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Inkjet-printed transparent electrodes: Design, characterization, and initial in vivo evaluation for brain stimulation
Electrical stimulation is a powerful tool for investigating and modulating brain activity, as well as for treating neurological disorders. However, understanding the precise effects of electrical stimulation on neural activity has been hindered by limitations in recording neuronal responses near the stimulating electrode, such as stimulation artifacts in electrophysiology or obstruction of the field of view in imaging. In this study, we introduce a novel stimulation device fabricated from conductive polymers that is transparent and therefore compatible with optical imaging techniques. The device is manufactured using a combination of microfabrication and inkjet printing techniques and is flexible, allowing better adherence to the brain’s natural curvature. We characterized the electrical and optical properties of the electrodes, focusing on the trade-off between the maximum current that can be delivered and optical transmittance. We found that a 1 mm diameter, 350 nm thick PEDOT:PSS electrode could be used to apply a maximum current of 130 μA while maintaining 84% transmittance (approximately 50% under 2-photon imaging conditions). We then evaluated the electrode performance in the brain of an anesthetized mouse by measuring the electric field with a nearby recording electrode and found values up to 30 V/m. Finally, we combined experimental data with a finite-element model of the in vivo experimental setup to estimate the distribution of the electric field underneath the electrode in the mouse brain. Our findings indicate that the device can generate an electric field as high as 300 V/m directly beneath the electrode, demonstrating its potential for studying and manipulating neural activity using a range of electrical stimulation techniques relevant to human applications. Overall, this work presents a promising approach for developing versatile new tools to apply and study electrical brain stimulation.
Author Correction: Dual-branch image projection network for geographic atrophy segmentation in retinal OCT images
Manipulation of interoceptive signaling biases decision making in rhesus macaques
Several influential theories have proposed that interoceptive signals, sent from the body to the brain, contribute to neural processes that coordinate complex behaviors. We altered the physiological state of the body using compounds that have minimal effect on the brain and evaluated their effect on decision making in rhesus monkeys. We used glycopyrrolate, a nonspecific muscarinic (parasympathetic) antagonist, and isoproterenol, a beta-1/2 (sympathetic) agonist, to create a sympathetic-dominated state in the periphery, that was indexed by increased heart rate. Rhesus monkeys were trained on two variants of an approach-avoidance conflict task. The tasks offered a choice between enduring mildly aversive stimuli in exchange for a steady flow of rewards, or canceling the aversive stimuli, forgoing the rewards. The latency to interrupt the aversive stimuli was used as a measure of monkeys’ tolerance for contact with a hot but not painful stimulus or airflow directed at their muzzle. Both drugs reduced tolerance for the aversive stimuli. To determine whether the drug-induced autonomic state reduced the subjective value of the reward, we tested the effects of glycopyrrolate on a food preference task. Food preference was unaltered, suggesting that the sympathetic dominated state in the periphery selectively reduces tolerance for aversive stimuli without altering reward-seeking behaviors. As the drugs used are expected to have little or no direct effect on the brain, the observed biases in decision making are likely induced by interoceptive afferents that signal to the brain the physiological state of the body.
