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BackgroundThe integrity of data in a clinical trial is essential, but the current data management process is too complex and highly labor-intensive. As a result, clinical trials are prone to consuming a lot of budget and time, and there is a risk for human-induced error and data falsification. Blockchain technology has the potential to address some of these challenges. ObjectiveThe aim of the study was to validate a system that enables the security of medical data in a clinical trial using blockchain technology. MethodsWe have developed a blockchain-based data management system for clinical trials and tested the system through a clinical trial for breast cancer. The project was conducted to demonstrate clinical data management using blockchain technology under the regulatory sandbox enabled by the Japanese Cabinet Office. ResultsWe verified and validated the data in the clinical trial using the validation protocol and tested its resilience to data tampering. The robustness of the system was also proven by survival with zero downtime for clinical data registration during a Amazon Web Services disruption event in the Tokyo region on August 23, 2019. ConclusionsWe show that our system can improve clinical trial data management, enhance trust in the clinical research process, and ease regulator burden. The system will contribute to the sustainability of health care services through the optimization of cost for clinical trials.

BackgroundDigital health technologies, including telemedicine, mobile health (mHealth), and remote monitoring, are playing a greater role in medical practice. Safe and accurate management of medical information leads to the advancement of digital health, which in turn results in a number of beneficial effects. Furthermore, mHealth can help lower costs by facilitating the delivery of care and connecting people to their health care providers. Mobile apps help empower patients and health care providers to proactively address medical conditions through near real-time monitoring and treatment, regardless of the location of the patient or the health care provider. Additionally, mHealth data are stored in servers, and consequently, data management that prevents all forms of manipulation is crucial for both medical practice and clinical trials. ObjectiveThe aim of this study was to develop and evaluate a tamper-resistant mHealth system using blockchain technology, which enables trusted and auditable computing using a decentralized network. MethodsWe developed an mHealth system for cognitive behavioral therapy for insomnia using a smartphone app. The volunteer data collected with the app were stored in JavaScript Object Notation format and sent to the blockchain network. Thereafter, we evaluated the tamper resistance of the data against the inconsistencies caused by artificial faults. ResultsElectronic medical records collected using smartphones were successfully sent to a private Hyperledger Fabric blockchain network. We verified the data update process under conditions where all the validating peers were running normally. The mHealth data were successfully updated under network faults. We further ensured that any electronic health record registered to the blockchain network was resistant to tampering and revision. The mHealth data update was compatible with tamper resistance in the blockchain network. ConclusionsBlockchain serves as a tamperproof system for mHealth. Combining mHealth with blockchain technology may provide a novel solution that enables both accessibility and data transparency without a third party such as a contract research organization.

This article discusses the use of machine learning in the early identification of postpartum depression (PPD). The study used demographic information and subjective ratings from pregnant women to construct a prediction model for depression in the first postpartum month. The researchers utilized various machine learning methods and found that the balanced gradient-boosting decision tree (GBDT) model had the highest accuracy, specificity, and positive predictive value. The study identified factors such as depression during pregnancy, maternity blues, age, parity, and temperament as important predictors of PPD. The authors suggest that future research should focus on developing a prediction tool with a higher positive predictive value by incorporating data on the history of depression. [Extracted from the article]

Histone deacetylases (HDACs) play crucial roles in the epigenetic regulation of gene expression. Here, we report CM-Bhc-SAHA, a novel caged HDAC inhibitor, genetically targeting cells of interest. Mammalian cells expressing porcine liver esterase led to the optochemical inhibition of endogenous HDAC activity when treated with CM-Bhc-SAHA and irradiated with 405 nm light. [ABSTRACT FROM AUTHOR]

Real-time imaging of single-molecule fluorescence with a zero-mode waveguide (ZMW) was achieved. With modification of the ZMW geometry, the signal-to-background ratio is twice that obtainable with a conventional ZMW. The improved signal-to-background ratio makes it possible to visualize individual binding--release events between chaperonin GroEL and cochaperonin GroES at a concentration of 5 [micro]M. Two rate constants representing two-timer kinetics in the release of GroES from GroEL were measured with the ZMW, and the measurements agreed well with those made with a total internal reflection fluorescence microscopy. These results indicate that the novel ZMW makes feasible the direct observation of protein--protein interaction at an intracellular concentration in real time.

