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This paper presents a framework governing multiple state machines (SMs) to generate behaviors for kinematically-coupled multi-arm robots. A SM is one of the most used tools to switch controllers in robotics, however, it represents only one motion at a certain time. Such a limit of representation not only restricts the potential of the kinematical redundancy but also significantly increases the number of situations we have to consider in behavior design. To relax the problem, this paper provides a distributed design scheme and an online synthesis method for SMs. The base of the framework is a task-priority-based control method for redundant robots. We expand it by introducing an abstract data structure specialized in robotic behaviors. The abstract reformulation naturally connects with SMs so that the framework realizes parallelism of sequential logic. A priority queue constructed in each control loop integrates SMs designed for each effector, and the framework automatically generates whole-body behaviors online. In dynamic simulations, the framework governs four SMs and achieves reaching tasks with a dual-arm manipulator at 1 kHz. It is shown that the loose coupling of the SMs yields reactive and flexible decisions in a dynamic environment.

OBJECTIVE Proximal junctional kyphosis (PJK), which can worsen a patient’s quality of life, is a common complication following the surgical treatment of adult spinal deformity (ASD). Although various radiographic parameters have been proposed to predict the occurrence of PJK, the optimal method has not been established. The present study aimed to investigate the usefulness of the T1–L1 pelvic angle in the standing position (standing TLPA) for predicting the occurrence of PJK. METHODS The authors retrospectively extracted data for patients with ASD who underwent minimum 5-level fusion to the pelvis with upper instrumented vertebra between T8 and L1. In the present study, PJK was defined as ≥ 10° progression of the proximal junctional angle or reoperation due to progressive kyphosis during 1 year of follow-up. The following parameters were analyzed on whole-spine standing radiographs: the T1–pelvic angle, conventional thoracic kyphosis (TK; T4–12), whole-thoracic TK (T1–12), and the standing TLPA (defined as the angle formed by lines extending from the center of T1 and L1 to the femoral head axis). A logistic regression analysis and a receiver operating characteristic curve analysis were performed. RESULTS A total of 50 patients with ASD were enrolled (84% female; mean age 74.4 years). PJK occurred in 19 (38%) patients. Preoperatively, the PJK group showed significantly greater T1–pelvic angle (49.2° vs 34.4°), conventional TK (26.6° vs 17.6°), and standing-TLPA (30.0° vs 14.9°) values in comparison to the non-PJK group. There was no significant difference in the whole-thoracic TK between the two groups. A multivariate analysis showed that the standing TLPA and whole-thoracic TK were independent predictors of PJK. The standing TLPA had better accuracy than whole-thoracic TK (AUC 0.86 vs 0.64, p = 0.03). The optimal cutoff value of the standing TLPA was 23.0° (sensitivity 0.79, specificity 0.74). Using this cutoff value, the standing TLPA was the best predictor of PJK (OR 8.4, 95% CI 1.8–39, p = 0.007). CONCLUSIONS The preoperative standing TLPA was more closely associated with the occurrence of PJK than other radiographic parameters. These results suggest that this easily measured parameter is useful for the prediction of PJK.

A new concept of a dynamical system representation is proposed. The idea of the representation is simple: combination of nonlinear coordinate transformation and time scale transformation. Introducing a projected referential trajectory and a moving frame on it, the coordinate transformation separates a system state into sub-states tangent to the trajectory and orthogonal one. Then time scale transformation using the arc length of the trajectory yields a state equation in which the state evolves spatially around the trajectory. As one of the advantages of the proposed method, time scale transformation enables us to ignore dynamics of the tangent sub-state at the same time. Therefore, the proposed representation realizes one-degree model reduction for smooth control systems. Since all transformation used in this article is invertible, this reduction is recoverable.

