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Photocatalytic hydrogen peroxide production from water and oxygen offers a clean and sustainable alternative to the conventional energy-intensive anthraquinone oxidation method. Compared to powdered covalent triazine frameworks (CTFs), the film morphology of CTFs provides better connectivity in 2D, yielding several advantages: more efficient connections between active sites, reduced electron-hole pair recombination, increased resistance to superoxide radical induced corrosion, and decreased light scattering. Leveraging these benefits, it has incorporated dual active sites for both the oxygen reduction reaction (ORR) and the water oxidation reaction (WOR) into a CTF film system. This dual-active CTF film demonstrated an exceptional hydrogen peroxide production rate of 19 460 µmol h⻹ mâ»2 after 1 h and 17 830 µmol h⻹ mâ»2 after 5 h under visible light irradiation (≥420 nm) without the need for sacrificial agents.
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The solar-driven photocatalytic production of hydrogen peroxide (H2O2) from water and oxygen using semiconductor catalysts offers a promising approach for converting solar energy into storable chemical energy. However, the efficiency of photocatalytic H2O2 production is often restricted by the low photo-generated charge separation, slow surface reactions and inadequate stability. Here, we developed a mixed-linker strategy to build a donor-acceptor-acceptor (D-A-A) type covalent organic framework (COF) photocatalyst, FS-OHOMe-COF. The FS-OHOMe-COF structure features extended π-π conjugation that improves charge mobility, while the introduction of sulfone units not only as active sites facilitates surface reactions with water but also bolsters stability through increased interlayer forces. The resulting FS-OHOMe-COF has a low exciton binding energy, long excited-state lifetime and high photo-stability that leads to high performance for photocatalytic H2O2 production (up to 1.0â mM h-1) with an H2O2 output of 19â mM after 72â hours of irradiation. Furthermore, the catalyst demonstrates high stability, which sustained activity over 192â hours of photocatalytic experiment.
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Developing in situ/operando spectroscopic techniques with high sensitivity and reproducibility is of great importance for mechanistic investigations of surface-mediated electrochemical reactions. Herein, we report the fabrication of highly ordered rhombic gold nanocube superlattices (GNSs) as substrates for surface-enhanced infrared absorption spectroscopy (SEIRAS) with significantly enhanced SEIRA effect, which can be controlled by manipulating the randomness of GNSs. Finite difference time domain simulations reveal that the electromagnetic effect accounts for the significantly improved spectroscopic vibrations on the GNSs. In situ SEIRAS results show that the vibrations of CO on the Cu2O surfaces have been enhanced by 2.4 ± 0.5 and 18.0 ± 1.3 times using GNSs as substrates compared to those on traditional chemically deposited gold films in acidic and neutral electrolytes, respectively. Combined with isotopic labeling experiments, the reaction mechanisms for C-C coupling of CO electroreduction on Cu-based catalysts are revealed using the GNSs substrates.
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Direct CO2 electroreduction to valuable chemicals is critical for carbon neutrality, while its main products are limited to simple C1 /C2 compounds, and traditionally, the anodic O2 byproduct is not utilized. We herein report a tandem electrothermo-catalytic system that fully utilizes both cathodic (i.e., CO) and anodic (i.e., O2 ) products during overall CO2 electrolysis to produce valuable organic amides from arylboronic acids and amines in a separate chemical reactor, following the Pd(II)-catalyzed oxidative aminocarbonylation mechanism. Hexamethylenetetramine (HMT)-incorporated silver and nickel hydroxide carbonate electrocatalysts were prepared for efficient coproduction of CO and O2 with Faradaic efficiencies of 99.3 % and 100 %, respectively. Systematic experiments, operando attenuated total reflection surface-enhanced Fourier transform infrared spectroscopy characterizations and theoretical studies reveal that HMT promotes *CO2 hydrogenation/*CO desorption for accelerated CO2 -to-CO conversion, and O2 inhibits reductive deactivation of the Pd(II) catalyst for enhanced oxidative aminocarbonylation, collectively leading to efficient synthesis of 10 organic amides with high yields of above 81 %. This work demonstrates the effectiveness of a tandem electrothermo-catalytic strategy for economically attractive CO2 conversion and amide synthesis, representing a new avenue to explore the full potential of CO2 utilization.
