Utility of bronchoscopically obtained frozen cytology pellets for next-generation sequencing.

BACKGROUND: Next-generation sequencing (NGS) is essential for lung cancer treatment. It is important to collect sufficient tissue specimens, but sometimes we cannot obtain large enough samples for NGS analysis. We investigated the yield of NGS analysis by frozen cytology pellets using an Oncomine Comprehensive Assay or Oncomine Precision Assay. METHODS: We retrospectively enrolled patients with lung cancer who underwent bronchoscopy at Kobe University Hospital and were enrolled in the Lung Cancer Genomic Screening Project for Individualized Medicine. We investigated the amount of extracted DNA and RNA and determined the NGS success rates. We also compared the amount of DNA and RNA by bronchoscopy methods. To create the frozen cytology pellets, we first effectively collected the cells and then quickly centrifuged and cryopreserved them. RESULTS: A total of 132 patients were enrolled in this study between May 2016 and December 2022; of them, 75 were subjected to frozen cytology pellet examinations and 57 were subjected to frozen tissue examinations. The amount of DNA and RNA obtained by frozen cytology pellets was nearly equivalent to frozen tissues. Frozen cytology pellets collected by endobronchial ultrasound-guided transbronchial needle aspiration yielded significantly more DNA than those collected by transbronchial biopsy methods. (P < 0.01) In RNA content, cytology pellets were not inferior to frozen tissue. The success rate of NGS analysis with frozen cytology pellet specimens was comparable to the success rate of NGS analysis with frozen tissue specimens. CONCLUSIONS: Our study showed that frozen cytology pellets may have equivalent diagnostic value to frozen tissue for NGS analyses. Bronchial cytology specimens are usually used only for cytology, but NGS analysis is possible if enough cells are collected to create pellet specimens. In particular, the frozen cytology pellets obtained by endobronchial ultrasound-guided transbronchial needle aspiration yielded sufficient amounts of DNA. TRIAL REGISTRATION: This was registered with the University Medical Hospital Information Network in Japan (UMINCTR registration no. UMIN000052050).

Impact of concurrent medications on the outcome of immunotherapy in non-small cell lung carcinoma.

BACKGROUND: There have been reports on the impact of concurrent drugs on the outcome of immunotherapy for non-small cell lung carcinoma (NSCLC). However, the effect of some drugs, such as antibiotics and nonsteroidal anti-inflammatory drugs (NSAIDs), has not been clarified in patients with NSCLC. In the present study, we aimed to assess the association between concurrent drugs and the outcomes of immune checkpoint inhibitors (ICIs) alone or in combination with chemotherapy for patients with advanced NSCLC. METHODS: We retrospectively assessed patients with advanced NSCLC who underwent ICI treatment between September 2017 and December 2021 at Kobe University Hospital. We evaluated the data regarding the use of antibiotics within 30 days before ICI initiation, as well as the use of proton pump inhibitors (PPIs) and NSAIDs during ICI initiation. RESULTS: A total of 127 patients were assessed, among whom 28 (22.0%) patients received antibiotics, 39 (30.7%) PPIs, and 36 (28.3%) NSAIDs. No significant differences were observed between the patients with and without antibiotic use. However, patients using NSAIDs had significantly worse objective response rates (ORR) and progression-free survival (PFS) with ICI alone or in combination with chemotherapy compared to those who did not (ORR, 47.2% vs. 67.0%; p = 0.045. PFS, 6.3 months vs. 10.8 months; p = 0.02). Patients using PPIs demonstrated a worse ORR of ICI in combination with chemotherapy compared to those who did not (ORR, 45.2% vs. 72.6%; p = 0.013). CONCLUSIONS: The unnecessary use of NSAIDs along with immunotherapy should be discouraged.

Mechanism of action of adapalene for treating EGFR-TKI-induced skin disorder.

