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Selective neuronal death or loss in certain brain regions has been well characterized in animal models of transient global cerebral ischemia. However, selective neuronal death in transient focal cerebral ischemia needs more investigation. Therefore, in this study, we studied selective neuronal death in the striatum (caudate putamen) of rats subjected to 15 or 30 min middle cerebral artery occlusion (MCAO). Neuronal death occurred in the dorsolateral field, not in the medial field in 30 min, not 15 min, MCAO-operated rats 5 days after MCAO using neuronal nuclear antigen immunohistochemistry and Fluoro-Jade B histofluorescence staining. In this group, immunoreactivity of glial fibrillary acidic protein in astrocytes was hardly shown in the dorsolateral field, although the immunoreactivity increased in the medial field. In addition, immunoreactivity of ionized calcium binding adapter molecule 1 in microglia was dramatically increased in the dorsolateral, not in the medial, field only in 30 min MCAO-operated rats. Briefly, these results show that at least 30 min of MCAO can evoke selective neuronal death, astrocytic dysfunction and microglial activation in the dorsolateral field of the rat striatum and suggest that a rat model of 30 min MCAO can be used to investigate mechanisms of neuronal death and gliosis following brief transient focal cerebral ischemic events for acute transient ischemic attack.

Neurofilaments (NFs) including neurofilament‑200 kDa (NF‑H), neurofilament‑165 kDa (NF‑M) and neurofilament‑68 kDa (NF‑L) are major protein constituents of the brain, and serve important roles in the regulation of axonal transport. NF alteration is a key feature in the pathogenesis of neurological disorders involving cognitive dysfunction. In the present study, cognitive impairments were investigated, via assessments using the Morris water maze and passive avoidance tests, in mice following chronic systemic treatment with 1 mg/kg scopolamine (SCO) for 4 weeks. SCO‑induced cognitive impairments were significantly observed 1 week following the SCO treatment, and these cognitive deficits were maintained for 4 weeks. However, the NF immunoreactivities and levels were altered differently according to the hippocampal subregion following SCO treatment. NF‑H immunoreactivity and levels were markedly altered in all hippocampal subregions, and were significantly increased 1 week following the SCO treatment; thereafter, the immunoreactivity and levels significantly decreased with time. NF‑M immunoreactivity and levels gradually decreased in the hippocampus and were significantly decreased 4 weeks following SCO treatment. NF‑L immunoreactivity and levels gradually decreased in the hippocampus, and were significantly decreased 2 and 4 weeks following SCO treatment. In conclusion, the results of the present study demonstrated that chronic systemic treatment with SCO induced cognitive impairment from 1 week following SCO treatment, and NF expression was diversely altered according to the hippocampal subregion from 1 week following SCO treatment. These results suggest that SCO‑induced changes in NF expression may be associated with cognitive impairment.

The genus Populus (poplar) belonging to the Salicaceae family has been used in traditional medicine, and its several species show various pharmacological properties including antioxidant and anti-inflammatory effects. No study regarding protective effects of Populus species against cerebral ischemia has been reported. Therefore, in the present study, we examined neuroprotective effects of ethanol extract from Populus tomentiglandulosa (Korea poplar) in the hippocampal cornu ammonis (CA1) area of gerbils subjected to 5 minutes of transient global cerebral ischemia. Pretreatment with 200 mg/kg of P. tomentiglandulosa extract effectively protected CA1 pyramidal neurons from transient global cerebral ischemia. In addition, glial fibrillary acidic protein immunoreactive astrocytes and ionized calcium binding adapter molecule 1 immunoreactive microglia were significantly diminished in the ischemic CA1 area by pretreatment with 200 mg/kg of P. tomentiglandulosa extract. Briefly, our results indicate that pretreatment with P. tomentiglandulosa extract protects neurons from transient cerebral ischemic injury and diminish cerebral ischemia-induced reactive gliosis in ischemic CA1 area. Based on these results, we suggest that P. tomentiglandulosa can be used as a potential candidate for prevention of ischemic injury.

Background. Monoparetic stroke is rare but could be misdiagnosed as peripheral neuropathy. We investigated the prevalence, lesion pattern, stroke mechanism, and long-term prognosis in patients with monoparetic stroke.Methods. 586 acute ischemic stroke patients (including 31 with monoparesis) were studied. Monoparetic stroke was defined as a motor deficit in either an arm or a leg but without facial weakness or speech disturbance. Median follow-up period was 32.0 months. Kaplan-Meier survival curves, log-rank tests, logistic regressions, and Cox proportional hazards models were used for clinical outcome analyses.Results. The mean age (313 men and 273 women) was 67.6 years. Among monoparetic patients, most had cortical (80.6%) and multiple (64.5%) lesions. The main stroke mechanisms were cardioembolism (38.7%) and large artery atherosclerosis (29.0%). Precentral gyrus with additional regions was most frequently involved in monoparesis (45.2%). Upper motor neuron signs were found in only 11 patients (35.5%). Compared with the nonmonoparetic group, these patients had better functional outcomes (6-month modified Rankin scale ≤2) and long-term survival but had comparable risks for further vascular events, including stroke recurrences.Conclusions. Although monoparetic stroke may have a better functional outcome, the risk of the further vascular event seems similar to nonmonoparetic stroke.

