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A 79-year-old man with smoldering multiple myeloma (MM) developed sudden severe thrombocytopenia and active bleeding. Since anti-GPIIb/IIIa autoantibodies were detected on the platelet surface, thrombocytopenia due to an autoimmune etiology was diagnosed. Although neither steroids nor intravenous immunoglobulins provided improvement, bortezomib provided rapid normalization of the platelet counts with disappearance of the anti-GPIIb/IIIb autoantibodies. MM is rarely associated with immune thrombocytopenic purpura (ITP). Although the underlying pathogenesis of MM and ITP remains elusive, anti-myeloma drugs might be beneficial.

Introduction: Spatial orientation refers to the perception of relative location and self-motion in space. The accurate formation of spatial orientation is essential for animals to survive and interact safely with their environment. The formation of spatial orientation involves the integration of sensory inputs from the vestibular, visual, and proprioceptive systems. Vestibular organs function as specialized head motion sensors, providing information regarding angular velocity and linear acceleration via the semicircular canals and otoliths, respectively. However, because forces arising from the linear acceleration (translation) and inclination relative to the gravitational axis (tilt) are equivalent, they are indistinguishable by accelerometers, including otoliths. This is commonly referred to as the tilt - translation ambiguity, which can occasionally lead to the misinterpretation of translation as a tilt. The major theoretical frameworks addressing this issue have proposed that the interpretation of tilt versus translation may be contingent on an animal's previous experiences of motion. However, empirical confirmation of this hypothesis is lacking., Methods: In this study, we conducted a behavioral experiment using goldfish to investigate how an animal's motion experience influences its interpretation of tilt vs. translation. We examined a reflexive eye movement called the vestibulo-ocular reflex (VOR), which compensatory-rotates the eyes in response to head motion and is known to reflect an animal's three-dimensional head motion estimate., Results: We demonstrated that the VORs of naïve goldfish do not differentiate between translation and tilt at 0.5 Hz. However, following prolonged visual-translation training, which provided appropriate visual stimulation in conjunction with translational head motion, the VORs were capable of distinguishing between the two types of head motion within 3 h. These results were replicated using the Kalman filter model of spatial orientation, which incorporated the variable variance of process noise corresponding to the accumulated motion experience., Discussion: Based on these experimental and computational findings, we discuss the neural mechanism underlying the resolution of tilt-translation ambiguity within a context analogous to, yet distinct from, previous cross-axis VOR adaptations., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Tadokoro, Shinji, Yamanaka and Hirata.)

Trigeminal neuralgia presents significant challenges in management, often requiring alternative pharmacotherapy due to resistance or side effects to first-line medications like carbamazepine. This case series investigates the efficacy and safety of mirogabalin, a novel α2δ ligand, in six trigeminal neuralgia patients. Mirogabalin demonstrated varying degrees of pain reduction, with an average Numerical Rating Scale improvement rate of 43.1%. Side effects were generally mild, with drowsiness and dizziness being the most common. Despite limited efficacy in some cases, mirogabalin shows promise as a potential treatment option for trigeminal neuralgia, warranting further investigation. Key words: Trigeminal neuralgia, mirogabalin, α2δ lig., Competing Interests: The authors affirm that there are no apparent conflicting financial interests or personal relationships that could have potentially influenced the findings presented in this paper., (Copyright: © 2024 Medicina Oral S.L.)

Various neuropathies of the cranil nerves can accompany trigeminal neuropathic pain attributed to space-occupying lesions. In this case report, the patient presented with persistent intraoral pain and numbness on the right side of the face. Cranial nerve examination revealed dysfunctional eye movements, diplopia, and mechanical hyposensitivity in the mandibular region. The patient was diagnosed with neuropathy due to intracranial lesions and referred to the Department of Neurosurgery and Otorhinolaryngology. The patient was suspected of having malignant lymphoma and is currently undergoing neurosurgical intervention. This article discusses the importance of the examination of the cranial nerve for patients with persistent pain in the trigeminal nerve distribution.

This paper proposes a novel concept of "stereohaptic vibration," which employs distributed vibration to localize vibration sources outside the body. Inspired by amplitude panning, a stereophonic sound display technique, we developed a method to localize a virtual vibration source (VVS) by polarizing the perceived intensity of multiple vibration stimuli to a specific orientation. Considering the perceptual characteristics of high-frequency vibration, the perceived intensity of the VVS was allocated to multiple vibrators according to the distance and direction of the target. The velocity discrimination performance was confirmed by utilizing four stimuli around the arm and one vibration stimulus to the palm to localize the movement of a VVS throughout the arm. Discrimination experiments of the trajectory of outgoing objects with a single arm and dual arms revealed that our approach could localize in three dimensions, even outside the body. The proposed technology for localizing external virtual vibration sources is expected to enhance the virtual reality experience.

This study aims to represent fine texture differences in pencil hardness using intensity segment modulation (ISM), a sensory equivalent conversion method of vibration from high to low frequencies. This method enables the presentation of delicate tactile sensations even with small transducers. We integrated this approach in the world's thinnest ultra-thin PZT-MEMS vibrator with a stylus-type device. The vibration waveforms of four types of pencil hardness were captured under the same conditions, and the differences in the frequency components were confirmed. We compared the fine texture feelings under raw signal, ISM, and ISM below 1 kHz conditions by conducting discrimination tests and subjective similarity evaluations. The results showed that ISM could reproduce similar feelings of the pencil hardness.

In a fire outbreak, firefighters are expected to rapidly extinguish fires to stop the spread of damage and prevent secondary disasters. We proposed the concept of a dragon firefighter (DFF), which is a flying-hose-type firefighting robot. We developed a 3.6 m long DFF equipped with two nozzle units and achieved stable flight. However, the system was not yet completed because the root of the robot, which should have been operated remotely, was operated manually. In addition, the system's reliability was insufficient to successfully repeat the demonstration several times. The development of a robot demonstration system is crucial for the practical application of such a firefighting robot. In this study, we developed a demonstration system for a remotely controllable 4 m flying firehose robot for demonstration at the World Robot Summit 2020 (WRS 2020) opening ceremony in Fukushima as a milestone. This paper focuses on the following issues: 1): installation of the remotely controllable mobile base, 2): redesign of the water channels (the sizes of nozzle outlets) to get enough thrusts to fly with a fire engine, 3): development of nozzle units with a larger movable range (1.5 times larger than the conventional nozzle) in addition to waterproofing technique to improve system reliability, and 4): redesign of a passive damping mechanism to ensure better stability. Thus, a firefighting demonstration was successfully conducted at the opening ceremony of the World Robot Summit 2020 in Fukushima, Japan, and we discuss the lessons learned through the demonstration. We found that the developed DFF system incorporating a mobile base could achieve remote fire extinguishing., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Yamauchi, Maezawa, Ambe, Konyo, Tadakuma and Tadokoro.)