Lysine-arginine imbalance overcomes therapeutic tolerance governed by the transcription factor E3-lysosome axis in glioblastoma
Association of overweight/obesity and digestive system cancers: A meta-analysis and trial sequential analysis of prospective cohort studies
Background Previous researches have reported correlations between overweight/obesity and common digestive system cancers (DSCs), including gastric, liver, esophageal, colorectal, and pancreatic cancers. However, the inconsistency in defining overweight/obesity and the risk of recall bias from case-control and retrospective cohort studies may influence existing results. Therefore, we aimed to validate the relationship between overweight/obesity and common DSCs by combining prospective cohort studies based on the World Health Organization (WHO) criteria for defining overweight/obesity. Methods A comprehensive literature search was conducted across PubMed, Embase, Web of Science, and Cochrane databases, covering all publications up to February 7, 2024. The inclusion criteria focused on prospective cohort studies that examined the link between overweight/obesity and risks of DSCs. R software 4.1.3 and STATA 12 were utilised to calculate the relative risk (RR), with 95% confidence interval (CI) and prediction interval (PI). TSA v0.9.5.10 Beta software was used for trial sequential analysis (TSA). Results The meta-analysis encompassed 39 articles. The overall analysis showed that compared with normal weight, overweight/obesity increased the risks of liver cancer (overweight: RR [95% CI] = 1.237 [1.112-1.377]; 95% PI: 0.888-1.725; obesity: RR [95% CI] = 1.642 [1.466-1.839]; 95% PI: 1.143-2.358) and colorectal cancer (overweight: RR [95% CI] = 1.124 [1.056-1.197]; 95% PI: 0.931-1.357; obesity: RR [95% CI] = 1.366 [1.242-1.503]; 95% PI: 0.959-1.945) in the total population. Subgroup analysis revealed that overweight (RR [95% CI] = 1.237 [1.165-1.314]; 95% PI: 1.154-1.327) and obesity (RR [95% CI] = 1.306 [1.152-1.480]; 95% PI: 1.108-1.539) were associated with an increased risk of pancreatic cancer only in women, and overweight also increased the gastric cancer risk of women (RR [95% CI] = 1.041 [1.013-1.070], 95% PI: 0.806-1.230). No significant association of overweight/obesity and esophageal cancer was observed in both male and female. Conclusion Our study suggested that overweight/obesity elevated the risks of liver and colorectal cancer in both men and women. No significant association was found between overweight/obesity and the risk of developing esophageal cancer. Clinicians are advised to consider weight control as an effective measure for preventing pancreatic, liver, and colorectal cancers.
Polarisation reconfigurable anisotropic dielectric resonator antenna
Abstract A novel polarization reconfigurable anisotropic dielectric resonator antenna (ADRA) is presented utilizing a new modulation scheme to exploit the degree of freedom in the polarization domain. The ADRA comprises periodic assembly dielectric resonators with two different dielectrics constant, equal in size, a vertically positioned metal strip, one varactor diode, and six PIN diode switches. The modulation scheme utilizes the tilt angle and axial ratio (AR) of a wireless signal to convey additional information, enabling the realization of different working modes ranging from circular polarization (CP) to nearly linear polarization (LP). The proposed modulation scheme yields significantly better bit error rate (BER) performance and higher spectral efficiency in bits/s/Hz/antenna. Additionally, the paper presents an antenna design capable of generating an arbitrary polarization state, highlighting the system benefits of polarization modulation. Post-fabrication, the proposed approach is validated by comparing simulated and measured results. The proposed antenna provides a total efficiency higher than 93% in the desired frequency bands and consistent gain at approximately 7.64 dBi and 7.09 dBi at 3.8 GHz, with the impedance matching bandwidth ranging from 3.53 to 3.90 GHz and 3.56 to 3.91 GHz fully overlapping across all polarization states for the simulated and measured results, respectively. Experimental results affirm the robust performance of the proposed ADRA.
Modulation of host gene expression by the zinc finger antiviral protein
The zinc finger antiviral protein (ZAP) depletes nonself RNAs through recognition of their elevated CpG dinucleotide content. CpG dinucleotides are sparse in most endogenous mammalian mRNAs, but a subset might potentially be modulated by ZAP. While CpG frequency alone is insufficient to predict ZAP-regulation, we developed an algorithm using experimentally determined compositional features to predict which endogenous mRNAs may be ZAP-regulated. Using ZAP-knockout mice, we demonstrate that levels of many host mRNAs that are algorithmically predicted ZAP targets are indeed increased when ZAP is absent. ZAP is interferon-inducible, and we also identify genes that are downregulated by ZAP during an innate immune response. Many ZAP-regulated gene products are extracellular matrix or of nucleosome components, whose ZAP-mediated control is conserved in human cells. Overall, we provide a tool for the prediction of ZAP target genes and reveal host mRNAs that are ZAP-regulated.
Design and implementation of aerobic and ambient CO2-reduction as an entry-point for enhanced carbon fixation
Abstract The direct reduction of CO2 into one-carbon molecules is key to highly efficient biological CO2-fixation. However, this strategy is currently restricted to anaerobic organisms and low redox potentials. In this study, we introduce the CORE cycle, a synthetic metabolic pathway that converts CO2 to formate at aerobic conditions and ambient CO2 levels, using only NADPH as a reductant. Combining theoretical pathway design and analysis, enzyme bioprospecting and high-throughput screening, modular assembly and adaptive laboratory evolution, we realize the CORE cycle in vivo and demonstrate that the cycle supports growth of E. coli by supplementing C1-metabolism and serine biosynthesis from CO2. We further analyze the theoretical potential of the CORE cycle as a new entry-point for carbon in photorespiration and autotrophy. Overall, our work expands the solution space for biological carbon reduction, offering a promising approach to enhance CO2 fixation processes such as photosynthesis, and opening avenues for synthetic autotrophy.
