Never-Ending Learning for Explainable Brain Computing

Exploring the nature of human intelligence and behavior is a longstanding pursuit in cognitive neuroscience, driven by the accumulation of knowledge, information, and data across various studies. However, achieving a unified and transparent interpretation of findings presents formidable challenges. In response, an explainable brain computing framework is proposed that employs the never-ending learning paradigm, integrating evidence combination and fusion computing within a Knowledge-Information-Data (KID) architecture. The framework supports continuous brain cognition investigation, utilizing joint knowledge-driven forward inference and data-driven reverse inference, bolstered by the pre-trained language modeling techniques and the human-in-the-loop mechanisms. In particular, it incorporates internal evidence learning through multi-task functional neuroimaging analyses and external evidence learning via topic modeling of published neuroimaging studies, all of which involve human interactions at different stages. Based on two case studies, the intricate uncertainty surrounding brain localization in human reasoning is revealed. The present study also highlights the potential of systematization to advance explainable brain computing, offering a finer-grained understanding of brain activity patterns related to human intelligence.

Demonstration of nuclear gamma-ray polarimetry based on a multi-layer CdTe Compton camera

To detect and track structural changes in atomic nuclei, the systematic study of nuclear levels with firm spin-parity assignments is important. While linear polarization measurements have been applied to determine the electromagnetic character of gamma-ray transitions, the applicable range is strongly limited due to the low efficiency of the detection system. The multi-layer Cadmium-Telluride (CdTe) Compton camera can be a state-of-the-art gamma-ray polarimeter for nuclear spectroscopy with the high position sensitivity and the detection efficiency. We demonstrated the capability to operate this detector as a reliable gamma-ray polarimeter by using polarized 847-keV gamma rays produced by the [Formula: see text]([Formula: see text]) reaction. By combining the experimental data and simulated calculations, the modulation curve for the gamma ray was successfully obtained. A remarkably high polarization sensitivity was achieved, compatible with a reasonable detection efficiency. Based on the obtained results, a possible future gamma-ray polarimetery is discussed.

The effect of nano hydroxyapatite coating implant surfaces on gene expression and osseointegration

BACKGROUND

Hierarchical micro-nano structured topography along with surface chemistry modifications of dental implants have been suggested to positively contribute to the osseointegration process. However, the effect of such surface modifications on the molecular response as well as bone formation rate and quality are still unclear, especially in the early healing period. This study aimed to evaluate the effect of coating a double acid etched (DAE) implant surface with nano-sized (20 nm) hydroxyapatite (Nano) with respect to gene expression, histologic parameters, and nanomechanical properties when compared to DAE control at 1 and 2 weeks after implant placement in a rodent femur model.

MATERIAL AND METHODS

Expression of bone-related genes was determined by qRT-PCR (Col-I, Runx-2, Osx, Opn, Ocn, Alp). Histomorphometric evaluation of bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) within implant threads was performed using photomicrographs after histologic processing. Mechanical properties, reduced elastic modulus and hardness, were determined through nanoindentation.

RESULTS

At 1 week, the Nano group demonstrated significantly higher expression of Col-I and Ocn compared to the DAE group, indicating upregulation of osteoprogenitor and osteoblast differentiation genes. At 2 weeks, Nano surface further exhibited enhanced gene expression of Col-I and Osx in comparison to the DAE surface, suggesting an increased mineralization of the newly formed bone. Nanoindentation analysis revealed that the Nano group presented no significant difference on the ranks of reduced elastic modulus and hardness compared to DAE for both timepoints. Histomorphometric analysis yielded no significant difference in the percentage of BIC and BAFO between the Nano and DAE surfaces at 1 and 2 weeks. However, Nano implants did present a higher mean value, ~50%, of BIC compared to DAE, ~30%, after 2 weeks in vivo.

CONCLUSIONS

While no significant differences were observed in the amount and mechanical properties of newly formed bone, Nano surface positively and significantly increased the expression osteogenic genes compared to DAE surface at early healing periods.

Motor training promotes both synaptic and intrinsic plasticity of layer V pyramidal neurons in the primary motor cortex

Layer V neurons in the primary motor cortex (M1) are important for motor skill learning. Since pretreatment of either CNQX or APV in rat M1 layer V impaired rotor rod learning, we analysed training-induced synaptic plasticity by whole-cell patch-clamp technique in acute brain slices. Rats trained for 1 day showed a decrease in small inhibitory postsynaptic current (mIPSC) frequency and an increase in the paired-pulse ratio of evoked IPSCs, suggesting a transient decrease in presynaptic GABA release in the early phase. Rats trained for 2 days showed an increase in miniature excitatory postsynaptic current (mEPSC) amplitudes/frequency and elevated AMPA/NMDA ratios, suggesting a long-term strengthening of AMPA receptor-mediated excitatory synapses. Importantly, rotor rod performance in trained rats was correlated with the mean mEPSC amplitude and the frequency obtained from that animal. In current-clamp analysis, 1-day-trained rats transiently decreased the current-induced firing rate, while 2-day-trained rats returned to pre-training levels, suggesting dynamic changes in intrinsic properties. Furthermore, western blot analysis of layer V detected decreased phosphorylation of Ser^408-409 in GABA_A receptor β₃ subunits in 1-day-trained rats, and increased phosphorylation of Ser⁸³¹ in AMPA receptor GluA1 subunits in 2-day-trained rats. Finally, live-imaging analysis of Thy1-YFP transgenic mice showed that the training rapidly recruited a substantial number of spines for long-term plasticity in M1 layer V neurons. Taken together, these results indicate that motor training induces complex and diverse plasticity in M1 layer V pyramidal neurons. KEY POINTS: Here we examined motor training-induced synaptic and intrinsic plasticity of layer V pyramidal neurons in the primary motor cortex. The training reduced presynaptic GABA release in the early phase, but strengthened AMPA receptor-mediated excitatory synapses in the later phase: acquired motor performance after training correlated with the strength of excitatory synapses rather than inhibitory synapses. As to the intrinsic property, the training transiently decreased the firing rate in the early phase, but returned to pre-training levels in the later phase. Western blot analysis detected decreased phosphorylation of Ser^408-409 in GABA_A receptor β₃ subunits in the acute phase, and increased phosphorylation of Ser⁸³¹ in AMPA receptor GluA1 subunits in the later phase. Live-imaging analysis of Thy1-YFP transgenic mice showed rapid and long-term spine plasticity in M1 layer V neurons, suggesting training-induced increases in self-entropy per spine.

