The role of Down syndrome cell adhesion molecule in Down syndrome

Down syndrome (DS) is caused by the presence of an extra copy of the entire or a portion of human chromosome 21 (HSA21). This genomic alteration leads to elevated expression of numerous HSA21 genes, resulting in a variety of health issues in individuals with DS. Among the genes located in the DS "critical region" of HSA21, Down syndrome cell adhesion molecule (DSCAM) plays an important role in neuronal development. There is a growing body of evidence underscoring DSCAM's involvement in various DS-related disorders. This review aims to provide a concise overview of the established functions of DSCAM, with a particular focus on its implications in DS. We delve into the roles that DSCAM plays in DS-associated diseases. In the concluding section of this review, we explore prospective avenues for future research to further unravel DSCAM's role in DS and opportunities for therapeutic treatments.

Medicinal chemistry strategies towards the development of non-covalent SARS-CoV-2 Mpro inhibitors

The main protease (Mpro) of SARS-CoV-2 is an attractive target in anti-COVID-19 therapy for its high conservation and major role in the virus life cycle. The covalent Mpro inhibitor nirmatrelvir (in combination with ritonavir, a pharmacokinetic enhancer) and the non-covalent inhibitor ensitrelvir have shown efficacy in clinical trials and have been approved for therapeutic use. Effective antiviral drugs are needed to fight the pandemic, while non-covalent Mpro inhibitors could be promising alternatives due to their high selectivity and favorable druggability. Numerous non-covalent Mpro inhibitors with desirable properties have been developed based on available crystal structures of Mpro. In this article, we describe medicinal chemistry strategies applied for the discovery and optimization of non-covalent Mpro inhibitors, followed by a general overview and critical analysis of the available information. Prospective viewpoints and insights into current strategies for the development of non-covalent Mpro inhibitors are also discussed.

Undersampling and cumulative class re-decision methods to improve detection of agitation in people with dementia

Agitation is one of the most prevalent symptoms in people with dementia (PwD) that can place themselves and the caregiver's safety at risk. Developing objective agitation detection approaches is important to support health and safety of PwD living in a residential setting. In a previous study, we collected multimodal wearable sensor data from 17 participants for 600 days and developed machine learning models for detecting agitation in 1-min windows. However, there are significant limitations in the dataset, such as imbalance problem and potential imprecise labels as the occurrence of agitation is much rarer in comparison to the normal behaviours. In this paper, we first implemented different undersampling methods to eliminate the imbalance problem, and came to the conclusion that only 20% of normal behaviour data were adequate to train a competitive agitation detection model. Then, we designed a weighted undersampling method to evaluate the manual labeling mechanism given the ambiguous time interval assumption. After that, the postprocessing method of cumulative class re-decision (CCR) was proposed based on the historical sequential information and continuity characteristic of agitation, improving the decision-making performance for the potential application of agitation detection system. The results showed that a combination of undersampling and CCR improved F1-score and other metrics to varying degrees with less training time and data.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13534-023-00313-8.

Neuro-bone tissue engineering: emerging mechanisms, potential strategies, and current challenges

The skeleton is a highly innervated organ in which nerve fibers interact with various skeletal cells. Peripheral nerve endings release neurogenic factors and sense skeletal signals, which mediate bone metabolism and skeletal pain. In recent years, bone tissue engineering has increasingly focused on the effects of the nervous system on bone regeneration. Simultaneous regeneration of bone and nerves through the use of materials or by the enhancement of endogenous neurogenic repair signals has been proven to promote functional bone regeneration. Additionally, emerging information on the mechanisms of skeletal interoception and the central nervous system regulation of bone homeostasis provide an opportunity for advancing biomaterials. However, comprehensive reviews of this topic are lacking. Therefore, this review provides an overview of the relationship between nerves and bone regeneration, focusing on tissue engineering applications. We discuss novel regulatory mechanisms and explore innovative approaches based on nerve-bone interactions for bone regeneration. Finally, the challenges and future prospects of this field are briefly discussed.

Design, Synthesis, and Biological Evaluation of Trisubstituted Piperazine Derivatives as Noncovalent Severe Acute Respiratory Syndrome Coronavirus 2 Main Protease Inhibitors with Improved Antiviral Activity and Favorable Druggability

The ongoing transmission of SARS-CoV-2 necessitates the development of additional potent antiviral agents capable of combating the current highly infectious variants and future coronaviruses. Here, we present the discovery of potent nonpeptide main protease (Mpro) inhibitors with prominent antiviral activity and improved pharmacokinetic properties. Three series of 1,2,4-trisubstituted piperazine derivatives were designed and synthesized, and the optimal GC-78-HCl demonstrated high enzyme-inhibitory potency (IC50 = 0.19 μM) and exhibited excellent antiviral activity (EC50 = 0.40 μM), reaching the same level as Nirmatrelvir (EC50 = 0.38 μM). Additionally, GC-78-HCl displayed potent antiviral activities against various SARS-CoV-2 variants as well as HCoV-OC43 and HCoV-229E, indicating its potential broad-spectrum anticoronaviral activity. Notably, the pharmacokinetic properties of GC-78-HCl were somewhat enhanced compared to those of the lead compound. Furthermore, the cocrystal and molecular docking elucidated the mechanism of action. In conclusion, we discovered a novel nonpeptidic Mpro inhibitor with promising antiviral activity and a favorable pharmacokinetic profile.

Corrigendum to "Photocatalytic oxygen evolution and antibacterial biomimetic repair membrane for diabetes wound repair via HIF1-α pathway" [Mater. Today Bio 20 (2023) 100616]

[This corrects the article DOI: 10.1016/j.mtbio.2023.100616.].

SNR-enhanced signal delivery scheme with delta-sigma modulation in a four-mode fiber system

This Letter proposes a scheme for optimizing the signal-to-noise ratio (SNR) of signal to improve the system performance by a 1 bit delta-sigma modulation (DSM) in a four-mode MDM system for mobile fronthaul. A 1 bit digitalized signal with an SNR of 60 dB from transmitter digital signal processing (Tx DSP) can be achieved. Based on this system, an experimental demonstration of the ultrahigh-order 1048576-QAM signal transmission over a 50 km strong-coupling few-mode fiber (FMF) is successfully realized. With DSP, the bit error rate (BER) of the received 1048576-QAM signals over four modes transmission is below the 20% soft-decision forward error correction (20% SD-FEC) threshold of 2.4 × 10-2. To the best of our knowledge, this is the first time that the combination of DSM technology and strong-coupling MDM system is achieved and that the highest-modulation order with DSM reported in MDM system is reached. This experimental demonstration of the proposed novel scheme in MDM system can provide an effective solution for ultra-large-capacity mobile fronthaul in the future.

Researched Apps Used in Dementia Care for People Living With Dementia and Their Informal Caregivers: Systematic Review on App Features, Security, and Usability

BACKGROUND

Studies have shown that mobile apps have the potential to serve as nonpharmacological interventions for dementia care, improving the quality of life of people living with dementia and their informal caregivers. However, little is known about the needs for and privacy aspects of these mobile apps in dementia care.

OBJECTIVE

This review seeks to understand the landscape of existing mobile apps in dementia care for people living with dementia and their caregivers with respect to app features, usability testing, privacy, and security.

METHODS

ACM Digital Library, Cochrane Central Register of Controlled Trials, Compendex, Embase, Inspec, Ovid MEDLINE, PsycINFO, and Scopus were searched. Studies were included if they included people with dementia living in the community, their informal caregivers, or both; focused on apps in dementia care using smartphones or tablet computers; and covered usability evaluation of the app. Records were independently screened, and 2 reviewers extracted the data. The Centre for Evidence-Based Medicine critical appraisal tool and Mixed Methods Appraisal Tool were used to assess the risk of bias in the included studies. Thematic synthesis was used, and the findings were summarized and tabulated based on each research aim.