Objective Insulin resistance (IR) is a distinct and early feature of type 2 diabetes mellitus and metabolic syndrome. IR is thought to play a vital role in cognitive impairment. We conducted this study to understand the early characteristics of cognitive dysfunctions attributable to IR. Methods This study included 85 consecutive non-diabetic elderly participants with mild cognitive impairment (MCI). IR was estimated with the homeostasis model assessment of insulin resistance (HOMA-IR). Cognitive performances were analyzed as a function of scores on the HOMA-IR. Results The group analysis those with and without IR did not show any differences in the cognitive performance although higher HOMA-IR was closely associated with lower performances in immediate recall on the Seoul Verbal Learning Test (SVLT-I) (r = −0.244, p = 0.026) and Controlled Oral Word Association Test (COWAT) (r = −0.270, p = 0.013). In subgroup analysis by APOE status, SVLT-delayed (p = 0.027) and COWAT (p = 0.016) scores were found to be significantly lower in the IR than the non-IR among those with APOE e4 allele. In multiple regression analysis, impairment on the COWAT remained significantly correlated with scores on HOMA-IR (β = −0.271, t = −2.340, p = 0.022). However, IR status was identified to interact with APOE e4 carriership toward poor performances in the COWAT (β = −0.335, t = −2.285, p = 0.026). Conclusion This study found a domain-specific impact of HOMA-IR scores on cognitive performances in non-diabetic patients with MCI. This association was profound only in APOE e4carriers. Copyright © 2014 John Wiley & Sons, Ltd.

We have investigated the electric-field intensity distributions and characteristics of the whispering-gallery mode (WGM) from a planar microdisk using a three-dimensional finite-difference time-domain method. Silicon nitride (Si 3 N 4 ) planar microdisks on silica (SiO 2 ) substrates have been systematically analyzed considering the effects of the sidewall angle, etching depth, and height. Superpositioning of the TE and TM modes which is caused by the skew effect according to the sidewall angle has been demonstrated. Furthermore, the mode splitting caused by the change from single mode to multi-mode regimes due to an increase in the height has been analyzed. Several planar microdisks of Si 3 N 4 on SiO 2 were fabricated, and their resonance characteristics were probed by using micro-photoluminescence spectroscopy. A quality factor of 5×10 3 for microdisks with a diameter of 3.5 μm and sidewall angle of 35° was observed in the visible range. The WGMs of fabricated microdisk were analyzed according to the details of the model and found to be in good agreement

Background: Rhabdomyolysis is a syndrome of skeletal muscle breakdown with leakage of muscle contents into blood stream. Variable disorders affecting muscle membrane or its energy supply can cause rhabdomyolysis. Case Report: We report a patient with rapidly progressive dementia who developed severe parkinsonism after rhabdomyolysis in the course of the illness. Functional neuroimaging studies revealed diffuse cortical hypometabolism and severe nigrostriatal dopaminergic dysfunction. Conclusion: This case suggests that the special attentions should be paid on evaluation for rhabdomyolysis in some demented patients. J Neurocrit Care 2014;7(1):56-59

Objective: Limbic encephalitis (LE) is characterized by rapid development of impaired cognitive function, seizure and psychiatric symptoms. Brain 18fluoro labelled deoxyglucose (18FDG)-positron emission tomography (PET) typically showed glucose hypermetabolism in the temporomesial region in the acute stage. Although several studies about brain 18FDG-PET in LE have been reported, serial 18FDG-PET findings during the course of the disease are limited. The purpose of this study is to analyze serial 18FDGPET findings in LE and to compare them with the results of neuropsychological test. Methods: We studied prospectively two patients diagnosed as LE using clinical criteria. They underwent serial brain magnetic resonance imaging (MRI) and 18FDG-PET scans. They also received detailed neuropsychological tests. Results: Initial 18FDG-PET presented glucose hypermetabolism in unilateral temporomesial region without obvious abnormalities in brain MRI. Follow-up 18FDG-PET images obtained three month later displayed hypometabolism in both temporomesial region. Correspondingly, neuropsychological studies revealed prominent visuospatial and verbal memory deficits. Conclusion: The initial 18FDG-PET was very sensitive in visualizing the disease process compared with MRI and suggesting more markedly functional impairment than structural damage in early stage of LE. This was well correlated with cognitive dysfunction measured by neuropsychological test such as anterograde episodic memory loss involving both verbal and non-verbal materials.

Compelling evidence from preclinical and clinical studies has shown that mild hypothermia is neuroprotective against ischemic stroke. We investigated the neuroprotective effect of post-risperidone (RIS) treatment against transient ischemic injury and its mechanisms in the gerbil brain. Transient ischemia (TI) was induced in the telencephalon by bilateral common carotid artery occlusion (BCCAO) for 5 min under normothermic condition (37 &plusmn, 0.2 &deg, C). Treatment of RIS induced hypothermia until 12 h after TI in the TI-induced animals under uncontrolled body temperature (UBT) compared to that under controlled body temperature (CBT) (about 37 &deg, C). Neuroprotective effect was statistically significant when we used 5 and 10 mg/kg doses (p &lt, 0.05, respectively). In the RIS-treated TI group, many CA1 pyramidal neurons of the hippocampus survived under UBT compared to those under CBT. In this group under UBT, post-treatment with RIS to TI-induced animals markedly attenuated the activation of glial cells, an increase of oxidative stress markers [dihydroethidium, 8-hydroxy-2&prime, deoxyguanosine (8-OHdG), and 4-Hydroxynonenal (4-HNE)], and a decrease of superoxide dismutase 2 (SOD2) in their CA1 pyramidal neurons. Furthermore, RIS-induced hypothermia was significantly interrupted by NBOH-2C-CN hydrochloride (a selective 5-HT2A receptor agonist), but not bromocriptine mesylate (a D2 receptor agonist). Our findings indicate that RIS-induced hypothermia can effectively protect neuronal cell death from TI injury through attenuation of glial activation and maintenance of antioxidants, showing that 5-HT2A receptor is involved in RIS-induced hypothermia. Therefore, RIS could be introduced to reduce body temperature rapidly and might be applied to patients for hypothermic therapy following ischemic stroke.