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Tracking the trajectory of hydrogen intermediates during hydrogen electro-catalysis is beneficial for designing synergetic multi-component catalysts with division of chemical labor. Herein, we demonstrate a novel dynamic lattice hydrogen (LH) migration mechanism that leads to two orders of magnitude increase in the alkaline hydrogen oxidation reaction (HOR) activity on Pd@Pt over pure Pd, even ≈31.8â times mass activity enhancement than commercial Pt. Specifically, the polarization-driven electrochemical hydrogenation process from Pd@Pt to PdHx @Pt by incorporating LH allows more surface vacancy Pt sites to increase the surface H coverage. The inverse dehydrogenation process makes PdHx as an H reservoir, providing LH migrates to the surface of Pt and participates in the HOR. Meanwhile, the formation of PdHx induces electronic effect, lowering the energy barrier of rate-determining Volmer step, thus resulting in the HOR kinetics on Pd@Pt being proportional to the LH concentration in the in situ formed PdHx @Pt. Moreover, this dynamic catalysis mechanism would open up the catalysts scope for hydrogen electro-catalysis.
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Understanding the structure-stability relationship of catalysts is imperative for the development of high-performance electrocatalytic devices. Herein, we utilize operando attenuated total reflectance surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) to quantitatively monitor the evolution of Cu single-atom catalysts (SACs) during the electrochemical reduction of CO2 (CO2RR). Cu SACs are converted into 2-nm Cu nanoparticles through a reconstruction process during CO2RR. The evolution rate of Cu SACs is highly dependent on the substrates of the catalysts due to the coordination difference. Density functional theory calculations demonstrate that the stability of Cu SACs is highly dependent on their formation energy, which can be manipulated by controlling the affinity between Cu sites and substrates. This work highlights the use of operando ATR-SEIRAS to achieve mechanistic understanding of structure-stability relationship for long-term applications.
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Single-atom catalysts exhibit superior CO2 -to-CO catalytic activity, but poor kinetics of proton-coupled electron transfer (PCET) steps still limit the overall performance toward the industrial scale. Here, we constructed a Fe-P atom paired catalyst onto nitrogen doped graphitic layer (Fe1 /PNG) to accelerate PCET step. Fe1 /PNG delivers an industrial CO current of 1â A with FECO over 90 % at 2.5â V in a membrane-electrode assembly, overperforming the CO current of Fe1 /NG by more than 300 %. We also decrypted the synergistic effects of the P atom in the Fe-P atom pair using operando techniques and density functional theory, revealing that the P atom provides additional adsorption sites for accelerating water dissociation, boosting the hydrogenation of CO2 , and enhancing the activity of CO2 reduction. This atom-pair catalytic strategy can modulate multiple reactants and intermediates to break through the inherent limitations of single-atom catalysts.
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Zeolitic metal-organic frameworks (ZMOFs) have emerged as one of the most promsing catalysts for energy conversion, but they suffer from either weak bonding between metal-organic cubes (MOCs) that decrease their stability during catalysis processes or low activity due to inadequate active sites. In this work, through ligand-directing strategy, we successfully obtain an unprecedented bismuth-based ZMOF (Bi-ZMOF) featuring a ACO topological crystal structure with strong coordination bonding between the Bi-based cages. As a result, it enables efficient reduction of CO2 to formic acid (HCOOH) with Faradaic efficiency as high as 91 %. A combination of in situ surface-enhanced infrared absorption spectroscopy and density functional theory calculation reveals that the Bi-N coordination contributes to facilitating charge transfer from N to Bi atoms, which stabilize the intermediate to boost the reduction efficiency of CO2 to HCOOH. This finding highlights the importance of the coordination environment of metal active sites on electrocatalytic CO2 reduction. We believe that this work will offer a new clue to rationally design zeolitic MOFs for catalytic reaction.
