Wide bandgap semiconductor nanomembranes as a long-term biointerface for flexible, implanted neuromodulator.

Electrical neuron stimulation holds promise for treating chronic neurological disorders, including spinal cord injury, epilepsy, and Parkinson's disease. The implementation of ultrathin, flexible electrodes that can offer noninvasive attachment to soft neural tissues is a breakthrough for timely, continuous, programable, and spatial stimulations. With strict flexibility requirements in neural implanted stimulations, the use of conventional thick and bulky packages is no longer applicable, posing major technical issues such as short device lifetime and long-term stability. We introduce herein a concept of long-lived flexible neural electrodes using silicon carbide (SiC) nanomembranes as a faradic interface and thermal oxide thin films as an electrical barrier layer. The SiC nanomembranes were developed using a chemical vapor deposition (CVD) process at the wafer level, and thermal oxide was grown using a high-quality wet oxidation technique. The proposed material developments are highly scalable and compatible with MEMS technologies, facilitating the mass production of long-lived implanted bioelectrodes. Our experimental results showed excellent stability of the SiC/silicon dioxide (SiO2) bioelectronic system that can potentially last for several decades with well-maintained electronic properties in biofluid environments. We demonstrated the capability of the proposed material system for peripheral nerve stimulation in an animal model, showing muscle contraction responses comparable to those of a standard non-implanted nerve stimulation device. The design concept, scalable fabrication approach, and multimodal functionalities of SiC/SiO2 flexible electronics offer an exciting possibility for fundamental neuroscience studies, as well as for neural stimulation-based therapies.

Nanopore Blockade Sensors for Quantitative Analysis Using an Optical Nanopore Assay.

Nanopore sensing is a popular biosensing strategy that is being explored for the quantitative analysis of biomarkers. With low concentrations of analytes, nanopore sensors face challenges related to slow response times and selectivity. Here, we demonstrate an approach to rapidly detect species at ultralow concentrations using an optical nanopore blockade sensor for quantitative detection of the protein vascular endothelial growth factor (VEGF). This sensor relies on monitoring fluorescent polystyrene nanoparticles blocking nanopores in a nanopore array of 676 nanopores. The fluorescent signal is read out using a wide-field fluorescence microscope. Nonspecific blockade events are then distinguished from specific blockade events based on the ability to pull the particles out of the pore using an applied electric field. This allows the detection of VEGF at sub-picomolar concentration in less than 15 min.

Integrated Sensors for Soft Medical Robotics.

Minimally invasive procedures assisted by soft robots for surgery, diagnostics, and drug delivery have unprecedented benefits over traditional solutions from both patient and surgeon perspectives. However, the translation of such technology into commercialization remains challenging. The lack of perception abilities is one of the obstructive factors paramount for a safe, accurate and efficient robot-assisted intervention. Integrating different types of miniature sensors onto robotic end-effectors is a promising trend to compensate for the perceptual deficiencies in soft robots. For example, haptic feedback with force sensors helps surgeons to control the interaction force at the tool-tissue interface, impedance sensing of tissue electrical properties can be used for tumor detection. The last decade has witnessed significant progress in the development of multimodal sensors built on the advancement in engineering, material science and scalable micromachining technologies. This review article provides a snapshot on common types of integrated sensors for soft medical robots. It covers various sensing mechanisms, examples for practical and clinical applications, standard manufacturing processes, as well as insights on emerging engineering routes for the fabrication of novel and high-performing sensing devices.

The synthesis and properties of Ca3 Sc2 Si3 O12 :Ce3+ (CSSG) phosphor are utilized for the development of human-centric lighting light-emitting diodes (HCL-LEDs).

In this study, cerium ion (Ce3+ )-doped calcium scandium silicate garnet (Ca3 Sc2 Si3 O12 , abbreviated CSSG) phosphors were successfully synthesized using the sol-gel method. The crystal phase, morphology, and photoluminescence properties of the synthesized phosphors were thoroughly investigated. Under excitation by a blue light-emitting diode (LED) chip (450 nm), the CSSG phosphor displayed a wide emission spectrum spanning from green to yellow. Remarkably, the material exhibited exceptional thermal stability, with an emissivity ratio at 150°C to that at 25°C reaching approximately 85%. Additionally, the material showcased impressive optical performance when tested with a blue LED chip, including a color rendering index (CRI) exceeding 90, an R9 value surpassing 50, and a biological impact ratio (M/P) above 0.6. These noteworthy findings underscore the potential applications of CSSG as a white light-converting phosphor, particularly in the realm of human-centered lighting.