We demonstrate significant enhancement of an effective Q-factor in a silica planar waveguide-based asymmetric Mach–Zehnder interferometer (AMZI) coupled with a microdisk. To enhance the Q-factor, which is required to more effectively measure the signal changes occurring during biochemical events, the structure utilizes resonance mode splitting. This phenomenon is observed through power cancellation at the same amplitude and a 180° phase difference of each path in the AMZI. In this study, we experimentally showed the effective Q-factor enhancement by comparing resonance characteristics of a fabricated microdisk, AMZI, and the proposed structure at equal fabrication conditions. We measured an effective Q-factor of 9.15 × 104 with a 22 dB extinction ratio.

The authors inadvertently forgot to provide the following funding information in the original publication: This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF), funded by the Ministry of Science and ICT (2018R1A6A3A11041118).

Ischemic preconditioning (IPC) is induced by exposure to brief durations of transient ischemia, which results in ischemic tolerance to a subsequent longer or lethal period of ischemia. In the present study, the effects of IPC (2 min of transient cerebral ischemia) were examined on immunoreactivity of platelet‑derived growth factor (PDGF)‑BB and on neuroprotection in the gerbil hippocampal CA1 region following lethal transient cerebral ischemia (LTCI; 5 min of transient cerebral ischemia). IPC was subjected to a 2‑min sublethal ischemia and a LTCI was given 5‑min transient ischemia. The animals in all of the groups were given recovery times of 1, 2 and 5 days and change in PDGF‑BB immunoreactivity was examined as was the neuronal damage/death in the hippocampus induced by LTCI. LTCI induced a significant loss of pyramidal neurons in the hippocampal CA1 region 5 days after LTCI, and significantly decreased PDGF‑BB immunoreactivity in the CA1 pyramidal neurons from day 1 after LTCI. Conversely, IPC effectively protected the CA1 pyramidal neurons from LTCI and increased PDGF‑BB immunoreactivity in the CA1 pyramidal neurons post‑LTCI. In conclusion, the results demonstrated that LTCI significantly altered PDGF‑BB immunoreactivity in pyramidal neurons in the hippocampal CA1 region, whereas IPC increased the immunoreactivity. These findings indicated that PDGF‑BB may be associated with IPC‑mediated neuroprotection.

Summary Few studies regarding the anatomical distribution of motor neurons innervating muscles of the arm have been demonstrated in avian brains. The purpose of this study was to finely determine the localization of cerebral neurons innervating the biceps brachii muscle in the pigeon. The cholera toxin B subunit (CTB) was employed as a retrograde tracer to determine the location of neurons controlling the biceps brachii muscle in the telencephalon following intramuscular injection in male pigeons (n = 7), which were killed 14 days after intramuscular injection with CTB. We found that CTB-labelled neurons were located contralaterally in the hyperpallium apicale of the rostral telencephalon and that most of the CTB-labelled neurons were pyramidal in shape. This study shows that CTB is easily taken up by nerve terminals which innervate the biceps brachii muscle of the pigeon and that cerebral motor neurons controlling the biceps brachii muscle are located in the hyperpallium apicale.

BACKGROUND Atomoxetine has been widely used for the treatment of attention-deficit/ hyperactivity disorder. ATX has additional abilities such as antagonistic effects on the N-methyl-Daspartate receptors (NMDARs) and benefit effects in some animal models of neurological disorders. However, there were few studies regarding protective effects and related mechanisms of ATX against cerebral ischemic insults. OBJECTIVE The objective of this study is to investigate neuroprotection of ATX pretreatment and its mechanisms in the hippocampal cornu ammonis 1 (CA1) region following transient global cerebral ischemia in gerbils. METHOD Gerbils were subjected to transient global cerebral ischemia induced by the occlusion of common carotid arteries for 5 min. Thirty mg/kg of ATX was administrated intraperitoneally once daily for 3 days before ischemic surgery. To examine neuroprotective effects of ATX, we carried out neuronal nuclear antigen immunohistochemistry and Fluoro-Jade B histofluorescence staining. In addition, immunoreactivities of NMDAR1, NMDAR2A/B, B-cell lymphoma 2 (Bcl-2) and Bcl-2- associated X protein (Bax) are closely related with neuroexcitotoxicity. RESULTS ATX pretreatment reduced ischemia-induced hyperactivity and protected CA1 pyramidal neurons from ischemia. Pretreatment with ATX significantly attenuated ischemia-induced increases of NMDAR1 and NMDAR2A/B immunoreactivities in the CA1 pyramidal neurons at early time following ischemia. In addition, significant ischemia-induced alterations of Bcl-2 and Bax immunoreactivities were not observed in the ATX-treated group following ischemia. CONCLUSION These results show that pretreatment with ATX protected against ischemic neuronal via inhibition of ischemia-induced excitotoxicity at early time following transient global cerebral ischemia.

Glycogen synthase kinase 3β (GSK-3β) is a key downstream protein in the PI3K/Akt pathway. Phosphorylation of serine 9 of GSK-3β (GSK-3β activity inhibition) promotes cell survival. In this study, we examined changes in expressions of GSK-3β and phosphorylation of GSK-3β (p-GSK-3β) in the gerbil hippocampal CA1 area after 5 min of transient cerebral ischemia. GSK-3β immunoreactivity in the CA1 area was increased in pyramidal cells at 6 h after ischemia–reperfusion. It was decreased in CA1 pyramidal cells from 12 h after ischemia–reperfusion, and hardly detected in the CA1 pyramidal cells at 5 days after ischemia–reperfusion. p-GSK-3β immunoreactivity was slightly decreased in CA1 pyramidal cells at 6 and 12 h after ischemia–reperfusion. It was significantly increased in these cells at 1 and 2 days after ischemia–reperfusion. Five days after ischemia–reperfusion, p-GSK-3β immunoreactivity was hardly found in CA1 pyramidal cells. However, p-GSK-3β immunoreactivity was strongly expressed in astrocytes primarily distributed in strata oriens and radiatum. In conclusion, GSK-3β and p-GSK-3β were significantly changed in pyramidal cells and/or astrocytes in the gerbil hippocampal CA1 area following 5 min of transient cerebral ischemia. This finding indicates that GSK-3β and p-GSK-3β are closely related to delayed neuronal death.