Abstract Background Kleine-Levin syndrome is a rare sleep disorder of unknown etiology. It is characterized by intermittent periods of excessive sleepiness, cognitive disturbances and behavioral abnormalities. Nine cases of familial Kleine-Levin syndrome have been identified, but there are no reported cases describing twins that are affected by the syndrome. Case presentation We report the cases of 16-year-old monozygotic twin boys who both suffered from Kleine-Levin syndrome. In both cases, the onset of the first episode was preceded by an influenza infection. During symptomatic periods they slept for the entire day except for meals and bathroom visits. Actimetry recordings revealed that during symptomatic periods, daily activity was lower than that of asymptomatic periods, on the other hand, activity during the night was significantly higher in symptomatic periods than asymptomatic periods. Polysomnography (PSG) data during symptomatic periods revealed a decrease in sleep efficiency. Human leukocyte antigen (HLA) typing revealed no DQB1*02 loci. They were administered lithium carbonate but the beneficial effect was limited. Conclusions Our observations suggest that Kleine-Levin syndrome may be due to genetic and autoimmune processes, although etiologic relationship to specific HLA type remains controversial.

State‐dependent modulation of sensory systems has been studied in many organisms and is possibly mediated through neuromodulators such as monoamine neurotransmitters. Among these, dopamine is involved in many aspects of animal behaviour, including movement control, attention, motivation and cognition. However, the precise neural mechanism underlying dopaminergic modulation of behaviour induced by sensory stimuli remains poorly understood. Here, we used Drosophila melanogaster to show that dopamine can modulate the optomotor response to moving visual stimuli including noise. The optomotor response is the head‐turning response to moving objects, which is observed in most sight‐reliant animals including mammals and insects. First, the effects of the dopamine system on the optomotor response were investigated in mutant flies deficient in dopamine receptors D1R1 or D1R2, which are involved in the modulation of sleep‐arousal in flies. We examined the optomotor response in D1R1 knockout (D1R1 KO) and D1R2 knockout (D1R2 KO) flies and found that it was not affected in D1R1 KO flies; however, it was significantly reduced in D1R2 KO flies compared with the wild type. Using cell‐type‐specific expression of an RNA interference construct of D1R2, we identified the fan‐shaped body, a part of the central complex, responsible for dopamine‐mediated modulation of the optomotor response. In particular, pontine cells in the fan‐shaped body seemed important in the modulation of the optomotor response, and their neural activity was required for the optomotor response. These results suggest a novel role of the central complex in the modulation of a behaviour based on the processing of sensory stimulations. [ABSTRACT FROM AUTHOR]

The NLRP3 inflammasome is a molecular complex that translates signals from pathogens and tissue damage into inflammatory responses, and plays crucial roles in numerous neurological diseases. Activation of the NLRP3 inflammasome leads to caspase‐1 dependent cleavage of pro‐IL‐1β to form mature IL‐1β. By acting on the P2X7 purinergic receptor, extracellular ATP is one of the major stimuli that activates the NLRP3 inflammasome. Although microglia express multiple purinergic receptors, their roles in inflammasome‐mediated inflammation are largely unknown. We studied the role of the P2Y12 receptor, a metabotropic P2Y receptor enriched in microglia, on inflammation in vitro. Inhibition of the microglial P2Y12 receptor by PSB0739 or siRNA knockdown suppressed IL‐1β release. P2Y12 receptor‐deficient microglia displayed markedly attenuated IL‐1β mRNA expression and release. P2Y12 receptor blockade also suppressed IL‐6 production. Both IL‐1β and IL‐6 responses were augmented by extracellular ADP or ADP‐βS and were abrogated by PSB0739. Mechanistically, ADP‐βS potentiated NF‐κB activation. In addition, ADP altered mitochondrial membrane potential in combination with ATP and increased the number of caspase‐1 positive cells through the P2Y12 receptor. These results elucidate a novel inflammatory mechanism by which extracellular ADP acts on the P2Y12 receptor to activate NF‐κB and the NLRP3 inflammasome to enhance microglial inflammation. [ABSTRACT FROM AUTHOR]