Presence of Functionally Active Cytolethal Distending Toxin Genes on a Conjugative Plasmid in a Clinical Isolate of Providencia rustigianii.

Providencia rustigianii is potentially enteropathogenic in humans. Recently, we identified a P. rustigianii strain carrying a part of the cdtB gene homologous to that of Providencia alcalifacines that produces an exotoxin called cytolethal distending toxin (CDT), encoded by three subunit genes (cdtA, cdtB, and cdtC). In this study, we analyzed the P. rustigianii strain for possible presence of the entire cdt gene cluster and its organization, location, and mobility, as well as expression of the toxin as a putative virulence factor of P. rustigianii. Nucleotide sequence analysis revealed the presence of the three cdt subunit genes in tandem, and over 94% homology to the corresponding genes carried by P. alcalifaciens both at nucleotide and amino acid sequence levels. The P. rustigianii strain produced biologically active CDT, which caused distension of eukaryotic cell lines with characteristic tropism of CHO and Caco-2 cells but not of Vero cells. S1-nuclease digested pulsed-field gel electrophoresis followed by Southern hybridization analysis demonstrated that the cdt genes in both P. rustigianii and P. alcalifaciens strains are located on large plasmids (140 to 170 kb). Subsequently, conjugation assays using a genetically marked derivative of the P. rustigianii strain showed that the plasmid carrying cdt genes in the P. rustigianii was transferable to cdt gene-negative recipient strains of P. rustigianii, Providencia rettgeri, and Escherichia coli. Our results demonstrated the presence of cdt genes in P. rustigianii for the first time, and further showed that the genes are located on a transferable plasmid, which can potentially spread to other bacterial species.

Mesoporous Metastable CuTe2 Semiconductor.

Binary metastable semiconductor materials offer exciting possibilities in the field of optoelectronics, such as photovoltaics, tunable photosensors, and detectors. However, understanding their properties and translating them into practical applications can sometimes be challenging, owing to their thermodynamic instability. Herein, we report a temperature-controlled crystallization technique involving electrochemical deposition to produce metastable CuTe2 thin films that can reliably function under ambient conditions. A series of in situ heating/cooling cycle tests from room temperature to 200 °C followed by spectral, morphological, and compound analyses (such as ultraviolet-visible light spectroscopy, X-ray diffraction (XRD) analysis, and X-ray photoelectron spectroscopy (XPS)) suggest that the seeding electrodes play a key role in the realization of the metastable phase in CuTe2 films. In particular, CuTe2 films deposited on Al electrodes exhibit superior crystallinity and long-term stability compared with those grown on a Au substrate. The XRD data of thermally annealed CuTe2 thin films deposited on Al show a markedly sharp peak, indicating significantly increased crystal-domain sizes. Our method can be used to achieve the metastable phase of CuTe2 with a bandgap of 1.67 eV and offers outstanding photoresponsivity under different illumination conditions.

Flexible Nanoarchitectonics for Biosensing and Physiological Monitoring Applications.

Flexible and implantable electronics hold tremendous promises for advanced healthcare applications, especially for physiological neural recording and modulations. Key requirements in neural interfaces include miniature dimensions for spatial physiological mapping and low impedance for recognizing small biopotential signals. Herein, a bottom-up mesoporous formation technique and a top-down microlithography process are integrated to create flexible and low-impedance mesoporous gold (Au) electrodes for biosensing and bioimplant applications. The mesoporous architectures developed on a thin and soft polymeric substrate provide excellent mechanical flexibility and stable electrical characteristics capable of sustaining multiple bending cycles. The large surface areas formed within the mesoporous network allow for high current density transfer in standard electrolytes, highly suitable for biological sensing applications as demonstrated in glucose sensors with an excellent detection limit of 1.95 µm and high sensitivity of 6.1 mA cm-2  µM-1 , which is approximately six times higher than that of benchmarking flat/non-porous films. The low impedance of less than 1 kΩ at 1 kHz in the as-synthesized mesoporous electrodes, along with their mechanical flexibility and durability, offer peripheral nerve recording functionalities that are successfully demonstrated in vivo. These features highlight the new possibilities of our novel flexible nanoarchitectonics for neuronal recording and modulation applications.