Trimethyltin (TMT) has been used as a cytotoxin to neurons rather than glial cells in the mammalian hippocampus. The systemic administration of TMT led to declined fluorescence of ZnAF-2 DA staining as a marker of intact mossy fibers and increased fluorescence of Fluoro-Jade B staining as a marker of degenerated neurons during the initial 2 to 5 days after the administration with later ameliorations within 30 days in the hippocampal dentate gyrus (DG) and CA3 region in mice. On immunoblotting analysis, both GABA

Retrospective observational study.This study examined associated factors for the improvement in spinal imbalance following decompression surgery without fusion.Several reports have suggested that decompression surgery without fusion may have a beneficial effect on sagittal balance in patients with lumbar spinal stenosis (LSS) through their postoperative course. However, few reports have examined the association between an improvement in sagittal imbalance and spinal sarcopenia.We retrospectively reviewed 92 patients with LSS and a preoperative sagittal vertical axis (SVA) more than or equal to 40 mm who underwent decompression surgery without fusion at a single institution between April 2017 and October 2018. Patients' background and radiograph parameters and the status of spinal sarcopenia, defined using the relative cross-sectional area (rCSA) of the paravertebral muscle (PVM) and psoas muscle at the L4 caudal endplate level, were assessed. We divided the patients into two groups: those with a postoperative SVA less than 40 mm (balanced group) and those with a postoperative SVA more than or equal to 40 mm (imbalanced group). We then compared the variables between the two groups.A total of 29 (31.5%) patients obtained an improved sagittal imbalance after decompression surgery. The rCSA-PVM in the balanced group was significantly higher than that in the imbalanced group (P = 0.042). The preoperative pelvic incidence (PI)-lumbar lordosis (LL) mismatch (P = 0.048) and the proportion with compression vertebral fracture (P = 0.028) in the balanced group were significantly lower than those in the imbalanced group. A multivariate logistic regression analysis identified PI-LL less than or equal to 10° and rCSA-PVM more than or equal to 2.5 as significant associated factor for the improvement in spinal imbalance following decompression surgery.A larger volume of paravertebral muscles and a lower PI-LL were associated with an improvement in sagittal balance in patients with LSS who underwent decompression surgery.Level of Evidence: 3.

A new optimal formulation of the selective cell-based smoothed finite element method using 10-node tetrahedral elements (SelectiveCS-FEM-T10) is proposed for nearly incompressible large deformation problems. SelectiveCS-FEM-T10 is a generic name for S-FEM formulations that apply the selective reduced integration (SRI) and the cell-based S-FEM (CS-FEM) simultaneously to the 10-node tetrahedral (T10) elements, and thus it has various formulation variations. The conventional SelectiveCS-FEM-T10 naturally subdivides a T10 element into twelve 4-node tetrahedral (T4) subelements with a dummy node at the element center. Meanwhile, the new SelectiveCS-FEM-T10 radially subdivides it into sixteen T4 subelements around the dummy node. Owing to this radial element subdivision, all the edges of the subelements, including the frame edges, are subjected to strain smoothing only via the edge-based S-FEM (ES-FEM) within an element. Besides, SelectiveCS-FEM-T10 can be implemented into general finite element codes as a T10 element because it is a CS-FEM, which only applies intra-element strain smoothing. Our demonstrative analyses reveal that the new SelectiveCS-FEM-T10 is more robust than the best available T10 element against severe large deformation. They also show that the accuracy of the new SelectiveCS-FEM-T10 is almost equal to the conventional T10 elements as it does not cause shear/volumetric locking and pressure checkerboarding.