A high-resolution haptic display that reproduces tactile distribution information on the contact surface between a finger and an object realizes the presentation of the softness of the object and the magnitude and direction of the applied force. In this article, we developed a 32-channel suction haptic display that can reproduce tactile distribution on fingertips with high resolution. The device is wearable, compact, and lightweight, thanks to the absence of actuators on the finger. A FE analysis of the skin deformation confirmed that the suction stimulus interfered less with adjacent stimuli in the skin than when pressing with positive pressure, thus allowing more precise control of local tactile stimuli. The optimal layout with the least error was selected from three configurations dividing 62 suction holes into 32 ports.The suction pressures were determined by calculating the pressure distribution by a real-time finite element simulation of the contact between the elastic object and the rigid finger. A discrimination experiment of softness with different Young's modulus and its JND investigation suggested that the higher resolution of the suction display improved the performance of the softness presentation compared to a 16-channel suction display previously developed by the authors.

Melatonin exerts various physiological effects through melatonin receptors and their ability to scavenge free radicals. Radiotherapy is a common treatment for head and neck tumors, but stomatitis, a side effect affecting irradiated oral mucosa, can impact treatment outcomes. This study investigated the preventive effect of melatonin, a potent free radical scavenger, on radiation-induced oral mucositis. Mice were irradiated with 15 Gy of X-ray radiation to the head and neck, and the oral mucosa was histologically compared between a melatonin-administered group and a control group. The results showed that radiation-induced oral mucositis was suppressed in mice administered melatonin before and after irradiation. It was suggested that the mechanism involved the inhibition of apoptosis and the inhibition of DNA damage. From these findings, we confirmed that melatonin has a protective effect against radiation-induced oral mucositis .

Dental pulp stem cells (DPSCs) are considered a valuable cell source for regenerative medicine because of their high proliferative potential, multipotency, and availability. We established a new cryopreservation method (NCM) for collecting DPSCs, in which the tissue itself is cryopreserved and DPSCs are collected after thawing. We improved the NCM and developed a new method for collecting and preserving DPSCs more efficiently. Dental pulp tissue was collected from an extracted tooth, divided into two pieces, sandwiched from above and below using cell culture inserts, and cultured. As a result, the cells in the pulp tissue migrated vertically over time and localized near the upper and lower membranes over 2-3 days. With regard to the underlying molecular mechanism, SDF1 was predominantly involved in cell migration. This improved method is valuable and enables the more efficient collection and reliable preservation of DPSCs. It has the potential to procure a large number of DPSCs stably.

This study aimed to determine whether the positional relationship between the underside of the screw head and the surface of the alveolar bone could alter the stress on the two surfaces and affect the stability of implanted anchor screws. First, in order to confirm the extent of the gap between the mini-screw and the bone surface, a mini-screw was placed in the palate of rabbits and examined histologically. As a result, in the conventional screw implantation procedure, oral mucosa between the base of the screw head and the bone creates a spatial gap. Removal of the oral mucosa eliminates this gap. Then, we compared the positional difference of the screw in a contact and gap group by analyzing stress distribution on the bone and screw. Analysis using the finite element method showed that more stress was loaded on both the bone and screw in the gap group than in the contact group. Cortical bone thickness did not affect stress in either group. The effects of different load strengths were similar between groups. A surgical procedure in which mucosal coverings are removed so that implanted anchor mini-screws are in contact with the bone surface was found to reduce the stress load on both the bone and screw. This procedure can be used to prevent undesirable dislodgement of implanted mini-screws.

Painful post-traumatic trigeminal neuropathy (PTTN) is a known complication of dental implant therapy. Patients with PTTN develop sensory abnormalities in the orofacial region, which may be a psychosocial aspect, and dentists should assess somatosensory testing and psychosocial factors. The patients were assessed using quantitative sensory testing (QST). A 64-year-old female presented with allodynia of the left lower lip that occurred after a surgical implant procedure. Persistent pain started 4 months after the placement of two dental implants in the mandible. Sensory testing of these areas revealed warm hyposensitivity and mechanical hypersensitivity of the mandibular region. We also assessed PTTN-related perceived injustice using the Injustice Experience Questionnaire. The patient refused medication therapy such as pregabalin; therefore, autogenic training was adopted as an alternative management strategy. We conclude that for expensive dental procedures, such as implant placement, sufficient consensus should be obtained preoperatively before proceeding with surgery.

Considering that every tissue/organ has the most suitable microenvironment for its functional cells, controlling induced pluripotent stem cell (iPSC) differentiation by culture on frozen sections having a suitable microenvironment is possible. Induced PSCs were cultured on frozen sections of the liver, the brain, the spinal cord, and cover glasses (control) for 9 days. The iPSCs cultured on the sections of the liver resembled hepatocytes, whereas those on sections of the brain and the spinal cord resembled neuronal cells. The percentage of hepatocytic marker-positive cells in the iPSCs cultured on the sections of the liver was statistically higher than that of those in the iPSCs cultured on the sections of the brain and the spinal cord or on cover glasses. In contrast, the iPSCs cultured on the sections of the brain and the spinal cord revealed a high percentage of neural marker-positive cells. Thus, iPSCs can be differentiated into a specific cell lineage in response to specific factors within frozen sections of tissues/organs. Differentiation efficacy of the frozen sections markedly differed between the iPSC clones. Therefore, our induction method could be simple and effective for evaluating the iPSC quality.

Dopamine supersensitivity psychosis (DSP) in patients with schizophrenia is induced by treatment with a high dosage of antipsychotics for a long time period, and it is characterized by unstable psychotic symptoms. The upregulation of dopamine D2 receptor (DRD2) provoked by antipsychotics underlies DSP. Aripiprazole does not cause an excessive blockade of DRD2 and is less likely to upregulate DRD2 by aripiprazole's dopamine partial agonistic profile. Aripiprazole; however, has a potential risk of inducing severe rebound psychosis in patients who have already developed dopamine supersensitivity. Recently, an animal model study suggested that aripiprazole could attenuate established dopamine supersensitivity. The present study was conducted to examine whether very slowly switching to aripiprazole could help patients with schizophrenia with dopamine supersensitivity while avoiding rebound psychosis. This study was a single-armed and open-labeled study in which patients were observed over a period of 2 years. Only 11 patients were ultimately recruited. Five patients were successfully switched to a sufficient dose of aripiprazole and completed the study protocol. These five patients did not present with severe DSP over the study period, but only one patient showed a large improvement in psychopathology. Five patients dropped out of the study, and one of these five showed a severe worsening of psychosis. The present study indicated that the introduction of aripiprazole in patients with DSP was difficult, but suggested that aripiprazole could contribute to attaining a stable state in psychosis if it was applied with careful observation.

In the present study, we attempted to characterize two characteristic features within the dynamic behavior of wideband electrocorticography data, which were recorded as the brain waves of epilepsy, comprising high-frequency oscillations (HFOs) and interictal epileptic slow (red slow). The results of power spectrum and nonlinear time series analysis indicate that, on one hand, HFOs at epileptic focus are characterized by one-dimensional dynamical systems in ictal onset time segments at an epileptic focus for two patients' datasets; on the other hand, an interictal epileptic slow is characterized by the residue of power spectrum. The results suggest that the degree of freedom of the brain dynamics during epileptic seizure with HFO degenerates to low-dimensional dynamics; hence, the interictal epileptic slow as the precursors of the seizure onset can be detected simply from interictal brain wave data for the dataset of one patient. Therefore, our results are essential to understand the brain dynamics in epilepsy., Competing Interests: Declaration of Competing Interest Masao Matsuhashi and Akio Ikeda: Department of Epilepsy, Movement Disorders and Physiology, Kyoto University is the Industry-Academia Collaboration Courses, supported by Eisai Co., Ltd., Nihon Kohden Corporation, Otsuka Pharmaceutical Co., Ltd. and UCB Japan Co. Ltd., (Copyright © 2019 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.)