Correction: Protective effects of Euphorbia heterophylla against testicular degeneration in streptozotocin-induced diabetic rats in relation to phytochemical profile
Cable vibration and girder displacement measurement via morphology recognition and feature matching methods in bridge structure
Bayesian inference by visuomotor neurons in the prefrontal cortex
Perceptual judgments of the environment emerge from the concerted activity of neural populations in decision-making areas downstream of the sensory cortex. When the sensory input is ambiguous, perceptual judgments can be biased by prior expectations shaped by environmental regularities. These effects are examples of Bayesian inference, a reasoning method in which prior knowledge is leveraged to optimize uncertain decisions. However, it is not known how decision-making circuits combine sensory signals and prior expectations to form a perceptual decision. Here, we study neural population activity in the prefrontal cortex of macaque monkeys trained to report perceptual judgments of ambiguous visual stimuli under two different stimulus distributions. We isolate the component of the neural population response that represents the formation of the perceptual decision (the decision variable, DV), and find that its dynamical evolution reflects the integration of sensory signals and prior expectations. Prior expectations impact the DV’s trajectory both before and during stimulus presentation such that DV trajectories with a smaller dynamic range result in more biased and less sensitive perceptual decisions. We show that these results resemble a specific variant of Bayesian inference known as approximate hierarchical inference. Our findings expand our understanding of the mechanisms by which prefrontal circuits can execute Bayesian inference.
Structural insights into the dual Ca2+-sensor-mediated activation of the PPEF phosphatase family
Comparative evaluation of Allplex HPV28 and Anyplex II HPV28 assays for high-risk HPV genotyping in cervical samples
Background/Objectives Human papillomavirus (HPV) genotyping is essential for cervical cancer screening and prevention. The AllplexTM HPV28 real-time PCR kit, using different chemistry and results analysis compared with its predecessor, the AnyplexTM II HPV28 kit, has recently been launched. This study aims to compare the AllplexTM HPV28 and AnyplexTM II HPV28 assays in detecting and genotyping the 13 high-risk (HR)-HPV types. Study design Between 2022 and 2023, 459 cervical samples from women undergoing cervical cancer screening were selected. These samples were analysed by liquid-based cytology and tested by both kits concurrently. Results AllplexTM HPV28 Ct values correlated well with AnyplexTM II HPV28 signal intensity scores. No significant differences between assays were observed in overall and genotype-specific HR-HPV prevalence determined in all samples and according to cytological results. In addition, no significant differences were identified between assays in the detection of single and multiple HR-HPV infections. Most of the discordant results corresponded to samples showing weak HR-HPV signals and multiple HR-HPV types. Conclusions Our results demonstrate that the AllplexTM HPV28 kit can be used for HPV genotyping, with results overall similar to those obtained with the AnyplexTM II HPV28 kit and the addition of Ct values for patient follow-up. The clinical implications of the potentially reduced sensitivity of the AllplexTM HPV28 kit in detecting HPV31 (p = 0.07) and HPV39 (p = 0.08) warrant further investigation in subsequent studies.
An adaptive search mechanism with convolutional learning networks for online social media text summarization and classification model
Cholesterol-dependent enzyme activity of human TSPO1
The amino acid sequence of the tryptophan-rich sensory proteins (TSPO) is substantially conserved throughout all kingdoms of life. Human mitochondrial TSPO1 ( Hs TSPO1) binds to porphyrins and steroids, although its interactions with these molecules remains unknown. Hs TSPO1 is associated with numerous physiological and pathological disorders, but the underlying molecular mechanisms are unknown. Here, we disclose the finding of human mitochondrial TSPO as a cholesterol-dependent protoporphyrin IX oxygenase. The results of our biochemical characterization are consistent with structural data and evolutionary analysis. The dependence of Hs TSPO1 activity on cholesterol may be the result of the coevolution of this membrane protein with the membrane system. Our study provides a molecular foundation for comprehending the various roles played by mitochondrial TSPO in normal physiological and pathological situations.