Reaching Task in Rats: Quantitative Evaluation and Effects of 6-OHDA into the Striatum

In this study, we developed an evaluation method using image analysis for reaching tasks. Using this method, we studied forearm function during the reaching task in rats that received a unilateral injection of 6-OHDA into the striatum. The success ratio of the reaching task reduced to 40.5% seven days after the injection. In addition, significant changes were observed in the pronation angle of the forearm, posture control, and targeting (i.e., the distance between all fingertips and the center of the target pellet). Thus, unilateral injection of 6-OHDA reduces dopaminergic function in the brain and causes deterioration of forearm function and posture control in the reaching task.

A parsimonious laboratory system for the evaluation of rat reaching task: recovery from the massive destruction of motor areas

The rat reaching task is one of the best paradigms from behavioral study of upper limb movements. Rats are trained to reach and grab a pellet by extending their hand through a vertical slit. A few conventional imaging systems specific for the rat reaching task are commercially available with a high installation cost. Based on image analysis of video recordings obtained during the reaching task, we, herewith, developed a new, low-cost laboratory system that can be used for the quantitative analysis of ten basic forearm movements, in contrast to subjective assessments used in previous studies. We quantified images of the pronated and supinated palm and the accuracy and speed of reaching the target. Applying this newly developed method, we compared the forearm movements during the reaching task before and after a massive anatomical lesion of the sensorimotor cortex performed by tissue aspiration. We also wanted to investigate the recovery of upper limb function possibly induced by repeating the task for a relatively short term of a few weeks. In the experiment, 7 injured groups and 3 control groups were used. We found characteristic abnormalities of the forearm movements and a significant recovery in the success rate of grasping the target pellet. The present results demonstrate that our method is straightforward for the quantitative evaluation of forearm movements during the reaching task primarily controlled by the sensorimotor cortex.

Changes in fears and worries related to COVID-19 during the pandemic among current employees in Japan: a 5-month longitudinal study

Objectives

This study investigates and describes the time course of fears and worries about COVID-19 among current employees during this outbreak.

Study design

This was a longitudinal study.

Methods

This study was a part of the Employee Cohort Study in Japan. The study comprised 4120 individuals from February 2019. A baseline survey in March 2020, a 2-month follow-up survey in May 2020, and a 5-month follow-up survey in August 2020 were conducted. Questions surveyed respondents’ global fear and worry and six items related to COVID-19. A mixed model for repeated measures of an analysis of variance was used.

Results

A total of 1421 respondents completed the baseline survey. At 2- and 5-month follow-ups, 1032 and 1181 respondents completed surveys, respectively. Of those, 64 and 33 individuals who were temporarily laid off or on leave were recorded as missing values. Global fear and worry about COVID-19 significantly increased from March to August 2020. Fears of personal or family infection, limiting one's activities and national and local government policies also significantly increased with time. In contrast, fears of lack of knowledge and difficulty of obtaining hygiene products significantly decreased.

Conclusion

To conduct efficient risk communication during a pandemic, knowing the concerns of the populace, providing correct information and a sufficient supply of products, and setting clear guidelines are essential.

Ocular dominance plasticity: Molecular mechanisms revisited

Ocular dominance plasticity (ODP) is a type of cortical plasticity operating in visual cortex of mammals that are endowed with binocular vision based on the competition-driven disparity. Earlier, a molecular mechanism was proposed that catecholamines play an important role in the maintenance of ODP in kittens. Having survived the initial test, the hypothesis was further advanced to identify noradrenaline (NA) as a key factor that regulates ODP in the immature cortex. Later, the ODP-promoting effect of NA is extended to the adult with age-related limitations. Following the enhanced NA availability, the chain events downstream lead to the β-adrenoreceptor-induced cAMP accumulation, which in turn activates the protein kinase A. Eventually, the protein kinase translocates to the cell nucleus to activate cAMP responsive element binding protein (CREB). CREB is a cellular transcription factor that controls the transcription of various genes, underpinning neuronal plasticity and long-term memory. In the advent of molecular genetics in that various types of new tools have become available with relative ease, ODP research has lightly adopted in the rodent model the original concepts and methodologies. Here, after briefly tracing the strategic maturation of our quest, the review moves to the later development of the field, with the emphasis placed around the following issues: (a) Are we testing ODP per se? (b) What does monocular deprivation deprive of the immature cortex? (c) The critical importance of binocular competition, (d) What is the adult plasticity? (e) Excitation-Inhibition balance in local circuits, and (f) Species differences in the animal models.

