (Kd) was 1284.4 ± 238.8 μM. What’s more, binding regions between scutellarin and Aβ fibrils were predicted by computational docking models and scutellarin might bind parallel to the long axis of Aβ42 fibrils targeting hydrophobic grooves at residues 35–36 or 39. In conclusion, DZSM capsules protected against cognitive defects of AD through scutellarin-mediated acceleration of Aβ aggregation into fibrils or protofibrils and reduction of soluble Aβ oligomers, thus suggesting potential clinical applications of DZSM capsules and scutellarin in the treatment of AD.

A first principles calculation on the electronic properties of α- and β-UH3 is implemented by using a many-body method merging density functional theory (DFT) with dynamical mean field theory (DMFT). Results show that α- and β-UH3 are both in mixed-valent metallic states with an average occupation of 5f electrons nf about 2.418 and 2.520, respectively, and exhibiting strong valance fluctuation due to the quantum superposition of 5f2 and 5f3 configurations in the ground state. The spectrum function demonstrates that U 5f electrons possess the dual characters, i.e., the localized and itinerant behaviors, and the localized 5f counts are 1.106 and 1.112 for α- and β-UH3, respectively, which is well in accord with the experimental observations. The imaginary part of the impurity Green functions reveals that U 5f j = 5/2 and j = 7/2 states both exhibit the metallic and insulating characteristics, respectively. The quasi-particle weight establishes that U 5f j = 5/2 and j = 7/2 states are in the moderately and weakly correlated regimes, respectively, and jj coupling scheme is more feasible as compared to the intermediate coupling (IC) or the Russel-Saunders (LS) coupling regime.

Study design This is a radiographic and cadaveric study. Objective The aim of this study was to conduct a detailed comparison about the parameters between the ideal cortical bone trajectory (CBT) and practical CBT screw. Summary of background data CBT screws have recently become popular in spinal surgery, mainly because of their improved fixation while minimizing soft tissue dissection. However, to our knowledge, no previous study has provided a detailed comparison on the parameters between the ideal CBT and practical CBT screws. Materials and methods The 3-dimensional computed tomography scans of 126 spinal vertebrae separated from 40 lumbar spines were studied. After determining the CBT, the maximal screw length, maximal screw diameter, lateral angle (LA), and cephalad angle (CA) were calculated. Thereafter, CBT screws were inserted into these cadaveric lumbar spines. Subsequently, the lateral angle of screw (LAs) and cephalad angle of screw (CAs) of the screws were measured using 3-dimensional computed tomography. Results As for the ideal CBT, the maximal screw length gradually increased from L1 (32.0 mm) to L4 (35.3 mm) and then decreased at L5 (34.8 mm). Moreover, the maximal screw diameter increased from L1 (4.5 mm) to L5 (7.5 mm). The LA from L1 to L5 were 9.2, 9.4, 9.9, 11.2, and 12.0 degrees, respectively. The CA from L1 to L5 were 25.8, 25.8, 26.3, 26.8, and 26.0 degrees, respectively. As for the actual CBT screw, the LAs from L1 to L5 were 12.7, 14.1, 13.2, 12.4, and 13.0 degrees, respectively. The CAs from L1 to L5 were 25.4, 27.5, 29.2, 30.1, and 30.5 degrees, respectively. Significant differences were observed between the angles of the ideal trajectory and the actual screw. Conclusions Parameters of the actual CBT screw are slightly larger than the optimal trajectory measurements. The CAs and LAs are ∼25-30 and 10-16 degrees, respectively. L1 and L2 should be given considerable attention when using the CBT technique. And the trajectory measurements can only be used as a guide in clinical practice.