Study design This was a retrospective observational study. Objective The aim of this study was to evaluate the efficacy of our new protocol for preventing postoperative surgical site infection (SSI) following spinal surgery. Summary of background data SSI following spinal surgery is a serious postoperative complication. Several studies have recently assessed the effectiveness of wound irrigation with povidone-iodine (PVP-I) for SSI prevention, but no consensus has been reached as to how PVP-I should be used in clinical practice. We formed a PVP-I irrigation protocol focusing on the pharmacological properties of PVP-I. This study aimed to evaluate the efficacy and safety of our protocol for preventing SSI. Materials and methods All cases of spinal surgery at our hospital between October 2011 and September 2016 were retrospectively reviewed. The exclusion criteria were PVP-I allergy, prior surgical debridement for infection, and implant removal surgery. The patients were subdivided into those who had received normal saline irrigation after 90 seconds of 1% PVP-I pooling every 1.5 hours (study group) or only routine saline irrigation every 1.5 hours (control group). The study and control groups comprised of 177 and 146 patients, respectively. This study compared the rate of SSI with and without the use of the PVP-I irrigation protocol. Results The SSI rates were 1.7% for the study group (3/177 patients) and 3.4% for the control group (5/146 patients), showing no significant statistical difference (P=0.32). There were no cases of deep SSI in the study group, whereas there were 4 cases in the control group. The deep SSI rate significantly decreased in the study group (P=0.027). No adverse events occurred in the study group. Conclusion In this study, 90 seconds of 1% PVP-I pooling every 1.5 hours followed by saline irrigation demonstrated the effectiveness of our protocol for the prevention of postoperative deep SSI after spinal surgery.

Cu electroplating is important in LSI manufacturing. In the manufacturing process, some additives are added to a copper sulfate solution. The additive that reduces a deposition rate is called suppressor. Polyethylene Glycol (PEG) has been actively studied as a typical suppressor. PEG adsorbs to the electrode in the presence of a chloride ion and suppresses the deposition rate. The dynamics of adsorption and the mechanism of the suppression effect have been studied, and various mathematical models have been proposed from these results. However, the phenomena have not been perfectly understood and the conventional mathematical models cannot fully reproduce these phenomena.[1] Voltammetry is often performed to observe the behavior of the additives. The rotating disc electrode(RDE) is used in order to control the concentration on the electrode surface. The RDE can control and evaluate the concentration on the electrode surface under the assumption for uniform distribution of concentration and current density on the electrode surface. However, it is observed that the adsorption of PEG occurs non-uniformly on the electrode surface.[2] The voltammogram show dynamics of the current density averaged on the working electrode. It is important to know the local current density and its distribution on the working electrode in order to understand the adsorption dynamics of PEG and the suppression of copper deposition. On the other hand, “Inverse Problems” have attracted attention due to the development of numerical simulation. Inverse Problems is a research area dealing with finding out unknown information from external or indirect observation through a system model. In the fields of electrochemical engineering, there are many problems which can have a benefit from the inverse analysis approach. Using an approach of the Inverse Problems, we identify the current density distribution on the electrode surface. Currents are measured by changing potential and PEG concentration with an electrochemical flow cell. Observation data such as potential, bulk concentration, average flow velocity, and current are used for the inverse analysis. From these observation data, we identify the current density distribution with estimating the models that represent the adsorption dynamics of PEG and the suppression effect of the copper deposition. The figure shows a procedure of the inverse analysis method. The method consists of an experiment and a numerical simulation as shown. In the experiment, observation data are obtained with the electrochemical flow cell. The experimental system consists of two solution supply devices and the electrochemical flow cell.The solution supply device can arbitrarily control a flow rate of the solution supplied to the flow cell. Copper sulfate solutions with different concentrations of PEG are prepared for the solution supply devices. The experimental system can continuously change PEG concentration supplied to the flow cell by changing a mixing ratio of the two solutions. Currents are measured with a linear sweep of potential under constant PEG concentration and a linear sweep of PEG concentration under constant potential. Potential, concentration, average flow velocity, and current are obtained as observation data. In the numerical simulation, the adsorption dynamics of PEG and the suppression of copper deposition are treated in order to express the phenomena related to PEG. Surface coverage of PEG is introduced to express the adsorption dynamics. In this study, the dynamics of the surface coverage is represented by a piecewise linear function with current density, PEG concentration, and surface coverage. The suppression of copper deposition is expressed by the piecewise linear function with surface coverage, copper ion concentration, potential. A velocity field is modeled by the Navier-Stokes equation, and concentration fields of copper ion and PEG are modeled by the advection-diffusion equation. Boundary conditions of the advection-diffusion equation at the electrode are given by the models representing the adsorption dynamics of PEG and the suppression effect of copper deposition. The current density distribution on the electrode surface is evaluated with solving the advection-diffusion equation. The numerical simulation described above can be performed by assuming the parameters of these models. Currents are calculated with solving the advection-diffusion equation under the same potential, concentration, and average flow velocity as the experiment. The parameters of the models can be obtained by minimizing the residual between measured and calculated currents with a nonlinear least squares method. After the model is identified, the current density distribution on the electrodes is easily calculated by the direct analysis. [1]Liu Yang, Aleksandar Radisic, Johan Deconinck, and Philippe M. Vereeckena; J. Electrochem. Soc., 161(5) D269-D276(2014) [2]D. Josell and T. P. Moffat; J. Electrochem. Soc., 163(7) D322-D331(2016) Figure 1