RESULTS

Overall, 44 studies were included in this review, with 39 (89%) published after 2015. In total, 50 apps were included in the study, with more apps developed for people living with dementia as end users compared with caregivers. Most studies (27/44, 61%) used tablet computers. The most common app feature was cognitive stimulation. This review presented 9 app usability themes: user interface, physical considerations, screen size, interaction challenges, meeting user needs, lack of self-awareness of app needs, stigma, technological inexperience, and technical support. In total, 5 methods (questionnaires, interviews, observations, logging, and focus groups) were used to evaluate usability. There was little focus on the privacy and security aspects, including data transfer and protection, of mobile apps for people living with dementia.

CONCLUSIONS

The limitations of this review include 1 reviewer conducting the full-text screening, its restriction to studies published in English, and the exclusion of apps that lacked empirical usability testing. As a result, there may be an incomplete representation of the available apps in the field of dementia care. However, this review highlights significant concerns related to the usability, privacy, and security of existing mobile apps for people living with dementia and their caregivers. The findings of this review provide a valuable framework to guide app developers and researchers in the areas of privacy policy development, app development strategies, and the importance of conducting thorough usability testing for their apps. By considering these factors, future work in this field can be advanced to enhance the quality and effectiveness of dementia care apps.

TRIAL REGISTRATION

PROSPERO CRD42020216141; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=216141.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

RR2-10.1159/000514838.

Single-Cell and Spatial Transcriptomics Revealing the Role of IDO1 in HPV+ Cervical Cancer Tumor Immune Microenvironment and Its Implications in Radiotherapy and Immunotherapy

PURPOSE/OBJECTIVE(S)

Persistent infection of human papillomavirus (HPV) is one major etiology of cervical cancer (CC). By now, anti-PD-1 immunotherapy is approved for advanced CC patients, but the response rate was just about 10-20%, tumor immune microenvironment (TIME) might be one factor that affect the efficacy. The indoleamine 2,3-dioxygenase (IDO), a metabolic immune checkpoint, is recently shown to have a correlation-ship with HPV carcinogenesis in CC, with unknown mechanism. This study, using the single cell transcriptomic single-cell sequencing and spatial transcription sequencing analysis/immunologic technology, aimed to exam the role of IDO1 expression in HPV+ CC TIME and explore the changes after radiotherapy.

MATERIALS/METHODS

Newly diagnosed advanced HPV- CC and HPV+ CC patients were tested for the tumor and tumor immune microenvironment (TIME) heterogeneity and their changes after fractionated radiation therapy. Tumor tissues were collected, single cell suspension was made for Single-cell RNA sequencing (SCRNAseq) using the 10 × Genomics, while frozen tissue was embedded for spatial transcriptome sequencing (STRNAseq). Seurat 4.0 was used to cluster and annotate cell clusters and map SCRNAseq data to the STRNAseq data. The specific characters of cell clusters were computed by Gene Set Enrichment Analysis (GSEA). SPOTLight and CellChat were used to analyze cell location and interaction respectively.

RESULTS

A total of 28631 cells were clustered into 31 cell subsets in HPV- CC and HPV+ CC tissues, including baseline (Pre HPV- CC and Pre HPV+ CC) and 3-week after radiotherapy (Post 3w HPV- CC and Post 3w HPV+CC). There were 10431 epithelial cells (Epi) in all these 4 tumor tissues, with heterogenous IDO1 expression, including IDO1-high Epi, IDO1-low Epi, and IDO1-neg Epi. Interestingly, more than 99% of Epi in Pre HPV- CC tissues were IDO1-neg cells, while more than 99% in Pre HPV+ CC tissue were IDO1-high. Furthermore, the proportion of IDO1-high Epi in Pre HPV+ CC patient dropped to 16.7% after radiotherapy, while the proportion of IDO1-low Epi rase to 63.3%. Using GSEA, the characters of IDO1-high Epi group was shown to have positive regulation of leukocyte chemotaxis and negative regulation of cell adhesion and differentiation. IDO1-high Epi cells also had the hallmark of interferon gamma response. These cells could mainly receive regulative information of interferon gamma pathway from exhausted CD8 T cells, which could affect the apoptosis of tumor cells.

CONCLUSION

This study comprehensively analyzed the immune suppressive role of IDO1-high Epi cells in HPV+ CC TIME at the single-cell transcriptional scale and explored their functional characters in CC radiotherapy. This would be able to provide more evidence to combine with radiotherapy and immunotherapy to improve patients' prognosis.

Lesson of urgent bilateral lobar lung transplantation for acute fibrinous and organizing pneumonia: a case report

Background

Acute fibrinous and organizing pneumonia (AFOP) is one of acute expiratory diseases, which occurs rarely with a difficult diagnosis. AFOP is related to an idiopathic cause or autoimmune disease, drug use, infection, cancer, or transplantation. Variation of treatment depends on different institutions. To date, no evidence shows that lobar lung transplantation is applied in an urgent situation such as AFOP.

Case Description

A 33-year-old female patient experienced fever, cough, and dyspnea four days prior to admission. She had no underlying health conditions. Initially, she received oxygen therapy and empiric antimicrobial treatment, but later developed pulmonary consolidation. Pathological examination confirmed the diagnosis of AFOP. Despite receiving standardized treatment involving extracorporeal membrane oxygenation (ECMO) and mechanical ventilation, the patient's respiratory function remained compromised. Consequently, an urgent lobar lung transplantation was performed. However, the patient encountered several challenges including carbapenem-resistant Pseudomonas aeruginosa pneumonia, exophytic granulation tissue, anastomotic stenosis, bronchopleural fistulae, anastomotic infections, septic shock, bacteremia, reperfusion syndrome, primary graft dysfunction, severe renal failure, and critical illness myopathy. Although the patient ultimately recovered and had a favorable survival outcome over 1-year post-discharge through multidisciplinary care, there are several key points to consider. Based on the findings from a systematic review, urgent transplantation may be a potential alternative treatment for AFOP. However, peri-transplantation programs should be enhanced, particularly regarding criteria selection, ECMO management, and the role of enhanced recovery after transplantation.

Conclusions

The case demonstrates the feasibility of bilateral lobar lung transplantation in patients with AFOP, especially in an urgent situation.

The Drosophila homolog of APP promotes Dscam expression to drive axon terminal growth, revealing interaction between Down syndrome genes

Down syndrome (DS) is caused by triplication of human chromosome 21 (HSA21). Although several HSA21 genes have been found to be responsible for aspects of DS, whether and how HSA21 genes interact with each other is poorly understood. DS patients and animal models present with a number of neurological changes, including aberrant connectivity and neuronal morphology. Previous studies have indicated that amyloid precursor protein (APP) and Down syndrome cell adhesion molecule (DSCAM) regulate neuronal morphology and contribute to neuronal aberrations in DS. Here, we report the functional interaction between the Drosophila homologs of these two genes, Amyloid precursor protein-like (Appl) and Dscam (Dscam1). We show that Appl requires Dscam to promote axon terminal growth in sensory neurons. Moreover, Appl increases Dscam protein expression post-transcriptionally. We further demonstrate that regulation of Dscam by Appl does not require the Appl intracellular domain or second extracellular domain. This study presents an example of functional interactions between HSA21 genes, providing insights into the pathogenesis of neuronal aberrations in DS.