BACKGROUND: Skin disorders are the most common side effect associated with epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) therapy. It is important to manage skin lesions. Adapalene has been used to treat skin lesions caused by EGFR-TKIs in some cases. The aim of this study was to investigate the functional mechanism of adapalene in erlotinib-induced skin disorder. METHODS: To analyze the effect of adapalene on skin rash, afatinib and adapalene were administered to mice. The relationship between the concentration of adapalene and skin disorders was also examined by analyzing AQP3 expression. A skin lesion model was experimentally established in human skin keratinocytes (HaCaT) by using erlotinib with TNF-α and IL-1ß. We used qRT-PCR to analyze chemokine-induced inflammation and western blotting to analyze the effects of adapalene on the NF-κB signaling pathway. Antimicrobial peptides and adhesion factors were also examined using qRT-PCR. RESULTS: Mice administered 0.01% adapalene had less skin inflammation than mice treated with afatinib alone. The expression level of AQP3 decreased in an adapalene concentration-dependent manner. The mRNA levels of proinflammatory cytokines such as CCL2 and CCL27 in HaCaT cells were significantly reduced by adapalene. The expression of an antimicrobial peptide, hBD3, was upregulated after adapalene treatment. Adhesion factors, such as E-cadherin, were significantly downregulated by EGFR-TKI and significantly upregulated by adapalene treatment. Western blot analysis suggested that erlotinib-induced phosphorylation of p65 was decreased by adapalene. CONCLUSION: We suggest that adapalene may be a possible treatment option for skin disorders induced by EGFR-TKIs.

Device parameter to evaluate exciton energy transfer in organic whispering-gallery-mode microresonators and its dependence on the amplified spontaneous emission threshold.

Exciton energy transfer in organic whispering-gallery-mode (WGM) resonators and its effect on the amplified spontaneous emission (ASE) threshold have been investigated using the stilbene-based energy donor 4,4'-bis[(N-carbazole)styryl]biphenyl (BSB-Cz) and the coumarin-based energy acceptor 2,3,6,7-tetrahydro-1,1,7,7,-tetramethyl-1H,5H,11H-10-(2-benzothiazolyl)quinolizino[9,9a,1gh]coumarin (C545T). Using the stacked-layer structure of BSB-Cz/C545T/BSB-Cz, we fabricated bowl-shaped microresonators on silica microspheres with a total thickness of 250 nm fixing the thickness of the C545T layer to 1 nm. The ASE threshold depended on the thicknesses of the top and bottom BSB-Cz layers, which affect the magnitude of the energy transfer. To assess the relationship between the ASE threshold and energy transfer, we developed a device parameter to evaluate the magnitude of the energy transfer by formulating the rate equations. We found that ASE easily occurs under the condition that the C545T molecules become unable to accept energy from the BSB-Cz excitons owing to the high exciton density of C545T, and that the ASE threshold decreases with decreasing device parameter. The device parameter is useful for optimizing microresonator structures in multi-component organic WGM resonators that utilize energy transfer.

Diagnostic yield and the number of tumor cells of ultrathin bronchoscopy for peripheral lung lesions: A comparison with thin bronchoscopy.

Ultrathin bronchoscopy has been reported to have a higher diagnostic yield than thin bronchoscopy for small peripheral lung lesions in transbronchial biopsy under radial endobronchial ultrasonography (EBUS). However, data comparing the number of tumor cells in non-small cell lung cancer (NSCLC) are limited. We retrospectively compared the number of NSCLC tumor cells in peripheral lung lesions obtained using an ultrathin bronchoscope and a thin bronchoscope with radial EBUS between April 2020 and October 2021. In all patients, we used virtual bronchoscopic navigation (VBN) software, and guide sheaths were used in thin bronchoscopy cases. A total of 175 patients were enrolled in this study. Ultrathin bronchoscopy cases (n = 69) had lesions with a smaller diameter that are more peripherally located compared to thin bronchoscopy cases (n = 106) (median, 25.0 vs. 26.5 mm, mean bronchial generations accessed by bronchoscopy; 4.4±1.2 vs. 3.8±1.0, respectively; p<0.010). There were no significant differences in the overall diagnostic yield (ultrathin vs. thin bronchoscopy cases, 68.1% vs. 72.6%, p = 0.610) or diagnostic yield in only lung cancer cases (78.6% vs. 78.5%, p = 1.000). In histologically NSCLC cases (n = 102), the maximum number of tumor cells per slide as the primary endpoint was similar (average, 307.6±246.7 vs. 328.7±314.9, p = 0.710). The success rate of the Oncomine™ analysis did not differ significantly (80.0% vs. 55.6%, p = 0.247). The yield of NSCLC tumor cells was not different between the samples obtained by the ultrathin bronchoscope and those obtained by the thin bronchoscope.

