Library-Assisted Evolution in Eukaryotic Cells Yield Adenine Base Editors with Enhanced Editing Specificity.

The current-generation adenine base editor (ABE) ABE8e, which has evolved from the prokaryotic evolution system, exhibits high efficiency in mediating A-to-G conversion and is presumed to be promising for gene therapy. However, its much wider editing window and substantially higher off-target editing activity restricted its applications in precise base editing for therapeutic use. This study uses a library-assisted protein evolution approach using eukaryotic cells to generate ABE variants with improved specificity and reduced off-target editing while maintaining high activity in human cells. The study generated an expanded set of ABEs with efficient editing activities and chose four evolved variants that offered either similar or modestly higher efficiency within a narrower editing window of protospacer position ≈4-7 compared to that of ABE8e in human cells, which would enable minimized bystander editing. Moreover, these variants resulted in reduced off-target editing events when delivered as plasmid or mRNA into human cells. Finally, these variants can install both disease-suppressing mutations and disease-correcting mutations efficiently with minimal undesired bystander editing making them promising approaches for specific therapeutic edits. In summary, the work establishes a mutant-library-assisted protein evolution method in eukaryotic cells and generates alternative ABE variants as efficient tools for precise human genome editing.

Longitudinal Mapping of Personal Biotic and Abiotic Exposomes and Transcriptome in Underwater Confined Space Using Wearable Passive Samplers.

Silicone-based passive samplers, commonly paired with gas chromatography-mass spectrometry (GC-MS) analysis, are increasingly utilized for personal exposure assessments. However, its compatibility with the biotic exposome remains underexplored. In this study, we introduce the wearable silicone-based AirPie passive sampler, coupled with nontargeted liquid chromatography with high-resolution tandem mass spectrometry (LC-HRMS/MS), GC-HRMS, and metagenomic shotgun sequencing methods, offering a comprehensive view of personalized airborne biotic and abiotic exposomes. We applied the AirPie samplers to 19 participants in a unique deep underwater confined environment, annotating 4,390 chemical and 2,955 microbial exposures, integrated with corresponding transcriptomic data. We observed significant shifts in environmental exposure and gene expression upon entering this unique environment. We noted increased exposure to pollutants, such as benzenoids, polycyclic aromatic hydrocarbons (PAHs), opportunistic pathogens, and associated antibiotic-resistance genes (ARGs). Transcriptomic analyses revealed the activation of neurodegenerative disease-related pathways, mostly related to chemical exposure, and the repression of immune-related pathways, linked to both biological and chemical exposures. In summary, we provided a comprehensive, longitudinal exposome map of the unique environment and underscored the intricate linkages between external exposures and human health. We believe that the AirPie sampler and associated analytical methods will have broad applications in exposome and precision medicine.

Refined Sound Therapy in Combination with Cognitive Behavioural Therapy to Treat Tinnitus: A Randomized Controlled Trial.