An imbalance of branched‐chain amino acids (BCAAs) in the brain may result in neuropathological conditions, such as autism spectrum disorders. The L‐type amino acid transporter 1 (LAT1), encoded by the solute carrier transporter 7a5 (Slc7a5) gene, is critical for maintaining normal levels of BCAAs in the brain. However, our understanding of the mechanisms that regulate the expression of LAT1/Slc7a5 in neurons is currently limited. Here, we demonstrate that hypoxic conditions result in upregulated expression of Slc7a5 in differentiated neuronal cells (Neuro2A cells induced to differentiate using all‐trans retinoic acid). Mechanistically, hypoxia‐induced expression of Slc7a5 is markedly reduced by short hairpin RNA (shRNA)‐mediated knockdown of hypoxia‐inducible factor 2α (HIF‐2α), but not by shRNA targeting HIF‐1α, in differentiated neuronal cells. Moreover, hypoxia increased the binding of HIF‐2α to the proximal promoter of Slc7a5 in differentiated neuronal cells. These results indicate that hypoxia directly enhances the recruitment of HIF‐2α to the proximal promoter of Slc7a5, resulting in its upregulated expression in differentiated neuronal cells. These findings indicate that Slc7a5 may be a novel gene responsive to hypoxia in a HIF‐2α‐dependent manner in differentiated neuronal cells.

Nucleotide excision repair (NER) is a versatile DNA repair pathway, which can remove an extremely broad range of base lesions from the genome. In mammalian global genomic NER, the XPC protein complex initiates the repair reaction by recognizing sites of DNA damage, and this depends on detection of disrupted/destabilized base pairs within the DNA duplex. A model has been proposed that XPC first interacts with unpaired bases and then the XPD ATPase/helicase in concert with XPA verifies the presence of a relevant lesion by scanning a DNA strand in 5′-3′ direction. Such multi-step strategy for damage recognition would contribute to achieve both versatility and accuracy of the NER system at substantially high levels. In addition, recognition of ultraviolet light (UV)-induced DNA photolesions is facilitated by the UV-damaged DNA-binding protein complex (UV-DDB), which not only promotes recruitment of XPC to the damage sites, but also may contribute to remodeling of chromatin structures such that the DNA lesions gain access to XPC and the following repair proteins. Even in the absence of UV-DDB, however, certain types of histone modifications and/or chromatin remodeling could occur, which eventually enable XPC to find sites with DNA lesions. Exploration of novel factors involved in regulation of the DNA damage recognition process is now ongoing.

We explore BouncyScreen, an actuated 1D display system that enriches indirect interaction with a virtual object by pseudo-haptic feedback mechanics enhanced through the screen's physical movements. We configured a proof-of-concept prototype of BouncyScreen with a flat-screen mounted on a mobile robot. When the user manipulates a virtual object using virtual reality (VR) controllers, the screen moves in accordance with the virtual object. We conducted psychophysical studies to examine how BouncyScreen's physical movements would affect users' pseudo-haptic perceptions and interaction experiences. Our preliminary study using a weight discrimination task for object pushing interaction showed that BouncyScreen offers identical pseudo-force feedback to the vision-based pseudo-haptic technique. We conducted a follow-up psychophysical study using a weight magnitude estimation task for object pushing and bumping interactions. The results reveal that a users' perceived weight magnitude is enhanced by the screen's physical motion under different characteristics depending on interaction styles (i.e., pushing and bumping). Our study also confirmed that the screen's synchronous physical motions significantly enhance the reality of the interaction and the sense of presence. We close this paper with some applications and use suggestions for BouncyScreen in future HMD-free flat-screen 3D user interface systems.