Altered regulation of oligodendrocytes associated with parvalbumin neurons in the ventral hippocampus underlies fear generalization in male mice.

Fear generalization is a neurobiological process by which an organism interprets a novel stimulus as threatening because of its similarity to previously learned fear-inducing stimuli. Because recent studies have suggested that the communication between oligodendrocyte precursor cells (OPCs) and parvalbumin (PV)-expressing GABAergic neurons (PV neurons) may play critical roles in stress-related disorders, we examined the involvement of these cells in fear generalization. We first tested the behavioral characteristics of mouse models for conventional fear conditioning (cFC) and modified FC (mFC) with severe electric foot shocks and found that fear generalization was observed in mice treated with mFC but not in mice treated with cFC. The expression levels of genes related to OPCs, oligodendrocytes (OLs), and myelin in the ventral hippocampus were lower in mFC mice than in cFC mice. The densities of OPCs and OLs were decreased in the ventral hippocampus of mFC mice compared to cFC mice. The myelination ratios of PV neurons in the ventral hippocampus were lower in mFC mice than in cFC mice. The chemogenetic activation of PV neurons in the ventral hippocampus of mFC mice reduced fear generalization. The expression levels of genes related to OPCs, OLs, and myelin were recovered following the activation of PV neurons. Finally, the myelination ratios of PV neurons were increased after the activation of PV neurons. Our results suggest that altered regulation of OLs specifically associated with axons of PV neurons in the ventral hippocampus may underlie the generalization of remote fear memory following severe stress exposure.

In-hospital Mortality among Patients with High-flow Nasal Cannulas in the General Ward.

High-flow nasal cannulas (HFNCs) have become common devices for patients with respiratory failure who are treated in general wards. Few reports have been published on in-hospital mortality associated with the ratio of oxygen saturation (ROX) index, measured by pulse oximetry/fraction of inspired oxygen to respiratory rate, in patients treated with HFNCs. We aimed to examine in-hospital mortality and associated factors in patients who initiated HFNC use in a general ward. Sixty patients who initiated HFNC use in general wards at Kobe University Hospital between December 2016 and October 2020 were retrospectively enrolled. We assessed in-hospital mortality, comorbidities, and ROX index. The in-hospital mortality was 48.3%, and ROX index values were significantly lower in patients who died than in those who did not (at HFNC oxygen therapy initiation; 6.93 [2.73-18.5] vs. 9.01 [4.62-18.1], p = 0.00861). Although the difference was not statistically significant, the change in ROX index values between HFNC initiation and 12 hours after initiation tended to be greater in the patients who died in the hospital (0.732 [-2.84-3.5] vs. -0.35[-4.3-2.6], p = 0.0536). Lower ROX index values may be associated with the in-hospital death of patients who are treated with HFNCs in general wards.

Quiescent innate and adaptive immune responses maintain the long-term integrity of corneal endothelium reconstituted through allogeneic cell injection therapy.

This study aims to clarify the immunogenicity in acquired and innate immune responses of cultured human corneal endothelial cells (hCECs) applied for cell injection therapy, a newly established modality for corneal endothelium failures. Thirty-four patients with corneal endothelial failure received injection of allogeneic hCEC suspension into anterior chamber. No sign of immunological rejection was observed in all 34 patients during the 5-8 years postoperative follow-up period. Cell injection therapy was successful in 2 patients treated for endothelial failure after penetrating keratoplasty and one patient with Descemet membrane stripping automated endothelial keratoplasty failure. ELISPOT assays performed in allo-mixed lymphocyte reaction to the alloantigen identical to that on the injected hCECs, elicited sparse IFN-γ-specific spots in the peripheral blood mononuclear cells of patients who received hCEC injection. The therapy generated simple and smooth graft-host junctions without wound stress. The injection of C57BL/6 CECs into the anterior chamber of BALB/c mice, which rejected C57BL/6 corneas 6 weeks ago, induced no sign of inflammatory reactions after the second challenge of alloantigen. Collectively, injection of the hCEC cell suspension in the aqueous humor induces immune tolerance that contributes to the survival of the reconstituted endothelium.