Background: Blockchain is emerging as an innovative technology for secure data management in many areas, including medical practice. A distributed blockchain network is tolerant against network fault, and the registered data are resistant to tampering and revision. The technology has a high affinity with digital medicine like mobile health (mHealth) and provides reliability to the medical data without labor-intensive third-party contributions. On the other hand, the reliability of the medical data is not insured before registration to the blockchain network. Furthermore, there are issues with regard to how the clients' mobile devices should be dealt with and authenticated in the blockchain network in order to avoid impersonation.Objective: The aim of the study was to design and validate an mHealth system that enables the compatibility of the security and scalability of the medical data using blockchain technology.Methods: We designed an mHealth system that sends medical data to the blockchain network via relay servers. The architecture provides scalability and convenience of operation of the system. In order to ensure the reliability of the data from clients' mobile devices, hash values with chain structure (client hashchain) were calculated in the clients' devices and the results were registered on the blockchain network.Results: The system was applied and deployed in mHealth for insomnia treatment. Clinical trials for mHealth were conducted with insomnia patients. Medical data of the recruited patients were successfully registered with the blockchain network via relay servers along with the hashchain calculated on the clients' mobile devices. The correctness of the data was validated by identifying illegal data, which were made by simulating fraudulent access.Conclusions: Our proposed mHealth system, blockchain combined with client hashchain, ensures compatibility of security and scalability in the data management of mHealth medical practice.Trial Registration: UMIN Clinical Trials Registry UMIN000032951; https://upload.umin.ac.jp/cgi-open- bin/ctr_e/ctr_view.cgi?recptno=R000037564 (Archived by WebCite at http://www.webcitation.org/78HP5iFIw). [ABSTRACT FROM AUTHOR]

Considerable evidence indicates that sleep is essential for learning and memory. Drosophila melanogaster has emerged as a novel model for studying sleep. We previously found a short sleeper mutant, fumin (fmn), and identified its mutation in the dopamine transporter gene. We reported similarities in the molecular basis of sleep and arousal regulation between mammals and Drosophila. In aversive olfactory learning tasks, fmn mutants demonstrate defective memory retention, which suggests an association between sleep and memory. In an attempt to discover additional sleep related genes in Drosophila, we carried out a microarray analysis comparing mRNA expression in heads of fmn and control flies and found that 563 genes are differentially expressed. Next, using the pan-neuronal Gal4 driver elav-Gal4 and UAS-RNA interference (RNAi) to knockdown individual genes, we performed a functional screen. We found that knockdown of the NMDA type glutamate receptor channel gene (Nmdar1) (also known as dNR1) reduced sleep. The NMDA receptor (NMDAR) plays an important role in learning and memory both in Drosophila and mammals. The application of the NMDAR antagonist, MK-801, reduced sleep in control flies, but not in fmn. These results suggest that NMDAR promotes sleep regulation in Drosophila. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) can be used as biomarkers for cancer and other human diseases; therefore, high-throughput and reliable miRNA-quantification methods are required to exploit these markers for diagnostic testing. In this report, we describe the construction of a platform for miRNA-quantification using ligase-assisted sandwich hybridization (LASH) without miRNA-labeling. T4 DNA ligase was used to compensate for the low affinity between miRNAs and two short complementary DNA probes, and it improved the hybridization yield ∼50,000 times. The LASH assay enabled synthesized miR-143 to be quantified at concentrations ranging from 30 fM to 30 pM. The LASH assay could also quantify endogenous miR-143 released from cultured cells as well as some miRNAs in total RNAs derived from blood. Furthermore, multi-color detection enabled us to distinguish between the highly homologous miR-141 and miR-200a. This simple label-free quantification technique is an easy-to-use approach that can be applied to disease diagnosis. [ABSTRACT FROM AUTHOR]

We analyzed the effects of dopamine signaling on the temporal organization of rest and activity in Drosophila melanogaster. Locomotor behaviors were recorded using a video-monitoring system, and the amounts of movements were quantified by using an image processing program. We, first, confirmed that rest bout durations followed long-tailed (i.e., power-law) distributions, whereas activity bout durations did not with a strict method described by Clauset et al. We also studied the effects of circadian rhythm and ambient temperature on rest bouts and activity bouts. The fraction of activity significantly increased during subjective day and at high temperature, but the power-law exponent of the rest bout distribution was not affected. The reduction in rest was realized by reduction in long rest bouts. The distribution of activity bouts did not change drastically under the above mentioned conditions. We then assessed the effects of dopamine. The distribution of rest bouts became less long-tailed and the time spent in activity significantly increased after the augmentation of dopamine signaling. Administration of a dopamine biosynthesis inhibitor yielded the opposite effects. However, the distribution of activity bouts did not contribute to the changes. These results suggest that the modulation of locomotor behavior by dopamine is predominantly controlled by changing the duration of rest bouts, rather than the duration of activity bouts. [ABSTRACT FROM AUTHOR]