Objective Selecting optimal strategies for improving fixation in osteoporotic lumbar spine is an important issue in clinical research. Cortical bone trajectory (CBT) screws have been proven to enhance screw pullout strength, but biomechanical efficacy of these screws remains understudied. The aim of this study was to evaluate biomechanical efficacy of CBT screws in osteoporotic lumbar spine. Methods Thirty-one vertebrae from 14 cadaveric lumbar spines were obtained. All specimens were measured by computed tomography; the diameter of pedicles, excluding those of vertebral bodies with very small pedicle developments, was calculated. After measuring bone mineral density, the CBT screw was randomly inserted into 1 side, and the traditional trajectory (TT) screw was inserted into the contralateral side. Maximum insertional torque was recorded after screw insertion. Of vertebrae, 21 were subjected to pullout testing at a rate of 5 mm/minute, and 10 were subjected to cyclic fatigue testing. Each construct was loaded until exceeding 5 mm. Results Average bone mineral density was 0.567 ± 0.101 g/cm2. CBT screws had higher maximum insertional torque (degrees of freedom = 30, t = 5.78, P Conclusions CBT screws had better biomechanical fixation in osteoporotic lumbar spine compared with standard pedicle screws.

A persistent challenge in spine surgery is improving screw fixation in patients with poor bone quality. Augmenting pedicle screw fixation with allograft bone appears to be a promising approach.To evaluate the biomechanical properties of screws augmented or revised with allograft bone particles (ABPs) and the effect of different sizes and amounts of ABP on screw-fixation strength.Biomechanical in vitro study.Sixty vertebrae were separated randomly into six groups. Groups A1 and A2: one pedicle of each vertebra was selected randomly to be the original pedicle and implanted with a screw. Then, biomechanical tests were performed. Subsequently, the failed trajectory was revised with 1 mm ABP, and the contralateral pedicle was augmented with the same size and amount of ABP. Groups B1 and B2: two pedicles of each vertebra were augmented with different amounts of 1 mm ABP. Groups C1 and C2: one pedicle of each vertebra was augmented with 1 mm ABP to the maximum. The contralateral pedicle of each vertebra was augmented with the same amount of 2 mm ABP. After augmentation and screw insertion, groups A1, B1, and C1 were subjected to the pullout test, whereas groups A2, B2, and C2 the cyclic fatigue test.Groups A1 and A2: screw augmentation increased the pullout strength by 47%, cycles to failure by 31%, and failure loads by 21% compared with the screw in the original pedicle (p.05). Screw revision obtained 79% pullout strength, 97% cycles to failure, and 98% failure loads of the screw in the original pedicle (p.05). Groups B1 and B2: full (100%) trajectory augmentation increased the pullout strength by 39%, cycles to failure by 18%, and failure loads by 12% compared with half (50%) trajectory augmentation (p.05). Groups C1 and C2: the values of the pullout strength, cycles to failure, and failure loads of the screw augmented with 1 mm ABP were all greater than those in the 2 mm ABP. However, no significant differences were observed between the two treatments (p.05).Trajectory augmentation with ABP can significantly increase the strength of the augmented screws. Full trajectory augmentation can provide greater strength compared with half trajectory augmentation. In patients with osteoporosis, we recommend using 1 mm ABP in full trajectory augmentation (0.3 g ABP for 5.5 mm×40 mm and 0.5 g ABP for 6.5 mm×45 mm) before trajectory fails.

The axis body fractures are relatively uncommon and have a variety of presentations. Surgical management to them has been only reported as case reports or included as a minor part of clinical management. The objective of this study is to summarize the indications for surgery and report the clinical outcome of surgical treatment based on different fracture patterns.A retrospective analysis of 28 consecutive patients presenting with the axis body fractures was undertaken. The indications for surgical treatment were defined as: (1) fractures associated with instability of adjacent joints; (2) irreducible displaced superior articular facet fracture; (3) fractures resulting in spinal cord compression. The fractures were classified as sagittal, coronal, transverse and lateral mass fracture. One of the following surgical procedures was applied according to the fracture pattern: posterior C1-C2 pedicle screws fixation and fusion (I); posterior C1-C3 screws fixation and fusion (II); posterior osteosynthesis with C2 transpedicular half-thread lag screws (III).13 patients were successfully managed operatively. Two transverse and two unilateral lateral mass fractures were treated with surgical procedure I, five sagittal fractures with II, four coronal fractures with III. Complications of malposition of screws and neurologic deficit did not occur during operation. Satisfactory reduction and bony union were demonstrated on postoperative radiographics.Conservative treatment is still advocated as primary management for most axis body fractures. But for patients with obvious adjacent joints instability or irreducible displaced superior articular facet fracture, surgical intervention based on the different fracture pattern is necessary.