BigNeuron: a resource to benchmark and predict performance of algorithms for automated tracing of neurons in light microscopy datasets

BigNeuron is an open community bench-testing platform with the goal of setting open standards for accurate and fast automatic neuron tracing. We gathered a diverse set of image volumes across several species that is representative of the data obtained in many neuroscience laboratories interested in neuron tracing. Here, we report generated gold standard manual annotations for a subset of the available imaging datasets and quantified tracing quality for 35 automatic tracing algorithms. The goal of generating such a hand-curated diverse dataset is to advance the development of tracing algorithms and enable generalizable benchmarking. Together with image quality features, we pooled the data in an interactive web application that enables users and developers to perform principal component analysis, t-distributed stochastic neighbor embedding, correlation and clustering, visualization of imaging and tracing data, and benchmarking of automatic tracing algorithms in user-defined data subsets. The image quality metrics explain most of the variance in the data, followed by neuromorphological features related to neuron size. We observed that diverse algorithms can provide complementary information to obtain accurate results and developed a method to iteratively combine methods and generate consensus reconstructions. The consensus trees obtained provide estimates of the neuron structure ground truth that typically outperform single algorithms in noisy datasets. However, specific algorithms may outperform the consensus tree strategy in specific imaging conditions. Finally, to aid users in predicting the most accurate automatic tracing results without manual annotations for comparison, we used support vector machine regression to predict reconstruction quality given an image volume and a set of automatic tracings.

Photocatalytic oxygen evolution and antibacterial biomimetic repair membrane for diabetes wound repair via HIF1-α pathway

Diabetic wounds always have puzzled patients and caused serious social problems. Due to the lack of local blood vessels, severe hypoxia is generated in the defect area, which is an essential reason for the difficulty of wound healing. We have constructed a photocatalytic oxygen evolution and antibacterial biomimetic repair membrane to solve the problems of wound repair. A scanning electron microscope and transmission electron microscope characterized the biomimetic repair membrane. The oxygen evolution of the biomimetic membrane was tested by an oxygen meter. The excellent antibacterial performance of the biomimetic repair membrane was also verified by co-culture with Staphylococcus aureus and Escherichia coli. It was confirmed that the expression of collagen and HIF1-α in fibroblasts was significantly increased in vitro. And the mitochondrial activity of the vascular and nerve was increased considerably. In vivo, the healing time of diabetes wounds treated with the biomimetic repair membrane was significantly reduced, the collagen and the number of pores were increased considerably, and vascular regeneration was enhanced. The biomimetic repair membrane has an excellent performance in photocatalytic oxygen evolution and antibacterial and can significantly promote the repair of diabetes wounds. This will provide a promising treatment for diabetes wound repair.

Epstein-Barr virus immediate-early protein Zta mediates the proliferation and migration of HER2-overexpressing cancer cells

Epstein-Barr virus immediate-early protein Zta plays an active role in altering cellular gene expression, which may be fundamentally linked to the viral life cycle, cell cycle, cell growth, and differentiation. HER2 is associated with a wide variety of human cancers, and its knockdown significantly reverses the malignant features of HER2-positive cancers. The aim of this study was to investigate the potential role of Zta in regulating HER2 expression and phenotype changes of MDA-MB-453 cells. Our results indicate that ectopic expression of Zta resulted in downregulation of the HER2 protein in cancer cells (MDA-MB-453, SKBR-3, BT474, and SKOV-3). The Zta protein significantly decreased HER2 mRNA and protein expression in MDA-MB-453 cells in a dose-dependent manner. Mechanistically, Zta recognized and targeted the promoter of HER2 gene, reducing the transcriptional activity of the HER2 gene. Zta induced G0/G1 arrest of MDA-MB-453 cells, inhibiting their proliferation and migration activity. These data suggest that Zta may act as a transforming suppressor of the HER2 gene.

Approaches to vascularizing human brain organoids

A major challenge in brain organoid technologies is the lack of vasculature. In recent years, innovative approaches have been taken to meet this challenge. A 2020 paper published in PLOS Biology exemplifies the approaches used in this booming field.

Cross-modal modulation gates nociceptive inputs in Drosophila

Animals' response to a stimulus in one sensory modality is usually influenced by other modalities.1 One important type of multisensory integration is the cross-modal modulation, in which one sensory modality modulates (typically inhibits) another. Identification of the mechanisms underlying cross-modal modulations is crucial for understanding how sensory inputs shape animals' perception and for understanding sensory processing disorders.2,3,4 However, the synaptic and circuit mechanisms that underlie cross-modal modulation are poorly understood. This is due to the difficulty of separating cross-modal modulation from multisensory integrations in neurons that receive excitatory inputs from two or more sensory modalities5-in which case it is unclear what the modulating or modulated modality is. In this study, we report a unique system for studying cross-modal modulation by taking advantage of the genetic resources in Drosophila. We show that gentle mechanical stimuli inhibit nociceptive responses in Drosophila larvae. Low-threshold mechanosensory neurons inhibit a key second-order neuron in the nociceptive pathway through metabotropic GABA receptors on nociceptor synaptic terminals. Strikingly, this cross-modal inhibition is only effective when nociceptor inputs are weak, thus serving as a gating mechanism for filtering out weak nociceptive inputs. Our findings unveil a novel cross-modal gating mechanism for sensory pathways.

DSCAM gene triplication causes excessive GABAergic synapses in the neocortex in Down syndrome mouse models

Down syndrome (DS) is caused by the trisomy of human chromosome 21 (HSA21). A major challenge in DS research is to identify the HSA21 genes that cause specific symptoms. Down syndrome cell adhesion molecule (DSCAM) is encoded by a HSA21 gene. Previous studies have shown that the protein level of the Drosophila homolog of DSCAM determines the size of presynaptic terminals. However, whether the triplication of DSCAM contributes to presynaptic development in DS remains unknown. Here, we show that DSCAM levels regulate GABAergic synapses formed on neocortical pyramidal neurons (PyNs). In the Ts65Dn mouse model for DS, where DSCAM is overexpressed due to DSCAM triplication, GABAergic innervation of PyNs by basket and chandelier interneurons is increased. Genetic normalization of DSCAM expression rescues the excessive GABAergic innervations and the increased inhibition of PyNs. Conversely, loss of DSCAM impairs GABAergic synapse development and function. These findings demonstrate excessive GABAergic innervation and synaptic transmission in the neocortex of DS mouse models and identify DSCAM overexpression as the cause. They also implicate dysregulated DSCAM levels as a potential pathogenic driver in related neurological disorders.

LabGym: Quantification of user-defined animal behaviors using learning-based holistic assessment

Quantifying animal behavior is important for biological research. Identifying behaviors is the prerequisite of quantifying them. Current computational tools for behavioral quantification typically use high-level properties such as body poses to identify the behaviors, which constrains the information available for a holistic assessment. Here we report LabGym, an open-source computational tool for quantifying animal behaviors without this constraint. In LabGym, we introduce "pattern image" to represent the animal's motion pattern, in addition to "animation" that shows all spatiotemporal details of a behavior. These two pieces of information are assessed holistically by customizable deep neural networks for accurate behavior identifications. The quantitative measurements of each behavior are then calculated. LabGym is applicable for experiments involving multiple animals, requires little programming knowledge to use, and provides visualizations of behavioral datasets. We demonstrate its efficacy in capturing subtle behavioral changes in diverse animal species.

Probing many-body dynamics in a two-dimensional dipolar spin ensemble

The most direct approach for characterizing the quantum dynamics of a strongly interacting system is to measure the time evolution of its full many-body state. Despite the conceptual simplicity of this approach, it quickly becomes intractable as the system size grows. An alternate approach is to think of the many-body dynamics as generating noise, which can be measured by the decoherence of a probe qubit. Here we investigate what the decoherence dynamics of such a probe tells us about the many-body system. In particular, we utilize optically addressable probe spins to experimentally characterize both static and dynamical properties of strongly interacting magnetic dipoles. Our experimental platform consists of two types of spin defects in nitrogen delta-doped diamond: nitrogen-vacancy colour centres, which we use as probe spins, and a many-body ensemble of substitutional nitrogen impurities. We demonstrate that the many-body system's dimensionality, dynamics and disorder are naturally encoded in the probe spins' decoherence profile. Furthermore, we obtain direct control over the spectral properties of the many-body system, with potential applications in quantum sensing and simulation.