g Factor of the ^{99}Zr (7/2^{+}) Isomer: Monopole Evolution in the Shape-Coexisting Region

The gyromagnetic factor of the low-lying E=251.96(9)  keV isomeric state of the nucleus ^{99}Zr was measured using the time-dependent perturbed angular distribution technique. This level is assigned a spin and parity of J^{π}=7/2^{+}, with a half-life of T_{1/2}=336(5)  ns. The isomer was produced and spin aligned via the abrasion-fission of a ^{238}U primary beam at RIKEN RIBF. A magnetic moment |μ|=2.31(14)μ_{N} was deduced showing that this isomer is not single particle in nature. A comparison of the experimental values with interacting boson-fermion model IBFM-1 results shows that this state is strongly mixed with a main νd_{5/2} composition. Furthermore, it was found that monopole single-particle evolution changes significantly with the appearance of collective modes, likely due to type-II shell evolution.

Work-related psychosocial factors and metabolic syndrome onset among workers: a systematic review and meta-analysis

BACKGROUND

Work-related psychosocial factors have been associated with metabolic syndrome. However, no systematic reviews or meta-analyses have evaluated this association.

METHODS

A systematic literature search was conducted, using PubMed, Embase, PsycINFO, PsycARTICLES and the Japan Medical Abstracts Society. Eligible studies included those that examined the previously mentioned association; had a longitudinal or prospective cohort design; were conducted among workers; provided sufficient data for calculating odds ratios, relative risks or hazard ratios with 95% confidence intervals; were original articles in English or Japanese; and were published no later than 2016. Study characteristics, exposure and outcome variables and association measures of studies were extracted by the investigators independently.

RESULTS

Among 4,664 identified studies, 8 were eligible for review and meta-analysis. The pooled risk of adverse work-related stress on metabolic syndrome onset was significant and positive (RR = 1.47; 95% CI, 1.22-1.78). Sensitivity analyses limiting only the effects of job strain and shift work also indicated a significant positive relationship (RR = 1.75; 95% CI, 1.09-2.79; and RR = 1.59; 95% CI, 1.00-2.54, P = 0.049 respectively).

CONCLUSION

This study reveals a strong positive association between work-related psychosocial factors and an elevated risk of metabolic syndrome onset. The effects of job strain and shift work on metabolic syndrome appear to be significant.

The functional architectures of addition and subtraction: Network discovery using fMRI and DCM

The neuronal mechanisms underlying arithmetic calculations are not well understood but the differences between mental addition and subtraction could be particularly revealing. Using fMRI and dynamic causal modeling (DCM), this study aimed to identify the distinct neuronal architectures engaged by the cognitive processes of simple addition and subtraction. Our results revealed significantly greater activation during subtraction in regions along the dorsal pathway, including the left inferior frontal gyrus (IFG), middle portion of dorsolateral prefrontal cortex (mDLPFC), and supplementary motor area (SMA), compared with addition. Subsequent analysis of the underlying changes in connectivity - with DCM - revealed a common circuit processing basic (numeric) attributes and the retrieval of arithmetic facts. However, DCM showed that addition was more likely to engage (numeric) retrieval-based circuits in the left hemisphere, while subtraction tended to draw on (magnitude) processing in bilateral parietal cortex, especially the right intraparietal sulcus (IPS). Our findings endorse previous hypotheses about the differences in strategic implementation, dominant hemisphere, and the neuronal circuits underlying addition and subtraction. Moreover, for simple arithmetic, our connectivity results suggest that subtraction calls on more complex processing than addition: auxiliary phonological, visual, and motor processes, for representing numbers, were engaged by subtraction, relative to addition. Hum Brain Mapp 38:3210-3225, 2017. © 2017 Wiley Periodicals, Inc.

Modeling Drug-Induced Neuropathy Using Human iPSCs for Predictive Toxicology

Drugs under development can cause unpredicted toxicity in humans due to differential drug responsiveness between humans and other disease models, resulting in clinical trial failures. Human induced pluripotent stem cells (iPSCs) are expected to represent a useful tool for toxicity testing. However, among many assays, appropriate cellular assays for predicting neurotoxicity in an iPSC-based model are still uncertain. Here we generated neurons from iPSCs of Charcot-Marie-Tooth disease (CMT) patients. Some CMT patients are sensitive to anticancer drugs and present with an adverse reaction of neuropathy. We analyzed cellular phenotypes and found that mitochondria in neurites of CMT neurons were morphologically shorter and showed slower mobility compared to control. A neurosphere assay showed that treatment with drugs known to cause neuropathy caused mitochondrial aggregations in neurites with adenosine triphosphate shortage in both CMT and control neurons, although more severely in CMT. These findings suggest that the genetically susceptible model could provide a useful tool to predict drug-induced neurotoxicity.

Role of mitogen-activated protein kinase pathways in migration of gingival epithelial cells in response to stimulation by cigarette smoke condensate and infection by Porphyromonas gingivalis

BACKGROUND AND OBJECTIVE

Previous studies have shown that cigarette smoke (CS) and periodontal pathogens could alter wound healing responses of gingival epithelial cells. To elucidate molecular mechanisms leading to these epithelial changes, we studied the signaling pathway involved in the modulation of cell migration by CS condensate (CSC) and the infection by a prominent periodontal pathogen, Porphyromonas gingivalis.