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An efficient and energy saving photocatalytic coupling reaction of benzenesulfonyl hydrazide with bromoacetylene has been reported. A series of alkynylsulfones were obtained in up to 98% yield. In addition, changing the base from KHCO3 to KOAc can give the alkenylsulfone product. In addition, we tested the biological activity of some alkynylsulfone compounds and found that they exhibited excellent in vitro antioxidant activity by activating the Nrf2/ARE pathway, up to 8 fold.
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Atomically dispersed metal catalysts show potential advantages in N2 reduction reaction (NRR) due to their excellent activity and efficient metal utilization. Unfortunately, the reported catalysts usually exhibit unsatisfactory NRR activity due to their poor N2 adsorption and activation. Herein, we report a novel Sn atomically dispersed protuberance (ADP) by coordination with substrate C and O to induce positive charge accumulation on Sn site for improving its N2 adsorption, activation and NRR performance. The extended X-ray absorption fine structure (EXAFS) spectra confirmed the local coordination structure of the Sn ADPs. NRR activity was significantly promoted via Sn ADPs, exhibiting a remarkable NH3 yield (RNH3 ) of 28.3â µg h-1 mgcat -1 (7447â µg h-1 mgSn -1 ) at -0.3â V. Furthermore, the enhanced N2 Hx intermediates was verified by in situ experiments, yielding consistent results with DFT calculation. This work opens a new avenue to regulate the activity and selectivity of N2 fixation.
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Heteroepitaxial core-shell structure is conducive to combining the advantages of the epilayer and the substrate, creating a novel multifunctionality for catalysis application. Herein, we report a pseudomorphic-Pt atomic layer (PmPt) epitaxially growing on an IrPd-core matrix (PmPt@IrPd/C) as an efficient and stable catalyst for alkaline hydrogen oxidation reaction that exhibits â¼29.2 times more mass activity enhancement than that of benchmark Pt/C. The PmPt@IrPd/C catalyst also gives rise to â¼25.0 times more enhancement than Pt/C during a 50,000-cycle accelerated stability test. This robust stability originates from the resistance to carbon corrosion owing to the stronger H2O interaction instead of carbon oxide (COx) poison species, and the modulated hydroxyl (OH*) adsorption could inhibit the OH* species from shuffling the surface Pt atoms away from the substrate. Moreover, the anion-exchange membrane fuel cells assembled by PmPt@IrPd/C with an ultralow Pt loading of 0.009 mgPt cm-2 in the anode can deliver a power density of 1.27 W cm-2.
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Distributed electrochemical nitrogen reduction reaction (ENRR) powered by renewable energy for the on-site production of ammonia is an attractive alternative to the industrial Haber-Bosch process, which is responsible for roughly 2 % of global energy consumption. In this Review, we summarize recent progress in the ENRR catalyzed by transition metal nitrides (TMNs). The unique electronic structures of TMNs make them promising ENRR catalysts for active and selective ammonia production, which have been predicted theoretically and demonstrated experimentally. Reaction pathways and deactivation mechanisms of the ENRR on different TMNs are surveyed, and current understanding of structure-activity relations is discussed. To develop highly active, selective, and stable TMN catalysts for industrial-scale ENRR, membrane electrode assembly configuration is recommended in catalyst evaluation. Furthermore, we highlight the importance of developing mechanistic understanding on ENRR with different operando spectroscopic techniques.