Privacy-protecting behaviours of risk detection in people with dementia using videos

BACKGROUND

People living with dementia often exhibit behavioural and psychological symptoms of dementia that can put their and others' safety at risk. Existing video surveillance systems in long-term care facilities can be used to monitor such behaviours of risk to alert the staff to prevent potential injuries or death in some cases. However, these behaviours of risk events are heterogeneous and infrequent in comparison to normal events. Moreover, analysing raw videos can also raise privacy concerns.

PURPOSE

In this paper, we present two novel privacy-protecting video-based anomaly detection approaches to detect behaviours of risks in people with dementia.

METHODS

We either extracted body pose information as skeletons or used semantic segmentation masks to replace multiple humans in the scene with their semantic boundaries. Our work differs from most existing approaches for video anomaly detection that focus on appearance-based features, which can put the privacy of a person at risk and is also susceptible to pixel-based noise, including illumination and viewing direction. We used anonymized videos of normal activities to train customized spatio-temporal convolutional autoencoders and identify behaviours of risk as anomalies.

RESULTS

We showed our results on a real-world study conducted in a dementia care unit with patients with dementia, containing approximately 21 h of normal activities data for training and 9 h of data containing normal and behaviours of risk events for testing. We compared our approaches with the original RGB videos and obtained a similar area under the receiver operating characteristic curve performance of 0.807 for the skeleton-based approach and 0.823 for the segmentation mask-based approach.

CONCLUSIONS

This is one of the first studies to incorporate privacy for the detection of behaviours of risks in people with dementia. Our research opens up new avenues to reduce injuries in long-term care homes, improve the quality of life of residents, and design privacy-aware approaches for people living in the community.

Endogenous Electric Field-Coupled PD@BP Biomimetic Periosteum Promotes Bone Regeneration through Sensory Nerve via Fanconi Anemia Signaling Pathway

To treat bone defects, repairing the nerve-rich periosteum is critical for repairing the local electric field. In this study, an endogenous electric field is coupled with 2D black phosphorus electroactive periosteum to explore its role in promoting bone regeneration through nerves. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are used to characterize the electrically active biomimetic periosteum. Here, the in vitro effects exerted by the electrically active periosteum on the transformation of Schwann cells into the repair phenotype, axon initial segment (AIS) and dense core vesicle (DCV) of sensory neurons, and bone marrow mesenchymal stem cells are assessed using SEM, immunofluorescence, RNA-sequencing, and calcium ion probes. The electrically active periosteum stimulates Schwann cells into a neuroprotective phenotype via the Fanconi anemia pathway, enhances the AIS effect of sensory neurons, regulates DCV transport, and releases neurotransmitters, promoting the osteogenic transformation of bone marrow mesenchymal stem cells. Microcomputed tomography and other in vivo techniques are used to study the effects of the electrically active periosteum on bone regeneration. The results show that the electrically active periosteum promotes nerve-induced osteogenic repair, providing a potential clinical strategy for bone regeneration.

Analysis of Mouse Brain Sections by Live-cell Time-lapse Confocal Microscopy

The developing cerebral cortex of mammals is generated from nascent pyramidal neurons, which radially migrate from their birthplace in the ventral part of the neural tube to the cortical surface. Subtle aberrations in this process may cause significant changes in cortical structure and lead to developmental neurological disorders. During pyramidal neuron migration, we recently showed that the migrating neuron, which bypasses its last preceding neuron, is critical for its proper positioning and contributes to cerebral cortex thickness. Studying this process requires an imaging system with single-cell resolution and a prolonged observation window. Therefore, we built a system to maintain an organotypic brain slice on the stage of a Leica SP5 confocal microscope, which facilitated high-resolution imaging over a 12-hour time-lapse observation period of cellular events during neuron migration. Here, we share our protocol along with guidelines for overcoming difficulties during the setup. This protocol facilitates the observation of, but is not limited to, neurodevelopmental and pathological processes occurring during neuron migration.

Photosensitive and Conductive Hydrogel Induced Innerved Bone Regeneration for Infected Bone Defect Repair

Repairing infected bone defects is a challenge in the field of orthopedics because of the limited self-healing capacity of bone tissue and the susceptibility of refractory materials to bacterial activity. Innervation is the initiating factor for bone regeneration and plays a key regulatory role in subsequent vascularization, ossification, and mineralization processes. Infection leads to necrosis of local nerve fibers, impeding the repair of infected bone defects. Herein, a biomaterial that can induce skeletal-associated neural network reconstruction and bone regeneration with high antibacterial activity is proposed for the treatment of infected bone defects. A photosensitive conductive hydrogel is prepared by incorporating magnesium-modified black phosphorus (BP@Mg) into gelatin methacrylate (GelMA). The near-infrared irradiation-based photothermal and photodynamic treatment of black phosphorus endows it with strong antibacterial activity, improving the inflammatory microenvironment and reducing bacteria-induced bone tissue damage. The conductive nanosheets and bioactive ions released from BP@Mg synergistically improve the migration and secretion of Schwann cells, promote neurite outgrowth, and facilitate innerved bone regeneration. In an infected skull defect model, the GelMA-BP@Mg hydrogel shows efficient antibacterial activity and promotes bone and CGRP⁺ nerve fiber regeneration. The phototherapy conductive hydrogel provides a novel strategy based on skeletal-associated innervation for infected bone defect repair.

Discovery and Crystallographic Studies of Nonpeptidic Piperazine Derivatives as Covalent SARS-CoV-2 Main Protease Inhibitors

The spread of SARS-CoV-2 keeps threatening human life and health, and small-molecule antivirals are in demand. The main protease (Mpro) is an effective and highly conserved target for anti-SARS-CoV-2 drug design. Herein, we report the discovery of potent covalent non-peptide-derived Mpro inhibitors. A series of covalent compounds with a piperazine scaffold containing different warheads were designed and synthesized. Among them, GD-9 was identified as the most potent compound with a significant enzymatic inhibition of Mpro (IC50 = 0.18 μM) and good antiviral potency against SARS-CoV-2 (EC50 = 2.64 μM), similar to that of remdesivir (EC50 = 2.27 μM). Additionally, GD-9 presented favorable target selectivity for SARS-CoV-2 Mpro versus human cysteine proteases. The X-ray co-crystal structure confirmed our original design concept showing that GD-9 covalently binds to the active site of Mpro. Our nonpeptidic covalent inhibitors provide a basis for the future development of more efficient COVID-19 therapeutics.

Aptamer engineering exosomes loaded on biomimetic periosteum to promote angiogenesis and bone regeneration by targeting injured nerves via JNK3 MAPK pathway

Repairing critical bone defects is a complex problem in the clinic. The periosteum rich in nerve plays a vital role in initiating and regulating bone regeneration. However, current studies have paid little attention to repairing nerves in the periosteum to promote bone regeneration. Thus, it is essential to construct bionic periosteum with the targeted injured nerves in the periosteum. We coupled phosphatidylserine (PS) targeted aptamers with repair Schwann cell exosomes to construct exosome@aptamer (EA). Then through PEI, EA was successfully built on the surface of the electrospun fiber, which was PCL@PEI@exosome@aptamer (PPEA). Through SEM, TEM, and other technologies, PPEA was characterized. Experiments prove in vivo and in vitro that it has an excellent repair effect on damaged nerves and regeneration of vascular and bones. In vivo, we confirmed that biomimetic periosteum has an apparent ability to promote nerve and bone regeneration by using Microcomputer tomography, hematoxylin-eosin, Masson, and Immunofluorescence. In vitro, we used Immunofluorescence, Real-Time Quantitative PCR, Alkaline phosphatase staining, and other tests to confirm that it has central nerve, blood vessel, and bone regeneration ability. The PPEA biomimetic periosteum has apparent neurogenic, angiogenic, and osteogenic effects. The PPEA biomimetic periosteum will provide a promising method for treating bone defects.

