Proton-pumping photoreceptor controls expression of ABC transporter by regulating transcription factor through light.

Light is a significant factor for living organisms with photosystems, like microbial rhodopsin-a retinal protein that functions as an ion pump, channel, and sensory transduction. Gloeobacter violaceus PCC7421, has a proton-pumping rhodopsin gene, the Gloeobacter rhodopsin (GR). The helix-turn-helix family of transcriptional regulators has various motifs, and they regulate gene expression in the presence of various metal ions. Here, we report that active proton outward pumping rhodopsin interacted with the helix-turn-helix transcription regulator and regulated gene expression. This interaction is confirmed using ITC analysis (KD of 8 µM) and determined the charged residues required. During in vitro experiments using fluorescent and luciferase reporter systems, ATP-binding cassette (ABC) transporters and the self-regulation of G. violaceus transcriptional regulator (GvTcR) are regulated by light, and gene regulation is observed in G. violaceus using the real-time polymerase chain reaction. These results expand our understanding of the natural potential and limitations of microbial rhodopsin function.

Cobalt-Copper-Embedded Nitrogen-Doped Carbon Nanostructures Derived from Zeolite Imidazolate Frameworks as Electrocatalysts for the Oxygen Reduction Reaction.

In recent years, researchers have focused on developing zeolite imidazolate frameworks (ZIFs) as an alternative to Pt electrocatalysts for various applications, including water splitting, lithium-air batteries, zinc-air batteries, and fuel cells. In this study, we synthesized CoCu-ZIF to be used as a precursor in the development of cathode catalysts for the oxygen reduction reaction (ORR) in fuel cells. Hydrazine played a crucial role in maintaining uniformity in the development and particle size of the ZIF-67 structures. Moreover, it facilitated the rapid formation of the ZIF-67 structures at higher temperatures. A unique pseudorhombic dodecahedral morphology was obtained at a Co/Cu molar ratio of 7:3. Among all the synthesized N-doped carbon nanostructures embedded with Co and Cu nanoparticles, CoCu@NC-750, pyrolyzed at 750 °C, showed superior ORR catalytic performance. This catalyst exhibited a notably higher half-wave potential of 0.816 V and demonstrated a clear 4-electron transfer mechanism. The overpotential of CoCu@NC-750 shifted by only 11 mV over 10,000 cyclic voltammetry cycles, whereas a 55 mV shift was observed for Pt/C. CoCu@NC-750 exhibited a ∼0.8% decrease in current density during a 12-h ORR, in contrast to the 8.3% decline shown by Pt/C. This superior catalytic activity and stability can be attributed to factors such as higher oxygen adsorption induced by the N-doped carbon layer due to the localized changes in electron density and the enhanced stability of the bimetallic core. Our findings suggest that CoCu@NC-750 is a promising alternative to Pt/C in fuel cell cathodes.

Unveiling the critical role of K+ for xanthorhodopsin expression in E. coli.

Xanthorhodopsin (XR), a retinal-binding 7-transmembrane protein isolated from the eubacterium Salinibacter ruber, utilizes two chromophores (retinal and salinixanthin (SAL)) as an outward proton pump and energy-donating carotenoid. However, research on XR has been impeded owing to limitations in achieving heterogeneous expression of stable forms and high production levels of both wild-type and mutants. We successfully expressed wild-type and mutant XRs in Escherichia coli in the presence of K+. Achieving XR expression requires significant K+ and a low inducer concentration. In particular, we highlight the significance of Ser-159 in helix E located near Gly-156 (a carotenoid-binding position) as a critical site for XR expression. Our findings indicate that replacing Ser-159 with a smaller amino acid, alanine, can enhance XR expression in a manner comparable to K+, implying that Ser-159 poses a steric hindrance for pigment formation in XR. In the presence of K+, the proton pumping and photocycle of the wild-type and mutants were characterized and compared; the wild-type result suggests similar properties to the first reported XR isolation from the S. ruber membrane fraction. We propose that the K+ gradient across the cell membrane of S. ruber serves to uphold the membrane potential of the organism and plays a role in the expression of proteins, such as XR, as demonstrated in our study. Our findings deepen the understanding of adaptive protein expression, particularly in halophilic organisms. We highlight salt selection as a promising strategy for improving protein yield and functionality.

Home-based up-dosing of wheat oral immunotherapy: Real-world effectiveness and predictive factor analysis.