Myelin plays an important role in learning and memory, and degradation of myelin is a key feature in the pathogenesis of neurological disorders involving cognitive dysfunction. Myelin basic protein (MBP) is one of the most abundant structural proteins in myelin and is essential for myelin formation and compaction. In this study, we first examined changes in the distribution of MBP-immunoreactive myelinated fibers and MBP levels according to hippocampal subregion in mice following chronic systemic treatment with 1 mg/kg scopolamine (SCO) for 4 weeks. We found that SCO-induced cognitive impairments, as assayed by the water maze and passive avoidance tests, were significantly reduced 1 week after SCO treatment and the impairments were maintained without any hippocampal neuronal loss. MBP-immunoreactive myelinated fibers were easily detected in the stratum radiatum and lacunosum-moleculare of the hippocampus proper (CA1–3 region) and in the molecular and polymorphic layers of the dentate gyrus. The distribution of MBP-immunoreactive myelinated fibers was not altered 1 week after SCO treatment. However, the density of MBP-immunoreactive myelinated fibers was significantly decreased 2 weeks after SCO treatment; thereafter, the density gradually, though not significantly, decreased with time. In addition, the changing pattern of MBP levels in the hippocampus following SCO treatment corresponded to immunohistochemical changes. In brief, this study shows that chronic systemic treatment with SCO induced significant degradation of MBP in the hippocampus without neuronal loss at least 2 weeks after SCO treatment, although cognitive impairments occurred 1 week after SCO treatment.

In this paper, an effective quality-factor is analyzed for asymmetric Mach-Zehnder interferometer (AMZI) with ring resonator sensor. The device is designed with AMZI to interference with the optical input of the ring resonator based on silica semiconductor process. The design of device satisfy a critical resonance at out of phase condition through asymmetric power split ratio. According to operation principle of Mach-Zehnder interferometer, the critical resonance occurs when the power passing through asymmetric arm is in a range of ring resonator power variation. Our simulation shows that the Q-factor of the device is enhanced from 1161.9 to 5342.5 if a RR is coupled to an arm of AMZI.

Tanshinone I (TsI), a lipophilic diterpene extracted from Danshan (Radix Salvia miltiorrhizae), exerts neuroprotection in cerebrovascular diseases including transient ischemic attack. In this study, we examined effects of TsI on cell proliferation and neuronal differentiation in the subgranular zone (SGZ) of the mouse dentate gyrus (DG) using Ki-67, BrdU and doublecortin (DCX) immunohistochemistry. Mice were treated with 1 and 2 mg/kg TsI for 28 days. In the 1 mg/kg TsI-treated-group, distribution patterns of BrdU, Ki-67 and DCX positive ((+)) cells in the SGZ were similar to those in the vehicle-treated-group. However, in the 2 mg/kg TsI-treated-group, double labeled BrdU(+)/NeuN(+) cells, which are mature neurons, as well as Ki-67(+), DCX(+) and BrdU(+) cells were significantly increased compared with those in the vehicle-treated-group. On the other hand, immunoreactivities and protein levels of Wnt-3, β-catenin and serine-9-glycogen synthase kinase-3β (p-GSK-3β), which are related with morphogenesis, were significantly increased in the granule cell layer of the DG only in the 2 mg/kg TsI-treated-group. Therefore, these findings indicate that TsI can promote neurogenesis in the mouse DG and that the neurogenesis is related with increases of Wnt-3, p-GSK-3β and β-catenin immunoreactivities.

Background and study aims: Endoscopic bilateral drainage for inoperable malignant hilar biliary strictures (HBS) using metal stents is considered to be technically difficult. Furthermore, endoscopic revision of bilateral stenting after occlusion can be challenging. This study was performed to evaluate the long-term efficacy of endoscopic bilateral stent-in-stent placement of cross-wired metallic stents in high-grade malignant HBS and planned endoscopic bilateral revision. Patients and methods: A total of 84 patients with inoperable high-grade malignant HBS were enrolled from three academic tertiary referral centers. Two cross-wired metal stents were inserted using a bilateral stent-in-stent placement method. Bilateral endoscopic revision was also performed during follow-up using either identical metal stents or plastic stents. The main outcome measurements were technical and functional success, complications, stent patency, and endoscopic revision efficacy. Results: The technical and clinical success rates of endoscopic bilateral stent-in-stent placement of cross-wired metallic stents were 95.2 % (80 /84) and 92.9 % (78 /84), respectively. Median patency (range) and survival were 238 days (10 – 429) and 256 days (10 – 1130), respectively. Obstruction of primary bilateral stents occurred in 30.8 % (24 /78) of patients with functionally successful stent placement. The technical and clinical success rates of planned bilateral endoscopic revision for occluded stents were 83.3 % (20 /24) and 79.2 % (19 /24), respectively. For revision, bilateral metallic stents were placed in 11 patients (55.0 %); the remaining patients received plastic stents. Conclusions: Palliative endoscopic bilateral stent-in-stent placement of cross-wired metallic stents was effective in patients with inoperable HBS. Revision endoscopic bilateral stenting may be feasible and successful in cases where the primary deployed metal stents are occluded.