Homeothermal animals, such as mammals, maintain their body temperature by heat generation and heat dissipation, while poikilothermal animals, such as insects, accomplish it by relocating to an environment of their favored temperature. Catecholamines are known to regulate thermogenesis and metabolic rate in mammals, but their roles in other animals are poorly understood. The fruit fly, Drosophila melanogaster, has been used as a model system for the genetic studies of temperature preference behavior. Here, we demonstrate that metabolic rate and temperature sensitivity of some temperature sensitive behaviors are regulated by dopamine in Drosophila. Temperature-sensitive molecules like dTrpA1 and shits induce temperature-dependent behavioral changes, and the temperature at which the changes are induced were lowered in the dopamine transporter-defective mutant, fumin. The mutant also displays a preference for lower temperatures. This thermophobic phenotype was rescued by the genetic recovery of the dopamine transporter in dopamine neurons. Flies fed with a dopamine biosynthesis inhibitor (3-iodo-L-tyrosine), which diminishes dopamine signaling, exhibited preference for a higher temperature. Furthermore, we found that the metabolic rate is up-regulated in the fumin mutant. Taken together, dopamine has functions in the temperature sensitivity of behavioral changes and metabolic rate regulation in Drosophila, as well as its previously reported functions in arousal/sleep regulation. [ABSTRACT FROM AUTHOR]

The article presents a study on the role of calcineurin, a heterodimeric phosphatase, in the regulation of sleep in Drosophila melanogaster. It reveals that RNA interference mediated knockdown of calcineurin subunit gene expression in the brain impairs sleep and retention of aversive olfactory memory while its misexpression results in increased sleep. As stated, sleep is essential in learning and memory as it helps in maintaining neural plasticity.

Group II chaperonins found in archaea and in eukaryotic cytosol mediate protein folding without a GroES-like cofactor. The function of the cofactor is substituted by the helical protrusion at the tip of the apical domain, which forms a built-in lid on the central cavity. Although many studies on the change in lid conformation coupled to the binding and hydrolysis of nucleotides have been conducted, the molecular mechanism of lid closure remains poorly understood. Here, we performed a single-molecule polarization modulation to probe the rotation of the helical protrusion of a chaperonin from a hyperthermophilic archaeum, Thermococcus sp. strain KS-1. We detected approximately 35° rotation of the helical protrusion immediately after photorelease of ATP. The result suggests that the conformational change from the open lid to the closed lid state is responsible for the approximately 35° rotation of the helical protrusion. [ABSTRACT FROM AUTHOR]

Abstract: Prefoldin is a chaperone that captures a protein-folding intermediate and transfers it to the group II chaperonin for correct folding. However, kinetics of interactions between prefoldin and substrate proteins have not been investigated. In this study, dissociation constants and dissociation rate constants of unfolded proteins with prefoldin were firstly measured using fluorescence microscopy. Our results suggest that binding and release of prefoldin from hyperthermophilic archaea with substrate proteins were in a dynamic equilibrium. Interestingly, the release of substrate proteins from prefoldin was facilitated when chaperonin was present, supporting a handoff mechanism of substrate proteins from prefoldin to the chaperonin. [Copyright &y& Elsevier]

We have analyzed the dynamics of the chaperonin (GroEL)—cochaperonin (GroES) interaction at the singlemolecule level. In the presence of ATP and non-native protein, binding of GroES to the immobilized GroEL occurred at a rate that is consistent with bulk kinetics measurements. However, the release of GroES from GroEL occurred after a lag period (∼3 s) that was not recognized in earlier bulk-phase studies. This observation suggests a new kinetic intermediate in the GroEL-GroES reaction pathway. [ABSTRACT FROM AUTHOR]