BACKGROUND: Wheat allergy is one of the most prevalent allergens in Korea, decreasing quality of life and causing nutritional repercussions. OBJECTIVE: We aimed to investigate the efficacy and safety of the home-based wheat oral immunotherapy (OIT) using wheat noodles in children with a wheat allergy. METHODS: We conducted a retrospective study involving 72 children aged 3 to 17 years diagnosed with a wheat allergy. Patients received wheat OIT using wheat noodles (n = 50) and were compared with a historical control group (n = 22). Baseline characteristics, adverse events, and immunological changes were assessed. Predictors of successful desensitization were identified using logistic regression analysis. RESULTS: Among 50 patients completing the up-dosing phase, 82.0% achieved desensitization to 2,400 mg of wheat protein, compared to 4.5% in the control group (p < 0.001). During the up-dosing period, the median number of adverse reactions per person was 2, and anaphylaxis occurred in 30.0% (15/50). However, there were no life-threatening adverse events. In multivariable analysis, the presence of asthma (adjusted odds ratio [aOR], 8.88; 95% confidence interval [CI], 1.10-71.97; p = 0.041) and a higher ratio of specific IgE (sIgE) to ω-5-gliadin and total IgE (aOR 19.09, 95%CI 1.21-300.80, p = 0.036) were significantly associated with treatment outcomes of wheat OIT. CONCLUSION: Our study showed the safety and efficacy of home-based wheat OIT using boiled noodles in Korean children with wheat allergies. Careful consideration is warranted for patients with elevated baseline sIgE to ω-5-gliadin to total IgE ratio and a history of asthma.

Distal forelimb radiographic bone morphology in Thoroughbred foals during the first 10 months post-partum. Part 1: Carpus.

BACKGROUND: The risk of carpal injury in racehorses may be related to the morphology, yet whether carpal morphologies are set from birth or change through growth remains unclear. OBJECTIVE: To quantify carpal bone changes through growth. METHOD: Twenty privately owned Thoroughbred foals born between January 2022 and May 2023 were radiographed bimonthly from birth to 10 months of age. Imprint training was used to take radiographs safely without chemical restraints. Fifteen individual and 11 relative angular carpal parameters were measured using ImageJ on dorsopalmar radiographs of the carpus at zero degrees of vertical and horizontal rotation. Associations with age (growth), sex and the differences between left and right limbs were analysed separately using a linear mixed effects model. RESULTS: Six individual carpal parameters changed with age (radial carpal joint [RCJ], Prx.dor. radial carpal [Cr], Prx.Cu, Dis.dor. third carpal [C3], Dis.pal.C3 and Dis.pal. intermediate carpal), and one was influenced by side, that is higher in the left carpus (Dis.pal.Cr). Seven relative parameters changed with age, and one relative parameter was influenced by side, that is higher in the left (Ra.met-RCJ). The proximo-dorsal bone surface angle of Cr and disto-dorsal bone surface angle of C3 became flatter over time, which may be associated with the re-direction of the load towards the sagittal carpal plane. Sex did not influence any of the carpal parameters, nor did the combined effect of age, side of the limb and sex. CONCLUSION: Specific individual and relative angular carpal parameters changed significantly over time and some differed between the left and right limb, whereas other parameters did not change. The steeper carpal bone angles achieved proximally with the parameters that did change may improve stability by redirecting the load more medially through the carpus and the proximal and distal bones.

Rhizobacterial syntrophy between a helper and a beneficiary promotes tomato plant health.

Microbial interactions impact the functioning of microbial communities. However, microbial interactions within host-associated communities remain poorly understood. Here, we report that the beneficiary rhizobacterium Niallia sp. RD1 requires the helper Pseudomonas putida H3 for bacterial growth and beneficial interactions with the plant host. In the absence of the helper H3 strain, the Niallia sp. RD1 strain exhibited weak respiration and elongated cell morphology without forming bacterial colonies. A transposon mutant of H3 in a gene encoding succinate-semialdehyde dehydrogenase displayed much attenuated support of RD1 colony formation. Through the subsequent addition of succinate to the media, we found that succinate serves as a public good that supports RD1 growth. Comparative genome analysis highlighted that RD1 lacked the gene for sufficient succinate, suggesting its evolution as a beneficiary of succinate biosynthesis. The syntrophic interaction between RD1 and H3 efficiently protected tomato plants from bacterial wilt and promoted tomato growth. The addition of succinate to the medium restored complex II-dependent respiration in RD1 and facilitated the cultivation of various bacterial isolates from the rhizosphere. Taken together, we delineate energy auxotrophic beneficiaries ubiquitous in the microbial community, and these beneficiaries could benefit host plants with the aid of helpers in the rhizosphere.