The density of bone marrow mononuclear cells and CD34+ cells in patients with three neurologic conditions.

BACKGROUND: This study aimed to identify the density of mononuclear cells (MNCs) and CD34+ cells in the bone marrow of patients with three neurologic conditions. METHODS: The study included 88 patients with three neurologic conditions: 40 with cerebral palsy (CP) due to oxygen deprivation (OD), 23 with CP related to neonatal icterus (NI), and 25 with neurological sequelae after traumatic brain injury. Bone marrow aspiration was conducted from the patients' bilateral anterior iliac crest under general anesthesia in an operating theater. MNCs were isolated by Ficoll gradient centrifugation and then infused intrathecally. RESULTS: There was a significant difference in the average MNC per ml and percentage of CD34+ cells by the type of disease, age group, and infusion time (p value < 0.05). The multivariable regression model showed the percentage of CD34+ association with the outcome (gross motor function 88 items- GMFM-88) in patients with CP. CONCLUSIONS: The density of MNCs was 5.22 million cells per mL and 5.03% CD34+ cells in patients with three neurologic conditions. The highest density of MNCs in each ml of bone marrow was found in patients with CP due to OD, whereas the percentage of CD34+ cells was the highest among patients with CP related to NI.

Postpartum depression in Vietnam: a scoping review of symptoms, consequences, and management.

BACKGROUND: Postpartum depression (PPD) is a major health issue that can affect both mothers and their newborn children. In Vietnam, approximately 20% of mothers suffer from PPD. However, there is a lack of synthesized evidence regarding the case management of PPD in the Vietnamese context. A review of early symptoms, consequences, and management strategies of PPD will help to inform best practices to reduce complications and shorten the recovery time after parturition. METHODS: This scoping review aims to analyze and synthesize the findings of studies on PPD examining the symptoms, consequences, and management strategies among Vietnamese women. MEDLINE, CINAHL, PubMed, ScienceDirect, EBSCOHost, Google Scholar, and a networked digital library of projects, theses, and dissertations published between 2010 and 2022 in Vietnam were accessed following search terms including "Vietnam", "depression", "postpartum", "symptom/experience", "consequence", and "management". FINDINGS: The most-reported symptoms were sadness, tiredness, the feeling of being ignored, lack of interest in the baby, reduced appetite, and sleep disturbance. The recognized consequences were child stunting and slow growth, without mentioning its long-term effects on mothers. Our findings indicated that PPD in Vietnam has not been sufficiently managed; mothers tend to seek help from 'fortune-tellers' or 'word-of-mouth' practices rather than from evidence-based modern medicine. CONCLUSION: This scoping review provides an initial stage of PPD symptoms, consequences, and management along with facilitating an interventional program to support this vulnerable group of women. A large survey of Vietnamese mothers' symptoms, effects, and management strategies is needed.

Atypical Presentations of Extraparenchymal Neurocysticercosis.

BACKGROUND: Neurocysticercosis (NCC) is the most common parasitic infection of the central nervous system and is typically diagnosed through visualization of the cysts in the cerebral parenchyma by neuro-imaging. However, neuro-imaging may not detect extraparenchymal neurocysticercosis (EPNCC), which is a rare manifestation of the disease involving the subarachnoid, meningeal, and intraventricular spaces. We report 2 cases of extraparenchymal neurocysticercosis, and discuss the diagnostic challenges and management of this entity. METHODS: Two cases were identified through clinical records. RESULTS: Both patients had an insidious onset with slow progression of disease, and presented with papilledema and cerebrospinal fluid (CSF) eosinophilia. One case was diagnosed with spinal cord biopsy. The other was diagnosed with CSF serology and next-generation sequencing-based pathogen analysis. Both patients were treated with ventriculoperitoneal shunt, systemic antiparasitic agents, and immunosuppression. CONCLUSIONS: EPNCC is less common than parenchymal NCC. A high level of clinical suspicion is required given its rarity, long incubation period, and slow progression. Diagnosis and treatment can be challenging and requires a multidisciplinary approach.

Sharing health information across online platforms: A systematic review.