Background: Post-auricular injection of lidocaine and methylprednisolone sodium succinate is a commonly used treatment for outpatient patients with tinnitus, but it is invasive, painful and has uncertain efficacy. We need to try to replace it with more non-invasive and effective treatments. The 2014 guidelines of the American Academy of Otolaryngology-Head and Neck Surgery recommend the use of cognitive behavioral therapy (CBT) to treat tinnitus. Some clinical doctors have also attempted sound therapy for tinnitus. It is unclear whether sound therapy combined with CBT y is more effective than local injection of lidocaine and methylprednisolone sodium succinate in treating tinnitus. Objective: To evaluate the efficacy and influencing factors of refined sound therapy combined with CBT in the treatment of tinnitus and compare it with post-auricular injection of lidocaine and methylprednisolone sodium succinate. Methods: We recruited 100 patients with tinnitus; ultimately, 81 patients completed the experiment and underwent follow-up. Patients were randomly assigned to either the treatment group (refined sound therapy combined with CBT) or the control group (post-auricular injections of lidocaine and methylprednisolone sodium succinate). Data was collected from 49 patients in the treatment group and 32 patients in the control group. Pre- and post-treatment data were collected using the Self-Rating Depression Scale (SDS), Hamilton Anxiety Rating Scale (HAM-A), Visual Analogue Score (VAS), Tinnitus loudness and Tinnitus Handicap Inventory (THI) score. Comparisons between groups were performed using the chi-square test, Fisher's exact test, or Wilcoxon rank-sum test. All tests were two-sided and considered statistically significant with P < .05. Results: The THI, SDS and HAM-A scores in the treatment group decreased significantly. In the control group, there was a significant reduction in THI scores, but not in SDS and HAM-A scores. In addition, tinnitus loudness and VAS scores were significantly decreased in the 2 groups. There was a significant difference in the reduction of THI, SDS, HAM-A and VAS scores between the 2 groups; the treatment group showed a greater reduction. However, there was no significant difference in the reduction of tinnitus loudness. There was no statistical difference in the reduction of THI scores, SDS scores, VAS scores and tinnitus loudness in different frequency groups, but there was a statistical difference in the reduction of HAM-A scores. There was no statistical difference in the reduction of THI scores, SDS scores, HAM-A scores, VAS scores and tinnitus loudness between patients with and without hearing loss. Conclusions: (1) This new combination is more effective than post-auricular injection of lidocaine and methylprednisolone sodium succinate in treating tinnitus and improving psychological symptoms. The latter had no effect on improving psychological indicators. (2) With this combination, patients with different tinnitus frequencies experienced different improvements in anxiety. (3) Low-frequency tinnitus seems have been more likely to cause sound adaptation. (4) The improvement in tinnitus and anxiety was the same regardless of whether or not there was hearing loss.

Facile Synthesis of 2D SiOx -3D Si Hybrid Anode Materials by Ca Modification Effect for Enhanced Lithium Storage Performance.

Al-Si dealloying method is widely used to prepare Si anode for alleviating the issues caused by a drastic volume change of Si-based anode. However, this method suffers from the problems of low Si powder yield (<20 wt.% Si) and complicated cooling equipment due to the hindrance of large-size primary Si particles. Here, a new modification strategy to convert primary Si to 2D SiOx nanosheets by introducing a Ca modifier into Al-Si alloy melt is presented. The thermodynamics calculation shows that the primary Si is preferentially converted to CaAl2 Si2 intermetallic compound in Al-Si-Ca alloy system. After the dealloying process, the CaAl2 Si2 is further converted to 2D SiOx nanosheets, and eutectic Si is converted to 3D Si, thus obtaining the 2D SiOx -3D Si hybrid Si-based materials (HSiBM). Benefiting from the modification effect, the HSiBM anode shows a significantly improved electrochemical performance, which delivers a capacity retention of over 90% after 100 cycles and keeps 98.94% capacity after the rate test. This work exhibits an innovative approach to produce stable Si-based anode through Al-Si dealloying method with a high Si yield and without complicated rapid cooling techniques, which has a certain significance for the scalable production of Si-based anodes.

Promising Subjective and Objective Benefits of Modified Mindfulness-Based Stress Reduction Training for Chinese Adults with Chronic Pain: A Pilot Randomized Control Study.

INTRODUCTION: Mindfulness-based stress reduction (MBSR) has demonstrated its effectiveness in reducing pain-related stress in adults with chronic pain. However, the implementation of MBSR needs modifications across cultures. This pilot study reports the findings of a randomized controlled trial that investigated the effects of a culturally adaptive MBSR program on self-report and neuroimaging outcomes for chronic pain adults in China. METHODS: Sixty-seven participants were randomly assigned to the treatment group (n = 40) or the treatment-as-usual group (n = 27) group at a ratio of 1.5:1. Participants completed self-report measures of pain severity, pain interference, depression, perceived stress, pain catastrophizing, mindfulness, and resilience at baseline assessment (T1), post-treatment (T2), and 3-month follow-up (T3) assessments. Functional magnetic resonance imaging (fMRI) scanning was also performed at T1 and T3 assessments. RESULTS: For the intention-to-treat sample, the results of the mixed-effect model indicated that Group × Time interaction was significant for pain catastrophizing only (F (2, 130) = 3.51, p = 0.033). Compared with the control group, those in the MBSR group reported greater reductions in pain catastrophizing at T2 (d = - 0.60), though this effect was not maintained at T3 (d = - 0.05). Additionally, the results of completer analyses found significant Group × Time interactions for pain interference (F (2, 88) = 4.40, p = 0.015) and perceived stress (F (2, 88) = 3.13, p = 0.048), but not for other measures. Finally, both groups exhibited decreased regional homogeneity (ReHo) in the frontal lobe, while increased ReHo in the cerebellum anterior lobe was unique to the MBSR group. CONCLUSIONS: The present findings suggest that the minor modified MBSR program improves certain pain-related outcomes for Chinese adults with chronic pain. Future studies with larger samples of Chinese chronic pain patients are needed to detect the small-to-moderate benefit of MBSR on fMRI and/or other objective methods.