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Previous studies have confirmed long noncoding RNA LEMD1-AS1 (LEMD1-AS1) as a functional factor in several tumors. The present work is aimed at exploring the prognostic and diagnostic values of LEMD1-AS1 in patients with epithelial ovarian cancer (EOC). We examined the expressions of LEMD1-AS1 in pan-cancer from TCGA microarray datasets and GTEx Project. The expressions of LEMD1-AS1 were detected by qRT-PCR in EOC specimens and normal ovarian specimens from 30 EOC patients. The χ 2 test was applied to compare the clinicopathological characteristics of different groups. ROC curves were established to determine the diagnostic values of LEMD1-AS1 in screening EOC tissues. The association of LEMD1-AS1 expression with clinical outcome was determined by the Kaplan-Meier methods and COX assays. A decreased expression of LEMD1-AS1 was observed in EOC tissues compared to matched normal specimens (p < 0.01). Low LEMD1-AS1 expression could be used to distinguish EOC from adjacent normal specimens. A clinical study revealed that patients with low LEMD1-AS1 expression have a shorter overall survival (p = 0.035) and progress-free interval (p = 0.041) than those with high LEMD1-AS1 expression. The Spearman correlation test revealed that LEMD1-AS1 expressions were negatively associated with the expressions of neutrophil and myeloid dendritic cell. Overall, our finding suggested that LEMD1-AS1 may have potential roles as a potential biomarker and/or a therapeutic target in EOC.
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Carcinoma Epitelial de Ovario , Proteínas de Neoplasias , Neoplasias Ováricas , ARN sin Sentido , Carcinoma Epitelial de Ovario/diagnóstico , Carcinoma Epitelial de Ovario/genética , Carcinoma Epitelial de Ovario/inmunología , Carcinoma Epitelial de Ovario/patología , Regulación hacia Abajo , Femenino , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/inmunología , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/genética , Neoplasias Ováricas/inmunología , Neoplasias Ováricas/patología , Pronóstico , ARN sin Sentido/genética , ARN sin Sentido/inmunología , ARN Largo no Codificante/genética , ARN Largo no Codificante/inmunologíaRESUMEN
BACKGROUND: Postpartum depression is one of the most common complications during the postpartum period. In recent years, internet-based psychological interventions have made significant progress and provided a new psychotherapy model. Internet-based cognitive behavioral therapy (ICBT) for postpartum depression has achieved good results. However, the effectiveness of ICBT for postpartum depression reported by different studies still remains inconsistent. Therefore, a meta-analysis was used to further evaluate the efficacy of ICBT for postpartum depression, aiming to provide evidence to support nonpharmacological intervention strategies in the clinic. METHODS: The databases of PubMed, Web of Science, Scopus, Cochrane Library, Embase, China Scientific Journal Database, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and Wanfang Data will be searched. The randomized controlled trials of ICBT will be included for postpartum depression published before February 2022. Two independent researchers will independently complete literature selection, risk of bias assessment and data extraction. The disagreements will be discussed with a third party for the final decision. Cochrane Risk of Bias Assessment Tool will be used for literature quality assessment. Data processing will be conducted by RevMan 5.4 software. RESULTS: The results of this meta-analysis will be submitted to a peer-reviewed journal for publication. CONCLUSIONS: For the question whether ICBT for postpartum depression is efficacy, this study can provide more comprehensive and strong evidence. ETHICS AND DISSEMINATION: The ethical approval was not required for this study. The systematic review will be published in a peer-reviewed journal, presented at conferences, and shared on social media platforms. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/EQJDH.
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Terapia Cognitivo-Conductual , Depresión Posparto/terapia , Internet , Terapia Cognitivo-Conductual/métodos , Femenino , Humanos , Metaanálisis como Asunto , Calidad de Vida , Proyectos de Investigación , Revisiones Sistemáticas como AsuntoRESUMEN
BACKGROUND: Surgical treatment for cervical cancer, as a stressor, largely leads to strong psychological reactions to stress like anxiety and depression. Whether mindfulness-based stress reduction (MBSR) can alleviate anxiety and depression in patients after cervical cancer surgery is controversial. Therefore, we aim to perform a meta-analysis involving randomized controlled trials analyzing the effect of MBSR on alleviating anxiety and depression in patients after cervical cancer surgery, thus providing evidence-based medical evidences for nonpharmacological interventions. METHODS: Randomized controlled trials analyzing the effect of MBSR on alleviating anxiety and depression in patients after cervical cancer surgery will be searched in online databases, including Cochrane Central Register of Controlled Trials Repositories, PubMed, Embase, Web of Science, Chinese Science Citation Database, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, Chinese Scientific Journal Database, and Wan Fang Data. After screening eligible studies, we will perform a meta-analysis on the effect of MBSR on alleviating anxiety and depression in patients after cervical cancer surgery. RESULTS: The results of this meta-analysis will be submitted to a peer-reviewed journal for publication. CONCLUSION: This study will provide reliable evidence-based evidences for the effects of MBSR on alleviating anxiety and depression in patients after cervical cancer surgery. ETHICS AND DISSEMINATION: Ethical approval was not required for this study. The systematic review will be published in a peer-reviewed journal, presented at conferences, and shared on social media platforms. OSF REGISTRATION NUMBER: DOI 10.17605/OSF.IO/EXUM3.