Advanced Web 2.0 communication technologies have facilitated health-related information (HRI) sharing on the Internet. Especially, the COVID-19 pandemic and lockdowns around the world have forced more people to turn to the Internet for HRI. A better understanding of users' sharing content and sharing behavior can help communicators improve health literacy, raise community awareness, and facilitate social support exchanges. This paper reports the results of a systematic review of online HRI sharing literature, including key research topics, theories and methods used in past studies, and key factors of sharing behavior across online platforms. Following the PRISMA procedure for a systematic review, 58 articles were identified and analyzed using keyword matching, thematic analysis, and expert review. Guided by the platform theory, our findings differentiated five types of online platforms that differently influenced online users' sharing content and sharing purposes, including micro-blogs, social network sites, online health communities, social question and answer sites, and Wikis. The findings also clarify five main research topics and applicable theories used in each topic, including personal health sharing, health-related knowledge sharing, general health message diffusion, outcomes of HRI sharing, and exploratory research. Key factors of sharing behavior and potential sharing outcomes are also reviewed and summarized in the research framework developed from the motivation theory. Our study contributes to the understanding of online sharing behavior and provides implications for health communicators to develop effective health campaigns. Potential research directions are also identified and discussed.

Experiences and perceptions of dementia in Vietnam and among the Vietnamese diaspora: a systematic review of qualitative studies.

Objectives: This paper aimed to review and synthesise the qualitative research evidence on the experiences and perceptions of dementia in Vietnam and among the Vietnamese diaspora.Methods: Systematic searches were conducted in June 2019 using Medline, Embase, Emcare, PsycINFO and Cochrane electronic databases, as well as grey literature. Keywords and Medical Subject Headings [MeSH terms] for dementia and associated terms were combined with keywords for Vietnam and its provinces. Qualitative research articles published in English or Vietnamese were included to examine evidence on the life experiences of Vietnamese people with dementia using thematic analysis.Results: Our searches resulted in 3,940 papers, from which 21 qualitative research studies were included for final analysis. The majority of research has not been undertaken in Vietnam but with the Vietnamese diaspora in Western countries and has taken a cultural perspective to analyses. Research in Western countries has focused on the need for culturally adapted and culturally sensitive models of care. Emerging themes about the life experiences of Vietnamese people with dementia identified from the studies included: many people do not have diagnostic terms for dementia but use the descriptive language of symptoms; stigma was a reported problem and on occasions can be observed in the descriptive language used for people with dementia; cultural and traditional values create both an opportunity and a barrier, supporting compassion, family care and relaxation, but creating barriers to accessing health services or long-term residential care.Conclusions: This is the first systematic review reporting qualitative evidence on the life experiences of people with dementia in Vietnam and among the Vietnamese diaspora. Future research is needed on the voice of people with dementia themselves and their caregivers particularly in Vietnam, and low and middle-income countries with regards to living with dementia, pathways to care from diagnosis, treatment, care and support, additional social care and preparedness for end of life care for people with dementia.

Transparent Pneumatic Tactile Sensors for Soft Biomedical Robotics.

Palpation is a simple but effective method to distinguish tumors from healthy tissues. The development of miniaturized tactile sensors embedded on endoscopic or robotic devices is key to achieving precise palpation diagnosis and subsequent timely treatment. This paper reports on the fabrication and characterization of a novel tactile sensor with mechanical flexibility and optical transparency that can be easily mounted on soft surgical endoscopes and robotics. By utilizing the pneumatic sensing mechanism, the sensor offers a high sensitivity of 1.25 mbar and negligible hysteresis, enabling the detection of phantom tissues with different stiffnesses ranging from 0 to 2.5 MPa. Our configuration, combining pneumatic sensing and hydraulic actuating, also eliminates electrical wiring from the functional elements located at the robot end-effector, thereby enhancing the system safety. The optical transparency path in the sensors together with its mechanical sensing capability open interesting possibilities in the early detection of solid tumor as well as in the development of all-in-one soft surgical robots that can perform visual/mechanical feedback and optical therapy.

A Smart, Textile-Driven, Soft Exosuit for Spinal Assistance.

