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Abstract Epiretinal prostheses aim at electrically stimulating the inner most surviving retinal cells—retinal ganglion cells (RGCs)—to restore partial sight to the blind. Recent tests in patients with epiretinal implants have revealed that electrical stimulation of the retina results in the percept of color of the elicited phosphenes, which depends on the frequency of stimulation. This paper presents computational results that are predictive of this finding and further support our understanding of the mechanisms of color encoding in electrical stimulation of retina, which could prove pivotal for the design of advanced retinal prosthetics that elicit both percept and color. This provides, for the first time, a directly applicable “amplitude-frequency” stimulation strategy to “encode color” in future retinal prosthetics through a predictive computational tool to selectively target small bistratified cells, which have been shown to contribute to “blue-yellow” color opponency in the retinal circuitry. The presented results are validated with experimental data reported in the literature and correlated with findings in blind patients with a retinal prosthetic implant collected by our group.

A chitosan/deoxyribonucleic acid (CHI/DNA)5 coating was constructed by layer-by-layer (LbL) assembly dip coating method with Mg(OH)2 coating as an inner protective layer on AZ31 alloy. X-ray diffractometry, X-ray photoelectron spectrometry, Fourier transform infrared spectroscopy and field-emission scanning electron microscopy were utilized to represent the chemical compositions and surface morphologies of the coatings. Electrochemical tests and hydrogen evolution measurements were implemented to confirm the good corrosion resistance of the composite coating in artificial body fluid. Antimicrobial activity of the composite coatings was tested via the plate-counting method, and the cytotoxicity of the samples was appraised by MTT assay and Live/dead staining. A double action was put into effect for the composite coating, which the inner Mg(OH)2 coating plays the part of physical barrier, and the outer (CHI/DNA)5 coating is employed as an inducer to fabricate a biocompatible Ca-P corrosion product coating during immersion, making up for its thin thickness. Otherwise, the composite coating is also beneficial for the growth of bone, resulting from the biomineralization effect of the outer polyelectrolyte multilayer. The good antibacterial property of the (CHI/DNA)5/Mg(OH)2 coating is ascribed to the contact-killing strength of CHI. Thus, the obtained (CHI/DNA)5/Mg(OH)2 coating has a wide application prospect in the field of Mg-based bone implantation.

Dual tasks (DTs) combining walking with a cognitive task can cause various levels of cognitive–motor interference, depending on which brain resources are recruited in each case. However, the brain activation and functional connectivity underlying cognitive–motor interferences remain to be elucidated. Therefore, this study investigated the neural correlation during different DT conditions in 40 healthy young adults (mean age: 27.53 years, 28 women). The DTs included walking during subtraction or N‐Back tasks. Cognitive–motor interference was calculated, and brain activation and functional connectivity were analysed. Portable functional near‐infrared spectroscopy was utilized to monitor haemodynamics in the prefrontal cortex (PFC), motor cortex and parietal cortex during each task. Walking interference (decrease in walking speed during DT) was greater than cognitive interference (decrease in cognitive performance during DT), regardless of the type of task. Brain activation in the bilateral PFC and parietal cortex was greater for walking during subtraction than for standing subtraction. Furthermore, brain activation was higher in the bilateral motor and parietal and PFCs for walking during subtraction than for walking alone, but only increased in the PFC for walking during N‐Back. Coherence between the bilateral lateral PFC and between the left lateral PFC and left motor cortex was significantly greater for walking during 2‐Back than for walking. The PFC, a critical brain region for organizing cognitive and motor functions, played a crucial role in integrating information coming from multiple brain networks required for completing DTs. Therefore, the PFC could be a potential target for the modulation and improvement of cognitive–motor functions during neurorehabilitation. [ABSTRACT FROM AUTHOR]