Our results show that cervical vestibular-evoked myogenic potential (cVEMP) or ocular VEMP (oVEMP) abnormalities in the recurrent benign paroxysmal positional vertigo (BPPV) group were significantly higher than those in the non-recurrent BPPV group. Therefore, we can infer that VEMP abnormality is one of risk factors for BPPV recurrence.This prospective study aimed to test the hypothesis that otolith dysfunction using the VEMP test is a cause of recurrence of BPPV.cVEMP and oVEMP tests using 500 Hz tone-burst stimuli were performed on 16 patients with recurrent BPPV between March 2010 and December 2011. Both VEMP tests were performed in 20 patients with non-recurrent BPPV.The differences in age, sex, and involved canal between the recurrent and non-recurrent BPPV groups were not significant. Abnormal cVEMP responses were detected in 5 of 16 (31.3%) subjects in the recurrent BPPV group and abnormal oVMEP responses were detected in 4 of 16 (25%) subjects in the recurrent BPPV group. When we defined VEMP abnormality as an abnormal cVEMP or abnormal oVEMP, VEMP abnormalities were detected in eight (50%) subjects in the recurrent BPPV group and in three (15%) subjects in the non-recurrent BPPV group; the difference between groups was significant.

In this paper, we have theoretically analyzed and designed a dielectric multi-layer sensor with a SPR (surface plasmon resonance) using analytical calculation and FDTD (finite difference time-domain) methods. The proposed structure is composed of periodic layer and thin metal film. It has many advantages. One of that is a high sensitivity of the SPR. Another is a high Q-factor of the characteristics in the PhC (photonic crystals) micro-cavity structure. The incident light has double resonance characteristics, because the filtered light by PhC structure, dielectric multi-layer, is met the thin metal film for SPR effect. We have also observed the change of resonance characteristics according to the variation of effective index on the metal film.

We present an opto-electrical predistortion optical transmitter showing significant reductions in both 3rd-order and 5th-order intermodulations (IM3 and IM5). The simultaneous reductions of IM3 and IM5 are achieved by choosing an appropriate bias current and RF input power for the LD, obtained by the analysis of the 3rd-order to 5th-order intermodulation distortion ratio (TFR). In our experiments, two DFB-LDs (master and slave LDs) with a similar performance are used; the matching circuits of the two LDs are designed to have equal properties. The experimental results show that reductions of 30 dB in the IM3 and 12 dB in the IM5 are achieved simultaneously under the optimum TFR conditions of a 12 mA bias current and a 0 dBm RF power at 2.2 GHz.

We propose and analyze a high effective Q-factor triangular ring resonator (TRR) coupled with an asymmetric Mach–Zehnder interferometer (AMZI), in which the long evanescent fields on a total internal reflection (TIR) mirror in the TRR and the field cancelation by the phase difference of each path in the AMZI are utilized. The TRR is employed in order to more effectively measure the quantities that occur during biological events because the evanescent field of the TIR mirror with its sharp incident angle is influenced by the Goos–Hanchen shift. In this paper, we report upon the AMZI-coupled TRR sensor structure with the high effective Q-factor of about 10 5 obtained through the optimization of the AMZI path-length. The sensitivity of the resonance shift when changing the refractive index of 1 × 10 − 4 at the incidence angle of 22.92° has been identified to be as high as 0.48 × 10 4 nm/RIU. In addition, the power sensitivity of the AMZI-coupled TRR with a 17 dB attenuation is 5.7 × 10 5 dB/RIU.

We propose a novel micro surface plasmon resonance (SPR) sensor system based on polymer materials. The proposed SPR system consists of the incident medium with polymer waveguide and the gold thin film for sensing area. Using a polymer optical waveguide instead of a prism in SPR sensing system offers miniaturization, low cost, and potable sensing capability. The whole device performance was analyzed using the finite-difference time domain method. The optimum gold thickness in the attenuated total reflection mirror of polymer waveguide is around 50 nm and the resonance angle to generate surface plasmon wave is 68 degrees.

This paper presents a new approach to a time and energy efficient online complete coverage solution for a mobile robot. While most conventional approaches strive to reduce path overlaps, this work focuses on smoothing the coverage path to reduce accelerations and yet to increase the average velocity for faster coverage. The proposed algorithm adopts a high-resolution grid map representation to reduce directional constraints on path generation. Here, the free space is covered by three independent behaviors: spiral path tracking, wall following control, and virtual wall path tracking. Regarding the covered region as a virtual wall, all the three behaviors adopt a common strategy of following the (physical or virtual) wall or obstacle boundaries for close coverage. Wall following is executed by a sensor-based reactive path planning control process, whereas the spiral (filling) path and virtual wall path are first modeled by their relevant parametric curves and then tracked via dynamic feedback linearization. For complete coverage, these independent behaviors are linked through a new path linking strategy, called a coarse-to-fine constrained inverse distance transform (CFCIDT). CFCIDT reduces the computational cost compared to the conventional constrained inverse distance transform (CIDT), which applies a region growing starting from the current robot position to find the nearest unexplored cell as well as the shortest path to it while constraining the search space. As for experimental validation, performance of the proposed algorithm is compared to those of conventional coverage techniques to demonstrate its completeness of coverage, energy and time efficiency, and robustness to the environment shape or the initial robot pose.

The direct intensity modulation of a three-guide coupled rectangular ring laser having bidirectional lasing characteristics is reported for the first time. The rectangular laser cavity consists of four low loss total internal reflection mirrors and an output coupler made out of three passive coupled waveguides. The laser is fabricated using a total cavity length of 580 μm with active section lengths of 250 μm. For both the clockwise and counterclockwise circulating directions, a lasing threshold of around 38 mA is obtained at room temperature under continuous wave operation. A maximum 3-dB modulation bandwidth of approximately 3.2 GHz is observed in both circulating directions.