MATERIAL AND METHODS

Human gingival epithelial cells (Ca9-22) were treated with CSC or vehicle control for 24 h. Activation of mitogen-activated protein kinases (MAPK) in cells with or without infection by P. gingivalis was assessed by polymerase chain reaction array and immunoblotting using phospho-specific antibodies. Cell migration was assessed using in vitro wound closure model, and specific pharmacologic inhibitors of MAPK pathways were used to characterize further the extent of involvement of the MAPK pathways.

RESULTS

Polymerase chain reaction array showed that gene expression of several members of the MAPK, particularly p38 and JNK, was upregulated more than twofold in Ca9-22 cells stimulated with 10 μg/mL CSC. Coincubation with P. gingivalis induced a different pattern of gene expression for MAPK pathways, but it did not suppress the MAPK-related genes upregulated by CSC. A significant phosphorylation of ERK1/2 and p38 was observed in cells stimulated with 10 μg/mL CSC (p < 0.05), whereas coincubation with a higher concentration of CSC (250 μg/mL) evoked no such activation. P. gingivalis infection resulted in a tendency to reduce the phosphorylation of ERK1/2 and p38, which had been enhanced by stimulation with 10 μg/mL CSC. Incubation with ERK1/2 and p38 inhibitors significantly reduced the wound closure of CSC-stimulated cells, by approximately 43% and 46%, respectively (p < 0.05).

CONCLUSION

CSC exerts effects on the migration of human gingival epithelial cells through the activation of the MAPK ERK1/2 and p38 signaling pathways. P. gingivalis infection attenuates the CSC-induced migration at least partly by suppressing the phosphorylation of ERK1/2 and p38, but other pathways are likely to be involved in this modulatory process.

Task and Resting-State fMRI Reveal Altered Salience Responses to Positive Stimuli in Patients with Major Depressive Disorder

Altered brain function in patients with major depressive disorder (MDD) has been repeatedly demonstrated by task-based and resting-state studies, respectively. However, less is known concerning whether overlapped abnormalities in functional activities across modalities exist in MDD patients. To find out the answer, we implemented an fMRI experiment and collected both task and resting-state data from 19 MDD patients and 19 matched, healthy, controls. A distraction paradigm involving emotionally valenced pictures was applied to induce affective responses in subjects. As a result, concurrent deficits were found in arousing activation during a positive task in both the reward circuit and salience network (SN) that is composed of the dorsal part of anterior cingulate cortex (dACC) and bilateral anterior insulae (AI) in only the MDD group. Subsequent amplitude of low frequency fluctuations (ALFF) and functional connectivity analyses based on resting-state data exhibited consistent alterations in the bilateral AI of MDD patients, and indicated patients' difficulties in regulating the balance between central executive network (CEN) and default mode network (DMN) due to altered connectivity among the CEN, DMN, and SN. Our findings provide new evidence demonstrating impaired salience processing and resulting alterations in responses to positive stimuli in MDD patients. Furthermore, brain abnormalities synchronized across functional states in MDD patients can be evidenced by a combination of task and resting-state fMRI analyses.

Supranormal orientation selectivity of visual neurons in orientation-restricted animals

Altered sensory experience in early life often leads to remarkable adaptations so that humans and animals can make the best use of the available information in a particular environment. By restricting visual input to a limited range of orientations in young animals, this investigation shows that stimulus selectivity, e.g., the sharpness of tuning of single neurons in the primary visual cortex, is modified to match a particular environment. Specifically, neurons tuned to an experienced orientation in orientation-restricted animals show sharper orientation tuning than neurons in normal animals, whereas the opposite was true for neurons tuned to non-experienced orientations. This sharpened tuning appears to be due to elongated receptive fields. Our results demonstrate that restricted sensory experiences can sculpt the supranormal functions of single neurons tailored for a particular environment. The above findings, in addition to the minimal population response to orientations close to the experienced one, agree with the predictions of a sparse coding hypothesis in which information is represented efficiently by a small number of activated neurons. This suggests that early brain areas adopt an efficient strategy for coding information even when animals are raised in a severely limited visual environment where sensory inputs have an unnatural statistical structure.

Evaluation of a novel immunochromatographic device for rapid and accurate clinical detection of Porphyromonas gingivalis in subgingival plaque

An important goal for the improved diagnosis and management of infectious and inflammatory diseases, such as periodontitis, is the development of rapid and accurate technologies for the decentralized detection of bacterial pathogens. The aim of this prospective multicenter study was to evaluate the clinical use of a novel immunochromatographic device with monoclonal antibodies for the rapid point-of-care detection and semi-quantification of Porphyromonas gingivalis in subgingival plaque. Sixty-three patients with chronic periodontitis and 28 periodontally healthy volunteers were subjected to clinical and microbiological examinations. Subgingival plaque samples were analyzed for the presence of P. gingivalis using a novel immunochromatography based device DK13-PG-001, designed to detect the 40k-outer membrane protein of P. gingivalis, and compared with a PCR-Invader method. In the periodontitis group, a significant strong positive correlation in detection results was found between the test device score and the PCR-Invader method (Spearman rank correlation, r=0.737, p<0.0001). The sensitivity, specificity, and positive and negative predictive values of the test device were 96.2%, 91.8%, 90.4% and 96.7%, respectively. The detection threshold of the test device was determined to be approximately 10(4) (per two paper points). There were significant differences in the bacterial counts by the PCR-Invader method among groups with different ranges of device scores. With a cut-off value of ≥0.25 in device score, none of periodontally healthy volunteers were tested positive for the subgingival presence of P. gingivalis, whereas 76% (n=48) of periodontitis subjects were tested positive. There was a significant positive correlation between device scores for P. gingivalis and periodontal parameters including probing pocket depth and clinical attachment level (r=0.317 and 0.281, respectively, p<0.01). The results suggested that the DK13-PG-001 device kit can be effectively used for rapid, chair-side detection and semi-quantification of P. gingivalis in subgingival plaque.