Modern oncology increasingly relies on pathological, molecular, and genomic assessments of biopsied tumor tissue. However, the concern for bleeding complication and malignant seeding severely hinders the application of the biopsy tumor. Here, we developed a 16 G biopsy needle to contain two electrodes insulated from each other and connect to an radiofrequency generator. For evaluating hemostatic efficacy, 50 rabbits were randomly divided into two groups: warfarinization and non-warfarinization group. Two liver biopsies and two splenic biopsies per animal were performed using a 16 G biopsy needle. Each group was further equally divided into five groups according to different hemostatic measures, including non-intervention, embolization using an absorbable gelatin sponge, and ablation by RF with three different needle temperatures (50°C, 70°C, and 90°C). Than, we used VX2 rabbit models (n = 25) and applied the five analogous biopsies to the tumor. The flush fluid from the biopsy needle underwent cytomorphological analysis. Our results that the groups using ablation by RF showed significantly less blood loss than the control group for liver and spleen in both groups (P < 0.001). After RF ablation, thermal coagulation of the tissue surrounding the needle tract was observed on both the macroscopic and histological level. Cytological smears showed that tumor cells were degenerated after RF at 70°C and 90°C. Our findings showed that bipolar RF biopsy needle is a promising tool for reducing hemorrhage after biopsy and avoiding implanting tumor cells in the tract.

The biocorrosion of magnesium in the external physiological environment is still difficult to accurately evaluate the degradation behavior in vivo, particularly, in the microenvironment of the patients with hyperglycemia or diabetes. Thus, we explored the synergistic effects of glucose and protein on the biodegradation of pure magnesium, so as to have a deeper understanding the mechanism of the degradation in vivo. The surface morphology and corrosion product composition of pure magnesium were investigated using SEM, EDS, FTIR, XRD and XPS. The effect of glucose and albumin on the degradation rate of pure magnesium was investigated via electrochemical and immersion tests. The adsorption of glucose and albumin on the sample surface was observed using fluorescence microscopy. The results showed that the presence of 2 g/L glucose changed the micromorphology of corrosion products on the magnesium surface by reacting with metal cations, thus inhibiting the corrosion of pure magnesium. Protein formed a barrier layer to protect the magnesium at early stage of immersion. The chelation reaction between protein and magnesium surface might accelerate the degradation at later stage. There may be a critical glucose (albumin) content. Biodegradation of pure magnesium was inhibited at low concentrations and promoted at high concentrations. The synergistic effect of glucose and protein restrained the adsorption of aggressive chloride ions to a certain extent, and thus inhibited the degradation of pure magnesium considerably. Moreover, XPS results indicated that glucose promoted the adsorption of protein on the sample surface.

Micro-arc oxidation (MAO) coating with outstanding adhesion strength to Mg alloys has attracted more and more attention. However, owing to the porous structure, aggressive ions easily invaded the MAO/substrate interface through the through pores, limiting long-term corrosion resistance. Therefore, a dense and biocompatible tantalum oxide (Ta2O5) nanofilm was deposited on MAO coated Mg alloy AZ31 through atomic layer deposition (ALD) technique to seal the micropores and regulate the degradation rate. Surface micrography, chemical compositions and crystallographic structure were characterized using FE-SEM, EDS, XPS and XRD. The corrosion resistance of all samples was evaluated through electrochemical and hydrogen evolution tests. Results revealed that the Ta2O5 film mainly existed in the form of amorphousness. Moreover, uniform deposition of Ta2O5 film and effective sealing of micropores and microcracks in MAO coating were achieved. The current density (icorr) of the composite coating decreased three orders of magnitude than that of the substrate and MAO coating, improving corrosion resistance. Besides, the formation and corrosion resistance mechanisms of the composite coating were proposed. Keywords: Magnesium alloys, Micro-arc oxidation, Atomic layer deposition, Coatings

Biodegradable magnesium (Mg)-based alloys have aroused great concern owing to their promising characteristics as temporary implants for orthopedic application. But their undesirably rapid corrosion rate under physiological conditions has limited the actual clinical application. This study reports the use of a novel biomimetic polyelectrolyte multilayer template, based on polyvinylpyrrolidone (PVP) and polyacrylic acid (PAA) via layer-by-layer (LbL) assembly, to improve the corrosion resistance of the alloy. Surface characterization techniques (field-emission scanning electron microscopy, Fourier transform infrared (FTIR) spectrophotometer and X-ray diffractometer) confirmed the formation of biomineralized Ca–P coating on AZ31 alloy. Both hydrogen evolution and electrochemical corrosion tests demonstrated that the corrosion protection of the polyelectrolyte-induced Ca–P coating on AZ31 alloy. The formation mechanism of biomineralized Ca–P coating was proposed. Keywords: Magnesium alloy, Layer-by-layer assembly, Biomineralization, Calcium phosphate, Coating, Corrosion