Work-related musculoskeletal disorders (WMSDs) are often caused by repetitive lifting, making them a significant concern in occupational health. Although wearable assist devices have become the norm for mitigating the risk of back pain, most spinal assist devices still possess a partially rigid structure that impacts the user's comfort and flexibility. This paper addresses this issue by presenting a smart textile-actuated spine assistance robotic exosuit (SARE), which can conform to the back seamlessly without impeding the user's movement and is incredibly lightweight. To detect strain on the spine and to control the smart textile automatically, a soft knitting sensor that utilizes fluid pressure as a sensing element is used. Based on the soft knitting hydraulic sensor, the robotic exosuit can also feature the ability of monitoring and rectifying human posture. The SARE is validated experimentally with human subjects (N = 4). Through wearing the SARE in stoop lifting, the peak electromyography (EMG) signals of the lumbar erector spinae are reduced by 22.8% ± 12 for lifting 5 kg weights and 27.1% ± 14 in empty-handed conditions. Moreover, the integrated EMG decreased by 34.7% ± 11.8 for lifting 5 kg weights and 36% ± 13.3 in empty-handed conditions. In summary, the artificial muscle wearable device represents an anatomical solution to reduce the risk of muscle strain, metabolic energy cost and back pain associated with repetitive lifting tasks.

The Correlation between Peripheral Blood Index and Immune Cell Expansion in Vietnamese Elderly Lung Cancer Patients.

(1) Background: The dysfunction and reduced proliferation of peripheral CD8+ T cells and natural killer (NK) cells have been observed in both aging and cancer patients, thereby challenging the adoption of immune cell therapy in these subjects. In this study, we evaluated the growth of these lymphocytes in elderly cancer patients and the correlation of peripheral blood (PB) indices to their expansion. (2) Method: This retrospective study included 15 lung cancer patients who underwent autologous NK cell and CD8+ T cell therapy between January 2016 and December 2019 and 10 healthy individuals. (3) Results: On average, CD8+ T lymphocytes and NK cells were able to be expanded about 500 times from the PB of elderly lung cancer subjects. Particularly, 95% of the expanded NK cells highly expressed the CD56 marker. The expansion of CD8+ T cells was inversely associated with the CD4+:CD8+ ratio and the frequency of PB-CD4+ T cells in PB. Likewise, the expansion of NK cells was inversely correlated with the frequency of PB-lymphocytes and the number of PB-CD8+ T cells. The growth of CD8+ T cells and NK cells was also inversely correlated with the percentage and number of PB-NK cells. (4) Conclusion: PB indices are intrinsically tied to immune cell health and could be leveraged to determine CD8 T and NK cell proliferation capacity for immune therapies in lung cancer patients.

Barriers to COVID-19 contact tracing: View from frontline healthcare students in Vietnam.

In the context of the complicated continuous waves of the COVID-19 pandemic in Vietnam, contact tracing, along with social distancing and lock-down, proved its crucial role in the suppression of epidemic spreading and management. With the high demand for responsiveness, healthcare students were constantly involved in the process, and challenges have emerged along the way. This study aims to identify the barriers faced by healthcare students while performing the contact tracing task at the frontline of the pandemic. A qualitative study was conducted in July 2021 in a health center in Binh Duong province, Vietnam. A total of 20 healthcare students were invited through random recruitment of participants and interviewed until the principle of saturation was reached. Three main barriers were identified including ineffective work management of local managers, lack of capability of human resources and facilities, and uncooperative attitude of local residents. Given the existing barriers, cooperative, innovative strategies, shared data systems, and timely public awareness campaigns, especially among primary health centers of the healthcare system, are imperative to reduce the workload and optimize the efficacy of healthcare students' support.

iPromoter-Seqvec: identifying promoters using bidirectional long short-term memory and sequence-embedded features.