Zero-mode waveguides for single-molecule fluorescence imaging were fabricated using a simple desktop UV nanoimprint lithography system. An array of 30- to 150-nm-diameter nanoholes was successfully fabricated in an aluminum layer on a thin quartz plate by the single-step lift-off process using the UV-curable resist NIAC 707. Using the nanoholes, we performed real-time single-molecule fluorescence imaging to visualize the cochaperonin GroES binding with and dissociating from the chaperonin GroEL immobilized within the nanoholes. The demonstration revealed that the fluorescence from the GroES binding with the GroEL was three times stronger than the fluorescence from the GroES undergoing Brownian motion, and the real-time single-molecule fluorescence imaging was feasible using the zero-mode waveguide fabricated by the UV nanoimprint lithography lift-off process. [ABSTRACT FROM AUTHOR]

The chaperonin, GroEL, is an essential molecular chaperone that mediates protein folding together with its cofactor, GroES, in Escherichia coli. It is widely believed that the two rings of GroEL alternate between the folding active state coupled to GroES binding during the reaction cycle. In other words, an asymmetric GroEL-GroES complex (the bullet-shaped complex) is formed throughout the cycle, whereas a symmetric GroEL-(GroES)2 complex (the football-shaped complex) is not formed. We have recently shown that the football-shaped complex coexists with the bullet-shaped complex during the reaction cycle. However, how protein folding proceeds in the football- shaped complex remains poorly understood. Here, we used GFP as a substrate to visualize protein folding in the footballshaped complex by single-molecule fluorescence techniques. We directly showed that GFP folding occurs in both rings of the football-shaped complex. Remarkably, the folding was a sequential two-step reaction, and the kinetics were in excellent agreement with those in the bullet-shaped complex. These results demonstrate that the same reactions take place independently in both rings of the football-shaped complex to facilitate protein folding. [ABSTRACT FROM AUTHOR]

Abstract: Sleep is a unique behavioral state that is conserved between species, and sleep regulation is closely associated to metabolism and aging. The fruit fly, Drosophila melanogaster has been used to study the molecular mechanism underlying these physiological processes. Here we show that the c-Jun N-terminal Kinase (JNK) gene, known as basket (bsk) in Drosophila, functions in neurons to regulate both sleep and longevity in Drosophila. Pan-neuronal knockdown of JNK mRNA expression by RNA interference resulted in a decrease in both sleep and longevity. A heterozygous knockout of JNK showed similar effects, indicating the molecular specificity. The JNK knockdown showed a normal arousal threshold and sleep rebound, suggesting that the basic sleep mechanism was not affected. JNK is known to be involved in the insulin pathway, which regulates metabolism and longevity. A JNK knockdown in insulin-producing neurons in the pars intercerebralis had slight effects on sleep. However, knocking down JNK in the mushroom body had a significant effect on sleep. These data suggest a unique sleep regulating pathway for JNK. [Copyright &y& Elsevier]

We investigated the signal-to-noise ratio (S/N) of real-time single-molecule fluorescence imaging (SMFI) using zero-mode waveguides (ZMWs). The excitation light and the fluorescence propagating from a molecule in the ZMW were analyzed by computational optics simulation. The dependence of the S/N on the ZMW structure was investigated with the diameter and etching depth as the simulation parameters. We found that the SMFI using a conventional ZMW was near the critical level for detecting binding and dissociation events. We show that etching the glass surface of the ZMW by 60 nm enhances the S/N six times the conventional nonetched ZMWs. The enhanced S/N improves the temporal resolution of the SMFI at physiological concentrations. [ABSTRACT FROM AUTHOR]

Abstract: The fruit fly, Drosophila melanogaster is an established model used for aging and longevity studies and more recently for sleep studies. Mammals and Drosophila share various physiological, pathological, pharmacological and genetic similarities in these processes. In particular, sleep is essential for survival in both species and both have age-associated sleep quality alterations. Here we report that a high calorie diet, which accelerates the aging process and reduces lifespan across species, also accelerates age-associated sleep changes in Drosophila. These changes are more evident in the dopamine transporter mutant, fumin, that displays a short sleep phenotype due to enhanced dopaminergic signaling. With normal food, fumin mutants sleep for only one third of the time that the control flies do, but still show equivalent longevity. However, when on a mildly high calorie diet, their sleep length shows a marked decrease and they have a reduced longevity. These data indicate that the age-associated change in sleep in Drosophila is a physiologically regulated aging process that is tightly linked to calorie intake and that the dopamine level plays an important role. In addition, this provides another evidence that sleep is essential for the longevity of Drosophila. [Copyright &y& Elsevier]