The utility of bispectral index monitoring in flexible bronchoscopy: A single-center, retrospective observational study.

BACKGROUND: The desired depth of sedation during flexible bronchoscopy is one in which verbal contact is possible whenever necessary. Although it is common that the depth of sedation is assessed by validated instruments such as the modified observer's assessment of alertness and sedation (MOAA/S) score, the repeated stimulation associated with the assessment can affect the sedation. The bispectral index (BIS) has been widely used for general anesthesia due to its objective and noninvasive nature. However, the utility of BIS monitoring and a target BIS value for use during bronchoscopy have not been fully elucidated. METHODS: We performed a retrospective observational study to assess the utility of the BIS value for monitoring conscious sedation during bronchoscopy at Kobe University Hospital from August 2020 to April 2021. RESULTS: Eighteen patients underwent bronchoscopy with BIS monitoring. The BIS value significantly correlated with the MOAA/S score (r = 0.2, p < 0.01), and the correlation was stronger in sufficiently sedated patients (r = 0.486, p < 0.01). The lowest MOAA/S score during the procedure was highly correlated with the BIS value (r = 0.625, p < 0.01). The BIS monitoring seemed to be more sensitive to changes in the sedation level than the MOAA/S score, heart rate and mean arterial pressure. The median BIS value at an MOAA/S score of 3-4, the desired depth of sedation, was 82.0. CONCLUSIONS: BIS value is useful for monitoring sedation during bronchoscopy. This study suggests that a BIS value of 82 reflects an adequate level of sedation.

Chondroitin sulfate proteoglycan is a potential target of memantine to improve cognitive function via the promotion of adult neurogenesis.

BACKGROUND AND PURPOSE: Chondroitin sulfate proteoglycan (CSPG) constitutes the neurogenic niche in the hippocampus. The reduction of hippocampal neurogenesis is involved in ageing-related cognitive decline and dementia. The purpose of this study is to find candidates that improve cognitive function by analysing the effects of memantine (MEM), a therapeutic agent for Alzheimer's disease, on CSPG and adult hippocampal neurogenesis. EXPERIMENTAL APPROACH: The effects of MEM on neurogenesis-related cells and CSPG content were assessed in the hippocampus of middle-aged mice. The MEM-induced alterations in gene expressions of neurotrophins and enzymes associated with biosynthesis and degradation of CSPG in the hippocampus also were measured. The effects of MEM on cognitive function were estimated using a behavioural test battery. The same set of behavioural tests was applied to evaluate the effects of pharmacological depletion of CSPG in the hippocampus. KEY RESULTS: The densities of newborn granule cells and content of CSPG in the hippocampus were increased by MEM. The expression levels of the enzyme responsible for the biosynthesis CSPG were increased by MEM. The neurotrophin-related molecules were activated by MEM. Short- and long-term memory performance was improved by MEM. Pharmacological depletion of CSPG impairs the effects of MEM on cognitive improvement in middle-aged mice. CONCLUSION AND IMPLICATIONS: MEM regulates the biosynthesis and degradation of CSPG, which may underlie the improvement of cognitive function via the promotion of adult hippocampal neurogenesis. These results imply that CSPG-related enzymes potentially may be attractive candidates for the treatment of ageing-related cognitive decline.

Alleviation of cognitive deficits via upregulation of chondroitin sulfate biosynthesis by lignan sesamin in a mouse model of neuroinflammation.