•

To construct a biomimetic periosteum that can target injured axons and bone regeneration.

•

PS targeted aptamer is coupled with repair Schwann cell exosomes.

•

PEI self-assembly was used for the PCL electrospun biomimetic membrane loading.

•

It targeted and repaired the injured axons and promoted the secretion of CGRP and SP.

•

Biomimetic periosteum promotes vascular regeneration and bone regeneration.

Risk factors of post-polypectomy bleeding and recurrence in children with colorectal polyps after endoscopic mucosal resection: a retrospective cohort study

BACKGROUND

The incidence rate of colorectal polyps in children has gradually increased in recent years. It is still unclear whether endoscopic mucosal resection (EMR) can be performed in children with colorectal polyps as well as their incidences of post-polypectomy bleeding and recurrence. This retrospective study was performed to explore the feasible of EMR in children with colorectal polyps and analyze the risk factors of post-polypectomy bleeding and recurrence.

METHODS

Patients aged younger than 18 years diagnosed with colorectal polyps and received EMR for polypectomy between January 2017 and December 2021 were included in this study. The baseline data of included patients were retrospectively collected. All complications related to polypectomy were recorded during follow up via telephone, internet, or outpatient department, including post-polypectomy bleeding, perforation and polyp recurrence. Patients with and without post-polypectomy complications were divided into 2 groups. The risk factors of post-polypectomy bleeding and polyp recurrence were analyzed using multivariable logistic regression models after adjusting potential risk factors using univariable regression models.

RESULTS

A total of 589 patients were included in this retrospective study. There were 333 male patients and 256 female patients, and their average age was 4.4±1.9 years old. The average diameter of their polyps was 8.4±2.8 mm, and 542 (92.0%) polyps presented as pedunculated lesions. A total of 540 (91.7%) polyps were diagnosed as juvenile polyps and 509 (86.4%) patients had only 1 polyp. There were a total of 75 cases of post-polypectomy complications (12.7%). The most common complication was early post-polypectomy bleeding (5.3%), followed by polyp recurrence (3.7%). Post-polypectomy bleeding occurred the most on the third and fourth day after EMR polypectomy. Larger polyps (OR =1.742, P<0.001), sessile lesions (OR =3.150, P=0.019), and multiple polyps (OR =4.372, P=0.003) were identified to be related to the incidence of post-polypectomy bleeding. Besides, sessile lesions (OR =3.887, P=0.026) were identified as the main risk factor and older patients (OR =0.606, P=0.004) had lower potential for post-polypectomy recurrence.

CONCLUSIONS

More attention should be paid to large, sessile, and multiple polyps during the procedure of EMR in children. The small number of patients in this study limits further analysis of results and a large sample study should be performed.

Recent Advances in the Application of Natural and Synthetic Polymer-Based Scaffolds in Musculoskeletal Regeneration

The musculoskeletal system plays a critical role in providing the physical scaffold and movement to the mammalian body. Musculoskeletal disorders severely affect mobility and quality of life and pose a heavy burden to society. This new field of musculoskeletal tissue engineering has great potential as an alternative approach to treating large musculoskeletal defects. Natural and synthetic polymers are widely used in musculoskeletal tissue engineering owing to their good biocompatibility and biodegradability. Even more promising is the use of natural and synthetic polymer composites, as well as the combination of polymers and inorganic materials, to repair musculoskeletal tissue. Therefore, this review summarizes the progress of polymer-based scaffolds for applications of musculoskeletal tissue engineering and briefly discusses the challenges and future perspectives.

Dual Leucine Zipper Kinase Regulates Dscam Expression through a Noncanonical Function of the Cytoplasmic Poly(A)-Binding Protein

Dual leucine zipper kinase (DLK) plays a pivotal role in the development, degeneration, and regeneration of neurons. DLK can regulate gene expression post-transcriptionally, but the underlying mechanism remains poorly understood. The Drosophila DLK, Wallenda (Wnd), regulates the expression of Down syndrome cell adhesion molecule (Dscam) to control presynaptic arbor growth. This regulation is mediated by the 3' untranslated region (3'UTR) of Dscam mRNA, which suggests that RNA binding proteins (RBPs) mediate DLK function. We performed a genome-wide cell-based RNAi screen of RBPs and identified the cytoplasmic poly(A)-binding protein, pAbp, as an RBP that mediates Wnd-induced increase in Dscam expression. Genetic analysis shows that Wnd requires pAbp for promoting presynaptic arbor growth and for enhancing Dscam expression. Our analysis revealed that Dscam mRNAs harbor short poly(A) tails. We identified a region in Dscam 3'UTR that specifically interacts with pAbp. Removing this region significantly reduced Wnd-induced increase in Dscam expression. These suggest that a noncanonical interaction of PABP with the 3'UTR of target transcripts is essential for DLK functions.SIGNIFICANCE STATEMENT The kinase DLK plays key roles in a multitude of neuronal responses, including axon development, neurodegeneration, and nerve injury. Previous studies show that DLK acts via mRNAs to regulate protein synthesis, but how DLK does so is poorly understood. This study demonstrates that DLK regulates the synthesis of Dscam through the poly(A)-binding protein PABP-C. Whereas PABP-C is known as a general translational activator, our study shows that DLK-mediated Dscam expression involves a noncanonical interaction between PABP-C and the Dscam mRNA, which leads to a selective regulation of Dscam translation by PABP-C. Thus, our study provides novel insights into the mechanisms that underlie the function of DLK and regulation of gene expression of PABP-C.

Migrating Pyramidal Neurons Require DSCAM to Bypass the Border of the Developing Cortical Plate

During mammalian neocortex development, nascent pyramidal neurons migrate along radial glial cells and overtake earlier-born neurons to terminate at the front of the developing cortical plate (CP), leading to the outward expansion of the CP border. While much has been learned about the cellular and molecular mechanisms that underlie the migration of pyramidal neurons, how migrating neurons bypass the preceding neurons at the end of migration to reach their final positions remains poorly understood. Here, we report that Down syndrome cell adhesion molecule (DSCAM) is required for migrating neurons to bypass their postmigratory predecessors during the expansion of the upper cortical layers. DSCAM is a type I transmembrane cell adhesion molecule. It has been linked to Down syndrome through its location on Chromosome 21 trisomy and to autism spectrum disorders through loss-of-function mutations. Ex vivo time-lapse imaging demonstrates that DSCAM is required for migrating neurons to bypass their postmigratory predecessors, crossing the CP border to expand the upper cortical layers. In DSCAM-deficient cortices, migrating neurons stop prematurely under the CP border, leading to thinner upper cortical layers with higher neuronal density. We further show that DSCAM weakens cell adhesion mediated by N-cadherin in the upper cortical plate, allowing migrating neurons to traverse the CP border and expand the CP. These findings suggest that DSCAM is required for proper migratory termination and final positioning of nascent pyramidal neurons, which may provide insight into brain disorders that exhibit thinner upper layers of the cerebral cortex without neuronal loss.SIGNIFICANCE STATEMENT Newly born neurons in the developing mammalian neocortex migrate outward toward the cortical surface, bypassing earlier born neurons to expand the developing cortex. How migrating neurons bypass the preceding neurons and terminate at the front of the expanding cortex remains poorly understood. We demonstrate that Down syndrome cell adhesion molecule (DSCAM), linked to Down syndrome and autism spectrum disorder, is required by migrating neurons to bypass their postmigratory predecessors and terminate migration in the outwardly expanding cortical layer. Migrating neurons deficient in DSCAM stop prematurely, failing to expand the cortex. We further show that DSCAM likely mediates migratory termination by weakening cell adhesion mediated by N-cadherin.

