The ZAR1 resistosome is a calcium-permeable channel triggering plant immune signaling.

Nucleotide-binding, leucine-rich repeat receptors (NLRs) are major immune receptors in plants and animals. Upon activation, the Arabidopsis NLR protein ZAR1 forms a pentameric resistosome in vitro and triggers immune responses and cell death in plants. In this study, we employed single-molecule imaging to show that the activated ZAR1 protein can form pentameric complexes in the plasma membrane. The ZAR1 resistosome displayed ion channel activity in Xenopus oocytes in a manner dependent on a conserved acidic residue Glu11 situated in the channel pore. Pre-assembled ZAR1 resistosome was readily incorporated into planar lipid-bilayers and displayed calcium-permeable cation-selective channel activity. Furthermore, we show that activation of ZAR1 in the plant cell led to Glu11-dependent Ca2+ influx, perturbation of subcellular structures, production of reactive oxygen species, and cell death. The results thus support that the ZAR1 resistosome acts as a calcium-permeable cation channel to trigger immunity and cell death.

Effect of Project Orbis participation by the Swiss regulator on submission gaps, review times, and drug approval decisions between 2020 and 2022: a comparative analysis.

BACKGROUND: Expedited market access for novel and efficacious drugs is warranted for patients. Since 2020, Swissmedic (The Swiss Agency for Therapeutic Products) has been participating in Project Orbis, a collaborative parallel-review programme launched by the US Food and Drug Administration (FDA) in 2019 to expedite patient access to cancer drugs. This programme allows regulatory agencies to remain independent in their decisions. We aimed to evaluate the effect of the first 2 years of Project Orbis from the Swissmedic perspective. METHODS: In this comparative analysis, we compared submission gap (time between submission at the FDA and Swissmedic), review time, approval and consensus decision rate, and the approved indications between Swissmedic and the FDA for marketing authorisation applications (MAAs) in oncology submitted to Swissmedic through Project Orbis (Orbis MAAs) or outside of Project Orbis (non-Orbis MAAs) from Jan 1, 2020, to Dec 31, 2021. Swissmedic review time was evaluated with a decision until June 30, 2022. For the decision comparison analysis, non-Orbis oncology MAAs submitted and evaluated from Jan 1, 2009, to Dec 31, 2018 (referred to as the pre-Orbis era) were also considered. Inferential statistics were done using Wilcoxon rank-sum test and the 95% CI for the median was based on binomial distribution. For each hypothesis testing, the significance level was set to 5%. No correction for multiple testing was performed. FINDINGS: We analysed the submission gap, review time, and regulatory decision for 31 Orbis MAAs and 41 non-Orbis MAAs during the Orbis era. The median submission gap was 33·0 days (95% CI 19·0-57·0) for Orbis MAAs versus 168·0 days (56·0-351·0) for non-Orbis MAAs (p<0·0001). The median review time at Swissmedic was 235·5 days (198·0-264·0) for Orbis MAAs versus 314·0 days (279·0-354·0) for non-Orbis MAAs (p=0·0002). Approval rates at Swissmedic were consistent between Orbis MAAs (20 [77%] of 26) and non-Orbis MAAs (31 [76%] of 41). The rate of consensus decisions between Swissmedic and the FDA was 21 (81%) of 26 for Orbis MAAs and 31 (76%) of 41 for non-Orbis MAAs. Swissmedic approval rates were lower for indication extensions than for new active substances for Orbis MAAs (13 [72%] of 18 vs seven [88%] of eight) and non-Orbis MAAs (17 [71%] of 24 vs 14 [82%] of 17). Divergent decisions between agencies were predominantly observed for indication extensions (11 [73%] of 15 divergent decisions). During the pre-Orbis era, Swissmedic approved 61 (88%) of 69 MAAs for new active substances. INTERPRETATION: Submission gap and review time for oncology applications at Swissmedic were significantly reduced by participation in Project Orbis, and approval consensus decisions were increased between agencies. These findings suggests that participating in Project Orbis could lead to faster patient access to drugs. FUNDING: None.

Pinacidil ameliorates cardiac microvascular ischemia-reperfusion injury by inhibiting chaperone-mediated autophagy of calreticulin.