Psychological outcomes of the systematic interventions based on the stress-induced situation, affective, bodily, and cognitive reactions framework for patients with lung cancer: A randomized clinical trial.

BACKGROUND: Psychological distress is a multi-factorial unpleasant experience of a psychological, social, spiritual, and/or physical nature that may interfere with one's ability to cope effectively with cancer, physical symptoms and treatment. Psychological distress is common and affects the prognosis of cancer patients. Lung cancer accounted for 11.4 % of all new cancer cases and 18 % of all cancer mortality for 36 cancers in 185 countries. The prevalence of distress among Chinese lung cancer patients ranged from 10.1 % to 61.29 %. However, the existing intervention studies on the psychological distress in lung cancer patients are limited and intervention results may be different. OBJECTIVES: To explore the psychological outcomes of a nurse-led systematic intervention program based on the stress-induced situation, affective, bodily, and cognitive reactions framework for patients with lung cancer undergoing operation at anxiety and depression. DESIGN: A randomized clinical trial. SETTING: Thoracic surgery ward in a tertiary hospital in China. PARTICIPANTS: Lung cancer patients undergoing surgery. METHODS: This is a 12-month longitudinal randomized controlled study in a tertiary hospital in China. A total of 240 lung cancer patients were randomly divided into either the control group or the intervention group. The nurse-led systematic intervention contents include psychological education, intervention measures based on the stress-induced situation, affective, bodily, and cognitive reactions framework, issuance of daily lifestyle cards, and regular follow-ups. The Hospital Anxiety and Depression Scale, Functional Assessment of Chronic Illness Therapy-Fatigue Scale, and Satisfaction with Life Scale were used for the baseline assessment within 48 h upon admission. The same assessment was performed respectively at 1, 3, 6 and 12 months after the intervention started. The effects of the systematic interventions on depression, anxiety, fatigue, and life satisfaction were tested by a linear mixed effects model. RESULTS: Overall time-by-group interaction effects were significantly different with regard to anxiety, depression, and fatigue after controlling for the covariates, while a significant time-by-group interaction effect was not found for life satisfaction. Changes for anxiety and depression scores at 6 and 12 months after initiation of the intervention were significantly greater in the intervention group compared with those in the control group (t = 3.046, p = 0.002, t = 3.190, p = 0.001; t = 3.735, p = 0.000, t = 2.979, p = 0.002), whereas scores for fatigue were significantly higher in the intervention group at 6 and 12 months (t = -3.096, p = 0.002, t = -2.784, p = 0.005). CONCLUSION: The systematic intervention program based on the stress-induced situation, affective, bodily, and cognitive reactions framework may effectively relieve anxiety, depression, and fatigue in lung cancer patients undergoing surgery. REGISTRATION: This study was registered on December 22, 2019 with the registration number ChiCTR1900028487, and the date of first recruitment was Jan 5, 2020.

Effects of False Feedback on Pain Tolerability Among Young Healthy Adults: Predictive Roles of Intentional Effort Investment and Perceived Pain Intensity.