Fast playback allows quick video exploration, but it also decreases the saliency of short events. We propose a haptic exploration for detection of short events during fast video playback, considering that event-related information in vibrotactile feedback can be preserved during fast playback using Time Scale Modification (TSM) methods developed for audio. We evaluate our proposal in two collision detection experiments using first-person view (FPV) videos. In the first experiment, viewers watched at a fixed playback speed, i.e., 1× or 2×, videos recorded with a camera mounted on a platform cart. In this experiment, event-related vibrations were measured at the back of the camera. In the second experiment, viewers used a media controller to adjust the playback speed in videos simulating an exploration with a mobile robot. In this experiment, event-related vibrations were generated from the measurements used in the first experiment. We show that a haptic exploration improves collision awareness under either constant or adjustable playback speed. In both experiments, the number of collisions reported without vibrotactile feedback deviated the greatest from the actual number of collisions in a video. Moreover, collision detection performance with vibrations time-scaled without Time Scale Modification (TSM) methods was not significantly different from performance without vibrations.

Plasma ghrelin level is influenced by Helicobacter pylori ( H. pylori ) status and the severity of gastric mucosal atrophy, and the ghrelin level is associated with nutrition status in hemodialysis patients. Here, we investigated the efficacy of H. pylori eradication therapy in improving nutrition status in relation to the ghrelin level in H. pylori -positive hemodialysis patients. Of H. pylori -positive patients receiving hemodialysis at 8 dialysis center, 21 patients underwent gastroduodenoscopy for evaluation of the severity of gastric atrophy, and nutrition markers and plasma ghrelin levels before and 1 year after H. pylori eradication therapy were evaluated. Serum cholinesterase level was significantly increased after H. pylori eradication compared with the level before eradication (303.2 ± 76.0 vs 287.3 ± 68.1 IU/L, p  = 0.029). In particular, cholesterol (before, 196.6 ± 23.2 mg/dl; after, 206.1 ± 25.9 mg/dl, p  = 0.042) and cholinesterase levels (before, 296.9 ± 70.8 IU/L; after, 316.4 ± 73.8 IU/L, p  = 0.049) increased more strongly in patients with mild-moderate atrophy than those with severe atrophy, irrespective of improvement of plasma acyl-ghrelin and desacyl-ghrelin levels after eradication therapy. In conclusion, H. pylori eradication may improve nutrition status by increasing serum cholinesterase and cholesterol levels in hemodialysis patients, especially those with mild and moderate gastric mucosal atrophy., Competing Interests: No potential conflicts of interest were disclosed.

The kinematic serial chain configuration of a finger modulates the frictional properties during tactile exploration tasks. This paper analyzes and subsequently models the effects of the entire finger during sliding operations on a surface. Qualitative and quantitative study of finger movement patterns with postures, sliding directions, and contact angles first indicate the effect of finger stiffness on contact mechanics. A "stiffness ellipse" is subsequently modeled to incorporate finger pose effects, and then coupled with the lumped mass-spring-damper model of the finger pad to estimate resultant contact forces. The performance of the proposed model is verified by comparing with experimental results obtained from ten subjects. The proposed model could estimate the general tendencies of contact forces with change in postures (Extended and Flexed), sliding directions (proximal and distal), and contact angles (20°, 40° and 60°). The experimental results indicate that finger stiffness significantly modulates the contact forces, stick-slip frequency, preloading duration and initial spike during sliding. Introduction of finger posture effects could explain the change in finger normal force during tactile exploration tasks. The proposed haptic rendering model can be used to give a more natural user feedback in virtual fingertip-surface interactions.

Gout is a multifactorial disease characterized by acute inflammatory arthritis, and it is caused as a consequence of hyperuricemia. A recent meta-analysis of genome-wide association studies has newly identified the relationship between serum uric acid (SUA) levels and rs889472, a single nucleotide polymorphism of musculoaponeurotic fibrosarcoma oncogene (MAF/c-MAF). However, it remained unclear whether rs889472 is associated with gout susceptibility. In the present study, we investigate the association between c-MAF rs889472 and gout in Japanese male population. We genotyped 625 male patients who were clinically diagnosed as gout and 1221 male control subjects without hyperuricemia or a history of gout by TaqMan method. As a result, the major allele (C), which reportedly increases SUA levels, had a higher frequency in the gout cases (58.8%) than in the controls (55.0%). A logistic regression analysis showed a significant association between rs889472 and gout (p = 0.029, odds ratio = 1.17; 95% confidence interval 1.02-1.34). C-MAF is reported as a pivotal transcriptional factor in the development and differentiation of renal proximal tubular cells. Because urate is mainly regulated in renal proximal tubular cells, c-MAF may have an important role in urate regulation in the kidney and influence not only SUA but also gout susceptibility. Our finding shows that rs889472 of c-MAF is associated with gout susceptibility.

Cationic liposomes are commonly used as vectors to effectively introduce foreign genes (antisense DNA, plasmid DNA, siRNA, etc.) into target cells. Cationic liposomes are also known to affect cellular immunocompetences such as the mast cell function in allergic reactions. In particular, we previously showed that the cationic liposomes bound to the mast cell surface suppress the degranulation induced by cross-linking of high affinity IgE receptors in a time- and dose-dependent manner. This suppression is mediated by impairment of the sustained level of intracellular Ca 2+ concentration ([Ca 2+ ] i ) via inhibition of store-operated Ca 2+ entry (SOCE). Here we study the mechanism underlying an impaired [Ca 2+ ] i increase by cationic liposomes in mast cells. We show that cationic liposomes inhibit the phosphorylation of Akt and PI3 kinases but not Syk and LAT. As a consequence, SOCE is suppressed but Ca 2+ release from endoplasmic reticulum (ER) is not. Cationic liposomes inhibit the formation of STIM1 puncta, which is essential to SOCE by interacting with Orai1 following the Ca 2+ concentration decrease in the ER. These data suggest that cationic liposomes suppress SOCE by inhibiting the phosphorylation of PI3 and Akt kinases in mast cells., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Dopamine supersensitivity psychosis (DSP) is a type of acute exacerbation of recurrent psychosis caused by long-term treatment with antipsychotics in schizophrenic patients. Although DSP is exceedingly troublesome for clinicians, effective treatment has not yet been established. Based on clinical research and our animal study, we hypothesize that aripiprazole, an atypical antipsychotic, may reduce the exacerbation of recurrent psychotic episodes. We report the case of a 46-year-old female who suffered from schizophrenia with DSP. In this case, sustained treatment with a high dose of aripiprazole gradually reduced the　 severity of her recurrent psychotic episodes. In conclusion, sustained treatment with aripiprazole may reduce the exacerbation of recurrent psychotic episodes in schizophrenic patients with DSP, and may be an effective treatment of DSP.