Technology-Based Compensation Assessment and Detection of Upper Extremity Activities of Stroke Survivors: Systematic Review

Background

Upper extremity (UE) impairment affects up to 80% of stroke survivors and accounts for most of the rehabilitation after discharge from the hospital release. Compensation, commonly used by stroke survivors during UE rehabilitation, is applied to adapt to the loss of motor function and may impede the rehabilitation process in the long term and lead to new orthopedic problems. Intensive monitoring of compensatory movements is critical for improving the functional outcomes during rehabilitation.

Objective

This review analyzes how technology-based methods have been applied to assess and detect compensation during stroke UE rehabilitation.

Methods

We conducted a wide database search. All studies were independently screened by 2 reviewers (XW and YF), with a third reviewer (BY) involved in resolving discrepancies. The final included studies were rated according to their level of clinical evidence based on their correlation with clinical scales (with the same tasks or the same evaluation criteria). One reviewer (XW) extracted data on publication, demographic information, compensation types, sensors used for compensation assessment, compensation measurements, and statistical or artificial intelligence methods. Accuracy was checked by another reviewer (YF). Four research questions were presented. For each question, the data were synthesized and tabulated, and a descriptive summary of the findings was provided. The data were synthesized and tabulated based on each research question.

Results

A total of 72 studies were included in this review. In all, 2 types of compensation were identified: disuse of the affected upper limb and awkward use of the affected upper limb to adjust for limited strength, mobility, and motor control. Various models and quantitative measurements have been proposed to characterize compensation. Body-worn technology (25/72, 35% studies) was the most used sensor technology to assess compensation, followed by marker-based motion capture system (24/72, 33% studies) and marker-free vision sensor technology (16/72, 22% studies). Most studies (56/72, 78% studies) used statistical methods for compensation assessment, whereas heterogeneous machine learning algorithms (15/72, 21% studies) were also applied for automatic detection of compensatory movements and postures.

Conclusions

This systematic review provides insights for future research on technology-based compensation assessment and detection in stroke UE rehabilitation. Technology-based compensation assessment and detection have the capacity to augment rehabilitation independent of the constant care of therapists. The drawbacks of each sensor in compensation assessment and detection are discussed, and future research could focus on methods to overcome these disadvantages. It is advised that open data together with multilabel classification algorithms or deep learning algorithms could benefit from automatic real time compensation detection. It is also recommended that technology-based compensation predictions be explored.

The molecular mechanisms that underlie neural network assembly

Neural networks are groups of interconnected neurons, which collectively give rise to emergent neural activities and functions that cannot be explained by the activity of single neurons. How neural networks are assembled is poorly understood. While all aspects of neuronal development are essential for the assembly of a functional neural network, we know little about high-level principles that govern neural network assembly beyond the basic steps of neuronal development. In this review, I use vertebrate spinal motor columns, Drosophila larval motor circuit, and the lamination in the vertebrate inner retina to highlight the spatial codes, temporal codes, and cell adhesion codes for neural network assembly. Nevertheless, these examples only show preliminary connections between neural network development and their functions. Much needs to be done to understand the molecular mechanisms that underlie the assembly of functional neural networks.

The Development and Concurrent Validity of a Multi-Sensor-Based Frailty Toolkit for In-Home Frailty Assessment

Early identification of frailty is crucial to prevent or reverse its progression but faces challenges due to frailty’s insidious onset. Monitoring behavioral changes in real life may offer opportunities for the early identification of frailty before clinical visits. This study presented a sensor-based system that used heterogeneous sensors and cloud technologies to monitor behavioral and physical signs of frailty from home settings. We aimed to validate the concurrent validity of the sensor measurements. The sensor system consisted of multiple types of ambient sensors, a smart speaker, and a smart weight scale. The selection of these sensors was based on behavioral and physical signs associated with frailty. Older adults’ perspectives were also included in the system design. The sensor system prototype was tested in a simulated home lab environment with nine young, healthy participants. Cohen’s Kappa and Bland−Altman Plot were used to evaluate the agreements between the sensor and ground truth measurements. Excellent concurrent validity was achieved for all sensors except for the smart weight scale. The bivariate correlation between the smart and traditional weight scales showed a strong, positive correlation between the two measurements (r = 0.942, n = 24, p < 0.001). Overall, this work showed that the Frailty Toolkit (FT) is reliable for monitoring physical and behavioral signs of frailty in home settings.

Bioinspired Multifunctional Black Phosphorus Hydrogel with Antibacterial and Antioxidant Properties: A Stepwise Countermeasure for Diabetic Skin Wound Healing

Cutaneous wound healing, especially diabetic wound healing, is a common clinical challenge. Reactive oxygen species (ROS) and bacterial infection are two major detrimental states that induce oxidative stress and inflammatory responses and impede angiogenesis and wound healing. A derivative of the metabolite itaconate, 4-octyl itaconate (4OI) has attracted increasing research interest in recent years due to its antioxidant and anti-inflammatory properties. In this study, 4OI-modified black phosphorus (BP) nanosheets are incorporated into a photosensitive, multifunctional gelatin methacrylamide hydrogel to produce a new photothermal therapy (PTT) and photodynamic therapy (PDT) system with antibacterial and antioxidant properties for diabetic wound regeneration. Under laser irradiation, the 4OI-BP-entrapped hydrogel enables rapid gelation, forming a membrane on wounds, and offers high PTT and PDT efficacy to eliminate bacterial infection. Without laser irradiation, BP acts as a carrier and controls the release of 4OI, with which it synergistically enhances antioxidant activity, thus alleviating excessive ROS damage to endothelial cells, promoting neovascularization, and facilitating faster diabetic wound closure. These findings indicate that 4OI-BP-entrapped multifunctional hydrogel provides a stepwise countermeasure with antibacterial and antioxidant properties for enhanced diabetic wound healing and may lead to novel therapeutic interventions for diabetic ulcers.

Comparative molecular dynamics study on interaction of acetamide and glycerol with phospholipid bilayer

BACKGROUND

The exact mechanisms that acetamide and glycerol interact with cell membrane remains a matter of debate.

OBJECTIVE

To investigate the microscopic interactions of acetamide and glycerol with phospholipid bilayers at various temperatures.

MATERIALS AND METHODS

Molecular dynamics simulations of a hydrated dipalmitoyl-phosphatidylcholine (DPPC) bilayer in the presence of glycerol and acetamide were performed. The system contains 128 lipids and about 700 cryoprotectant molecules, and simulations extended to 15 ns.

RESULT

When compared to glycerol, acetamide shows a stronger affinity with water rather than the lipid bilayer.

CONCLUSION

The knowledge of the mixing dynamics of present system helps to develop better cryoprotective formulas and to propose more optimal cooling/warming protocols.

Evaluating predictability in outdoor mobility: A potential pathway to personalized assistance for people with dementia

BACKGROUND

People with dementia (PwD) often become lost, which is commonly attributed to spatial disorientation, one of the earliest symptoms of dementia, particularly of the Alzheimer's disease type. Spatial disorientation can limit a person's ability to navigate in an outdoor environment. As a result, PwD experience outdoor mobility decline, which, in turn, can have a negative impact on their cognitive functions. Thus, enabling safe outdoor mobility is important for dementia research. Artificial Intelligence (AI) methods in conjunction with Global Positioning System (GPS) data show great potential for supporting the outdoor mobility needs of PwD. The objective of this work is to evaluate the extent to which we can predict future destinations of PwD by learning from their past mobility habits.