Purpose: Expectations and modification gained through critical learning influence pain perception. We tested how pain tolerability was influenced by the effects of orally delivered false feedback and participant status immediately prior to performing tasks. Patients and Methods: A total of 125 healthy college students (69 females and 56 males) were randomly assigned to 3 groups (positive, negative, and control) to participate in two formal cold pressor tests (CPTs). Participants completed the same series of task-related questionnaires (perceived importance, intended effort, current affect, and self-efficacy) before each CPT. False performance feedback was delivered after completion of the baseline level CPT. After completion of each CPT, both pain intensity and pain tolerability (duration in ice water) were recorded. Results: The results of linear mixed models revealed significant condition × time interactions on pain tolerability and task self-efficacy after controlling for individual variance as a random effect. Participants who received negative feedback exhibited increased pain tolerability without decreasing their self-efficacy, whereas participants who received positive feedback showed increased self-efficacy with no change in pain tolerability. A longer pain tolerance duration was also predicted by a more intentional investment of effort and a lower intensity of experienced pain as well as the effect of false feedback. Conclusion: The research highlights the effect of powerful situational influences on laboratory-induced pain tolerance.

Therapeutic adenine base editing of human hematopoietic stem cells.

In ß-thalassemia, either γ-globin induction to form fetal hemoglobin (α2γ2) or ß-globin repair to restore adult hemoglobin (α2ß2) could be therapeutic. ABE8e, a recently evolved adenine base editor variant, can achieve efficient adenine conversion, yet its application in patient-derived hematopoietic stem cells needs further exploration. Here, we purified ABE8e for ribonucleoprotein electroporation of ß-thalassemia patient CD34+ hematopoietic stem and progenitor cells to introduce nucleotide substitutions that upregulate γ-globin expression in the BCL11A enhancer or in the HBG promoter. We observed highly efficient on-target adenine base edits at these two regulatory regions, resulting in robust γ-globin induction. Moreover, we developed ABE8e-SpRY, a near-PAMless ABE variant, and successfully applied ABE8e-SpRY RNP to directly correct HbE and IVS II-654 mutations in patient-derived CD34+ HSPCs. Finally, durable therapeutic editing was produced in self-renewing repopulating human HSCs as assayed in primary and secondary recipients. Together, these results support the potential of ABE-mediated base editing in HSCs to treat inherited monogenic blood disorders.

CRISPR-Cas9-mediated gene editing of the BCL11A enhancer for pediatric ß0/ß0 transfusion-dependent ß-thalassemia.

Gene editing to disrupt the GATA1-binding site at the +58 BCL11A erythroid enhancer could induce γ-globin expression, which is a promising therapeutic strategy to alleviate ß-hemoglobinopathy caused by HBB gene mutation. In the present study, we report the preliminary results of an ongoing phase 1/2 trial (NCT04211480) evaluating safety and efficacy of gene editing therapy in children with blood transfusion-dependent ß-thalassemia (TDT). We transplanted BCL11A enhancer-edited, autologous, hematopoietic stem and progenitor cells into two children, one carrying the ß0/ß0 genotype, classified as the most severe type of TDT. Primary endpoints included engraftment, overall survival and incidence of adverse events (AEs). Both patients were clinically well with multilineage engraftment, and all AEs to date were considered unrelated to gene editing and resolved after treatment. Secondary endpoints included achieving transfusion independence, editing rate in bone marrow cells and change in hemoglobin (Hb) concentration. Both patients achieved transfusion independence for >18 months after treatment, and their Hb increased from 8.2 and 10.8 g dl-1 at screening to 15.0 and 14.0 g dl-1 at the last visit, respectively, with 85.46% and 89.48% editing persistence in bone marrow cells. Exploratory analysis of single-cell transcriptome and indel patterns in edited peripheral blood mononuclear cells showed no notable side effects of the therapy.

Physical activity and sleep differences between osteoarthritis, rheumatoid arthritis and non-arthritic people in China: objective versus self report comparisons.