Taking pure electric vehicle as object, it has been studied for the temperature and over-current in power system of electric vehicles under different working conditions firstly, the sensor location selected also be analyzed. Based on BP neural network method, the tipping point of spontaneous combustion has been estimated through simulation, and the results show that this approach is effective.

Retrospective chart audit.This study aims to compare the clinical features and surgical outcomes in patients with cervical spondylotic myelopathy (CSM) among different age groups.The first Affiliated Hospital of Anhui Medical University, China.A total of 460 patients with CSM who were surgically treated over the period of 1995-2009 were investigated. Considering the peak age (40-60 years old) for the onset of symptoms, we divided the patients into three groups by age: young (40), middle-aged (40-60), and old (60). The differences in symptoms, symptom durations, involved levels, surgical approaches and outcomes were evaluated.The number of symptoms and involved levels, symptom duration and posterior approach significantly increased with increasing age, whereas preoperative Japanese Orthopedic Association score decreased among the three groups. Spinal cord function improved after surgery in all groups. The highest degree of recovery occurred during the first 6 months after surgery, especially within the first week, and then reached a plateau. After 6 months, however, recovery continuously improved, stabilized and declined in the young, middle-aged, old groups, respectively. The recovery rate was not significantly different at an immediate period (1 week) after operation among the three groups, but was significantly different at later periods (3 or more months postoperatively). Three groups showed no difference in postoperative complication rates.The severity of CSM increased with increasing age. Age was inversely correlated with recovery, and recovery decreased as age increased. Six months post operation was the prime time for the recovery of spinal cord function.

The ubiquitin E3 ligase CUL4A plays important roles in diverse cellular processes including carcinogenesis and proliferation. It has been reported that the expression of CUL4A can be induced by hypoxic-ischemic injury. However, the effect of elevated expression of CUL4A on hypoxia-reoxygenation injury is currently unclear. In this study, human CUL4A (hCUL4A) was expressed in rat pheochromocytoma (PC12) cells using adenoviral vector-mediated gene transfer, and the effects of hCUL4A expression on hypoxia-reoxygenation injury were investigated. In PC12 cells subjected to hypoxia and reoxygenation, we found that hCUL4A suppresses apoptosis and DNA damage by regulating apoptosis-related proteins and cell cycle regulators (Bcl-2, caspase-3, p53 and p27); consequently, hCUL4A promotes cell survival. Taken together, our results reveal the beneficial effects of hCUL4A in PC12 cells upon hypoxia-reoxygenation injury.

We hypothesized that activation of the central histaminergic system is required for neuroprotection induced by hypoxic preconditioning. Wild-type (WT) and histidine decarboxylase knockout (HDC-KO) mice were preconditioned by 3 hours of hypoxia (8% O2) and, 48 hours later, subjected to 30 minutes of middle cerebral artery (MCA) occlusion, followed by 24 hours of reperfusion. Hypoxic preconditioning improved neurologic function and decreased infarct volume in WT or HDC-KO mice treated with histamine, but not in HDC-KO or WT mice treated with α-fluoromethylhistidine (α-FMH, an inhibitor of HDC). Laser-Doppler flowmetry analysis showed that hypoxic preconditioning ameliorated cerebral blood flow (CBF) in the periphery of the MCA territory during ischemia in WT mice but not in HDC-KO mice. Histamine decreased in the cortex of WT mice after 2, 3, and 4 hours of hypoxia, and HDC activity increased after 3 hours of hypoxia. Vascular endothelial growth factor (VEGF) mRNA and protein expressions showed a greater increase after hypoxia than those in HDC-KO or α-FMH-treated WT mice. In addition, the VEGF receptor-2 antagonist SU1498 prevented the protective effect of hypoxic preconditioning in infarct volume and reversed increased peripheral CBF in WT mice. Therefore, endogenous histamine is an essential mediator of hypoxic preconditioning. It may function by enhancing hypoxia-induced VEGF expression.