Potential Effects of Low-Level Toluene Exposure on the Nervous System of Mothers and Infants.

In day-to-day living, individuals are exposed to various environmentally hazardous substances that have been associated with diverse diseases. Exposure to air pollutants can occur during breathing, posing a considerable risk to those with environmental health vulnerabilities. Among vulnerable individuals, maternal exposure can negatively impact the mother and child in utero. The developing fetus is particularly vulnerable to environmentally hazardous substances, with potentially greater implications. Among air pollutants, toluene is neurotoxic, and its effects have been widely explored. However, the impact of low-level toluene exposure in daily life remains unclear. Herein, we evaluated 194 mothers and infants from the Growing children's health and Evaluation of Environment (GREEN) cohort to determine the possible effects of early-life toluene exposure on the nervous system. Using Omics experiments, the effects of toluene were confirmed based on epigenetic changes and altered mRNA expression. Various epigenetic changes were identified, with upregulated expression potentially contributing to diseases such as glioblastoma and Alzheimer's, and downregulated expression being associated with structural neuronal abnormalities. These findings were detected in both maternal and infant groups, suggesting that maternal exposure to environmental hazardous substances can negatively impact the fetus. Our findings will facilitate the establishment of environmental health policies, including the management of environmentally hazardous substances for vulnerable groups.

Effectiveness of Exercise Programs for Alleviation of Upper Body Pain in Patients with Spinal Cord Injury: A Systematic Review.

(1) Background: Upper body pain, particularly in the limbs and shoulders, is a common symptom among patients with spinal cord injury (SCI) and wheelchair users. Despite the focus on resistance muscle training as a suitable intervention for SCI individuals, findings across different populations and conditions have been inconsistent. (2) Methods: We conducted a systematic review to elucidate the correlations among exercise interventions, muscle strength enhancement, and pain reduction. A comprehensive literature search was performed using the keywords "spinal cord injury," "pain," "exercise," "disability," "paraplegia," and "tetraplegia" across the DBpia, EMBASE, PubMed, and Science Direct databases. (3) Results: From 191 identified articles, 13 studies (1 from Korea and 12 from other countries) were selected for analysis. The results indicate that exercise interventions are effective in reducing pain in patients with SCI, with a particular emphasis on alleviating shoulder pain. (4) Conclusion: Exercise is essential for pain reduction in patients with SCI, especially those experiencing shoulder pain. However, there is a notable lack of experimental research focusing primarily on pain. The development of appropriate measurement instruments is crucial for the prevention and relief of pain in this patient population.

Prevalence of Severe Atopic Dermatitis and Comorbid Chronic Systemic Diseases Is Increasing in Korean Children and Adolescents.

Severe atopic dermatitis (AD) is not a localized cutaneous disease, but a systemic disease that often accompanies comorbidities. In this nationwide population-based study, we aimed to analyze the prevalence of severe AD and chronic systemic diseases in Koreans aged ≤ 20 years between 2011 and 2019 using the data from the Korean Health Insurance Review and Assessment Service. Total AD and severe AD were defined according to the International Classification of Diseases-10 code L20. In children aged 6-20 years, the prevalence of severe AD significantly increased from 0.02% in 2011 to 0.04% in 2019 (P for trend < 0.001), with the ratio of severe AD to total AD increasing from 0.76% in 2011 to 1.10% in 2019 (P for trend < 0.001). The prevalence rates of severe AD significantly increased between 2011 and 2019 in children aged 6-12 years (P for trend < 0.05) and 13-18 years (P for trend < 0.001). Severe AD was more frequently found in males than in females each year (all P < 0.001, from 2011 to 2019). During the period from 2011 to 2019, the prevalence rate of chronic systemic diseases was higher in subjects with severe AD than in those without AD (P < 0.001) or with mild-to-moderate AD (P < 0.001). In conclusion, our results suggest that the prevalence of severe AD is increasing in Korean children and adolescents and is higher in males and older age groups. Moreover, severe AD is associated with chronic systemic diseases. Therefore, more attention should be paid to managing severe AD.

Advanced fructo-oligosaccharides improve itching and aberrant epidermal lipid composition in children with atopic dermatitis.