METHOD

Eight cognitively-intact older adults (CTL) and seven older adults with dementia completed four weeks of GPS recording. Each participant's stops and trips were extracted from their trajectories. We determined the predictability of each participant's mobility patterns using three approaches. First, we assumed each stop is visited with equal probability, thus, disregarding temporal aspects of travel. Next, we built on the previous approach by including stop visitation probability, thus, capturing the heterogeneity of visitations. Finally, to capture the full spatiotemporal characteristics of mobility, we added in-depth temporal characteristics including the visitation frequency, the order in which the stops were visited, and the time spent at each stop.

RESULT

Relying solely on the spatial dimension of mobility yielded no predictive power across the two groups. Adding the heterogeneity of visitation patterns, we observed an increase in the predictability power; PwD displayed a trend toward higher predictability compared to the CTLs, but the student's t-test did not reach statistical significance (0.833±0.085vs.0.768±0.029, t(13)=-2.06, p=0.06; d=-1.07). Finally, relying on full spatiotemporal characteristics, a 4-week record of mobility patterns displayed 95% (SD=2%) and 92% (SD=1%) predictability among PwD and CTLs, respectively. This value was significantly higher among PwD, t(13) = -3.39, p<.01; d=-1.75.

CONCLUSION

Our findings offer new perspectives on the predictive mobility models based on GPS data and AI that can be used to provide personalized assistance for outdoor navigation of people with dementia.

Wearable multimodal sensors for the detection of behavioral and psychological symptoms of dementia using personalized machine learning models

Introduction

Behavioral and psychological symptoms of dementia (BPSD) signal distress or unmet needs and present a risk to people with dementia and their caregivers. Variability in the expression of these symptoms is a barrier to the performance of digital biomarkers. The aim of this study was to use wearable multimodal sensors to develop personalized machine learning models capable of detecting individual patterns of BPSD.

Methods

Older adults with dementia and BPSD (n = 17) on a dementia care unit wore a wristband during waking hours for up to 8 weeks. The wristband captured motion (accelerometer) and physiological indicators (blood volume pulse, electrodermal activity, and skin temperature). Agitation or aggression events were tracked, and research staff reviewed videos to precisely annotate the sensor data. Personalized machine learning models were developed using 1‐minute intervals and classifying the presence of behavioral symptoms, and behavioral symptoms by type (motor agitation, verbal aggression, or physical aggression).

Results

Behavioral events were rare, representing 3.4% of the total data. Personalized models classified behavioral symptoms with a median area under the receiver operating curve (AUC) of 0.87 (range 0.64–0.95). The relative importance of the different sensor features to the predictive models varied both by individual and behavior type.

Discussion

Patterns of sensor data associated with BPSD are highly individualized, and future studies of the digital phenotyping of these behaviors would benefit from personalization.

Magnesium-based materials in orthopaedics: material properties and animal models

As a new generation of medical metal materials, degradable magnesium-based materials have excellent mechanical properties and osteogenic promoting ability, making them promising materials for the treatment of refractory bone diseases. Animal models can be used to understand and evaluate the performance of materials in complex physiological environments, providing relevant data for preclinical evaluation of implants and laying the foundation for subsequent clinical studies. To date, many researchers have studied the biocompatibility, degradability and osteogenesis of magnesium-based materials, but there is a lack of review regarding the effects of magnesium-based materials in vivo. In view of the growing interest in these materials, this review briefly describes the properties of magnesium-based materials and focuses on the safety and efficacy of magnesium-based materials in vivo. Various animal models including rats, rabbits, dogs and pigs are covered to better understand and evaluate the progress and future of magnesium-based materials. This literature analysis reveals that the magnesium-based materials have good biocompatibility and osteogenic activity, thus causing no adverse reaction around the implants in vivo, and that they exhibit a beneficial effect in the process of bone repair. In addition, the degradation rate in vivo can also be improved by means of alloying and coating. These encouraging results show a promising future for the use of magnesium-based materials in musculoskeletal disorders.

Attitudes and perspectives of older adults on technologies for assessing frailty in home settings: a focus group study

BACKGROUND

The rapid development of technology such as sensors and artificial intelligence in recent years enables monitoring frailty criteria to assess frailty early and accurately from a remote location such as a home. However, research shows technologies being abandoned or rejected by users due to a lack of compatibility and consumer involvement in selecting their assistive technology devices. This study aims to understand older adults' perceptions and preferences of technologies that can potentially assess frailty at home.

METHODS

This study collected qualitative data through focus group meetings with 15 participants ages 65 and older. Researchers asked participants questions to achieve the goal of understanding their attitudes on the technologies. These questions include (1) the concerns or barriers of installing and using the presented technology in daily life at home, (2) the reasons participants like or dislike a particular technology, (3) what makes a specific technology more acceptable, and (4) participants' preferences in choosing technologies. Data were transcribed, coded and categorized, and finally synthesized to understand the attitudes towards presented technologies.

RESULTS

Three focus group sessions were conducted with five participants in each session. In the findings, the attitudes and perspectives of participants on the technologies for assessing frailty were categorized into four themes: (A) general attitude towards using the technologies, (B) conditions for accepting certain technologies, (C) existing living habits or patterns related to using the technologies, and (D) constructive suggestions related to the technologies.

CONCLUSIONS

Participants generally had positive attitudes towards allowing the technologies to be installed and used at their homes. They would accept some technologies if used under certain conditions. However, questions and concerns remain, such as concerns about privacy, functionality, and aesthetics. The study also found that older adults' living habits or patterns could affect the design and use of technology. Lastly, many valuable suggestions have been made by participants. These perspectives and insights can help improve the design and adoption of home-based frailty assessment technologies among older adults.

Dementia Care Apps for People with Dementia and Informal Caregivers: A Systematic Review Protocol

Dementia drastically impacts the quality of life (QOL) of both people living with dementia (PLwD) and their family caregivers. As dementia progresses and care needs escalate, the likelihood of institutionalization is increased, which is counter to the wishes of the majority of older adults and their family members. Dementia care apps can provide critical support and have the potential to improve the QOL of both PLwD and their family caregivers and reduce perceived caregivers' burden. However, there is a lack of understanding of the needs of both PLwD and their family caregivers related to dementia care apps. There is also a gap in understanding the privacy concerns in relation to the apps among older adults with dementia and their caregivers. As such, the main aims of this systematic review are to understand the landscape of dementia mobile apps targeting PLwD and their caregivers with respect to the features of the apps, usability testing, and the privacy and security aspects of the app from the perspective of both app developers/researchers and the end users (PLwD and family caregivers who provide care of PLwD). Extensive databases, including ACM Digital Library, Cochrane Central Register of Controlled Trials, Compendex, Embase, Inspec, Ovid MEDLINE(R) Daily, Proquest Dissertations and These Global, PsycINFO, and Scopus, have been searched. All searches are from the inception of the databases. All peer-reviewed studies and articles written in the English language are included. Two reviewers will independently screen and select the studies with the involvement of a third reviewer for disagreements. Data will be abstracted using a custom data extraction form that is made based on the research questions. Critical Appraisal Skills Programme (CASP) checklists will be used to assess the study quality. As the first review of its kind, the findings from this review will provide valuable insights related to the needs of the dementia care apps for both PLwD and their family caregivers. The review will be relevant to health providers who are interested in using technologies to promote the independence of PLwD and reduce the stress experienced from caregivers of PLwD. The review will also serve as a guide to app developers and researchers to design usable and acceptable apps. In addition, the review will provide critical knowledge of the privacy and security features of the app to reveal the valid concerns from the end users and thus help with the uptake and adoption of the dementia care apps.