Activation of Toll-like receptors (TLRs) signaling by intestinal microflora-derived bacterial products plays a key role in injury defence for the host. We investigated the role of TLRs activated by intestinal microflora in radiation-induced DNA damage in mice. We analyzed DNA damage induced by 2Gy γ-ray radiation in an intestinal commensal bacteria-depleted mouse model (CD group), in which TLRs (TLR2/6, TLR4 and TLR5) ligand levels in serum were reduced. Chromosomal aberrations were measured in bone marrow cells and peripheral blood leukocyte comet assays were performed. DNA damage was increased in the CD group compared with the control group. Treatment of mice with TLR agonists (CBLB502, LPS and lipopeptide) 1h before radiation resulted in a significant decrease in DNA damage. Genes induced by TLR5 activation were analyzed; activation of TLRs regulated the expression of Gadd45b, Sod2, and Rad21, which are involved in DNA damage repair. In summary, our data indicate that TLRs activation by intestinal microflora reduces DNA damage induced by radiation and regulates expression of several DNA repair genes.

Morphology‐dependent stimulated Raman scattering is a nonlinear laser Raman spectroscopy that relies on using the cavity modes associated with micron‐sized structures to enhance optical signal generation. Since different cavity modes occupy different regions in space, location‐specific spectra can be generated. Here we outline the physics behind morphology‐dependent stimulated Raman scattering imaging and model the signal generation process. The results show that a simple tailoring of the illumination conditions allows signal from single, but selectable, cavity modes to be generated. Thus, this nonlinear Raman technique can be used to image spatial variations in chemical composition and/or molecular structure within microstructures.

Experimental confirmation that morphology‐dependent stimulated Raman scattering can be used as an optical imaging technique is given. The water structure variations present at a charged water/air interface have been mapped. The measured structure variations track precisely that given by the Gouy–Chapman theory. We present, to our knowledge, the first experimental investigations of water solvent response in the diffuse part of the electric double layer. Imaging experiments on droplets charged to both positive and negative values have enabled us to determine the neutral water/air interface potential.

Morphology-dependent stimulated Raman scattering (MDSRS) has been used to monitor the degree of hydrogen bonding in water aerosols generated by a vibrating orifice aerosol generator (VOAG). The results show that aerosols created by a VOAG suffer extensive structural disruption and that the disruption is most pronounced at the aerosol surface. Laboratory aerosols prepared in this way do not appropriately mimic those found in the atmosphere, and the mass accommodation coefficients measured using such aerosols should not be used in global climate modeling calculations. 25 refs., 10 figs.

We reported a 2-year-old boy with developmental delay, mild mental retardation, and severe craniofacial malformation, including facial asymmetry with hypoplasia of the left zygoma, maxilla, and mandible, and left anophthalmia and anotia. A genome-wide screen revealed a 1.38 Mb duplication on chromosome 1q31.1, which was absent in his parents and 27 healthy controls. The duplication region contains two Refseq genes, PLA2G4A and C1orf99, which have not been reported to be implicated in craniofacial malformation. Functional studies of these genes and additional clinical analysis are necessary to elucidate the pathogenesis of craniofacial malformation.