Introduction: The effects of fructo-oligosaccharides (FOS) on atopic dermatitis (AD) have not been determined. Methods: In a randomized, double-blind, placebo-controlled trial, children with AD aged 24 months to 17 years received either advanced FOS containing 4.25 g of 1-kestose or a placebo (maltose) for 12 weeks. Results: The SCORAD and itching scores were reduced in patients treated with both FOS (all p < 0.01) and maltose (p < 0.05 and p < 0.01). Sleep disturbance was improved only in the FOS group (p < 0.01). The FOS group revealed a decreased proportion of linoleic acid (18:2) esterified omega-hydroxy-ceramides (EOS-CERs) with amide-linked shorter chain fatty acids (C28 and C30, all p < 0.05), along with an increased proportion of EOS-CERs with longer chain fatty acids (C32, p < 0.01). Discussion: FOS may be beneficial in alleviating itching and sleep disturbance, as well as improving skin barrier function in children with AD.

Heliorhodopsin-mediated light-modulation of ABC transporter.

Heliorhodopsins (HeRs) have been hypothesized to have widespread functions. Recently, the functions for few HeRs have been revealed; however, the hypothetical functions remain largely unknown. Herein, we investigate light-modulation of heterodimeric multidrug resistance ATP-binding cassette transporters (OmrDE) mediated by Omithinimicrobium cerasi HeR. In this study, we classifiy genes flanking the HeR-encoding genes and identify highly conservative residues for protein-protein interactions. Our results reveal that the interaction between OcHeR and OmrDE shows positive cooperatively sequential binding through thermodynamic parameters. Moreover, light-induced OcHeR upregulates OmrDE drug transportation. Hence, the binding may be crucial to drug resistance in O. cerasi as it survives in a drug-containing habitat. Overall, we unveil a function of HeR as regulatory rhodopsin for multidrug resistance. Our findings suggest potential applications in optogenetic technology.

LC-MS-MS method for mitragynine and 7-hydroxymitragynine in hair and its application in authentic hair samples of suspected kratom abusers.

Kratom is a natural psychoactive product known primarily in Southeast Asia, including Thailand, Malaysia, etc. It is also known as krathom, kakuam, ithang, thom (Thailand), biak-biak, ketum (Malaysia) and mambog (Philippines) and is sometimes used as an opium substitute. It is stimulant at doses of 1-5 g, analgesic at doses of 5-15 g and euphoric and sedative at doses of >15 g. Mitragynine is the most abundant indole compound in kratom (Mitragyna speciosa) and is metabolized in humans to 7-hydroxymitragynine, the more active metabolite. Adverse effects include seizures, nausea, vomiting, diarrhea, tachycardia, restlessness, tremors, hallucinations and death. There are few studies on the analytical method for the detection of mitragynine and 7-hydroxymitragynine in hair. Therefore, this study proposes a liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the analysis of kratom in hair. Hair samples were first weighed to ∼10 mg and washed with methanol. Then the washed hair samples were cut into pieces and incubated in methanol with stirring and heating (16 h/38℃). Extracts were then analyzed by LC-MS-MS. This method was validated by determining the limit of detection (LOD), limit of quantification, linearity, intra- and inter-day accuracy and precision, recovery and matrix effects. The intra- and inter-day precision (CV%) and accuracy (bias%) were within ±20%, which was considered acceptable. Using this newly developed LC-MS-MS method, the simultaneous detection of mitragynine and 7-hydroxymitragynine in six authentic hair samples was achieved to provide the direct evidence of kratom use in the past. Mitragynine concentrations ranged from 16.0 to 2,067 pg/mg (mean 905.3 pg/mg), and 7-hydroxymitragynine concentrations ranged from 0.34 to 15 pg/mg (mean 7.4 pg/mg) in six authentic hair samples from kratom abusers. This may be due to the higher sensitivity of the LOD in this study, with values of 0.05 pg/mg for mitragynine and 0.2 pg/mg for 7-hydroxymitragynine in hair.

Risk of Ischemic Stroke in Relation to Helicobacter pylori Infection and Eradication Status: A Large-Scale Prospective Observational Cohort Study.