While a change in the pelvic incidence (PI) after long spine fusion surgery has been reported, no studies have examined the change in the PI on the operating table. The present study examined the PI-change on the operating table and elucidated the patients’ background characteristics associated with this phenomenon. This study included patients who underwent lumbar posterior spine surgery and had radiographs taken in a full-standing position preoperatively and a pelvic lateral radiograph in the prone position in the operative room. The patients with PI-change on the operating table (PICOT; PICOT group) and without PICOT (control group) were compared for their background characteristics and preoperative radiographic parameters. There were 128 eligible patients (62 males, 66 females) with a mean age (± standard deviation) of 69.9 ± 11.7 (range: 25–93) years old. Sixteen patients (12.5%) showed a decrease in the PI > 10°, which indicated placement in the PICOT group. The preoperative lumbar lordosis (LL) and PI-LL in the PICOT group were significantly worse than those in the control group (LL: 20.8 ± 16.6 vs. 30.6 ± 16.2, p = 0.0251, PI-LL: 33.9 ± 19.0 vs. 17.3 ± 14.8, p

A new concept of smoothed finite element method (S-FEM) using 10-node tetrahedral (T10) elements, CS-FEM-T10, is proposed. CS-FEM-T10 is a kind of cell-based S-FEM (CS-FEM) and thus it smooths the strain only within each T10 element. Unlike the other types of S-FEMs [node-based S-FEM (NS-FEM), edge-based S-FEM (ES-FEM), and face-based S-FEM (FS-FEM)], CS-FEM can be implemented in general finite element (FE) codes as a piece of the element library. Therefore, CS-FEM-T10 is also compatible with general FE codes as a T10 element. A concrete example of CS-FEM-T10 named SelectiveCS-FEM-T10 is introduced for large deformation problems of nearly incompressible solids. SelectiveCS-FEM-T10 subdivides each T10 element into 12 four-node tetrahedral (T4) subelements with an additional dummy node at the element center. Two types of strain smoothing are conducted for the deviatoric and hydrostatic stress evaluations and the selective reduced integration (SRI) technique is utilized for the stress integration. As a result, SelectiveCS-FEM-T10 avoids the shear/volumetric locking, pressure checkerboarding, and reaction force oscillation in nearly incompressible solids. In addition, SelectiveCS-FEM-T10 has a relatively long-lasting property in large deformation problems. A few examples of large deformation analyses of a hyperelastic material confirm the good accuracy and robustness of SelectiveCS-FEM-T10. Moreover, an implementation of SelectiveCS-FEM-T10 in the FE code ABAQUS as a user-defined element (UEL) is conducted and its capability is discussed.