Previous finite element analyses of peri-implant stress assumed a bone-implant contact (BIC) ratio of 100%, even though the BIC ratio is known to be approximately 50% or less. However, the recent development of ultraviolet treatment of titanium immediately before use, known as photofunctionalization, significantly increased the BIC ratio, to 98.2%. We used a unique finite element analysis model that enabled us to examine the effects of different BIC ratios on peri-implant stress. A three-dimensional model was constructed under conditions of vertical or oblique loading, an implant diameter of 3.3, 3.75, or 5.0 mm, and a BIC ratio of 53.0% or 98.2%. Photofunctionalization and larger implant diameters were associated with reduced stress on surrounding tissues. Under vertical loading, photofunctionalization had a greater effect than increased implant diameter on stress reduction. Under oblique loading, increased implant diameter had a greater effect than photofunctionalization on stress reduction.

Optimal management of patients with chronic myeloid leukemia in chronic phase with suboptimal molecular response (MR) to frontline imatinib is undefined. We report final results from SENSOR, which evaluated efficacy/safety of nilotinib in this setting. A substudy assessed whether BIM polymorphisms impacted response to nilotinib. In this single-arm, multicenter study, Japanese patients with suboptimal MR per European LeukemiaNet 2009 criteria (complete cytogenetic response, but not major MR [MMR]) after ≥18 months of frontline imatinib received nilotinib 400mg twice daily for 24 months. MR, BCR-ABL1 mutations/variants, and BIM polymorphisms were evaluated in a central laboratory. Primary endpoint was the MMR rate at 12 months (null hypothesis of 40%). Of 45 patients (median exposure, 22.08 months), 39 completed the study and six discontinued. At 12 and 24 months, 51.1% (95% CI, 35.8%-66.3%) and 66.7% (95% CI, 51.0%-80.0%) achieved MMR, respectively. Cumulative MMR incidence by 24 months was 75.6%. Of 40 patients analyzed, 10 of 12 (83.3%) with and 17 of 28 (60.7%) without BIM polymorphisms achieved MMR at 24 months. The safety profile was manageable with dose reductions and interruptions. Nilotinib provided clinical benefit for patients with suboptimal response to imatinib, and BIM polymorphisms did not influence MMR achievement. ClinicalTrials.gov: NCT01043874., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Objective: Ototoxic damage caused by aminoglycosides (AG) leads to the loss of cochlear hair cells (HCs). In mammals, mature cochlear HCs are unable to regenerate, and their loss results in permanent hearing deficits. Our objective was to protect the inner ear from damage after an AG challenge. The generation of reactive oxygen species (ROS), one of the earliest events in the process of AG ototoxicity, is considered to play a key role in the initiation of HC death. We examined whether Hangesha-shin-to (TJ-014), a traditional Japanese Kampo medicine considered to be a potent antioxidant, protects HCs from gentamicin (GM)-induced damage., Methods: Organ of Corti explants removed from postnatal day 3-5 rats were maintained in tissue culture and exposed to 50μM GM for up to 48h. The effects of TJ-014 on GM-induced ototoxicity were assessed by HC counts and immunohistochemistry against cleaved caspase-3, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and a probe reacting to mitochondrial function changes., Results: TJ-014 treatments significantly reduced GM-induced HC loss and immunoreactivities for cleaved caspase-3 and 8-OHdG; these effects were correlated with increasing TJ-014 concentrations. Moreover, TJ-014 protected the mitochondrial membrane potential from GM ototoxicity., Conclusion: These findings indicate the potential of TJ-014 to prevent GM-induced cochlear damage involving ROS., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Recent studies have revealed that soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins interact with each other, forming a SNARE complex that induces exocytosis in mast cells. Previously, we reported that syntaxin-3, a SNARE protein, regulates mast cell exocytosis and is constantly phosphorylated. In this study, we tried to identify the amino acid residue that is phosphorylated in mast cells, and to elucidate the regulatory mechanism of exocytosis by phosphorylation in syntaxin-3. We found that Thr 14 of syntaxin-3 was a phosphorylation site in mast cells. In addition, the overexpression of a constitutively dephosphorylated syntaxin-3 (T14A) mutant enhanced mast cell exocytosis. We also showed that the phosphomimetic mutation of syntaxin-3 at Thr 14 (T14E) induced structural changes in syntaxin-3, and this mutation inhibited binding of syntaxin-3 to Munc18-2. These results suggest that phosphorylated syntaxin-3 at Thr 14 negatively regulates mast cell exocytosis by impairing the interaction between syntaxin-3 and Munc18-2., (© 2016 International Federation for Cell Biology.)

We examined the effects of polyoxyethylene alkyl ethers (Brijs) on the intestinal transport and absorption of rhodamine 123, a P-glycoprotein (P-gp) substrate, by in vitro and in vivo studies. Brijs increased the absorptive transport of rhodamine 123 and decreased its secretory transport in the in vitro diffusion chamber method. However, Brijs did not change the transport of 5(6)-carboxyfluorescein, a non-P-gp substrate, indicating that the effect of Brijs on the transport of drugs was P-gp substrate-specific. The effects of Brijs on rhodamine 123 transport across Caco-2 cell monolayers were also examined. Secretory transport of rhodamine 123 was enhanced and its absorptive transport was significantly reduced in the presence of Brijs. Furthermore, in the in vivo studies, Brijs also enhanced the intestinal absorption of rhodamine 123 in rats. The intestinal membrane damage produced by Brijs was also evaluated by measuring the activity of lactate dehydrogenase and the release of protein. We found almost no intestinal damage in the presence of various Brijs. These findings suggest that Brijs might inhibit the function of intestinal P-gp, thereby increasing the intestinal transport and absorption of P-gp substrates without serious intestinal membrane damage., (Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.)

Mast cells are involved in allergic responses and undergo exocytotic release of inflammatory mediators in response to antigen stimulation. Soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins are involved in this membrane fusion process; some SNARE-binding proteins regulate SNARE-dependent liposome membrane fusion. SNARE-binding protein complexin II is expressed in mast cells, where it positively regulates exocytotic release after antigen stimulation. We found that complexin II suppressed SNARE-dependent membrane fusion between mast cell SNARE-containing liposomes. This inhibitory effect of complexin II was abolished when we used a structurally divergent mutant (R59H) complexin II, where Arg59 is substituted with histidine. These results suggest that complexin II negatively regulates SNARE-dependent exocytotic membrane fusion in mast cells, and this inhibitory effect is dependent upon Arg59.

In humans, long-term antipsychotic treatment is known to induce movement disorders and a psychosis, called dopamine supersensitivity psychosis (DSP). The mechanism by which chronic administration of antipsychotic(s) causes DSP may be the treatment-induced up-regulation of dopamine D2 receptors (DRD2). G protein-coupled receptor kinase 6 (GRK6) and beta-arrestin 2 (ARRB2) play important roles in the trafficking of DRD2 by phosphorylation and internalization. We investigated the effects of chronic continuous treatment with mini-pump-administered haloperidol (HAL) on the sensitivity of Wistar rats to dopamine, as measured by the locomotor response to methamphetamine (MAP) and the density of striatal DRD2. Chronic continuous treatment with HAL resulted in significantly higher locomotor response to MAP and significantly higher striatal DRD2 density compared with those in rats administered vehicle (VEH). Enzyme-linked immunosorbent assays revealed that striatal ARRB2 in DSP model rats tended to decrease in comparison with that in the VEH group. In addition, the ratio of GRK6/ARRB2 in DSP model rats was significantly higher than that in controls. Our results suggest that alterations of the GRK6 and ARRB2 system could induce both DRD2 up-regulation and impairment of the dopamine signaling pathway, resulting potentially in the development of DSP., (© The Author(s) 2015.)