Background/Aims: : A few studies have suggested the association between Helicobacter pylori (HP) infection and ischemic stroke. However, the impact of HP eradication on stroke risk has not been well evaluated. This study aimed to assess the influence of HP eradication on the incidence of ischemic stroke, considering the potential effect of sex. Methods: : This prospective observational cohort study was conducted at Seoul National University Bundang Hospital, from May 2003 to February 2023, and involved gastroscopy-based HP testing. Propensity score (PS) matching was employed to ensure balanced groups by matching patients in the HP eradicated group (n=2,803) in a 3:1 ratio with patients in the HP non-eradicated group (n=960). Cox proportional hazard regression analysis was used to evaluate the risk of ischemic stroke. Results: : Among 6,664 patients, multivariate analysis after PS matching indicated that HP eradication did not significantly alter the risk of ischemic stroke (hazard ratio, 0.531; 95% confidence interval, 0.221 to 1.270; p=0.157). Sex-specific subgroup analyses, both univariate and multivariate, did not yield statistically significant differences. However, Kaplan-Meier analysis revealed a potential trend: the females in the HP eradicated group exhibited a lower incidence of ischemic stroke than those in the HP non-eradicated group, although this did not reach statistical significance (p=0.057). Conclusions: : This finding suggests that HP eradication might not impact the risk of ischemic stroke. However, there was a trend showing that females potentially had a lower risk of ischemic stroke following HP eradication, though further investigation is required to establish definitive evidence.

Designing a Se-intercalated MOF/MXene-derived nanoarchitecture for advancing the performance and durability of lithium-selenium batteries.

Lithium-selenium batteries have emerged as a promising alternative to lithium-sulfur batteries due to their high electrical conductivity and comparable volume capacity. However, challenges such as the shuttle effect of polyselenides and high-volume fluctuations hinder their practical implementation. To address these issues, we propose synthesizing Fe-CNT/TiO2 catalyst through high-temperature sintering of an amalgamated nanoarchitecture of carbon nanotubes decorated metal-organic framework (MOF) and MXene, optimized for efficient selenium hosting, leveraging the distinctive physicochemical properties. The catalytic features inherent in the porous Se@Fe-CNT/TiO2 nanoarchitecture were instrumental in promoting efficient ion and electron transport, and lithium-polyselenide kinetics, while its inherent porosity could play a crucial role in inhibiting electrode stress during cycling. This nanoarchitecture exhibits remarkable battery performance, retaining 99.7% of theoretical capacity after 425 cycles at 0.5 C rate and demonstrating 95.8% capacity retention after 2000 cycles at 1 C rate, with ∼100% Coulombic efficiency. Additionally, the Se@Fe-CNT/TiO2 electrode exhibited an impressive recovery of 297.5 mAh/g (97.9%) capacity after undergoing 450 cycles at a charging rate of 10 C and a discharging rate of 1 C. This synergistic integration of MOF- and MXene-derived materials unveils new possibilities for high-performance and durable LSeBs, thus advancing electrochemical energy storage systems.

Left Atrium Volume Measured with Multislice Computed Tomography as a Prognostic Predictor for Atrial Fibrillation Catheter Ablation Outcomes.

Background: Current guidelines consider atrial fibrillation (AF) type as the prognostic factor for a recommendation of catheter ablation. We aimed to determine whether LA and LA appendage (LAA) volumes measured using multislice computed tomography (MSCT) were related to long-term outcomes in AF following radiofrequency catheter ablation (RFCA). Methods: We evaluated 152 consecutive patients with drug-refractory AF (median age, 55.8 ± 9.6 years), including 110 male patients, who underwent RFCA in a single center. All patients underwent MSCT imaging for anatomical assessment. The endpoint of this study was documented AF recurrence after RFCA. Results: The overall procedure success rate was 77.6% (n = 118) during a mean follow-up period of 12.6 months. The LA volume was significantly larger for those who experienced AF recurrence after RFCA than for the patients without recurrent AF after the procedure (153.8 ± 29.9 mL vs. 139.2 ± 34.1 mL, p = 0.025). However, LAA volumes were nearly equivalent between the patients with and without AF recurrence after RFCA (16.2 ± 6.3 mL and 14.7 ± 6.5 mL, respectively; p = 0.235). LA volume ≥ 153.2 mL was the optimal cutoff value for estimating AF recurrence after RFCA, with 94% sensitivity and 66% specificity. LA volume remained an independent predictor of both AF recurrence and permanent AF. Conclusions: LA volume as assessed by MSCT might be helpful for identifying patients likely to achieve successful AF ablation. LA volume ≥ 153.2 mL, but not LAA volume, showed good accuracy in predicting AF recurrence after RFCA.

Anti-Inflammatory Effects of Artemisia argyi H. Fermented by Lactobacillus plantarum in the LPS-Induced RAW 264.7 Cells and DSS-Induced Colitis Model.