Lignans are plant-derived compounds that act as partial estrogen agonists. Chondroitin sulfate proteoglycans (CSPGs) represent one of the major components of the extracellular matrix. Here we aimed to understand the role of sesamin (SES), a major lignan compound, in the biosynthesis and degradation of CSPGs in the mouse hippocampus because CSPGs play a key role in the regulation of cognitive functions through the promotion of adult neurogenesis. The expression of the pro-inflammatory cytokine interleukin-1ß was decreased by SES administration in the hippocampus of lipopolysaccharide (LPS)-treated mice, a model of neuroinflammation-induced cognitive deficits. The expression of genes related to biosynthesis and degradation of CSPGs in the hippocampus of LPS-treated mice was both increased and decreased by SES administration. Further, the diffuse extracellular matrix labeling of CSPGs by Wisteria floribunda agglutinin (WFA) in the hippocampus of LPS-treated mice was increased by SES administration. The densities of neural stem cells, late transit-amplifying cells, and newborn-granule cells in the hippocampus of LPS-treated mice were also increased by SES administration. Moreover, SES-induced alterations in gene expression, WFA labeling, and adult neurogenesis in LPS-treated mice were more evident in the dorsal hippocampus (center of cognition) than in the ventral hippocampus (center of emotion). Neither LPS nor SES administration affected locomotor activity, anxiety-like behavior, and depression-related behavior. However, impairments in contextual memory and sensorimotor gating in LPS-treated mice were recovered by SES administration. Our results show that SES can promote adult hippocampal neurogenesis through the upregulation of CSPGs, which may alleviate cognitive deficits induced by neuroinflammation.

A simple adaptive difference algorithm with CO2 measurements for evaluating plant growth under environmental fluctuations.

OBJECTIVE: The aim of this study is to demonstrate an adaptive method that is robust toward environmental fluctuations and provides a real-time measure of plant growth by measuring CO2 consumption. To verify the validity of the proposed method, the relation between the plant growth and variation in light conditions with a closed experimental system was investigated. RESULTS: The proposed method was used to measure the photosynthetic rate induced by photosynthetic photon flux density (PPFD) and to evaluate plant growth under continuous and pulsed light in arugula plants. The PPFD-dependent change in photosynthetic rate was measured. And in the condition range of 200-10,000 µs pulse period and 50% duty ratio of pulsed light, there was no change in the growth rate of plants assuming the same PPFD as continuous light. These experiments showed the validity of the adaptive method in removing environmental fluctuations without precise control of temperature and humidity.

Phytoestrogen genistein modulates neuron-microglia signaling in a mouse model of chronic social defeat stress.

Microglia, resident immune cells in the brain, are shown to mediate the crosstalk between psychological stress and depression. Interestingly, increasing evidence indicates that sex hormones, particularly estrogen, are involved in the regulation of immune system. In this study, we aimed to understand the potential effects of chronic social defeat stress (CSDS) and genistein (GEN), an estrogenic compound of the plant origin, on neuron-microglia interactions in the mouse hippocampus. The time spent in the avoidance zone in the social interaction test was increased by CSDS 1 day after the exposure, while the avoidance behavior returned to control levels 14 days after the CSDS exposure. Similar results were obtained from the elevated plus-maze test. However, the immobility time in the forced swim test was increased by CSDS 14 days after the exposure, and the depression-related behavior was in part alleviated by GEN. The numerical densities of microglia in the hippocampus were increased by CSDS, and they were decreased by GEN. The voxel densities of synaptic structures and synaptic puncta colocalized with microglia were decreased by CSDS, and they were increased by GEN. Neither CSDS nor GEN affected the gene expressions of major pro-inflammatory cytokines. Conversely, the expression levels of genes related to neurotrophic factors were decreased by CSDS, and they were partially reversed by GEN. These findings show that GEN may in part alleviate stress-related symptoms, and the effects of GEN may be associated with the modulation of neuron-microglia signaling via chemokines and neurotrophic factors in the hippocampus.

Demonstration of laser biospeckle method for speedy in vivo evaluation of plant-sound interactions with arugula.