TRIAL REGISTRATION

UMIN Clinical Trials Registry (UMIN-CTR) UMIN000011943.

Does Internet-based cognitive behavioral therapy (iCBT) prevent major depressive episode for workers? A 12-month follow-up of a randomized controlled trial

BACKGROUND

In this study we investigated whether an Internet-based computerized cognitive behavioral therapy (iCBT) program can decrease the risk of DSM-IV-TR major depressive episodes (MDE) during a 12-month follow-up of a randomized controlled trial of Japanese workers.

METHOD

Participants were recruited from one company and three departments of another company. Those participants who did not experience MDE in the past month were randomly allocated to intervention or control groups (n = 381 for each). A 6-week, six-lesson iCBT program was provided to the intervention group. While the control group only received the usual preventive mental health service for the first 6 months, the control group was given a chance to undertake the iCBT program after a 6-month follow-up. The primary outcome was a new onset of DSM-IV-TR MDE during the 12-month follow-up, as assessed by means of the web version of the WHO Composite International Diagnostic Interview (CIDI), version 3.0 depression section.

RESULTS

The intervention group had a significantly lower incidence of MDE at the 12-month follow-up than the control group (Log-rank χ2 = 7.04, p < 0.01). The hazard ratio for the intervention group was 0.22 (95% confidence interval 0.06-0.75), when estimated by the Cox proportional hazard model.

CONCLUSIONS

The present study demonstrates that an iCBT program is effective in preventing MDE in the working population. However, it should be noted that MDE was measured by self-report, while the CIDI can measure the episodes more strictly following DSM-IV criteria.

Cigarette smoke condensate modulates migration of human gingival epithelial cells and their interactions with Porphyromonas gingivalis

BACKGROUND AND OBJECTIVE

Epithelial cells are recognized as the first line of defense against bacterial infection and environmental harmful stimuli such as cigarette smoke (CS). Although previous studies explored the effects of nicotine on host cells, mechanisms by which CS affects cellular functions remain uncertain. The present study investigated the effects of CS condensate (CSC) on in vitro wound closure of gingival epithelial cells and their potential interactions with a major periodontal pathogen, Porphyromonas gingivalis.

MATERIAL AND METHODS

Human gingival epithelial cells (Ca9-22) were treated with CSC for 24 h. Cell proliferation was determined using a WST-1 assay. Cell migration was assessed using a wound closure model. The expression of integrins was analyzed by confocal scanning laser microscopy and real-time PCR. Intracellular invasion of P. gingivalis was evaluated by confocal scanning laser microscopy and an antibiotic protection assay.

RESULTS

Low concentrations (1-10 μg/mL) of CSC showed no significant effect on cell proliferation. CSC demonstrated dual effects on epithelial wound closure of Ca9-22 cells: high concentrations (i.e. 250 μg/mL) significantly inhibited the wound closure whereas low concentrations (i.e. 10 μg/mL) promoted it (p < 0.01). CSC induced distinct changes in cytoskeleton. When CSC-exposed cells were infected with P. gingivalis for 2 h, a significant inhibition of wound closure was observed concurrent with a decrease in integrin α3 expression near the wound area. A significantly increased P. gingivalis invasion into Ca9-22 was observed when exposed to low concentrations of CSC.

CONCLUSION

Low concentrations of CSC increased invasion of human gingival epithelial cells by P. gingivalis and induced changes in cytoskeleton and integrin expression, thereby modulating the cell migration.

Local current density measurement using a Rogowski probe in Tokyo Spherical Tokamak-2

A Rogowski probe consisting of a small multi-layer Rogowski coil, five magnetic pick-up coils, and a Langmuir probe was developed to measure the local current density and its direction. It can be moved along the major radius and can be turned around its axis. This probe was used to measure the current density profile near the last closed flux surface of Ohmic plasmas in Tokyo Spherical Tokamak-2. The current density profile was measured successfully with a signal to noise ratio of greater than 20.

Demonstration of improvement in the signal-to-noise ratio of Thomson scattering signal obtained by using a multi-pass optical cavity on the Tokyo Spherical Tokamak-2

The multi-pass Thomson scattering (TS) scheme enables obtaining many photons by accumulating multiple TS signals. The signal-to-noise ratio (SNR) depends on the accumulation number. In this study, we performed multi-pass TS measurements for ohmically heated plasmas, and the relationship between SNR and the accumulation number was investigated. As a result, improvement of SNR in this experiment indicated similar tendency to that calculated for the background noise dominant situation.