Ulcerative colitis is a chronic inflammatory disease caused by abnormal immune responses in the intestinal mucosa and gut microorganisms. Unlike other mugworts, Artemisia argyi H. (A. argyi H.) enhances antioxidant, anti-inflammatory, and anticancer effects, but the improvement effects against gut inflammation have not yet been reported. Therefore, this study aimed to confirm the alleviation of the inflammatory state in the gut by A. argyi H. fermented with Lactobacillus plantarum (FAA), using lipopolysaccharide (LPS)-induced RAW 264.7 cells and dextran sulfate sodium (DSS)-induced colitis models. In vitro, FAA (10, 50, 100, and 200 µg/mL) was pretreated into RAW 264.7 cells, followed with LPS (100 ng/mL), which induced the cell damage. Meanwhile, in vivo, FAA (100, 200 mg/kg/day) was orally administered into 6-week-old C57BL/6N mice for 3 weeks. During the last week of FAA administration, 2.5% DSS was used to induce colitis. The results showed that FAA reduced the production of nitric oxide (p < 0.0001), tumor necrosis factor (TNF)-α, interleukin (IL)-6 (p < 0.0001), and IL-1ß (p < 0.0001) in the LPS-induced RAW 264.7 cells. Moreover, in the DSS-induced colitis model, FAA alleviated clinical symptoms (p < 0.001), inhibited the inflammatory state by reducing the production of TNF-α (p < 0.0001) and interferon-γ in intestinal immune cells (p < 0.0001), and strengthened the intestinal barrier by increasing the number of goblet cells (p < 0.0001). Furthermore, the anti-inflammatory effects were confirmed by the alleviation of histological damage (p < 0.001) and down-regulation of the expression of inflammatory proteins (TLR4, p < 0.0001; MyD88, p < 0.0001; Cox-2, p < 0.0001). These results suggest the potential of FAA as a dietary ingredient for preventing inflammation in the gut.

The Microbiome Matters: Its Impact on Cancer Development and Therapeutic Responses.

In the evolving landscape of cancer research, the human microbiome emerges as a pivotal determinant reshaping our understanding of tumorigenesis and therapeutic responses. Advanced sequencing technologies have uncovered a vibrant microbial community not confined to the gut but thriving within tumor tissues. Comprising bacteria, viruses, and fungi, this diverse microbiota displays distinct signatures across various cancers, with most research primarily focusing on bacteria. The correlations between specific microbial taxa within different cancer types underscore their pivotal roles in driving tumorigenesis and influencing therapeutic responses, particularly in chemotherapy and immunotherapy. This review amalgamates recent discoveries, emphasizing the translocation of the oral microbiome to the gut as a potential marker for microbiome dysbiosis across diverse cancer types and delves into potential mechanisms contributing to cancer promotion. Furthermore, it highlights the adverse effects of the microbiome on cancer development while exploring its potential in fortifying strategies for cancer prevention and treatment.

Transport Dynamics of Water Molecules Confined between Lipid Membranes.

Water molecules confined between biological membranes exhibit a distinctive non-Gaussian displacement distribution, far different from that of bulk water. Here, we introduce a new transport equation for water molecules in the intermembrane space, quantitatively explaining molecular dynamics simulation results. We find that the unique transport dynamics of water molecules stems from the lateral diffusion coefficient fluctuation caused by their longitudinal motion in the direction perpendicular to the membranes. We also identify an interfacial region where water possesses distinct physical properties, which is unaffected by changes in the intermembrane separation.

Behavior can be decoded across the cortex when individual differences are considered.

Group-level analyses have typically associated behavioral signatures with a constrained set of brain areas. Here we show that two behavioral metrics - reaction time (RT) and confidence - can be decoded across the cortex when each individual is considered separately. Subjects (N=50) completed a perceptual decision-making task with confidence. We built models decoding trial-level RT and confidence separately for each subject using the activation patterns in one brain area at a time after splitting the entire cortex into 200 regions of interest (ROIs). At the group level, we replicated previous results by showing that both RT and confidence could be decoded from a small number of ROIs (12.0% and 3.5%, respectively). Critically, at the level of the individual, both RT and confidence could be decoded from most brain regions even after Bonferroni correction (90.0% and 72.5%, respectively). Surprisingly, we observed that many brain regions exhibited opposite brain-behavior relationships across individuals, such that, for example, higher activations predicted fast RTs in some subjects but slow RTs in others. These results were further replicated in a second dataset. Lastly, we developed a simple test to determine the robustness of decoding performance, which showed that several hundred trials per subject are required for robust decoding. These results show that behavioral signatures can be decoded from a much broader range of cortical areas than previously recognized and suggest the need to study the brain-behavior relationship at both the group and the individual level.