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Ansiedad , Depresión , Atención Plena , Neoplasias del Cuello Uterino , Ansiedad/etiología , Ansiedad/terapia , Depresión/etiología , Depresión/prevención & control , Femenino , Humanos , Metaanálisis como Asunto , Periodo Posoperatorio , Proyectos de Investigación , Revisiones Sistemáticas como Asunto , Neoplasias del Cuello Uterino/psicología , Neoplasias del Cuello Uterino/cirugíaRESUMEN
The aim of this retrospective study was to compare the safety and efficacy between laparoscopic myomectomy and traditional laparotomy for patients with uterine fibroids and determine their effect on the pregnancy rate after surgery. In total, 86 cases with uterine fibroids were selected among patients who were admitted in the Zhangqiu District Maternal and Child Health Care Hospital during the period of April, 2016 to April, 2017. Patients who underwent laparoscopic myomectomy were enrolled in group A (n=42), and those who underwent traditional laparotomy were placed in group B (n=44). The general linear data and the operative indicators were compared. The VAS scores, serum IFN-γ, IL-6, VEGF levels and clinical efficacy of the two groups were also compared one week after surgery. Postoperative pregnancy rates and complications in both groups were also compared. No significant differences were observed in general data between the two groups (P>0.05). The intra-operative blood loss in the group A was lower than that in group B (P<0.05), the average time of operation, hospital stays (days), and anal exhaust time in group A were shorter than those in group B (P<0.05). The pain degrees at 3, 6 and 18 h after surgery for patients in the group A were significantly lower than those of the group B (P<0.05). There was no significant difference IL-6 and VEGF levels in the serum between groups A and B before and after surgery (P>0.05); however, the level of IFN-γ expression, one week after surgery, in group B was significantly higher than that in group A (P<0.05). The pregnancy rate in the experimental group was higher than that in the control group (P<0.05), and the incidence rate of complications in group A was significantly lower than that in group B (P<0.05). Results presented in the present study suggested that compared to traditional laparotomy, laparoscopic myomectomy is a more advantageous method in terms of safety, efficacy and pregnancy rate after surgery.
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The data presented in this article are related to the research paper entitled "Cuticle ultrastructure of Baiera furcata from Northeast China and its implication in Taxonomy and Palaeoenvironment" (Guignard et al. 2019 [1]. The data correspond to a study of the ultrastructural fine cuticle details of fossil Baiera furcata (Ginkgoales) from the Lower Cretaceous Huolinhe Formation in Holingola of East Inner Mongolia, Northeast China. Two sets of data are provided here: 1/ thickness measurements of the layers of four types of cuticles, i.e. ordinary epidermal cells and stomatal apparatus, 2/ ten EDS element analysis of ordinary epidermal cell cuticle layers; the latter data also contain cuticle layers values of Sphenobaiera huangii from the Lower Jurassic Xiangxi Formation in Zigui of Hubei Province, Central China used for comparison in the research article; EDS cell remnant values of Baiera furcata are also included. Some of these data have been used efficiently for taxonomy and palaeoenvironment topics. As they are the first data for genera Baiera and Sphenobaiera of the Ginkgoales, they can serve in the future for considerations of taxonomical comparisons, palaeoreconstructions, palaeoenvironment and evolution.