Off-pump coronary artery bypass for a heparin-allergic patient

A 46-year-old man with no history of drug allergy developed acute myocardial infarction. Coronary angiographic findings revealed triple vessel disease. Serum hepatic enzymes were elevated due to heparin administered to control infarction, and an allergic reaction developed exclusively due to heparin. To avoid heparin use, we adopted heparin-free off-pump coronary artery bypass grafting through median sternotomy. The systemic anticoagulant agent argatroban was administered to maintain active clotting time over 200 seconds. The left internal thoracic artery was anastomosed to the left anterior descending artery, the radial artery to the diagonal branch, and the right gastroepiploic artery to the right coronary artery. Patency was confirmed by postoperative coronary angiography. No complications were noted. For patients with heparin allergy, off-pump coronary artery bypass grafting is a useful maneuver, because it can be conducted using anticoagulant agents other than heparin.

Note: Multi-pass Thomson scattering measurement on the TST-2 spherical tokamak

In multi-pass Thomson scattering (TS) scheme, a laser pulse makes multiple round trips through the plasma, and the effective laser energy is enhanced, and we can increase the signal-to-noise ratio as a result. We have developed a coaxial optical cavity in which a laser pulse is confined, and we performed TS measurements using the coaxial cavity in tokamak plasmas for the first time. In the optical cavity, the laser energy attenuation was approximately 30% in each round trip, and we achieved a photon number gain of about 3 compared with that obtained in the first round trip. In addition, the temperature measurement accuracy was improved by accumulating the first three round trip waveforms.

c-Fos activity mapping reveals differential effects of noradrenaline and serotonin depletion on the regulation of ocular dominance plasticity in rats

The roles of the central noradrenergic and serotonergic system in the activity-dependent regulation of ocular dominance plasticity have been a contentious issue. Using c-Fos activity mapping, we have developed a new, straightforward method to measure the strength of ocular dominance plasticity: the number of c-Fos-immunopositive cells in layer IV of rat visual cortex (Oc1B), ipsilateral to the stimulated eye, is a sensitive and reliable measure of the effects of monocular deprivation. Applying this new method, here we studied the unique modification of the degree of c-Fos expression induced in the visual cortex, in that endogenous noradrenaline (NA) and serotonin (5HT) in the cortex were significantly reduced, respectively by specific pharmacological agents. Intraperitoneal injections of N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4) and p-chlorophenylalanine (pCPA) selectively impair NA- and 5HT-containing nerve terminals and fibers, respectively. In the visual cortex with strongly reduced NA, the number of c-Fos-immunopositive cells was found remaining significantly decreased in response to stimulation of the deprived eye, while by open eye stimulation the expected increase in c-Fos-immunoreactivity was strongly suppressed, showing values not different from those obtained by monocular stimulation in the normal rats. In contrast, in the visual cortex with strongly reduced 5HT no expected decrease was found in response to stimulation of the deprived eye, while, as is usually the case for the normal animals, a significant increase was still induced in response to open eye stimulation. These findings suggest that the noradrenergic and serotonergic system regulate ocular dominance (OD) plasticity differently: in the NA-depleted cortex the expected increase in c-Fos expression by open eye stimulation was not seen due to strong suppression, whereas in 5HT-depletion, the expected decrease in c-Fos expression was not materialized due to strong suppression. The present findings with c-Fos activity mapping method indicated a novel possibility of the differential regulation of OD plasticity by two types of common monoaminergic systems.

First demonstration of MC-EDFA-repeatered SDM transmission of 40 x 128-Gbit/s PDM-QPSK signals per core over 6,160-km 7-core MCF

We demonstrate the first 7-core multicore erbium-doped fiber amplified (MC-EDFA) transmission of 40 x 128-Gbit/s PDM-QPSK signals over 6,160-km 7-core multicore fiber (MCF). The crosstalk (XT) from all of the other 6 cores of a MC-EDFA and a 55-km length MCF are about -46.5 dB and -45.6 dB at center core, respectively. The core-to-core rotation approach at every amplified span is used to average the XT of all cores. The averaged optical signal-to-noise ratio (OSNR) after 6,160-km transmission is 15.6 dB with 0.1 nm resolution bandwidth. The Q-factor of all 40 channels surpasses the threshold of the forward-error-correction of 6.4 dB with 1 dB margin after 6,160 km. The total net capacity is 28.8 Tbit/s per fiber and achieved capacity-distance product is 177 Pbit/s.km per fiber. We confirmed the feasibility of MC-EDFA repeatered systems for trans-oceanic transmission.

Cerebral blood flow and freezing of gait in Parkinson's disease

OBJECTIVE

We investigated the relationship between freezing of gait (FOG) severity in Parkinson's disease (PD) and regional cerebral blood flow (rCBF) using single-photon emission computed tomography (SPECT) and evaluated the effect of selegiline therapy.

METHOD

We evaluated 54 patients with PD (FOG positive: 21 patients, and FOG negative: 33 patients) with N-isopropyl-p-[I-123] iodoamphetamine ((123) I-IMP) SPECT and the Unified Parkinson's Disease Rating Scale (UPDRS) part III, Mini-Mental State Examination (MMSE), and Beck Depression Inventory. [Correction added on 18 April 2012, after online publication: In the preceding statement, 55 instead of 54 patients with PD were evaluated, and FOG negative consisted of 34 instead of 33 patients] Furthermore, we examined rCBF in FOG-negative patients treated with levodopa with or without selegiline.