Sulfur defect engineering controls Li2S crystal orientation towards dendrite-free lithium metal batteries
Abstract Controlling nucleation and growth of Li is crucial to avoid dendrite formation for practical applications of lithium metal batteries. Li2S has been exemplified to promote Li transport, but its crystal orientation significantly influences the Li deposition behaviors. Here, we investigate the interactions between Li and various surface structures of Li2S, and reveal that the Li2S(111) plane exhibits the highest Li affinity and the lowest diffusion barrier, leading to dense Li deposition. Using sulfur defect engineering for Li2S crystal orientation control, we construct three-dimensional vertically oriented Li2S(111)@Cu nanorod arrays as a Li metal electrode substrate and identify a substrate-dependent Li nucleation process and a facet-dependent growth mode. Furthermore, we demonstrate the versatility of the Li2S(111)@Cu substrate when paired with two positive electrodes: achieving an initial discharge capacity of 138.8 mAh g–1 with 88% capacity retention after 400 cycles at 83.5 mA g–1 with LiFePO4, and an initial discharge capacity of 181 mAh g–1 with 80% capacity retention after 160 cycles at 60 mA g–1 with commercial LiNi0.8Co0.1Mn0.1O2 positive electrode (4 mAh cm–2).
Intermittent hypoxic stimulation promotes efficient expression of Hypoxia-inducible factor-1α and exerts a chondroprotective effect in an animal osteoarthritis model
Hypoxia-inducible factor-1α plays an important role in the homeostasis of articular cartilage in hypoxic environments. Therefore, modulation of hypoxia-inducible factor-1α by regulating the oxygen environment could be a useful treatment for osteoarthritis. This study aimed to assess the chondroprotective effects of intermittent hypoxia on cultured chondrocytes and an animal model of osteoarthritis. In vitro, human chondrocytes were exposed to 2 h of hypoxic stimulation three times at 1-h intervals, and protein and gene expression of hypoxia-inducible factor-1α, ACAN, and cell viability was measured over time. In vivo, 8-week-old male Wistar rats were injected with monosodium iodoacetate to induce osteoarthritis and then reared in 12% hypoxia for 24 h, followed by 24 h in steady oxygen, repeated alternately for a total of 28 days. A histological analysis was performed on days 8 and 28. In the intermittent hypoxia group, each protein expression increased with each repeated hypoxic stimulation to human chondrocytes; finally, the protein level was significantly higher with intermittent hypoxia than with continuous hypoxic stimulation, cell viability was increased, and gene expression was not significantly increased. In the osteoarthritis animal model, for 8 days, there were stronger hypoxia-inducible factor-1α staining and no significant differences in articular cartilage destruction. Furthermore, for 28 days, there was significantly less articular cartilage destruction in the rat osteoarthritis model with intermittent hypoxia than with steady oxygen rearing. Intermittent hypoxia increased cartilage metabolism by increasing hypoxia-inducible factor-1α proteins in articular chondrocytes, which may be effective in preventing articular cartilage degeneration in a rat osteoarthritis model.
Immobilization of silver nanoparticles and silver iodide within bamboo fabrics for wastewater treatment
Abstract Pathogenic microorganisms and dyes are the main sources of water pollution. These pollutants are extremely hazardous and may harm aquatic life and human health. As a result, removing these pollutants is critical in assessing contamination risks and mitigating potential health hazards. To effectively remove pathogenic microorganisms and dyes from wastewater, an efficient multi-functional material was designed based on AgI, Ag NPs, and Ag NPs@AgI immobilized on bamboo fabrics as a support substrate. The water disinfection aptitude of the modified bamboo fabrics was evaluated against different microorganisms. The results showed that the Ag NPs@AgI@bamboo showed excellent antibacterial activity against S. aureus (88%) and E. coli (90%) as well as perfect antifungal activity against C. albicans (82%). Methylene blue (MB) was used as a pollutant model to test the catalytic and photocatalytic activity of modified bamboo fabrics. The results show that Ag NPs@AgI@bamboo was highly efficient in removing the MB dye via reduction (90%) after 60 min or photodegradation (93%) after 6 h of UV light irradiation. The pseudo-first-order kinetic study shows that Ag NPs@AgI@bamboo possessed outstanding catalytic reduction and photocatalytic degradation activities toward MB.