BACKGROUND: Objectively measured differences in physical activity (PA) and sleep have been documented among people with osteoarthritis (OA) and rheumatoid arthritis (RA) compared to non-arthritic controls. However, it is not clear whether OA and RA subgroups also differ on these indexes or the extent to which distinct arthritis subgroups versus controls can be accurately identified on the basis of objective PA and sleep indexes compared to self-report responses on questionnaires. This study addressed these gaps. METHODS: This case-control study comprised Chinese adults with OA (N = 40) or RA (N = 40) diagnoses based on physician assessments as well as a control group of adults without chronic pain (N = 40). All participants wore a Sensewear Armband (SWA) for consecutive 7 days and completed the International Physical Activity Questionnaire Short Form-Chinese as well as Pittsburgh Sleep Diary to obtain objective and subjective PA and sleep data, respectively. RESULTS: There were no differences between the three groups on any self-report indexes of PA or sleep. Conversely, OA and RA subgroups displayed significantly lower PA levels and more sleep problems than controls did on a majority of SWA indexes, though arthritis subgroups were not differentiated from one another on these measures. Logistic regression analyses indicated four non-multicollinear SWA indexes (i.e., steps, active energy expenditure, vigorous activity, time awake after sleep onset) correctly identified the subgroup membership of 75.0-82.5% of participants with RA or OA while classification accuracy results were attenuated for controls. CONCLUSIONS: Where possible, objective measures should be used to assess PA and sleep of adults with OA and RA while particular self-report PA questionnaires should be used sparingly.

Trait Mindfulness Moderates the Association Between Stressor Exposure and Perceived Stress in Law Enforcement Officers.

OBJECTIVES: To test the magnitude of the relationship between self-reported stressor exposure and perceived stress in police officers using a novel measure of daily work events, and whether dispositional mindfulness and resilience moderate this relationship. METHODS: A total of 114 law enforcement officers from a mid-sized Midwestern US city completed daily logs of job stressors and associated perceived stress, as well as additional self-report measures of perceived stress, trait mindfulness and resilience, and demographics and work information. Principal component analysis (PCA) was used to cluster job stressors into a smaller number of components in a data-driven manner. Linear mixed-effects models were used to test the relationship between stressor exposure and perceived stress for each component, and the moderation of this relationship by trait mindfulness and resilience. RESULTS: The PCA categorized stressor exposure into three components: (1) acute or traumatic line-of-duty stressors, (2) routine daily stressors, and (3) interpersonal stressors. Results of mixed models showed robust positive relationships between self-reported stressor exposure and corresponding perceived stress across all 3 components. Dispositional mindfulness (but not resilience) moderated the association between stressor exposure and perceived stress for routine stressors, such that individuals with higher dispositional mindfulness showed a relatively attenuated relationship between exposure to routine daily stressors and resulting perceived stress. CONCLUSIONS: Police officers high in dispositional mindfulness may experience daily routine stressors as less stressful, which can reduce the accumulation of general stress in the long term and which could help buffer against negative health outcomes associated with perceived stress. TRIAL REGISTRATION: Clinicaltrials.gov/ct2/show/NCT03488875. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12671-021-01707-4.

Simulation stress model of the undersea environment activates the central nervous, neuroendocrine and immune systems and anxiety in rats.

The present study was designed to assess the stress responses to a simulation model of the undersea environment that is similar to some undersea working conditions such as submarine rescue, underwater salvage and underwater construction. Restraint, hyperbaric air and immersion were chosen to produce the simulation stress model in rats for four hours. Rats were randomized into five groups: control group, restraint (R) group, hyperbaric air (H) group, restraint plus hyperbaric air (RH) group, and restraint plus hyperbaric air plus immersion (RHI) group. The results showed that the responses to the simulation stress model of the undersea environment induced by R, H, RH and RHI involved the upregulated norepinephrine (NE), dopamine (DA) and 5-hydroxytryptamine (5-HT) of the central nervous system (CNS), upregulated adrenocorticotropic hormone (ACTH), corticosterone (CORT) and blood glucose of the neuroendocrine system, upregulated interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) of the immune system, and increased anxiety in rats. Compared with hyperbaric air, restraint tended to activate stronger stress responses. Conclusively, this work established a simulation stress model of the undersea environment induced by restraint, hyperbaric air and immersion. It further provided experimental data of such a model that showed significant activation of the CNS, neuroendocrine and immune systems and anxiety in rats. In this experiment we provided an experimental basis for undersea work such as working aboard a submarine.

Toward Current Matching in Tandem Dye-Sensitized Solar Cells.