RESULTS

Z-values of bilateral Brodmann areas (BA) 10 and 11 and left BA32 showed significant increases in the FOG-positive group compared with the FOG-negative group. [Correction added on 18 April 2012, after online publication: In the preceding statement, Z-values was changed to Z-scores] There were significantly positive correlations between Z-values of these areas and FOG score, especially on both sides of BA11. [Correction added on 18 April 2012, after online publication: In the preceding statement, Z-values was changed to Z-scores] An increase in Z-values in bilateral BA10 and 11 and left BA32 in the levodopa-selegiline treatment group after 1 year was significantly inhibited compared with the levodopa treatment group. [Correction added on 18 April 2012, after online publication: In the preceding statement, left BA32 was changed to right BA32, and Z-values was changed to Z-scores]

CONCLUSION

There was a close relationship between FOG severity in PD and an increase in rCBF in BA 10, 11 and 32. Furthermore, selegiline's FOG prevention effect may be related to maintaining rCBF in these same areas.

Hemocytes and humoral factors in silkworm blood are cooperatively involved in sheep erythrocyte aggregation

Sheep red blood cells (SRBCs) rapidly aggregated when injected into the blood (hemolymph) of living silkworms. SRBCs also rapidly aggregated when incubated with hemolymph in vitro. SRBCs did not aggregate when incubated with single hemolymph components, hemocytes and cell-free plasma separated by centrifugation, whereas incubation with the mixture of components induced SRBC aggregation, suggesting that both hemocytes and plasma are required for the reaction. Treatment of hemocytes with sodium azide inhibited SRBC aggregation. On the other hand, SRBCs pre-incubated with hemocytes aggregated in the plasma, even in the presence of sodium azide. SRBC aggregation was not observed when the SRBCs were physically separated from the hemocytes by a polycarbonate filter. These findings suggest that SRBCs are directly attacked by hemocytes and become sensitive to humoral factors that cause SRBC aggregation.

An alteration in the lateral geniculate nucleus of experimental glaucoma monkeys: in vivo positron emission tomography imaging of glial activation

We examined lateral geniculate nucleus (LGN) degeneration as an indicator for possible diagnosis of glaucoma in experimental glaucoma monkeys using positron emission tomography (PET). Chronic intraocular pressure (IOP) elevation was induced by laser trabeculoplasty in the left eyes of 5 cynomolgus monkeys. Glial cell activation was detected by PET imaging with [¹¹C]PK11195, a PET ligand for peripheral-type benzodiazepine receptor (PBR), before and at 4 weeks after laser treatment (moderate glaucoma stage). At mild, moderate, and advanced experimental glaucoma stages (classified by histological changes based on the extent of axonal loss), brains were stained with cresyl violet, or antibodies against PBR, Iba-1 (a microglial marker), and GFAP (an activated astrocyte marker). In laser-treated eyes, IOP was persistently elevated throughout all observation periods. PET imaging showed increased [¹¹C]PK11195 binding potential in the bilateral LGN at 4 weeks after laser treatment; the increase in the ipsilateral LGN was statistically significant (P<0.05, n = 4). Immunostaining showed bilateral activations of microglia and astrocytes in LGN layers receiving input from the laser-treated eye. PBR-positive cells were observed in LGN layers receiving input from laser-treated eye at all experimental glaucoma stages including the mild glaucoma stage and their localization coincided with Iba-1 positive microglia and GFAP-positive astrocytes. These data suggest that glial activation occurs in the LGN at a mild glaucoma stage, and that the LGN degeneration could be detected by a PET imaging with [¹¹C]PK11195 during the moderate experimental glaucoma stage after unilateral ocular hypertension. Therefore, activated glial markers such as PBR in the LGN may be useful in noninvasive molecular imaging for diagnosis of glaucoma.

Transforming growth factor β1 T868C gene polymorphism is associated with cerebral infarction in Japanese patients with type 2 diabetes

It is likely that the C allele of the polymorphism at position 29 of the translated sequence of transforming growth factor (TGF)-β1 gene, which codes a pleiotropic cytokine expressed in a variety of cells, is a susceptibility allele for cerebral infarction in Japanese type 2 diabetic patients.

A 2.4 GHz ULP OOK Single-Chip Transceiver for Healthcare Applications

This paper describes an ultra-low power (ULP) single chip transceiver for wireless body area network (WBAN) applications. It supports on-off keying (OOK) modulation, and it operates in the 2.36-2.4 GHz medical BAN and 2.4-2.485 GHz ISM bands. It is implemented in 90 nm CMOS technology. The direct modulated transmitter transmits OOK signal with 0 dBm peak power, and it consumes 2.59 mW with 50% OOK. The transmitter front-end supports up to 10 Mbps. The transmitter digital baseband enables digital pulse-shaping to improve spectrum efficiency. The super-regenerative receiver front-end supports up to 5 Mbps with -75 dBm sensitivity. Including the digital part, the receiver consumes 715 μW at 1 Mbps data rate, oversampled at 3 MHz. At the system level the transceiver achieves PER=10 (-2) at 25 meters line of site with 62.5 kbps data rate and 288 bits packet size. The transceiver is integrated in an electrocardiogram (ECG) necklace to monitor the heart's electrical property.

The relationship between depression and regional cerebral blood flow in Parkinson's disease and the effect of selegiline treatment

OBJECTIVES

We examined the relationship between severity of depression in Parkinson's disease (PD) and regional cerebral blood flow (rCBF) using single photon emission computed tomography (SPECT) and the reaction to levodopa-selegiline combination therapy.