Background It has been demonstrated that cerebral ischemia induces astrocyte reactivity, and subsequent glial scar formation inhibits axonal regeneration during the recovery phase. Investigating the mechanism of glial scar formation will facilitate the development of strategies to improve axonal regeneration. However, an in vitro model of ischemia-induced glial scar has not yet been systematically established. Methodology and Principal Findings In the present study, we at the first time found that oxygen-glucose deprivation (OGD) in vitro can induce rat cortical astrocytes to present characteristics of glial scar. After OGD for 6 h, astrocytes showed a remarkable proliferation following 24 h reperfusion, evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and BrdU immunocytochemistry. Meanwhile, the expression of glial fibrillary acidic protein significantly increased, so did the expression of neurocan, which is a hallmark of the glial scar. In further experiments, neurons were co-cultured with astrocytes, which had been exposed to OGD, and then the immunostaining of class III β-tubulin was carried out to assess the neurite growth. When the co-culture was performed at 48 h reperfusion of astrocytes, the neurite growth was obviously inhibited, and this inhibition could be reversed by chondroitinase ABC, which digests glycosaminoglycan chains on CSPGs, including neurocan. However, the processes of neurons were elongated, when the co-culture was performed immediately after OGD. Conclusions and Significance Our results indicated that after conditioned OGD the astrocytes presented the characteristics of the glial scar, which are also comparable to the astrocytes in acute and chronic phases after cerebral ischemia in vivo. Therefore, the present system may be used as an in vitro model to explore the mechanisms underlying glial scar formation and the treatments to improve axonal regeneration after cerebral ischemia.

A novel non-linear Raman spectroscopic technique, which can be used to characterize the chemical composition of the interface region of volatile aerosol particles, is described. The technique is morphology-dependent stimulated Raman scattering (MDSRS). We discuss the phenomenology behind this new optical probe, and present experimental results which show that this technique can be used as quantitative spectroscopic tool. We outline the potential application of MDSRS to in situ gas—aerosol kinetics and dynamics studies.

A novel nonlinear Raman spectroscopic technique, which can be used to monitor the chemical composition of an aerosol particle interface, is described. The technique is called morphology‐dependent stimulated Raman scattering (MDSRS). Experimental results show that there is a quantifiable relation between MDSRS signal size and the concentration of species being probed. We outline the analytic form of the nonlinear gain equation and prove its reliability by modeling MDSRS signal strengths.

Oculo-auriculo-vertebral spectrum (OAVS) is a common developmental disorder involving first and second pharyngeal arches. Although some family cases and such patients showing chromosomal aberrations suggest that OAVS have a genetic basis, no consistent genetic defects have been recorded at present time. Thus, we conducted genetic studies of a three-generation family with five OAVS patients to identify a causative variant for OAVS. Cytogenetic studies revealed those family members had a normal karyotype and no causative mutations were founded in SALL1 and TCOF1, which known to be responsible for two other syndromes that have clinical overlapping with OAVS. Genotyping with commercially available BeadChips was performed on 13 individuals in the same family, showing no significant difference between the affected and normal members in terms of copy number variations (CNVs) in either number or size and no definitive causative CNV. A total of 8,224 informative autosomal SNPs that are evenly distributed throughout the genome were selected for both parametric and non-parametric linkage analysis. Significant negative LOD scores were obtained for the reported OAVS locus, providing further evidence for genetic heterogeneity of this complex disorder. The highest LOD score of 1.60 was noted on chromosome 15q26.2-q26.3 showing a potential linkage to this locus. The variable phenotypes of the affected members and the failure to identify a causative variant indicate that a complex etiology may be present even in a consanguineous family, which makes it more challenging to ascertain the cause of OAVS in further analysis.

To explore the feasibility of C1-2 pedicle screw fixation and fusion technique in treating atlantoaxial instability.From January 2006 to January 2009,18 patients with atlantoaxial instability were treated with C1-2 pedicle screws and plates fixation under general anesthesia. There were 11 males and 7 females, the age for 17-62 years with the mean of 37.7 years. The course of disease was from 3 days to 30 months with an average of 10.6 months. The patients had different degrees neck pain and disturbance of sensation or (and) dyskinesia, had atlantoaxial instability from images before operation. The JOA scoring before operation were from 8 to 15 with an average of 11.4. Bone fusion of patients was observed with X-rays, CT and MR image at the same time after operation and the JOA scoring was compared with preoperative.A total of 72 screws were successfully placed in 18 cases, among them, 15 cases were followed up from 6 to 24 months with an average of 11.5 months. Fifteen cases obtained bone fusion with time for 3-6 months without the complications of internal fixation failure or redislocation of atlas. The spinal compression had differently improved, postoperative JOA scoring was from 12 to 17 scores with an average of 14.5 scores.Pedicle screw fixation and fusion in atlas has advantages of firm fixation and high fusion rate, it is a better choices for atlantoaxial instability. It is not suitable for variations of sulcus of vertebral artery of atlas and posterior arch of atlas.