The tandem pn-type dye-sensitized solar cells (pn-DSCs) have received much attention in the field of photovoltaic technologies because of their great potential to overcome the Shockley-Queisser efficiency limitation that applies to single junction photovoltaic devices. However, factors governing the short-circuit current densities (Jsc) of pn-DSC remain unclear. It is typically believed that Jsc of the pn-DSC is limited to the highest one that the two independent photoelectrodes can achieve. In this paper, however, we found that the available Jsc of pn-DSC is always determined by the larger Jsc that the photoanode can achieve but not by the smaller one in the photocathode. Such experimental findings were verified by a simplified series circuit model, which shows that a breakdown will occur on the photocathode when the photocurrent goes considerably beyond its threshold voltage, thus leading to an abrupt increase in Jsc of the circuit. The simulation results also suggest that a higher photoconversion efficiency of the pn-DSCs can be only achieved when an almost equivalent photocurrent is achieved for the two photoelectrodes.

Factor structure, correlates, and incremental validity of the Pain Appraisal Inventory-Short Form.

We assessed the factor structure, correlates, and incremental validity of the Pain Appraisal Inventory in Chinese adult chronic pain samples. In an initial exploratory factor analysis sample (N = 301), the original two-component (threat, challenge) 16-item Pain Appraisal Inventory and a 10-item short form (Pain Appraisal Inventory-Short Form) were supported. Within a confirmatory factor analysis sample (N = 285), uniformly acceptable fits were observed only for the Pain Appraisal Inventory-Short Form. Furthermore, Pain Appraisal Inventory-Short Form threat and challenge subscales had significant correlations with conceptually related measures and added to prediction models for pain-related coping and adjustment, independent of other pain belief scales. Together, results indicated that the Pain Appraisal Inventory-Short Form has utility in Chinese chronic pain samples.

Hierarchical Porous Metallic V2O3@C for Advanced Aqueous Zinc-Ion Batteries.

Aqueous Zn-ion batteries (ZIBs) are a potential electrochemical energy storage device because of their highly intrinsic safety, low cost, and large capacity. However, it is still in the primary stage because of the limited selection of cathode materials with high rate and long-life cycling stability. In addition, the energy storage mechanisms of ZIBs have not been well established. In this work, we report the synthesis of porous V2O3@C materials with high conductivity and further illustrate its application as the intercalation cathode for aqueous zinc-ion batteries. The unique channel and appropriate pore size distribution of corundum-type V2O3 are beneficial to the rapid zinc ion intercalation and removal, leading to a high rate capability. Also, the carbon framework structure achieves a high cyclic stability. The porous V2O3@C cathode delivers high capacities of 350 mA h g-1 at 100 mA g-1, an excellent rate capability (250 mA h g-1 at 2 A g-1), and an impressive long-life cycling stability with 90% capacity retention over 4000 cycles at 5 A g-1. The storage mechanism of zinc ions in the Zn/V2O3 system was studied by various analytical methods and first-principles calculation.

Causal effects of challenge and threat appraisals on pain self-efficacy, pain coping, and tolerance for laboratory pain: An experimental path analysis study.

BACKGROUND: Primary appraisals of pain as a potential threat influence pain perception and coping but comparatively less is known about related effects of challenge appraisals or causal effects of primary appraisals on secondary appraisals of perceived pain coping capacities (e.g., pain self-efficacy). METHODS: To address these gaps, young Chinese women (N = 147) and men (N = 88) were randomly assigned to one of three appraisal conditions prior to engaging in a cold pressor test (CPT): (1) a higher threat appraisal condition featuring task orienting information describing symptoms and consequences of frostbite, (2) a lower threat appraisal condition featuring orienting information about safety of the CPT, or (3) a challenge appraisal condition featuring orienting information describing benefits of persistence despite discomfort for future life satisfaction. RESULTS: Compared to peers in the higher threat condition, challenge condition cohorts experienced smaller decreases in task-related self-efficacy, more cognitive coping, and less catastrophizing as well as more overall pain tolerance. A path analysis indicated that self-efficacy changes, cognitive coping and catastrophizing fully mediated links of subjective challenge and threat appraisals with pain tolerance. CONCLUSIONS: Initial appraisals about the nature of pain influence, not only pain tolerance and coping, but also perceived coping capacities. PERSPECTIVE: Through examining particular theory-based pain appraisal and coping processes, this experiment is the first to identify both perceived coping capacities (pain self-efficacy) and coping responses as factors that explain why appraisals of pain as a challenge or threat have differential effects on pain tolerance.