MATERIALS AND METHODS

We evaluated 52 patients with PD and nine age-matched controls with SPECT and the Unified Parkinson's Disease Rating Scale (UPDRS) part III, Mini-Mental State Examination (MMSE), and Beck Depression Inventory (BDI) to evaluate depression severity and its connection with rCBF. Furthermore, we examined rCBF in patients with PD treated with levodopa with or without selegiline.

RESULTS

A significant fall in rCBF was observed in the bilateral posterior cingulate, hippocampus, and cuneus and the superior parietal and primary visual areas in PD patients with minor depression and in all regions in those with major depression. Elevations in UPDRS part III and BDI scores and falls in MMSE scores were of significantly lower magnitude in the levodopa-selegiline group than in the levodopa group. Whole brain rCBF fell significantly less in the levodopa-selegiline group than in the levodopa group.

CONCLUSIONS

These results indicate that selegiline controlled not only worsening of motor function and cognitive function in PD but also aggravation of minor depression, and restrained a fall in whole brain rCBF.

Aldose reductase C-106T gene polymorphism is associated with diabetic retinopathy in Japanese patients with type 2 diabetes

It is likely that the C allele of the polymorphism at position -106 in the promoter of aldose reductase gene, which codes a rate-limiting enzyme of the polyol pathway, is a susceptibility allele for diabetic retinopathy in Japanese type 2 diabetic patients.

Involvement of endoplasmic reticulum stress on neuronal cell death in the lateral geniculate nucleus in the monkey glaucoma model

We investigated whether endoplasmic reticulum (ER) stress was involved in the pathophysiological mechanisms underlying neuronal death of the lateral geniculate nucleus (LGN) after intraocular pressure (IOP) elevation. Five cynomolgus monkeys, four with a glaucomatous left eye after laser photocoagulation treatment and one normal monkey, were studied. At 4, 11, 15 and 24 weeks after the laser photocoagulation treatment, the numbers of LGN neurons and atrophy were immunohistochemically evaluated using anti-parvalbumin-antibody, which was used to specifically label relay neurons connecting to the visual cortex. In addition, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cells, polyubiquitin, and production of ER stress-related proteins, such as the phosphorylation of eukaryotic initiation factor 2α (p-eIF2α) and C/EBP-homologous protein (CHOP), were also measured using in situ hybridization and immunostaining. Loss of neurons and/or neuronal atrophy in layers 1, 4 and 6 of the LGN on the contralateral side were observed at 4-24 weeks after the laser photocoagulation treatment. Furthermore, the retinal input from the high IOP eye projected to layers 2 (magnocellular layer), 3 and 5 (parvocellular layer) on the ipsilateral side. Neuronal damage was also confirmed in these layers. In the LGN region, TUNEL-positive cells, polyubiquitin, p-eIF2α and CHOP were also detected at 11-24 weeks after the laser photocoagulation treatment. These findings indicate that ER stress may play a pivotal role in neuronal death of the LGN after IOP elevation.

Evaluation of therapeutic effects and pharmacokinetics of antibacterial chromogenic agents in a silkworm model of Staphylococcus aureus infection

The therapeutic effect of dye compounds with antibacterial activity was evaluated in a silkworm model of Staphylococcus aureus infection. Among 13 chromogenic agents that show antibacterial activity against S. aureus (MIC = 0.02 to 19 μg/mL), rifampicin had a therapeutic effect. The ED(50) value in the silkworm model was consistent with that in a murine model. Other 12 dyes did not increase survival of the infected silkworms. We examined the reason for the lack of therapeutic efficacy. Amidol, pyronin G, and safranin were toxic to silkworms, which explained the lack of therapeutic effects. Fuchsin basic and methyl green disappeared quickly from the hemolymph after injection, suggesting that they are not stable in the hemolymph. Although coomassie brilliant blue R250/G250, cresyl blue, and nigrosin showed no toxic effects or instability in the hemolymph, they also did not have a therapeutic effect. The in vitro antibacterial actions of these dyes were inhibited by silkworm plasma or bovine serum albumin and filtration experiments demonstrated that cresyl blue bound to plasma proteins in the silkworm, suggesting that plasma protein binding inhibited the therapeutic efficacy of these four dyes. These findings indicate that drug screening using the silkworm infection model is useful for evaluating toxicity and pharmacokinetics of potential antibiotics.

Cortical activation during color discrimination task in macaques as revealed by positron emission tomography

Physiological and lesion studies have shown that the anterior inferior temporal (IT) cortex (aITC) is involved in the color vision of macaque monkeys. However, some functional imaging studies using awake monkeys contradicted the involvement of aITC in color vision. Thus, in most of the imaging studies, cortical activation has been observed during a fixation task. However, because the neuronal activity of aITC is highly affected by the behavioral task, it is desirable to investigate cortical activity during a color discrimination task to determine the functional role of aITC in the color vision of macaque monkeys. In this study, we investigated the cortical activity of aITC of macaque monkeys during color discrimination by positron emission tomography. Two monkeys were trained in a color discrimination task. Cortical areas involved in color processing were investigated by comparing activities during the color discrimination and lever release tasks. In addition to area V4 and the posterior IT cortex (pITC), we found color-related activities in the anterior IT gyrus. Consistent activation was observed in the region posterior to the anterior medial temporal sulcus (AMTS), although the exact location and the size of activations differed between monkeys and hemispheres. We also found color-related activities in the anterior portion of the superior temporal sulcus (STS), suggesting its involvement in the color vision. The present results revealed that aITC is involved in the color vision of macaque monkeys by a functional imaging technique.