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BACKGROUND: The aim of this study was to investigate the relationship of serum iron and ferritin concentrations in early pregnancy with gestational diabetes mellitus (GDM) complicated in pregnant metaphase through detecting the serum iron and ferritin concentrations in early pregnancy of normal pregnant women, so as to provide new ideas for the early detection and prevention of GDM. METHODS: Spontaneously pregnant women with single fetus receiving prenatal routine examination in our hospital from December 2014 to October 2016 were selected. They were in good health before with normal fasting blood-glucose in early pregnancy without anemia during pregnancy and any medication history. The serum iron and ferritin concentrations were measured at 12 gestational weeks, the fasting blood-glucose was detected at 12 weeks of pregnancy, and 75g oral glucose tolerance test was performed at 24-26 weeks. According to the results of oral glucose tolerance test, the pregnant women were divided into GDM group (N.=52) and normal control group (N.=310). The detection results of pregnant women in the two groups were statistically analyzed. RESULTS: The serum ferritin and iron levels at 12 gestational weeks in GDM group were higher than those in normal pregnancy group (P<0.05). The cut-off values of serum ferritin and iron at 12 gestational weeks in the prediction of GDM were 67.8 µg/L and 52.9 mmol/L. CONCLUSIONS: The high concentrations of serum iron and ferritin in early pregnancy have a certain correlation with the incidence of GDM, and the early detection of serum iron and ferritin levels can improve the detection rate of GDM in pregnant metaphase.
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Diabetes Gestacional/sangre , Ferritinas/sangre , Hierro/sangre , Primer Trimestre del Embarazo/sangre , Adulto , Biomarcadores , Glucemia , Diabetes Gestacional/diagnóstico , Femenino , Prueba de Tolerancia a la Glucosa , Humanos , EmbarazoRESUMEN
Chronic exposure to cortisol is associated with cardiovascular, metabolic, and psychiatric disorders. Although cortisol can be readily measured from peripheral sources such as blood, urine, or saliva, multiple samplings spanning several days to weeks are necessary to reliably assess chronic cortisol exposure levels (referred to as cortisol load). Although cortisol levels in hair have been proposed as a measure of cortisol load, measurement is cumbersome and many people are not candidates due to short hair length and use of hair dyes. To date, there are no blood biomarkers that capture cortisol load. To identify a blood biomarker capable of integrating one-month cortisol exposure levels, 75 healthy participants provided 30+ days of awakening and bedtime saliva cortisol and completed psychosocial measures of anxiety, depression, and stress. Mean daily awakening and bedtime cortisol levels were then compared to CpG methylation levels, gene expression, and genotypes of the stress response gene FKBP5 obtained from blood drawn on the last day of the study. We found a correlation between FKBP5 methylation levels and mean 30+day awakening and bedtime cortisol levels (|r|≥0.32, pâ¯≤â¯0.006). We also observed a sex-specific correlation between bedtime cortisol levels and FKBP5 mRNA expression in female participants (râ¯=â¯0.42, pâ¯=â¯0.005). Dividing the 30-day sampling period into four weekly bins showed that the correlations for both methylation and expression were not being driven by cortisol levels in the week preceding the blood draw. We also identified a female-specific association between FKBP5 mRNA expression and scores on the Beck Anxiety Inventory (râ¯=â¯0.37, pâ¯=â¯0.013) and Beck Depression Inventory-II (râ¯=â¯0.32, pâ¯=â¯0.033). Finally, DNA was genotyped at four SNPs, and variation in rs4713902 was shown to have an effect on FKBP5 expression under a codominant model (fâ¯=â¯3.41, pâ¯=â¯0.048) for females only. Our results suggest that blood FKBP5 DNA methylation and mRNA expression levels may be a useful marker for determining general or sex-specific 30-day cortisol load and justifies genome-wide approaches that can potentially identify additional cortisol markers with broader clinical utility.