The imbalance between three-repeat (3R) and four-repeat (4R) tau isoforms produced by the alternative splicing of tau exon 10 leads to neuronal instability and eventual neurodegeneration in tauopathy. However, the role of altered 3R/4R tau ratio in Alzheimer's disease (AD) remains controversial. It has been shown that the expression of 3R tau is modulated by peptide amyloid β (Aβ) and that 3R tau levels increase with the progression of AD. The incidence of AD increases in patients with type 2 diabetes mellitus (T2DM), and the comorbidity of these disorders is closely associated with both aging and disease duration. To investigate whether changes in 3R and 4R tau isoforms are involved in AD pathology pertaining to age-related T2DM, the expression of tau isoforms and their relationship with AD-like tau pathology were examined in a spontaneous T2DM model using aged Otsuka Long-Evans Tokushima Fatty (OLETF) rats with obesity. An AD-like pathology consisting of increased aggregates in the neuronal cytoplasm and a loss of synaptic proteins was observed in these rats. The aggregates were reactive with a 3R tau-specific, but not 4R tau-specific, antibody. In contrast to 4R tau, the level of 3R tau profoundly increased and the proteins were prone to taking toxic phosphorylated and truncated forms. Taken together, these findings suggest that increased 3R tau may contribute to AD-like tau pathology in a chronic T2DM model. Thus, the restoration of normal 3R tau expression should be considered as an important therapeutic strategy in the treatment of AD.

We have systematically designed and experimentally demonstrated the opto-electrical predistortion optical transmitter using microwave circuit modelling for reducing the nonlinearity of the distributed-feedback laser diode (DFD-LD). The DFB-LD is analyzed using microwave circuits model based on rate equations. Through the system-level simulation for predistortion method, the optimized characteristics of the RF components in the system are confirmed. The simulated and experimental results show the reduced distortion products. These results are analyzed as the evaluation parameters for the miniaturization and optimization of the opto-electrical predistortion method in radio-over-fiber systems.

We propose a novel ring structure based on the stadium-shaped ring resonator (SSRR) with dual photonic crystal microcavity (DPCM) for biosensor and analyzed the sensing characteristics. The Q-factor of the photonic crystal microcavity (PCM) can be significantly enhanced when the PCM or DPCM has the same resonance condition as the SSRR. The simulation results show that the Q-factor of the SRR with DPCM was increased by three times in comparison with single PCM structure. We also defined a mutual interference between two PCMs. Assuming a detectable spectral resolution of 10 picometers, a refractive index resolution of 3.03×10-5 can be measured on the SSRR-DPCM.

BACKGROUND AND STUDY AIMS: Endoscopic transpapillary gallbladder drainage for symptomatic gallbladder disease is a safe and effective bridge therapy in patients at high risk for surgery or who have terminal liver disease and are awaiting transplantation. However, there are few reports on long-term results in terms of stent patency and clinical course. Our study was designed to investigate the long-term patency and clinical course after endoscopic transpapillary gallbladder stenting (ETGS) in patients with symptomatic gallbladder disease. PATIENTS AND METHODS: A total of 29 patients who were unsuitable for cholecystectomy underwent ETGS from June 2006 to March 2010 using a 7-Fr double-pigtail stent between the gallbladder and the duodenum. Their clinical progress, adverse events, and stent patency after ETGS were recorded prospectively in two tertiary referral centers. RESULTS: Technically, ETGS was successful in 23 (79.3 %) of the 29 patients. The mean procedure time was 22.4 ± 11.5 min. Postprocedure adverse events were mild pancreatitis (8.7 %) and cholestasis (8.7 %), all of which resolved with conservative management. During the follow-up period (median 586 days, range 11 – 1403 days), 20 patients were analyzed as per protocol, and scheduled follow-up was performed. Late adverse events developed in four patients (20 %), including distal migration (n = 2), cholangitis (n = 1), and recurrent biliary pain (n = 1). The remaining 16 patients were followed for more than 12 months (nine patients were followed for more than 24 months). Median stent patency was 760 days, as determined by the Kaplan-Meier method. CONCLUSIONS: As a primary therapy, ETGS is technically feasible and effective in patients who are unsuitable for cholecystectomy. ETGS may also provide long-term stent patency without the need for scheduled stent exchanges.

This paper presents a new complete coverage algorithm of a robotic vacuum cleaner (RVC) with a low-cost sensor in an unknown environment. To achieve complete coverage, the RVC must have navigation systems for precise position estimation with localization and a prior map or a map using information that has been continuously collected from the environment. To do this, two-dimensional laser range finders and vision sensors are becoming increasingly popular in mobile robotics, and various methods using sensors like these have been introduced by many researchers. However, it is difficult to apply the methods to sensors used in most RVCs due to their constraints. In this paper, we present a new method applied to most RVCs. For developing the method, we considered the two main problems of maintaining low computational load, and coping with low-cost sensor systems with limited range, detection uncertainty and measurement error. To solve the problems, we propose an assumption that major structures of an indoor env...