A proof-of-concept study of an automated solution for clinical metagenomic next-generation sequencing

AIMS

Metagenomic next-generation sequencing (mNGS) has been utilized for diagnosing infectious diseases. It is a culture-free and hypothesis-free nucleic acid test for diagnosing all pathogens with known genomic sequences, including bacteria, fungi, viruses and parasites. While this technique greatly expands the clinical capacity of pathogen detection, it is a second-line choice due to lengthy procedures and microbial contaminations introduced from wet-lab processes. As a result, we aimed to reduce the hands-on time and exogenous contaminations in mNGS.

METHODS AND RESULTS

We developed a device (NGSmaster) that automates the wet-lab workflow, including nucleic acid extraction, PCR-free library preparation and purification. It shortens the sample-to-results time to 16 and 18·5 h for DNA and RNA sequencing respectively. We used it to test cultured bacteria for validation of the workflow and bioinformatic pipeline. We also compared PCR-free with PCR-based library prep and discovered no differences in microbial reads. Moreover we analysed results by automation and manual testing and found that automation can significantly reduce microbial contaminations. Finally, we tested artificial and clinical samples and showed mNGS results were concordant with traditional culture.

CONCLUSION

NGSmaster can fulfil the microbiological diagnostic needs in a variety of sample types.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study opens up an opportunity of performing in-house mNGS to reduce turnaround time and workload, instead of transferring potentially contagious specimen to a third-party laboratory.

Influence of Multiple Sclerosis on Spatiotemporal Gait Parameters: A Systematic Review and Meta-Regression

OBJECTIVE

To quantify the effect of multiple sclerosis (MS) on spatiotemporal gait characteristics accounting for disability severity and fall classification.

DATA SOURCES

MEDLINE (1946-August 2018), Allied and Complementary Medicine Database (1985-2018 August), and PsycINFO (1806-August 2018) were searched for terms on MS and gait.

STUDY SELECTION

Dual independent screening was conducted to identify observational, cross-sectional studies that compared adults with MS grouped according to Expanded Disability Status Scale (EDSS) level or fall history, reported on spatiotemporal gait characteristics, and were published in English. The search retrieved 5891 results, of which 12 studies satisfied the inclusion criteria.

DATA EXTRACTION

Two authors worked independently to extract and verify data on publication details, study methodology, participant characteristics, gait outcomes, conclusions, and limitations. Risk of bias was assessed using the QualSyst critical appraisal tool. A random-effects meta-regression and meta-analysis were conducted on pooled data.

DATA SYNTHESIS

All studies received quality ratings of very good to excellent and collectively examined 1513 individuals with MS. With every 1-point increase in EDSS, significant changes (P<.05) were observed in gait speed (-0.12 m/s; 95% confidence interval (CI), 0.08-0.15), step length (-0.04 m; 95% CI, 0.03-0.05), step time (+0.04 seconds; 95% CI, 0.02-0.06), step time variability (+0.009 seconds; 95% CI, 0.003-0.016), stride time (+0.08 seconds; 95% CI, 0.03-0.12), cadence (-4.4 steps per minute; 95% CI, 2.3-6.4), stance phase duration (+0.8% gait cycle; 95% CI, 0.1-1.5), and double support time (+3.5% gait cycle; 95% CI, 1.5-5.4). Recent fallers exhibited an 18% (95% CI, 13%-23%) reduction in gait speed compared with nonfallers (P<.001).

CONCLUSIONS

This review provides the most accurate reference values to-date that can be used to assess the effectiveness of MS gait training programs and therapeutic techniques for individuals who differ on disability severity and fall classification. Some gait adaptations could be part of adopting a more cautious gait strategy and should be factored into the design of future interventions.

A glycoconjugate-based gold nanoparticle approach for the targeted treatment of Pseudomonas aeruginosa biofilms

In this study, "core-shell" gold nanoparticles (AuNPs) have been functionalised using a simple one-pot approach to form fucose-based glycoconjugate AuNPs (Fuc-AuNPs) and galactose-based glycoconjugate AuNPs (Gal-AuNPs), respectively. Owing to the selective carbohydrate-based recognition of the key virulence factors of P. aeruginosa, LecB (fucose-specific lectin)/LecA (galactose-specific lectin), Fuc-AuNPs and Gal-AuNPs-based imaging and therapeutic strategies were evaluated towards P. aeruginosa. Both Fuc-AuNPs and Gal-AuNPs were non-covalently loaded with the fluorophore dicyanomethylene 4H-pyran (DCM) to afford two highly selective fluorescence imaging agents for the visualisation of P. aeruginosa. The loading of Fuc-AuNPs and Gal-AuNPs with the known antibiotic Ceftazidime (CAZ) exhibited an enhanced therapeutic effect, illustrating the significance of this targeted drug delivery strategy. Exploiting the phototherapeutic properties of AuNPs, photoirradiation (600 nm) of Fuc-AuNP@CAZ/Gal-AuNP@CAZ provided both photothermal and photodynamic therapeutic (PTT/PDT) effects, which facilitated the release of CAZ. Fuc-AuNP@CAZ and Gal-AuNP@CAZ were shown to be effective photo/chemotherapeutics resulting in almost complete eradication of P. aeruginosa biofilms formed on clinically relevant surfaces (glass slides and steel surface).

[Advances in research on aquaporins in medical helminthes]

Aquaporins (AQPs) are a class of membrane intrinsic proteins in medical helminthes that specifically mediate the transmembrane transport of water or other solute molecules. Previous studies have demonstrated that AQPs play a critical role in promoting the transmembrane transport of water, osmoregulation, uptake of nutrients, release of toxic metabolic products and transport of antiparasitic drugs, which may serve as promising vaccine candidates and drug targets for parasitic diseases. This review describes the structural characteristics of AQPs in medical helminthes, and discusses the feasibility of these AQPs as antihelminth vaccine candidates and drug targets, so as to provide insights into the development of novel vaccines and drugs against parasitic diseases.

[Advances in research of protein kinase A in parasites: a review]

Protein kinase A (PKA) is an important intracellular substance that regulates substance metabolism and biological functions, which exerts a wide range of biological effects through phosphorylation of specific serine/threonine residues in specific proteins. PKA plays an important role in the cAMP signaling pathway, and is involved in various life activities of parasites. Therefore, investigating the role of PKA in the life activities of parasites may provide insights into the development of novel anti-parasitic targets. The review mainly describes the structure and function of PKA and its role in life activities of parasites.

Protective effects of Lactobacillus plantarum strain P1 against toxicity of the environmental oestrogen di-n-butyl phthalate in rats

Phthalates are contaminants widely distributed in the food-chain, and they are considered as important environmental oestrogens in our lives. In the present study, eight strains of lactic acid bacteria were isolated for their ability to adsorb di-n-butyl-phthalate (DBP), and one of the strains, Lactobacillus plantarum strain P1, was selected for more detailed analyses of its phthalate adsorption capacity in vitro. This study also evaluated the in vivo protective effects of strain P1 against DBP toxicity in rats. Sixteen rats were divided into four groups, and animals received by oral gavage every other day for a period of one month saline with or without strain P1 at 2×10¹¹ cfu/kg followed by maize oil with or without DBP (50 mg/kg). Strain P1 could adsorb more DBP than saline alone, and the concentration of mono-n-butyl phthalate in urine was decreased in animals receiving P1. Furthermore, oestrogenic effects of the different treatments were assessed through counting of sperm and observation of testis, and strain P1 could protect the sexual organs of male rats. Our results suggested that P1 is effective against phthalate toxicity due to its ability to adsorb DBP in vivo and could be considered as a new dietary therapeutic strategy against environmental phtalate toxicity.