The rare central nervous system (CNS) infiltration of Waldenström macroglobulinemia (WM) is known as Bing-Neel syndrome (BNS). Furthermore, the transformation of WM into diffuse large B-cell lymphoma (DLBCL) is also unusual. Herein, we report a 69-year-old male with DLBCL transformed from BNS. In November 2008, the patient visited a prior hospital because of anemia and was diagnosed with WM. After receiving chemotherapy (R-CHOP), his serum immunoglobulin M (IgM) level decreased and then remained at approximately 2000 mg/dl for 3 years. In November 2011, he complained of visual impairment and photophobia in his left eye. Magnetic resonance imaging showed enlargement of the left optic nerve and cerebrospinal fluid examination indicated CNS infiltration of WM cells. Consequently, he was diagnosed with BNS. He thus received CNS targeted chemotherapy (R-MPV) and achieved a partial response. In May 2014, IgM was elevated and swelling of systemic lymph nodes was detected. Inguinal lymph node biopsy yielded a pathological diagnosis of DLBCL and the clonality of tumor cells between WM and DLBCL was confirmed by the allele-specific oligonucleotide polymerase chain reaction (ASO-PCR).

Recent studies have revealed that SNARE proteins are involved in exocytotic release in mast cells. Previously, we reported that mast cell SNARE proteins induce membrane fusion between liposomes. Moreover, we found that synaptotagmin 2, a candidate Ca2+ sensor for mast cell exocytosis, enhanced SNARE-mediated membrane fusion via Ca2+ and phosphatidylserine. Phosphatidylinositol 4,5-bisphosphate (PIP2) is an acidic phospholipid like phosphatidylserine. In the present study, we investigated whether PIP2 is involved in the enhancement effect of synaptotagmin 2 on SNARE-mediated membrane fusion. PIP2 did not show any significant effect on SNARE-mediated membrane fusion by itself. In the presence of Ca2+, synaptotagmin 2 enhanced SNARE-mediated membrane fusion between liposomes containing PIP2. However, even in the presence of Ca2+, when we used 100% PC liposomes, synaptotagmin 2 did not show any significant effect on SNARE-mediated membrane fusion. These results indicated that PIP2 is involved in the enhancement effect of synaptotagmin 2 on membrane fusion between liposomes containing mast cell SNARE proteins., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Quantitative polymerase chain reaction (PCR) with patient-specific, allele-specific oligonucleotide (ASO) primers for individual immunoglobulin H VDJ region (ASO-PCR) amplification was performed using several sources of clinical material, including mRNA from peripheral blood cells (PBMNCs), whole bone marrow cells (BMMNCs), and the CD20+ CD38- B-cell population in bone marrow, as well as cell-free DNA from the sera of patients with multiple myeloma (MM). We designed the ASO primers and produced sufficient PCR fragments to evaluate tumor burden in 20 of 30 bone marrow samples at diagnosis. Polymerase chain reaction amplification efficiency depended on primer sequences because the production of ASO-PCR fragments did not correlate with serum M-protein levels. However, the ASO-PCR levels in BMMNCs showed statistically significant correlations with those in PBMNCs and CD20+ CD38- B-cells. The good association between the BMMNC and PBMNC data indicated that PBMNCs could be a suitable source for monitoring minimal residual disease (MRD). In the case of cell-free DNA, ASO-PCR levels showed a unique pattern and remained high even after treatment. Because the sequence information for each ASO-PCR product was identical to the original, the cell-free DNA might also be useful for evaluating MRD. Moreover, the ASO-PCR products were clearly detected in 17 of 22 mRNA samples from CD20+ CD38- populations, suggesting that MM clones might exist in relatively earlier stages of B cells than in plasma cells. Thus, ASO-PCR analysis using various clinical materials is useful for detecting MRD in MM patients as well as for clarifying MM pathogenesis., (Copyright © 2015 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.)

Introduction: Leptin, a 16 kDa anti-obesity hormone, exhibits various physiological properties. Interestingly, skin wound healing was proven to delay in leptin-deficient ob/ob mice. However, little is known on the mechanisms of this phenomenon. In this study, we attempted to elucidate a role of leptin in wound healing of skin., Methods: Immunohistochemical analysis was performed to confirm the expression of the leptin receptor (Ob-R) in human and mouse skin. Leptin was topically administered to chemical wounds created in mouse back skin along with sustained-release absorbable hydrogel. The process of wound repair was histologically observed and the area of ulceration was measured over time. The effect of leptin on the proliferation, differentiation and migration of human epidermal keratinocytes was investigated., Results: Ob-R was expressed in epidermal cells of human and mouse skin. Topical administration of leptin significantly promoted wound healing. Histological analysis showed more blood vessels in the dermal connective tissues in the leptin-treated group. The proliferation, differentiation/function and migration of human epidermal keratinocytes were enhanced by exogenous leptin., Conclusion: Topically administered leptin was proven to promote wound healing in the skin by accelerating proliferation, differentiation/function and migration of epidermal keratinocytes and enhancing angiogenesis around the wounded area. These results strongly suggest that topical administration of leptin may be useful as a treatment to promote wound healing in the skin.

The increase in intracellular Ca(2+) through the Ca(2+) channel is an indispensable step for the secretion of inflammatory mediators by mast cells. It was recently reported that Orai-1 is responsible for the Ca(2+) influx that is activated by depletion of stored Ca(2+). There are three isoforms of Orai: Orai-1, Orai-2, and Orai-3; however, isoforms other than Orai-1 are poorly understood. We found that Orai-2 is expressed and localized on secretory granules in RBL-2H3. Ca(2+) release from Ca(2+) store, induced by antigen stimulation, was significantly attenuated by knockdown of Orai-2, while that induced by thapsigargin was not affected. Furthermore, exocytotic release induced by antigen stimulation was inhibited in knockdown cells. This observation suggests a new role of Orai isoforms in secretory cells., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Introduction: Leptin, a 16 kDa circulating anti-obesity hormone, exhibits many physiological properties. Recently, leptin was isolated from saliva; however, its function in the oral cavity is still unclear. In this study, we investigated the physiological role of leptin in the oral cavity by focusing on its effect on wound healing in the oral mucosa., Methods: Immunohistochemical analysis was used to examine the expression of the leptin receptor (Ob-R) in human/rabbit oral mucosa. To investigate the effect of leptin on wound healing in the oral mucosa, chemical wounds were created in rabbit oral mucosa, and leptin was topically administered to the wound. The process of wound repair was histologically observed and quantitatively analyzed by measuring the area of ulceration and the duration required for complete healing. The effect of leptin on the proliferation, differentiation and migration of human oral mucosal epithelial cells (RT7 cells) was investigated using crystal violet staining, reverse transcription polymerase chain reaction (RT-PCR) and a wound healing assay, respectively., Results: Ob-R was expressed in spinous/granular cells in the epithelial tissue and vascular endothelial cells in the subepithelial connective tissue of the oral mucosa. Topical administration of leptin significantly promoted wound healing and shortened the duration required for complete healing. Histological analysis of gingival tissue beneath the ulceration showed a denser distribution of blood vessels in the leptin-treated group. Although the proliferation and differentiation of RT7 cells were not affected by leptin, the migration of these cells was accelerated in the presence of leptin., Conclusion: Topically administered leptin was shown to promote wound healing in the oral mucosa by accelerating epithelial cell migration and enhancing angiogenesis around the wounded area. These results strongly suggest that topical administration of leptin may be useful as a treatment to promote wound healing in the oral mucosa.