BACKGROUND: Promoters, non-coding DNA sequences located at upstream regions of the transcription start site of genes/gene clusters, are essential regulatory elements for the initiation and regulation of transcriptional processes. Furthermore, identifying promoters in DNA sequences and genomes significantly contributes to discovering entire structures of genes of interest. Therefore, exploration of promoter regions is one of the most imperative topics in molecular genetics and biology. Besides experimental techniques, computational methods have been developed to predict promoters. In this study, we propose iPromoter-Seqvec - an efficient computational model to predict TATA and non-TATA promoters in human and mouse genomes using bidirectional long short-term memory neural networks in combination with sequence-embedded features extracted from input sequences. The promoter and non-promoter sequences were retrieved from the Eukaryotic Promoter database and then were refined to create four benchmark datasets. RESULTS: The area under the receiver operating characteristic curve (AUCROC) and the area under the precision-recall curve (AUCPR) were used as two key metrics to evaluate model performance. Results on independent test sets showed that iPromoter-Seqvec outperformed other state-of-the-art methods with AUCROC values ranging from 0.85 to 0.99 and AUCPR values ranging from 0.86 to 0.99. Models predicting TATA promoters in both species had slightly higher predictive power compared to those predicting non-TATA promoters. With a novel idea of constructing artificial non-promoter sequences based on promoter sequences, our models were able to learn highly specific characteristics discriminating promoters from non-promoters to improve predictive efficiency. CONCLUSIONS: iPromoter-Seqvec is a stable and robust model for predicting both TATA and non-TATA promoters in human and mouse genomes. Our proposed method was also deployed as an online web server with a user-friendly interface to support research communities. Links to our source codes and web server are available at https://github.com/mldlproject/2022-iPromoter-Seqvec .

Limitation of current probe design for oligo-cross-FISH, exemplified by chromosome evolution studies in duckweeds.

Duckweeds represent a small, free-floating aquatic family (Lemnaceae) of the monocot order Alismatales with the fastest growth rate among flowering plants. They comprise five genera (Spirodela, Landoltia, Lemna, Wolffiella, and Wolffia) varying in genome size and chromosome number. Spirodela polyrhiza had the first sequenced duckweed genome. Cytogenetic maps are available for both species of the genus Spirodela (S. polyrhiza and S. intermedia). However, elucidation of chromosome homeology and evolutionary chromosome rearrangements by cross-FISH using Spirodela BAC probes to species of other duckweed genera has not been successful so far. We investigated the potential of chromosome-specific oligo-FISH probes to address these topics. We designed oligo-FISH probes specific for one S. intermedia and one S. polyrhiza chromosome (Fig. 1a). Our results show that these oligo-probes cross-hybridize with the homeologous regions of the other congeneric species, but are not suitable to uncover chromosomal homeology across duckweeds genera. This is most likely due to too low sequence similarity between the investigated genera and/or too low probe density on the target genomes. Finally, we suggest genus-specific design of oligo-probes to elucidate chromosome evolution across duckweed genera.

Engineering Stress in Thin Films: An Innovative Pathway Toward 3D Micro and Nanosystems.

Transformation of conventional 2D platforms into unusual 3D configurations provides exciting opportunities for sensors, electronics, optical devices, and biological systems. Engineering material properties or controlling and modulating stresses in thin films to pop-up 3D structures out of standard planar surfaces has been a highly active research topic over the last decade. Implementation of 3D micro and nanoarchitectures enables unprecedented functionalities including multiplexed, monolithic mechanical sensors, vertical integration of electronics components, and recording of neuron activities in 3D organoids. This paper provides an overview on stress engineering approaches to developing 3D functional microsystems. The paper systematically presents the origin of stresses generated in thin films and methods to transform a 2D design into an out-of-plane configuration. Different types of 3D micro and nanostructures, along with their applications in several areas are discussed. The paper concludes with current technical challenges and potential approaches and applications of this fast-growing research direction.

Hydrogel Nanoarchitectonics: An Evolving Paradigm for Ultrasensitive Biosensing.

The integration of nanoarchitectonics and hydrogel into conventional biosensing platforms offers the opportunities to design physically and chemically controlled and optimized soft structures with superior biocompatibility, better immobilization of biomolecules, and specific and sensitive biosensor design. The physical and chemical properties of 3D hydrogel structures can be modified by integrating with nanostructures. Such modifications can enhance their responsiveness to mechanical, optical, thermal, magnetic, and electric stimuli, which in turn can enhance the practicality of biosensors in clinical settings. This review describes the synthesis and kinetics of gel networks and exploitation of nanostructure-integrated hydrogels in biosensing. With an emphasis on different integration strategies of hydrogel with nanostructures, this review highlights the importance of hydrogel nanostructures as one of the most favorable candidates for developing ultrasensitive biosensors. Moreover, hydrogel nanoarchitectonics are also portrayed as a promising candidate for fabricating next-generation robust biosensors.