Diabetic nephropathy (DN), a common microvascular complication of diabetes, is one of the main causes of end-stage renal failure (ESRD) and imposes a heavy medical burden on the world. Yiqi Jiedu Huayu decoction (YJHD) is a traditional Chinese medicine formula, which has been widely used in the treatment of DN and has achieved stable and reliable therapeutic effects. However, the mechanism of YJHD in the treatment of DN remains unclear. This study aimed to investigate the mechanism of YJHD in the treatment of DN. Sprague-Dawley rats were randomly divided into a normal control group, a diabetic group, an irbesartan group, and three groups receiving different doses of YJHD. Animal models were constructed using streptozotocin and then treated with YJHD for 12 consecutive weeks. Blood and urine samples were collected during this period, and metabolic and renal function was assessed. Pathological kidney injury was evaluated according to the kidney appearance, hematoxylin-eosin staining, Masson staining, periodic-acid Schiff staining, periodic-acid Schiff methenamine staining, and transmission electron microscopy. The expression levels of proteins and genes were detected by immunohistochemistry, western blotting, and real-time qPCR. Our results indicate that YJHD can effectively improve renal function and alleviate renal pathological injury, including mesangial matrix hyperplasia, basement membrane thickening, and fibrosis. In addition, YJHD exhibited podocyte protection by alleviating podocyte depletion and morphological damage, which may be key in improving renal function and reducing renal fibrosis. Further study revealed that YJHD upregulated the expression of the autophagy-related proteins LC3II and Beclin-1 while downregulating p62 expression, suggesting that YJHD can promote autophagy. In addition, we evaluated the activity of the mTOR pathway, the major signaling pathway regulating the level of autophagy, and the upstream PI3K/Akt and AMPK pathways. YJHD activated the AMPK pathway while inhibiting the PI3K/Akt and mTOR pathways, which may be crucial to its promotion of autophagy. In conclusion, our study shows that YJHD further inhibits the mTOR pathway and promotes autophagy by regulating the activity of the PI3K/Akt and AMPK pathways, thereby improving podocyte injury, protecting renal function, and reducing renal fibrosis. This study provides support for the application of and further research into YJHD.

The COVID-19 pandemic has highlighted the growing role of telemedicine in home dialysis treatments. Since the appearance of a connected automated peritoneal dialysis (APD) machine (Claria Sharesource Baxter® machine), we have systematically offered this solution to our patients treated with APD. Over the past two years, we have treated 35 patients with connected APD, of which 20 are still under the technique (aged 50 to 87) and represent 54% of the patients on peritoneal dialysis. A questionnaire on five subjects (perception of switching to the connected machine, stress, safety, everyday life, and vacations) was also given to them and showed that 80% of the patients had no stress related to the telemonitoring, while 18 out of 20 patients (90%) felt safe. In 2020, we received 74 phone calls during on-call phone duty, including 42 calls for the 20 patients on connected APD, one all for a patient on normal APD, and 32 calls for 16 patients on continuous ambulatory peritoneal dialysis (CAPD). Handling errors concerned 42.85% of the calls, system errors concerned 4.76%, program validation concerned 7.14%, and connection problems concerned 9.52%. We were thus able to correct several problems remotely, such as drainage problems, weight gain, blood pressure imbalance, poor compliance, and connection problems. Thanks to the platform, we are notified daily of a possible problem. This saves the nurses time and allows them to deal with other issues. The way we educate patients and assist private nurses has not changed. Indeed, only the connection to the network as well as the entry of the weight and arterial pressure were added, and the disposables remained the same. Night or day, or in times of a health crisis, we can provide a rapid and targeted response to the patients’ questions, thanks to the platform.

Aims: Understanding the neural mechanisms underlying stroke recovery is critical to determine effective interventions for stroke rehabilitation. This study aims to systematically explore how recovery mechanisms post‐stroke differ between individuals with different levels of functional integrity of the ipsilesional corticomotor pathway and motor function. Methods: Eighty‐one stroke survivors and 15 age‐matched healthy adults participated in this study. We used transcranial magnetic stimulation (TMS), electroencephalography (EEG), and concurrent TMS‐EEG to investigate longitudinal neurophysiological changes post‐stroke, and their relationship with behavioral changes. Subgroup analysis was performed based on the presence of paretic motor evoked potentials and motor function. Results: Functional connectivity was increased dramatically in low‐functioning individuals without elicitable motor evoked potentials (MEPs), which showed a positive effect on motor recovery. Functional connectivity was increased gradually in higher‐functioning individuals without elicitable MEP during stroke recovery and influence from the contralesional hemisphere played a key role in motor recovery. In individuals with elicitable MEPs, negative correlations between interhemispheric functional connectivity and motor function suggest that the influence from the contralesional hemisphere may be detrimental to motor recovery. Conclusion: Our results demonstrate prominent clinical implications for individualized stroke rehabilitation based on both functional integrity of the ipsilesional corticomotor pathway and motor function. [ABSTRACT FROM AUTHOR]