Glial scar formed by central nervous system (CNS) injury is the main inhibitory barrier of nerve regeneration. How to promote axonal regeneration after injury,how to accelerate neural network reconstruction and how to improve brain function recovery have become a hot problem to be solved in the field of neuroscience. This article focuses on the recent advances of therapeutic strategies for axonal regeneration.

Recently, we showed that carnosine protects against NMDA-induced excitotoxicity in differentiated PC12 cells through a histaminergic pathway. However, whether the protective effect of the carnosine metabolic pathway also occurs in ischemic brain is unknown. Utilizing the model of permanent middle cerebral artery occlusion (pMCAO) in mice, we found that carnosine significantly improved neurological function and decreased infarct size in both histidine decarboxylase knockout and the corresponding wild-type mice to the same extent. Carnosine decreased the glutamate levels and preserved the expression of glutamate transporter-1 (GLT-1) but not the glutamate/aspartate transporter in astrocytes exposed to ischemia in vivo and in vitro. It suppressed the dissipation of Delta Psi(m) and generation of mitochondrial reactive oxygen species (ROS) induced by oxygen-glucose deprivation in astrocytes. Furthermore, carnosine also decreased the mitochondrial ROS and reversed the decrease in GLT-1 induced by rotenone. These findings are the first to demonstrate that the mechanism of carnosine action in pMCAO may not be mediated by the histaminergic pathway, but by reducing glutamate excitotoxicity through the effective regulation of the expression of GLT-1 in astrocytes due to improved mitochondrial function. Thus, our study reveals a novel antiexcitotoxic agent in ischemic injury.

We describe a patient with multiple congenital anomalies, including hemifacial microsomia, asymmetric macrostomia, dysplastic mandible, multiple preauricular tags, atresia of the external auricular canal, and vertebral anomalies, which coincide with oculo-auriculo-vertebral spectrum. G-banding ( approximately 850 band level) showed a normal 46, XY karyotype. A genome-wide screen for copy number variations (CNVs) using single nucleotide polymorphism (SNP) arrays revealed a 1Mb and a 167 kb deletion both on chromosome 5q13.2, which were absent in the parents and in 27 controls. Sixteen genes were located in the deleted region, including BIR1C and OCLN, which are involved in apoptosis. Haploinsufficiency of these genes may be contributing to the phenotype in this patient. To our knowledge, there are no previous reports of this 5q13.2 deletion in a patient with oculo-auriculo-vertebral spectrum.

To explore the clinical features, treatment and prognosis of the C5 palsy after surgery of cervical spondylosis.Two hundred and twenty-three cases treated from March 1994 to October 2003 were retrospectively reviewed.Seven of the 223 cases developed the complication of C5 palsy, manifesting the paresis of the deltoid muscle as well as the sensory deficits and (or) intractable pain in shoulder. The incidence was 3.1%. In this study, 2 cases occurred in the anterior subcorpectomy, 5 cases developed in the laminoplasty with 1 case on the opened side, 3 cases on the hinged side and 1 case on both sides. All the 7 cases with the C5 palsy recovered within 2 weeks to 6 months.The C5 palsy can develop either anterior decompression or posterior open-door laminoplasty of cervical spondylosis. Generally speaking, patients with postoperative C5 palsy can be cured by conservative measures. And prognosis is good.

Coherent anti-Stokes Raman scattering (CARS) spectroscopy has been used to detect the v[sub 1] fundamental of gas-phase ClO[sub 2]. CARS detection limits are reported. The results show that the CARS technique is ideally suited for gas-phase ClO[sub 2] photodissociation dynamics studies. 25 refs., 1 fig.

Recent experiments done in our laboratory provided a preliminary indication that morphology- dependent stimulated Raman scattering could be used to spatially image molecular structure and composition changes in regions located close to the surface of axisymmetric particles. We have just completed a new series of theoretical and experimental studies which confirm our initial results. The results of these studies are described here.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.