Integrin-linked kinase (ILK) is an important signaling regulator that assembles into the heteroternary complex with adaptor proteins PINCH and parvin (termed the IPP complex). We recently reported that ILK is important for integrin activation in a Chinese hamster ovary (CHO) cell system. We previously established parental CHO cells expressing a constitutively active chimeric integrin (αIIbα6Bβ3) and mutant CHO cells expressing inactive αIIbα6Bβ3 due to ILK deficiency. In this study, we further investigated the underlying mechanisms for ILK-dependent integrin activation. ILK-deficient mutant cells had trace levels of PINCH and α-parvin, and transfection of ILK cDNA into the mutant cells increased not only ILK but also PINCH and α-parvin, resulting in the restoration of αIIbα6Bβ3 activation. In the parental cells expressing active αIIbα6Bβ3, ILK, PINCH, and α-parvin were co-immunoprecipitated, indicating the formation of the IPP complex. Moreover, short interfering RNA (siRNA) experiments targeting PINCH-1 or both α- and β-parvin mRNA in the parent cells impaired the αIIbα6Bβ3 activation as well as the expression of the other components of the IPP complex. In addition, ILK mutants possessing defects in either PINCH or parvin binding failed to restore αIIbα6Bβ3 activation in the mutant cells. Kindlin-2 siRNA in the parental cells impaired αIIbα6Bβ3 activation without disturbing the expression of ILK. For CHO cells stably expressing wild-type αIIbβ3 that is an inactive form, overexpression of a talin head domain (THD) induced αIIbβ3 activation and the THD-induced αIIbβ3 activation was impaired by ILK siRNA through a significant reduction in the expression of the IPP complex. In contrast, overexpression of all IPP components in the αIIbβ3-expressing CHO cells further augmented THD-induced αIIbβ3 activation, whereas they did not induce αIIbβ3 activation without THD. These data suggest that the IPP complex rather than ILK plays an important role and supports integrin activation probably through stabilization of the active conformation.

Several studies have shown that cationic liposomes exert immunomodulatory effects with low immunogenicity and toxicity, and offer advantages such as easy preparation and targeting. Cationic liposomes not only transport DNA to immune cells but also enhance the function of antigen presenting cells such as dendritic cells and macrophages. Here, we investigated the effect of a particular cationic liposome on mast cell function during allergic reaction. We found that the cationic liposomes bound to the mast cell surface suppressed degranulation induced by cross-linking of high affinity immunoglobulin E receptors in a time- and dose-dependent manner. The suppression of degranulation was mediated by impairment of the sustained level of intracellular Ca(2+) concentration ([Ca(2+)]i) derived from the inhibition of store-operated Ca(2+) entry. The decrease in sustained elevation of [Ca(2+)]i led to the suppression of phosphorylation of soluble N-ethylmaleimide-sensitive factor attachment protein receptor proteins such as SNAP-23, syntaxin-4, which are necessary for membrane fusion between secretory granules and the plasma membrane during degranulation. Furthermore, the cationic liposomes suppressed vascular permeability elevation induced by mast cell activation in mice. These results showed that cationic liposomes possess the novel property of inhibiting mast cell activation, suggesting the possibility of developing cationic liposomes as anti-allergic effectors., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Several studies have proposed an optimal dopamine D2 receptor occupancy by antipsychotics (OOc) to establish optimal pharmacological treatment of schizophrenia. However, there are limitations to the use of the OOc, especially in application to patients with treatment-resistant schizophrenia, including dopamine supersensitivity psychosis (DSP) or late-onset psychosis (LOP). It has been suggested that D2 receptor density is up-regulated by chronic treatment of antipsychotics in DSP, whereas it may be low in LOP owing to age-related reduction. In estimation of the proposed OOc, these alterations have not been taken into account, which may be one of the factors contributing to the limited application of this index. We here hypothesize that there is an optimal range in the number of D2 receptors available for dopamine binding to elicit adequate neurotransmission in the treatment of patients with schizophrenia. We then estimated the OOc under the assumption that the range is constant while D2 density is variable. The results showed that the OOc and plasma level of antipsychotics increase with an increase in the D2 density but decrease with a decrease in the D2 density. That is, if the range of OOc is 65% to 78% in a standard D2 density, it becomes 82% to 89% under 2-fold up-regulated density and 42% to 63% under a 40% reduced density. The results also indicated that the reduction of the plasma antipsychotic level is greater during a given time period in patients with higher D2 density, as they need a higher antipsychotic dose to achieve the raised OOc, which would account for the clinical features of DSP, for example, acute exacerbation after a discontinuation of antipsychotics. On the other hand, in patients with lower D2 density, only a lower antipsychotic dose will achieve the OOc, and a small increase in the dose will result in a greater increase in occupancy and induce extrapyramidal adverse effects more easily. Furthermore, the reduction of the plasma antipsychotic level during the time period is smaller, which prolongs extrapyramidal adverse effects after discontinuation of antipsychotics in LOP. We also attempted to develop a strategy for the prevention and treatment of patients with DSP or LOP by focusing on D2 density.

Aripiprazole (ARI) is one of atypical antipsychotics used for the treatment of schizophrenia all over the world, owing to its tolerability and ability to keep antipsychotic effect for an extended period of time. Its unique pharmacological feature, which is known as dopamine partial agonist, enables clinically relevant dopamine(2) receptor blockade and prevents extrapyramidal adverse effects. On the basis of our preclinical experiments and clinical case study, we discovered that ARI had an ability to stabilize the sensitivity to dopamine. Excessive sensitivity to dopamine is hypothesized to lead to exacerbation or relapse of psychotic symptoms. Therefore, we speculate that ARI can prevent schizophrenic patients from exacerbation or relapse of psychotic symptoms by reducing excessive sensitivity to dopamine.

Platelet integrin α(IIb)β(3) activation is regulated by inside-out signaling via agonist stimulation. However, when α(IIb)β(3) was exogenously expressed in cell lines such as Chinese hamster ovarian cells, physiological agonists hardly induced α(IIb)β(3) activation. To overcome this disadvantage, we characterized the functional regulation of endogenously expressed α(IIb)β(3) in a megakaryoblastic cell line, CMK, employing an initial velocity assay for PAC-1 binding. We firstly demonstrated that protease-activated receptor 1-activating peptide induced robust, but transient α(IIb)β(3) activation in CMK cells with high glycoprotein-Ib expression. Stable talin-1 or kindlin-3 knockdown cells confirmed that the protease-activated receptor 1-activating peptide-induced α(IIb)β(3) activation was dependent on talin-1 and kindlin-3 expression. In sharp contrast to exogenously expressed α(IIb)β(3) in Chinese hamster ovarian cells, transient overexpression of full-length talin (FL-talin) or talin-head domain (THD) alone did not activate α(IIb)β(3) in CMK cells, but required agonist stimulation. Similarly, kindlin-3 overexpression alone did not induce α(IIb)β(3) activation, but it significantly augmented agonist-induced α(IIb)β(3) activation. Several mutants of FL-talin and THD suggested that the head-rod interaction was critical for autoinhibition of talin-1, and the interaction between the THD and the membrane-proximal region of the β(3) cytoplasmic tail was essential for talin-mediated α(IIb)β(3) activation. In addition, THD and kindlin-3 cooperatively augmented protease-activated receptor 1-induced α(IIb)β(3) activation. We proposed that the CMK cell line is an attractive platform for investigating agonist-, talin-1-, and kindlin-3- dependent α(IIb)β(3) activation., (Copyright © 2013 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.)