The measurement of polarization characteristics is important for products and processes such as corrosion inhibition, fuel cell, advanced electroplating and so on. When the current density increases during the polarization curve measurement, the concentration of reactive species distributes non-uniformly. In order to control the concentration on the surface of the electrode, rotating disc electrode (RDE) is sometimes applied. However, even the application of RDE, the non-uniformity of concentration distribution on the surface of the electrode is still remained. Accurate evaluation of concentration flux distribution on the surface of electrode is highly desired. Recently, application of numerical simulation methods such as boundary element method (BEM) or finite element method (FEM) to the electrochemistry problems has been studied intensively, and these methods have become powerful tools. With the progress of numerical simulation, “Inverse Problems” have received a lot of attention. Inverse Problem is a research area dealing with finding out unknown information from external or indirect observation through the model of the system. The background of inverse problems is the modeling and simulation of natural phenomena. When observations are taken of these phenomena, the observation data are used to infer knowledge about physical states. One of the most spectacular success in the field of inverse problems was the invention of an inversion algorithm for Computed Tomography. Not only the computed tomography in medical area, applications of inverse problems arise in many fields of engineering, too. In the fields of electrochemical engineering, there are many problems which can have a benefit from inverse analysis approach. Our research focuses on the techniques for monitoring the accurate current density distribution and concentration distribution on the surface of the electrode during the polarization characteristic measurement. We have developed a novel technique to identify current density and concentration distribution just on the electrode surface from the data of total current, bulk concentration and bulk flow rate. In order to measure total currents, we use electrochemical flow cell that can control bulk flow rate. In this inverse analysis, the concentration distribution on the electrode surface, i.e., boundary conditions of boundary value problem with advection diffusion equation are not fully given, but the total currents and bulk concentration are obtained by practical measurement to compensate for lack of unknown boundary conditions. The solution would be abnormally unstable due to the ill posedness. Hence, let us make use of the a-priori information that concentration and its flux proportional to the current density on the electrode must satisfy the polarization characteristics. we will approximate the polarization characteristics by a function of the concentration and its flux, e.g., piecewise bi-linear function with several number of parameters. Firstly, the velocity field of the flow cell is analyzed with finite volume method as shown at top-right in the figure. The velocity filed is described with Navier-Stokes equation. The figure represents the procedure of the whole inverse analysis. Assuming parameters of polarization characteristics, the direct analysis is performed and total currents is calculated. Minimizing the residual between the measured and the calculated total currents with nonlinear least square method, the parameters of polarization characteristics can be obtained. After obtaining the polarization characteristics, the concentration and the current density distribution on the electrode are easily calculated by the direct analysis. Our primary aim is to verify the applicability of the inverse analysis in the estimation of the polarization characteristics. In order to concentrate on the evaluation of process, we have created necessary measured data through a regular/direct numerical simulation instead of carrying out real experimental measurements. Such a procedure allows the present technique to be isolated from other factors such as unexpected measurement or simulation model error. Up on this, to accommodate an important aspect of experimental measurements, a small perturbation/error is added to the calculated results. These values are assumed as the measured data and used in the inverse analysis to determine the polarization characteristics. The final identified results by the proposed technique are in good agreement with the results computed by the numerical simulation. In order to demonstrate the effectiveness of this technique, the identification using real experimental data is also performed. Figure 1

Summary The mechanistic/mammalian target of rapamycin complex 1 (mTORC1) regulates cellular function in various cell types. Although the role of mTORC1 in skeletogenesis has been investigated previously, here we show a critical role of mTORC1/4E-BPs/SOX9 axis in regulating skeletogenesis through its expression in undifferentiated mesenchymal cells. Inactivation of Raptor, a component of mTORC1, in limb buds before mesenchymal condensations resulted in a marked loss of both cartilage and bone. Mechanistically, we demonstrated that mTORC1 selectively controls the RNA translation of Sox9, which harbors a 5′ terminal oligopyrimidine tract motif, via inhibition of the 4E-BPs. Indeed, introduction of Sox9 or a knockdown of 4E-BP1/2 in undifferentiated mesenchymal cells markedly rescued the deficiency of the condensation observed in Raptor-deficient mice. Furthermore, introduction of the Sox9 transgene rescued phenotypes of deficient skeletal growth in Raptor-deficient mice. These findings highlight a critical role of mTORC1 in mammalian skeletogenesis, at least in part, through translational control of Sox9 RNA., Highlights • mTORC1 controls skeletogenesis both in skeletogenic progenitors and in chondrocytes • mTORC1/4E-BPs cascade regulates the translation of Sox9 RNA • SOX9 is a critical mediator in the control of skeletogenesis by mTORC1 in vivo, Iezaki et al. demonstrated that the mTORC1/SOX9 axis has essential roles in skeletal development through its expression in undifferentiated mesenchymal cells in vivo. Moreover, they identified that mTORC1/4E-BPs cascade regulates the translation of Sox9 RNA in undifferentiated mesenchymal cells, highlighting a critical role of mTORC1/4E-BPs/SOX9 axis in regulating mammalian skeletogenesis.