In recent years, it is becoming clearer that plant growth and its yield are affected by sound with certain sounds, such as seedling of corn directing itself toward the sound source and its ability to distinguish stuttering of larvae from other sounds. However, methods investigating the effects of sound on plants either take a long time or are destructive. Here, we propose using laser biospeckle, a non-destructive and non-contact technique, to investigate the activities of an arugula plant for sounds of different frequencies, namely, 0 Hz or control, 100 Hz, 1 kHz, 10 kHz, including rock and classical music. Laser biospeckles are generated when scattered light from biological tissues interfere, and the intensities of such speckles change in time, and these changes reflect changes in the scattering structures within the biological tissue. A leaf was illuminated by light from a laser light of wavelength 635 nm, and the biospeckles were recorded as a movie by a CMOS camera for 20 sec at 15 frames per second (fps). The temporal correlation between the frames was characterized by a parameter called biospeckle activity (BA)under the exposure to different sound stimuli of classical and rock music and single-frequency sound stimuli for 1min. There was a clear difference in BA between the control and other frequencies with BA for 100 Hz being closer to control, while at higher frequencies, BA was much lower, indicating a dependence of the activity on the frequency. As BA is related to changes from both the surface as well as from the internal structures of the leaf, LSM (laser scanning microscope) observations conducted to confirm the change in the internal structure revealed more than 5% transient change in stomatal size following exposure to one minute to high frequency sound of 10kHz that reverted within ten minutes. Our results demonstrate the potential of laser biospeckle to speedily monitor in vivo response of plants to sound stimuli and thus could be a possible screening tool for selecting appropriate frequency sounds to enhance or delay the activity of plants. (337 words).

A unique subtype of ramified microglia associated with synapses in the rat hippocampus.

To date, a number of studies have reported the heterogeneity of activated microglia. However, there is increasing evidence suggests that ramified, so-called resting, microglia may also be heterogeneous, and they may play diverse roles in normal brain homeostasis. Here, we found that both 5D4 keratan sulfate epitope-positive (5D4+ ) and 5D4-negative (5D4- ) microglia coexisted in the hippocampus of normal rats, while all microglia were negative for the 5D4 epitope in the hippocampus of normal mice. We thus aimed to determine the potential heterogeneity of microglia related to the 5D4 epitope in the normal rat hippocampus. The optical disector analysis showed that the densities of 5D4+ microglia were higher in the stratum oriens of the CA3 region than in other layers and regions. Although both 5D4+ and 5D4- microglia exhibited a ramified morphology, the three-dimensional reconstruction analysis showed that the node numbers, end numbers, and complexity of processes were higher in 5D4+ than in 5D4- microglia. The linear discriminant analysis showed that 5D4+ and 5D4- microglia can be classified into distinct morphometric subtypes. The ratios of contact between synaptic boutons and microglial processes were higher in 5D4+ than in 5D4- microglia. The gene expressions of pro-inflammatory cytokine interleukin-1ß and purinergic receptor P2Y12 (P2Y12 R) were higher in 5D4+ than in 5D4- microglia. Together, these results indicate that at least two different subtypes of ramified microglia coexist in the normal rat hippocampus and also suggest that 5D4+ microglia may represent a unique subtype associated with synapses.

Chiral metal down to 4.2 K - a BDH-TTP radical-cation salt with spiroboronate anion B(2-chloromandelate)2.

We report the first example of a chiral BDH-TTP radical-cation salt. Chirality is induced in the structure via the use of a chiral spiroboronate anion where three stereocentres are present, one on each chiral ligand and one on the boron centre. Despite starting from a labile racemic mixture of BS and BR enantiomers, only one enantiomer is present in the crystal lattice. The anions pack in a novel double anion layer which is the thickest anion layer found in a BDH-TTP salt. This material is chiral and shows metallic behaviour down to at least 4.2 K.

Malignant pleural mesothelioma in a patient with pneumothorax: A cumbersome subtype both clinically and pathologically.