Anti-apoptotic Bcl-2 family proteins, which inhibit the mitochondrial pathway of apoptosis, are involved in the survival of various hematopoietic lineages and are often dysregulated in hematopoietic malignancies. However, their involvement in the megakaryocytic lineage is not well understood. In the present paper, we describe the crucial anti-apoptotic role of Mcl-1 and Bcl-xL in this lineage at multistages. The megakaryocytic lineage-specific deletion of both, in sharp contrast to only one of them, caused apoptotic loss of mature megakaryocytes in the fetal liver and systemic hemorrhage, leading to embryonic lethality. ABT-737, a Bcl-xL/Bcl-2/Bcl-w inhibitor, only caused thrombocytopenia in adult wild-type mice, but further induced massive mature megakaryocyte apoptosis in the Mcl-1 knockout mice, leading to severe hemorrhagic anemia. All these phenotypes were fully restored if Bak and Bax, downstream apoptosis executioners, were also deficient. In-vitro study revealed that the Jak pathway maintained Mcl-1 and Bcl-xL expression levels, preventing megakaryoblastic cell apoptosis. Similarly, both were involved in reticulated platelet survival, whereas platelet survival was dependent on Bcl-xL due to rapid proteasomal degradation of Mcl-1. In conclusion, Mcl-1 and Bcl-xL regulate the survival of the megakaryocytic lineage, which is critically important for preventing lethal or severe hemorrhage in both developing and adult mice.

Background: Long-term treatment of schizophrenia with antipsychotics is crucial for relapse prevention, but a prolonged blockade of D(2) dopamine receptors may lead to the development of supersensitivity psychosis. We investigated the chronic effects of aripiprazole (ARI) on dopamine sensitivity., Methods: We administered ARI (1.5 mg/kg/d), haloperidol (HAL; 0.75 mg/kg/d), or vehicle (VEH) via minipump for 14 days to drug-naive rats or to rats pretreated with HAL (0.75 mg/kg/d) or VEH via minipump for 14 days. On the seventh day following treatment cessation, we examined the effects of the treatment conditions on the locomotor response to methamphetamine and on striatal D(2) receptor density (N = 4-10/condition/experiment)., Results: Chronic treatment with HAL led to significant increases in locomotor response and D(2) receptor density, compared with the effects of chronic treatment with either VEH or ARI; there were no significant differences in either locomotor response or D(2) density between the VEH- and ARI-treated groups. We also investigated the effects of chronic treatment with HAL, ARI, or VEH preceded by HAL or VEH treatment on locomotor response and D(2) density. ANOVA analysis indicated that the rank ordering of groups for both locomotor response and D(2) density was HAL-HAL > HAL-VEH > HAL-ARI > VEH-VEH., Conclusions: Chronic treatment with ARI prevents development of dopamine supersensitivity and potentially supersensitivity psychosis, suggesting that by reducing excessive sensitivity to dopamine and by stabilizing sensitivity for an extended period of time, ARI may be helpful for some patients with treatment-resistant schizophrenia.

Platelet-associated (PA) IgG autoantibodies play an essential role in primary immune thrombocytopenia (ITP). However, little is known about the epitopes of these Abs. This study aimed to identify critical binding regions for PA anti-αIIbβ3 Abs. Because PA anti-αIIbβ3 Abs bound poorly to mouse αIIbβ3, we created human-mouse chimera constructs. We first examined 76 platelet eluates obtained from patients with primary ITP. Of these, 26 harbored PA anti-αIIbβ3 Abs (34%). Further analysis of 15 patients who provided sufficient materials showed that the epitopes of these Abs were mainly localized in the N-terminal half of the β-propeller domain in αIIb (L1-W235). We could identify 3 main recognition sites in the region; 2 eluates recognized a conformation formed by the W1:1-2 and W2:3-4 loops, 5 recognized W1:2-3, and 4 recognized W3:4-1. The remaining 4 eluates could not be defined by the binding sites. Within these regions, we identified residues critical for binding, including S29 and R32 in W1:1-2; G44 and P45 in W1:2-3; and P135, E136, and R139 in W2:3-4. Of 11 eluates whose recognition sites were identified, 5 clearly showed restricted κ/λ-chain usage. These results suggested that PA anti-αIIbβ3 Abs in primary ITP tended to recognize highly restricted regions of αIIb with clonality.

We had previously developed surface-modified poly (D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) for use as a cellular drug delivery system. The cellular uptake of PLGA-NPs was mediated predominantly by endocytosis, and this uptake was increased by surface modifications with polymers, such as chitosan (CS) and polysorbate 80 (P80). In the present study, we prepared a cell-sized giant unilamellar vesicle (GUV) that mimics a cell membrane to investigate the interaction between cell membranes and NPs. Endocytosis-like uptake of NPs into a GUV was observed when the NPs were modified with nonionic surfactant P80 probably due to change in viscoelasticity and enhanced fusion activity of the membrane induced by P80. In contrast, unmodified NPs and those modified with CS were not internalized into a GUV. These results suggest that surface properties of PLGA-NPs are an important formulation parameter for their interaction with lipid membranes.