Human substance P receptor binding mode of the antagonist drug aprepitant by NMR and crystallography.

Neurokinin 1 receptor (NK1R) has key regulating functions in the central and peripheral nervous systems, and NK1R antagonists such as aprepitant have been approved for treating chemotherapy-induced nausea and vomiting. However, the lack of data on NK1R structure and biochemistry has limited further drug development targeting this receptor. Here, we combine NMR spectroscopy and X-ray crystallography to provide dynamic and static characterisation of the binding mode of aprepitant in complexes with human NK1R variants. 19F-NMR showed a slow off-rate in the binding site, where aprepitant occupies multiple substates that exchange with frequencies in the millisecond range. The environment of the bound ligand is affected by the amino acid in position 2.50, which plays a key role in ligand binding and receptor signaling in class A GPCRs. Crystal structures now reveal how receptor signaling relates to the conformation of the conserved NP7.50xxY motif in transmembrane helix VII.

Structural basis for ligand recognition of the human thromboxane A2 receptor.

Stimulated by thromboxane A2, an endogenous arachidonic acid metabolite, the thromboxane A2 receptor (TP) plays a pivotal role in cardiovascular homeostasis, and thus is considered as an important drug target for cardiovascular disease. Here, we report crystal structures of the human TP bound to two nonprostanoid antagonists, ramatroban and daltroban, at 2.5 Å and 3.0 Å resolution, respectively. The TP structures reveal a ligand-binding pocket capped by two layers of extracellular loops that are stabilized by two disulfide bonds, limiting ligand access from the extracellular milieu. These structures provide details of interactions between the receptor and antagonists, which help to integrate previous mutagenesis and SAR data. Molecular docking of prostanoid-like ligands, combined with mutagenesis, ligand-binding and functional assays, suggests a prostanoid binding mode that may also be adopted by other prostanoid receptors. These insights into TP deepen our understanding about ligand recognition and selectivity mechanisms of this physiologically important receptor.

Fluorescence spectrum photo-bleaching analysis for distinguishing microorganisms (bacteria and fungi) from other particles in air.

A new device with a 405 nm blue laser diode is developed for collecting samples in air and detecting their spectra variation. The multi-sample particles which are pure microorganisms can be distinguished from interferents in the air by photo-bleaching phenomenon. Six types of microorganisms and twelve types of interferents from the air, which exhibit laser-induced fluorescence, are used to evaluate the performance of the analysis approach, and their fluorescence emission spectra are presented. The results show that when microorganisms are illuminated by the laser, the fluorescence spectra will change significantly within several minutes, including both the wavelength of the main peak and fluorescence intensity. Our work provides a potential approach to distinguish microorganisms from other particles by the changes.

Pain beliefs mediate relations between general resilience and dysfunction from chronic back pain.

PURPOSE/OBJECTIVE: A substantial percentage of people affected by chronic back pain maintain a high quality of life despite ongoing discomfort. Presumably, more resilient persons view pain and their capacities to manage it in a manner that mitigates pain-related dysfunction. Research Method/Design: To test this premise, 307 mainland Chinese adults with chronic back pain (189 women, 118 men) completed self-report measures of psychological resilience, pain beliefs (challenge appraisals of pain, pain self-efficacy, pain catastrophizing) and pain-related dysfunction (i.e., pain intensity, disability, affective distress, depression) within a cross-sectional research design. RESULTS: Structural equation modeling indicated elevations in general psychological resilience were related to more frequent appraisals of pain as a challenge, higher pain self-efficacy levels, and lower pain catastrophizing levels. In turn, resilience, pain self-efficacy, and pain catastrophizing were linked to pain-related dysfunction while challenge appraisals were not. CONCLUSIONS/IMPLICATIONS: Together, results underscored specific pain beliefs underlying the pathway between resilience and reduced dysfunction from chronic back pain. Aside from evaluating dysfunctional expectancies (e.g., pain catastrophizing) and outcomes, practitioners and researchers should consider beliefs about personal effectiveness in managing pain within assessment and treatment protocols of chronic back pain. (PsycINFO Database Record (c) 2018 APA, all rights reserved).