Background and study aim Minimally invasive treatment has become a mainstay management strategy for early gastric cancer (EGC). Full-thickness incision of the gastric wall using natural orifice transluminal endoscopic surgery (NOTES) has been reported but is not easily applicable in clinical settings at present. The aim of the current study was to assess the feasibility of hybrid NOTES, which consists of endoscopic full-thickness gastric resection and a laparoscopic lymphadenectomy. Patients and methods This was a prospective, pilot study at a single tertiary care referral center. A total of 14 patients with EGC located above the lower third of the stomach underwent hybrid NOTES. Clinically, the patients had contraindications to exclusive treatment using endoscopic submucosal dissection (ESD). The main outcome measure was technical success of hybrid NOTES. Results All cases were resected en bloc with negative surgical margins. Histologically, four cases were mucosal cancers, and 10 cases were submucosal cancers. The median tumor size was 26 mm (range 12 - 90 mm). Lymphatic vessel invasion was found in four cases without lymph node metastasis (LNM). The median number of obtained lymph nodes was 18 (range 7 - 67). LNM was discovered in one case of undifferentiated submucosal cancer without lymphovascular invasion. Hybrid NOTES was conducted without intraoperative or postoperative adverse events in nine cases. The median operating time and estimated blood loss of successful cases were 143 minutes (range 110 - 253 minutes) and 16 mL (range 5 - 30 mL), respectively. The median hospital stay was 6 days (range 4 - 10 days). Five cases were converted to a subtotal gastrectomy for various reasons. Conclusions Hybrid NOTES could be a bridge between endoscopic resection and laparoscopic surgery and may prevent extensive gastrectomy in patients with EGC.

The coverage ability is one of essential techniques for the Ro botic Vacuum Cleaner (RVC). Most of the RVCs rely on random or regular pattern movement to cover a target space due to the technical difficulties to implement localization and map and constraints of hardwares such as contr oller and sensors. In this paper, we consider two main issues which are low computational load and using sensors with very limited sensing capabilities. First, in our approach, computing procedures to build map and detect the RVC's position are minimized by simplifying data obtained from sensors. To reduce computational load, it needs s imply presenting an environment with objects of various shapes. Another isuue mentioned above is regarded as on e of the most important problems in our approach, because we consider that many RVCs use low-cost sensor systems such as an infrared sensor or ultrasonic sensor with limited capabilities in limited range, detection uncertainty, measurement noise, etc. Methods presented in this paper are able to apply to general RVCs equipped with these sen sors. By both simulation and real experiment, we evaluate our method and verify that the proposed method guarant ees a complete coverage.

We have systematically designed and realized the optical feedforward transmitter using microwave circuit model of distributed-feedback laser diode (DFB LD) based on rate equations. Through the system-level simulation for the optical feedforward method, the nonlinearity of DFB-LD is analyzed, and the optimized characteristics of the RF components in the system are confirmed by using a microwave simulator. The experimental and simulated results show the reduced distortion products and enhanced spurious-free dynamic ranges are in good agreement at 2.4 GHz. These results are analyzed as the evaluation parameters for the miniaturization and optimization of the feedforward compensation method in radio-over-fiber systems. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 192–195, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24007

This paper describes a geometrically constrained Extended Kalman Filter (EKF) framework for a line feature based SLAM, which is applicable to a rectangular indoor environment. Its focus is on how to handle sparse and noisy sensor data, such as PSD infrared sensors with limited range and limited number, in order to develop a low-cost navigation system. It has been applied to a vacuum cleaning robot in our research. In order to meet the real-time objective with low computing power, we develop an efficient line feature extraction algorithm based upon an iterative end point fit (IEPF) technique assisted by our constrained version of the Hough transform. It uses a geometric constraint that every line is orthogonal or parallel to each other because in a general indoor setting, most furniture and walls satisfy this constraint. By adding this constraint to the measurement model of EKF, we build a geometrically constrained EKF framework which can estimate line feature positions more accurately as well as allow their covariance matrices to converge more rapidly when compared to the case of an unconstrained EKF. The experimental results demonstrate the accuracy and robustness to the presence of sensor noise and errors in an actual indoor environment.

A 74-year-old woman with left hemiparesis due to a previous stroke presented with the sudden development of cognitive impairment and episodic complex visual hallucinations as manifestations of nonconvulsive status epilepticus (NCSE). Neuropsychological tests performed during NCSE demonstrated deficits encompassing several cognitive domains. The short-lasting complex visual hallucinations were stereotypical, vivid, and accompanied by intense fear. The seizure activity in the right temporo-parieto-occipital region, as documented by SISCOM and electroencephalogram (EEG) recording, was thought to be due to an unusual clinical presentation of NCSE. Subcortical cerebromalacia likely blocked the propagation route, restricting the ictal activities within this area.

A 41-year-old man with progressive quadriparesis and generalized tingling sensation showed spontaneous upbeating nystagmus and horizontal gaze-evoked nystagmus (video at [Neurology.org][1]). The initial diffusion-weighted images showed an equivocal hyperintensity at midline of rostral medulla (upper row). Follow-up MRIs (lower row) showed characteristic heart appearance sign (figure). [1]: http://neurology.org/lookup/doi/10.1212/WNL.0000000000004634

Low survival rate occurs in patients who initially experience a spontaneous return of circulation after cardiac arrest (CA). In this study, we induced asphyxial CA in adult male Sprague-Daley rats, maintained their body temperature at 37 ± 0.5°C, and then observed the survival rate during the post-resuscitation phase. We examined neuronal damage in the hippocampus using cresyl violet (CV) and Fluore-Jade B (F-J B) staining, and pro-inflammatory response using ionized calcium-binding adapter molecule 1 (Iba-1), glial fibrillary acidic protein (GFAP), and tumor necrosis factor-alpha (TNF-α) immunohistochemistry in the hippocampus after asphyxial CA in rats under normothermia. Our results show that the survival rate decreased gradually post-CA (about 63% at 6 hours, 37% at 1 day, and 8% at 2 days post-CA). Rats were sacrificed at these points in time post-CA, and no neuronal damage was found in the hippocampus until 1 day post-CA. However, some neurons in the stratum pyramidale of the CA region in the hippocampus were dead 2 days post-CA. Iba-1 immunoreactive microglia in the CA1 region did not change until 1 day post-CA, and they were activated (enlarged cell bodies with short and thicken processes) in all layers 2 days post-CA. Meanwhile, GFAP-immunoreactive astrocytes did not change significantly until 2 days post-CA. TNF-α immunoreactivity decreased significantly in neurons of the stratum pyramidale in the CA1 region 6 hours post-CA, decreased gradually until 1 day post-CA, and increased significantly again 2 days post-CA. These findings suggest that low survival rate of normothermic rats in the early period of asphyxia-induced CA is related to increased TNF-α immunoreactivity, but not to neuronal damage in the hippocampal CA1 region.