Macaques (genus Macaca) are the most widely distributed non‐human primates, and their evolutionary history, gene expression profiles, and genetic differences have been extensively studied. However, the DNA methylomes of macaque species are not available in public databases, which hampers understanding of epigenetic differences among macaque species. Epigenetic modifications can potentially affect development, physiology, behavior, and evolution. Here, we investigated the methylation patterns of the Tibetan macaque (M. thibetana; TM), Chinese rhesus macaque (M. mulatta lasiota; CR), and crab‐eating macaque (M. fascicularis; CE) through whole‐genome bisulfite sequencing from peripheral blood. We compared genome‐wide methylation site information for the three species. We identified 12,128 (CR vs. CE), 59,165 (CR vs. TM), and 39,751 (CE vs. TM) differentially methylated regions (DMRs) in the three macaques. Furthermore, we obtained the differentially expressed genes (DEGs) among the three macaque species. The differences between CR and CE were smaller at both the methylome and transcriptome levels than compared with TM (CR vs. TM and CE vs. TM). We also found a change in the density of single nucleotide mutations in DMRs relative to their flanking regions, indicating a potential mechanism through which genomic alterations may modulate methylation landscapes, thereby influencing the transcriptome. Functional enrichment analyses showed the DMR‐related genes were enriched in developmental processes and neurological functions, such as the growth hormone‐related pathway, insulin secretion pathway, thyroid hormone synthesis pathway, morphine addiction, and GABAergic synapses. These differences may be associated with variations in physiology and habitat among the macaques. Our study provides one of the first genome‐wide comparisons of genetic, gene expression, and epigenetic variations across different macaques. Our results should facilitate further research on comparative genomic and genetic differences in macaque species. [ABSTRACT FROM AUTHOR]

In view of the high failure rate of key parts and low reliability of the whole machine in the working process of the new forage crusher, the expert scoring method was used to predict the reliability of the forage crusher, and the IFM was used to allocate the reliability. The results showed that the predicted reliability value of forage grass crushing machine was 0.668, which could not meet the requirements of reliability standard of forage grass crushing machine in China. Reliability was redistributed based on the prediction results, and lower failure rate weights and higher reliability were assigned to rotor and power transmission parts. High failure rate weight and low reliability were assigned to the crusher body. After redistributing the reliability of each subsystem, the reliability of the whole machine was 0.902 59, which met the reliability requirements of forage kneading machine system. The study indicates that the research can provide a method of reference for reliability prediction and distribution of forage processing machinery. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting is long regarded as a green and feasible pathway to realize the scalable hydrogen production, while the overall hydrogen evolution reaction (HER) efficiency is largely dependent on the electrocatalytic ability of the cathode catalysts. Herein, the in situ growth of hydrazone‐linked covalent organic framework (COF‐42) nanocrystals with a unique nanoflower‐shaped morphology on 2D ultrathin Ti3C2Tx MXene nanosheets (COF/Ti3C2Tx) is achieved through a convenient and robust stereoassembly strategy. Strikingly, the marriage of COF‐42 and Ti3C2Tx nanosheets not only offers multiscale porous channels for the fast transportation of electrolyte and electrons, but also enables the full exposure and activation of numerous catalytically active centers. As a consequence, the optimized COF/Ti3C2Tx nanoarchitecture displays exceptional HER properties in terms of a very low onset potential of 19 mV, a small Tafel slope of 50 mV dec−1 as well as reliable long‐term durability, which are comparable to those of commercial Pt/C catalyst. Density functional theory calculations further disclose that the rational combination of COF‐42 with Ti3C2Tx provides more diversified active positions with appropriate ΔGH values, thus leading to a boosted hydrogen generation rate. [ABSTRACT FROM AUTHOR]