It is well established that the plasma membrane exhibits an asymmetric distribution of lipids between the inner and outer leaflets of the lipid bilayer. Recent studies suggest that the asymmetric distribution changes locally and temporarily, accompanied by cellular events. However, available methods to detect lipid asymmetry lack spatio-temporal resolution. As a technique of potential use for real-time imaging of lipid asymmetry, we a novel method that utilizes fluorescence resonance energy transfer (FRET) between NBD-labeled phospholipids (donor) and extracellular rhodamine (acceptor). When cell apoptosis was induced by staurosporine, the fluorescence intensity of NBD-labeled phosphatidylserine decreased owing to FRET from NBD to rhodamine. This method provides a simple way to detect lipid asymmetry and may be useful for observing dynamic changes in asymmetric distribution of lipids., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The objective of this study is to evaluate the effect of polymeric nanoparticles (NPs) on the allergic response of mast cells that release inflammatory mediators such as histamine through exocytosis. Submicron-sized biodegradable poly(DL-lactide-co-glycolide) (PLGA) NPs were prepared by the emulsion solvent diffusion method. Here, we examined the interactions of the mast cells with two types of PLGA NPs, unmodified NPs and NPs modified with chitosan (CS), a biodegradable cationic polymer. The cellular uptake of NPs increased by CS modification due to electrostatic interactions with the plasma membrane. NPs were taken up by mast cells through an endocytic pathway (endocytic phase) and then the cellular uptake was saturated and maintained plateau level by the exclusion of NPs through exocytosis (exocytic phase). Antigen-induced histamine release from mast cells was inhibited during the exocytic phase. The extent of histamine release inhibition was related to the amount of excluded NPs. Exocytic exclusion of NPs competitively antagonize the antigen-induced exocytotic release of histamine by highjacking exocytosis machinery such as SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins, since histamine release was recovered in mast cells that overexpress SNAP-23. The inhibitory effect of the allergic response by PLGA NPs was also evaluated in vivo using the mouse model for systemic anaphylaxis. The administration of NPs suppressed the antigen-induced systemic allergic response in vivo. In conclusion, PLGA NP itself has actions to inhibit the allergic responses mediated by mast cells., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Tactile feedback enhances the usability and enjoyment of human-computer interfaces. Many feedback techniques have been devised to present tactile stimuli corresponding to a user's hand movements taking account of the concept of active touch. However, hand movements may not necessarily be required for achieving natural tactile feedback. Here, we propose a virtual-active-touch method that achieves haptic perception without actual/direct hand movements. In this method, a cursor manipulated by a force-input device is regarded as a virtual finger of the operator on the screen. Tactile feedback is provided to the operator in accordance with cursor movements. To validate the translation of virtual roughness gratings, we compare the virtual-active-touch interface with an interface that involves actual hand movements. By using the appropriate force-to-velocity gain for the pointing-stick interface, we show that the virtual-active-touch method presents the surface wavelengths of the gratings, which is a fundamental property for texture roughness, and that the gain significantly influences the textures experienced by the operators. Furthermore, we find that the perceived wavelengths of objects scaled and viewed on a small screen are skewed. We conclude that although some unique problems remain to be solved, we may be able to perceive the surface wavelengths solely with the intentions of active touch through virtual-active-touch interfaces.

Background: Biosurfactant mannosyl-erythritol lipids (MELs) are glycolipids produced by microbes that have various biological activities. It has been reported that MELs exhibit excellent surface-activity and also various bioactivities, such as induction of cell differentiation and apoptosis. However, little is known about their action related to drug discovery or drug seeds., Methods: We investigated the effects of MELs on the secretion of inflammatory mediators from mast cells that play a central role in allergic responses. Mast cells secrete three kinds of inflammatory mediators and we quantified these secreted mediators by photometer or ELISA. The action mechanisms of MELs were studied by Ca(2+)-sensitive fluorescence dye and Western blotting of phosphorylated proteins., Results: MELs inhibited exocytotic release by antigen stimulation in a dose-dependent manner. We also found that MELs inhibited antigen-induced secretion of leukotriene C(4) and cytokine TNF-α (tumor necrosis factor-α). The inhibitory action of MELs on mediator secretion was mediated by inhibition of Ca(2+) increase, phosphorylation of MAP kinases and SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) that serve as a molecular machinery for exocytotic membrane fusion., Conclusions: MELs have anti-inflammatory action inhibiting the secretion of inflammatory mediators from mast cells., General Significance: MELs affects two of major intracellular signaling pathways including Ca(2+) increase and MAP kinases. MELs also inhibited the phosphorylation of SNARE proteins that is crucial for not only exocytosis but also intracellular vesicular trafficking., (2011 Elsevier B.V. All rights reserved.)

Patients with depression showed a decrease in plasma and cerebrospinal fluid allopregnanolone (ALLO). But antidepressants increased the contents of ALLO in the rat brain. We examined the antidepressant-like effects of infusion of ALLO into the cerebral ventricle, hippocampus, amygdala, nucleus accumbens, or prefrontal cortex of learned helplessness (LH) rats (an animal model of depression). Of these regions, infusions of ALLO into the cerebral ventricle, the CA3 region of hippocampus, or the central region of amygdala exerted antidepressant-like effects. Infusion of ALLO into the hippocampal CA3 region or the central amygdala did not produce memory deficits or locomotor activation in the passive avoidance and open field tests. It is well documented that ALLO exerts its effects through GABA receptors. Therefore, we examined the antagonistic effects of flumazenil (a GABA receptor antagonist) on the antidepressant-like effects of ALLO. Coinfusion of flumazenil with ALLO into the hippocampal CA3 region, but not into the central amygdala, blocked the antidepressant-like effects of ALLO. However, coinfusion of (+)MK801 (an NMDA receptor antagonist), but not cycloheximide (a protein synthesis inhibitor), blocked the antidepressant-like effects of ALLO in the central amygdala. These results suggest that ALLO exerts antidepressant-like effects in the CA3 region of hippocampus through the GABA system and in the central region of amygdala, dependently on the activation of the glutamatergic mechanisms., (Copyright © 2010 Wiley-Liss, Inc.)

Mast cells play a pivotal role in allergic responses. Antigen stimulation causes elevation of the intracellular Ca(2+) concentration, which triggers the exocytotic release of inflammatory mediators such as histamine. Recent research, including our own, has revealed that SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins such as syntaxin-3, -4, SNAP-23, and VAMP-8 are involved in exocytosis. Although exocytosis in mast cells is Ca(2+) dependent, the target molecule that interacts with Ca(2+) is not clear. Synaptotagmin is a Ca(2+) sensor and regulates exocytosis in neuronal cells. However, the role of synaptotagmin 2, a member of the synaptotagmin family, in exocytosis in mast cells remains controversial. In this study, we investigated the role of synaptotagmin 2 by a liposome-based fusion assay. SNARE proteins (SNAP-23, syntaxin-3, VAMP-8) and synaptotagmin 2 were expressed in Escherichia coli and purified as GST-tagged or His-tagged fusion proteins. These SNARE proteins were incorporated by a detergent dialysis method. Membrane fusion between liposomes was monitored by fluorescence resonance energy transfer between fluorescent-labeled phospholipids. In the presence of Ca(2+), low synaptotagmin 2 concentration inhibited membrane fusion between SNARE-containing liposomes, while high synaptotagmin 2 concentration enhanced membrane fusion. This enhancement required phosphatidylserine as a membrane component. These results suggest that synaptotagmin 2 regulates membrane fusion of SNARE-containing liposomes involved in exocytosis in mast cells, and that this regulation is dependent on synaptotagmin 2 concentration, Ca(2+), and phosphatidylserine., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background: There is emerging evidence that antidepressants may be effective in preventing patients with non-specific and psychotic-like prodromal symptoms, defined as patients at ultra-high risk (UHR) of psychotic disorder, from transitioning to psychosis. However, the mechanism of such an effect is still unknown., Methods: We report the case of a 19-year-old Japanese man determined to be at UHR of psychotic disorder in whom fluvoxamine (one of the antidepressants with sigma-1 receptor agonism) showed preventive effects on psychotic-like prodromal symptoms., Results: Our patient's depressive symptoms were reduced and maintained below remission as a result of treatment with 100 mg/day of fluvoxamine. In addition, it is likely that an additional dose of fluvoxamine (50 mg/day) improved his psychotic-like prodromal symptoms directly, independent of its antidepressive effects., Conclusion: Fluvoxamine, a sigma-1 receptor agonist, may be effective in preventing patients at UHR of psychotic disorder from onset of psychosis via its neuroprotective/neurotropic actions, independent of its antidepressive effects.