Calbindin D-28K (CB), a Ca2+-binding protein, maintains Ca2+ homeostasis and protects neurons against various insults. Hyperthermia can exacerbate brain damage produced by ischemic insults. However, little is reported about the role of CB in the brain under hyperthermic condition during ischemic insults. We investigated the effects of transient global cerebral ischemia on CB immunoreactivity as well as neuronal damage in the hippocampal formation under hyperthermic condition using immunohistochemistry for neuronal nuclei (NeuN) and CB, and Fluoro-Jade B histofluorescence staining in gerbils. Hyperthermia (39.5 ± 0.2°C) was induced for 30 minutes before and during transient ischemia. Hyperthermic ischemia resulted in neuronal damage/death in the pyramidal layer of CA1–3 area and in the polymorphic layer of the dentate gyrus at 1, 2, 5 days after ischemia. In addition, hyperthermic ischemia significantly decreaced CB immunoreactivity in damaged or dying neurons at 1, 2, 5 days after ischemia. In brief, hyperthermic condition produced more extensive and severer neuronal damage/death, and reduced CB immunoreactivity in the hippocampus following transient global cerebral ischemia. Present findings indicate that the degree of reduced CB immunoreactivity might be related with various neuronal damage/death overtime and corresponding areas after ischemic insults.

SummaryBackground The relationship between relative adrenal insufficiency (RAI) and chronic liver disease is unclear. Aim To determine the frequency with which RAI is observed in noncritically ill patients at various stages of chronic liver disease, and the correlation between RAI and disease severity and long-term mortality. Methods In total, 71 non-critically ill patients with liver cirrhosis (n = 54) and chronic hepatitis (n = 17) were evaluated prospectively. A short stimulation test (SST) with 250 μg of corticotrophin was performed to detect RAI. RAI was defined as an increase in serum cortisol of

In this paper, we propose a surface plasmon resonance (SPR) sensor with metallic nano-particles, which is based on the Kretschmann configuration for reflective-type measurement with enhanced sensitivity. The proposed structure is analyzed and compared with a conventional Kretschmann configuration by using 3D finite-difference time-domain method. The proposed structure is composed of semi-spherical nano-particles and a thin cladding layer. The evanescent field on the metallic structure is enhanced by the factor of 2.7, where the diameter of nano-particles, fill factor, and thickness of cladding film layer T F are 30 nm, 50 %, and 40 nm, respectively. On the other hand, the enhancement of the evanescent field in the conventional SPR sensor is 1.7 for the same TF. Because of the enhanced evanescent field, the sensitivity of our proposed sensor is maximized to 137.1 degree/RIU while that of a conventional SPR sensor is 99.6 degree/RIU.

Insulin resistance (IR) is a distinct and early feature of type 2 diabetes mellitus and metabolic syndrome. IR is thought to play a vital role in cognitive impairment. We conducted this study to understand the early characteristics of cognitive dysfunctions attributable to IR.This study included 85 consecutive non-diabetic elderly participants with mild cognitive impairment (MCI). IR was estimated with the homeostasis model assessment of insulin resistance (HOMA-IR). Cognitive performances were analyzed as a function of scores on the HOMA-IR.The group analysis those with and without IR did not show any differences in the cognitive performance although higher HOMA-IR was closely associated with lower performances in immediate recall on the Seoul Verbal Learning Test (SVLT-I) (r = -0.244, p = 0.026) and Controlled Oral Word Association Test (COWAT) (r = -0.270, p = 0.013). In subgroup analysis by APOE status, SVLT-delayed (p = 0.027) and COWAT (p = 0.016) scores were found to be significantly lower in the IR than the non-IR among those with APOE ε4 allele. In multiple regression analysis, impairment on the COWAT remained significantly correlated with scores on HOMA-IR (β = -0.271, t = -2.340, p = 0.022). However, IR status was identified to interact with APOE ε4 carriership toward poor performances in the COWAT (β = -0.335, t = -2.285, p = 0.026).This study found a domain-specific impact of HOMA-IR scores on cognitive performances in non-diabetic patients with MCI. This association was profound only in APOE ε4carriers.

We propose and analyze a compact polarizing beam splitter (PBS) based on a metal-insulator-metal (MIM) structure inserted into a multimode interference coupler (MMI). Owing to the MIM structure, the TE polarized state is reflected by the cut-off condition while the TM polarized state is transmitted by the surface plasmon polariton, and the two polarized states can thus be separated. In this paper, the dependence of the reflected TE and transmitted TM field intensities on the MIM length and the gap thickness has been studied systematically. The proposed PBS structure, with a total size of 4 x 0.7 x 44 mu m(3) is designed with MIM length, gap thickness, and metal thickness of 0.6 mu m, 0.5 mu m, and 0.05 mu m, respectively. In the designed PBS, the transmittance for the TM polarized light, reflectance for the TE polarized light, extinction ratio, and insertion losses of the TE and TM modes are obtained using a 3D finite-difference time-domain method to be 0.9, 0.88, 12.55 dB, and 1.1 dB and 0.9 dB, respectively. The designed PBS has a much shorter length, 44 mu m, compared to previous PBS devices. (C) 2013 Optical Society of America