Among the elderly, even minor injuries can cause cervical spine fractures. With the increasing number of nonagenarians, the opportunities for treatment of cervical spine injuries in nonagenarians are getting to be more common. Conservative therapy is often chosen in nonagenarians with cervical spine injuries because of high risk associated with surgical treatment; however, we present herein the cases of three patients in nonagenarians who underwent surgical treatment for cervical spine injury. After a fall, three cases of nonagenarians who lived alone and independent were diagnosed with a Jefferson fracture and minor dislocated type II odontoid fracture, a C4 fracture with diffuse idiopathic skeletal hyperostosis, and a fracture-dislocation of C2, respectively. Their past medical history included several diseases, but we decided that spine surgery under general anesthesia was acceptable based on their pre-injury condition. We performed posterior fixation for all cases. As a result, while two patients developed postoperative minor complications, all cases showed favorable postoperative courses. They acquired independent or partially assisted walking and were transferred to the hospital for rehabilitation. If fundamental activity of daily living and general condition permit, posterior fixation seems to be a good choice even in nonagenarians.

The availability of amino acid in the brown adipose tissue (BAT) has been shown to be altered under various conditions; however, little is known about the possible expression and pivotal role of amino acid transporters in BAT under physiological and pathological conditions. The present study comprehensively investigated whether amino acid transporters are regulated by obesogenic conditions in BAT in vivo. Moreover, we investigated the mechanism underlying the regulation of the expression of amino acid transporters by various stressors in brown adipocytes in vitro. The expression of solute carrier family 38 member 1 (Slc38a1; gene encoding sodium-coupled neutral amino acid transporter 1) was preferentially upregulated in the BAT of both genetic and acquired obesity mice in vivo. Moreover, the expression of Slc38a1 was induced by hypoxic stress through hypoxia-inducible factor-1α, which is a master transcription factor of the adaptive response to hypoxic stress, in brown adipocytes in vitro. These results indicate that Slc38a1 is an obesity-associated gene in BAT and a hypoxia-responsive gene in brown adipocytes.

Some patients experience severe chronic pain after intramedullary spinal cord tumor (IMSCT) resection, but the underlying mechanisms have yet to be fully elucidated. We aimed to investigate perioperative factors associated with chronic pain after IMSCT resection.We analyzed data from a postal survey and the medical records of patients who had undergone IMSCT resection in our institution between 2000 and 2008. Chronic pain was assessed using the Neuropathic Pain Symptom Inventory score, and its associations with factors related to tumor pathology, patient demographics, neurological findings, surgery, anesthesia, and perioperative management were determined.Seventy-eight consecutive patients (55 men and 23 women; age 17 to 79 y) were included in the statistical analysis of the present study. In univariate analyses, sex, body mass index, preoperative tumor-related pain, preoperative nonsteroidal anti-inflammatory drugs, intraoperative hypotension, postoperative corticosteroids, and decrease in Japanese Orthopaedic Association (JOA) scores were found to be associated with postsurgical chronic central pain. Logistic regression analysis identified 3 significant factors: a decline in JOA scores compared with preoperative values (odds ratio [OR], 3.33; 95% confidence interval [CI], 1.18-9.42; P=0.023), intraoperative hypotension (OR, 3.01; 95% CI, 1.02-8.97; P=0.047), and postoperative corticosteroids (OR, 3.21; 95% CI, 1.02-10.09; P=0.046).Decline in JOA score, intraoperative hypotension, and postoperative corticosteroids are independently associated with postsurgical chronic central pain. Intraoperative hypotension and the use of postoperative corticosteroids can be avoided or modified during perioperative management. As results from animal studies have indicated that the administration of corticosteroids may intensify chronic pain, further studies in larger cohorts are required to definitively determine the effect of corticosteroids on postsurgical central pain.