Here, we report a case of malignant pleural mesothelioma (MPM) that was very difficult to diagnose. A 62-year-old woman with a surgical history of recurrent bilateral pneumothorax was admitted to our hospital with severe dysphagia. Computed tomography (CT) detected stenosis in the lower esophagus. Immunohistochemical examination of a biopsy sample from the stenotic region was suggestive of MPM. Chemotherapy was initiated, but the patient soon weakened and died. Autopsy revealed atypical cells, identical to those seen in the biopsy sample which had spread into the stenotic esophagus and entire thoracic cavity. Although neither pleural thickening/nodules nor asbestos bodies were observed, we finally diagnosed the tumor as a biphasic-type MPM. We re-examined previous surgical specimens of pneumothorax and acknowledged foci of bland mesothelial cell proliferation which had the same pathological findings as tumor cells at autopsy. The lack of asbestos exposure and pleural thickening, an initial manifestation of pneumothorax, and faint cytological atypia prevented an early diagnosis. In cases of recurrent pneumothorax in elderly patients, MPM should be included in the differential diagnosis.

Subclass imbalance of parvalbumin-expressing GABAergic neurons in the hippocampus of a mouse ketamine model for schizophrenia, with reference to perineuronal nets.

Impairments of parvalbumin-expressing GABAergic neurons (PV+ neurons) and specialized extracellular structures called perineuronal nets (PNNs) have been found in schizophrenic patients. In this study, we examined potential alterations in four subclasses of PV+ neurons colocalized with PNNs in the hippocampus of a mouse ketamine model for schizophrenia. Because biosynthesis of human natural killer-1 (HNK-1) is shown to be associated with the risk of schizophrenia, here we used mouse monoclonal Cat-315 antibody, which recognizes HNK-1 glycans on PNNs. Once-daily intraperitoneal injections of ketamine for seven consecutive days induced hyper-locomotor activity in the open field tests. The prepulse inhibition (PPI) test showed that PPI scores declined in ketamine-treated mice compared to vehicle-treated mice. The densities of PV+ neurons and Cat-315+ PNNs declined in the CA1 region of ketamine-treated mice. Interestingly, the density of Cat-315+/PV+ neurons was lower in ketamine-treated mice than in vehicle-treated mice, whereas the density of Cat-315-/PV+ neurons was not affected by ketamine. Among the four subclasses of PV+ neurons, the densities of Cat-315+/PV+ basket cells and Cat-315-/PV+ axo-axonic cells were lower in ketamine-treated mice than in vehicle-treated mice, while the densities of Cat-315-/PV+ basket cells and Cat-315+/PV+ axo-axonic cells were not affected by ketamine. Taken together, PNNs may not play a simple neuroprotective role against ketamine. Because different subclasses of PV+ neurons are considered to play distinct roles in the hippocampal neuronal network, the ketamine-induced subclass imbalance of PV+ neurons may result in abnormal network activity, which underlies the pathophysiology of schizophrenia.

Impulse measurement of laser induced ablation in a vacuum.

An impulse measurement system based on a simple pendulum is newly developed. The system has a resolution of 10-7 Ns for ablation events induced by a single laser at a pulse rate of 2 Hz or less. For ablation events at 10 Hz and above, the system can record the impulse as an average force. The impulse generated by a Nd:YAG pulse laser irradiating a 7075 aluminum alloy is investigated in vacuum. The impulse arises at 3 J/cm2 and the momentum coupling factor, Cm, plateaus at approximately 20 µNs/J over a range of 5 to 50 J/cm2 without producing a plasma shielding effect. Cm is characterized by only fluence independent of pulse width in the range of 10 to 20 ns. This result indicates that it should be feasible to deorbit a 150 kg abandoned satellite at an altitude of 1200 km using a chaser satellite equipped with a 100 W laser.

Lighting system bioinspired by Haworthia obtusa.

Electricity plays an important role in modern societies, with lighting and illumination accounting for approximately one-fifth of the global demand for electricity. Haworthia obtusa has the remarkable ability to collect solar light through a so-called 'window' which allows it to photosynthesise in the dark. Inspired by this unique characteristic, we developed a novel lighting system that does not use electricity. The 'window' of H. obtusa is replicated using a scattering medium that collects solar light and guides it to an optical fibre. The optical fibre then carries the light indoors, where illumination is needed. The efficacy of this unique lighting system was confirmed both numerically and experimentally. The developed system should help in lowering energy consumption.