Calcium overload is the key trigger in cardiac microvascular ischemia-reperfusion (I/R) injury, and calreticulin (CRT) is a calcium buffering protein located in the endoplasmic reticulum (ER). Additionally, the role of pinacidil, an antihypertensive drug, in protecting cardiac microcirculation against I/R injury has not been investigated. Hence, this study aimed to explore the benefits of pinacidil on cardiac microvascular I/R injury with a focus on endothelial calcium homeostasis and CRT signaling. Cardiac vascular perfusion and no-reflow area were assessed using FITC-lectin perfusion assay and Thioflavin-S staining. Endothelial calcium homeostasis, CRT-IP3Rs-MCU signaling expression, and apoptosis were assessed by real-time calcium signal reporter GCaMP8, western blotting, and fluorescence staining. Drug affinity-responsive target stability (DARTS) assay was adopted to detect proteins that directly bind to pinacidil. The present study found pinacidil treatment improved capillary density and perfusion, reduced no-reflow and infraction areas, and improved cardiac function and hemodynamics after I/R injury. These benefits were attributed to the ability of pinacidil to alleviate calcium overload and mitochondria-dependent apoptosis in cardiac microvascular endothelial cells (CMECs). Moreover, the DARTS assay showed that pinacidil directly binds to HSP90, through which it inhibits chaperone-mediated autophagy (CMA) degradation of CRT. CRT overexpression inhibited IP3Rs and MCU expression, reduced mitochondrial calcium inflow and mitochondrial injury, and suppressed endothelial apoptosis. Importantly, endothelial-specific overexpression of CRT shared similar benefits with pinacidil on cardiovascular protection against I/R injury. In conclusion, our data indicate that pinacidil attenuated microvascular I/R injury potentially through improving CRT degradation and endothelial calcium overload.

Decision-making at Swissmedic, the Swiss regulatory agency, with a focus on (neo)adjuvant cancer treatments.

INTRODUCTION: Additional considerations are required for the benefit-risk assessment of new drugs or indications in the setting of (neo)adjuvant cancer treatment as compared to the metastatic/advanced setting, possibly leading to different decision patterns for the (neo)adjuvant versus the metastatic and advanced setting within a health authority but also among different health authorities. METHODS: We analyzed regulatory decisions at the Swiss Agency for Therapeutic Products Swissmedic (SMC) for all oncology indications (mostly metastatic indications) and indications in the (neo)adjuvant setting and compared these to decisions taken by the European Medicines Agency (EMA) and the United States Food and Drug Administration (FDA). RESULTS: Comparing the positive and negative decisions within the Swiss Agency for Therapeutic Products Swissmedic (SMC) between July 2017 and Dec 2021 the approval rates were with 66.7% lower for (neo)adjuvant indications versus 88.4% in the metastatic and advanced indications. While the approval rates for metastatic and advanced New Active Substances (NAS) applications were similar at SMC as compared to the EMA and the FDA, they were lower for (neo)adjuvant applications at SMC as compared to the EMA and the FDA. The underlying reason in all cases with divergent decisions at SMC as compared to EMA and FDA was that no overall survival (OS) benefit as compared to control arm has been observed in the submitted data package. CONCLUSION: Approval and consensus decision rates at SMC in comparison to EMA and FDA were lower for (neo)adjuvant indications but not for advanced and metastastic NAS oncology indications.

Nicorandil alleviates cardiac microvascular ferroptosis in diabetic cardiomyopathy: Role of the mitochondria-localized AMPK-Parkin-ACSL4 signaling pathway.

Mitochondria-associated ferroptosis exacerbates cardiac microvascular dysfunction in diabetic cardiomyopathy (DCM). Nicorandil, an ATP-sensitive K+ channel opener, protects against endothelial dysfunction, mitochondrial dysfunction, and DCM; however, its effects on ferroptosis and mitophagy remain unexplored. The present study aimed to assess the beneficial effects of nicorandil against endothelial ferroptosis in DCM and the underlying mechanisms. Cardiac microvascular perfusion was assessed using a lectin perfusion assay, while mitophagy was assessed via mt-Keima transfection and transmission electron microscopy. Ferroptosis was examined using mRNA sequencing, fluorescence staining, and western blotting. The mitochondrial localization of Parkin, ACSL4, and AMPK was determined via immunofluorescence staining. Following long-term diabetes, nicorandil treatment improved cardiac function and remodeling by alleviating cardiac microvascular injuries, as evidenced by the improved microvascular perfusion and structural integrity. mRNA-sequencing and biochemical analyses showed that ferroptosis occurred and Pink1/Parkin-dependent mitophagy was suppressed in cardiac microvascular endothelial cells after diabetes. Nicorandil treatment suppressed mitochondria-associated ferroptosis by promoting the Pink1/Parkin-dependent mitophagy. Moreover, nicorandil treatment increased the phosphorylation level of AMPKα1 and promoted its mitochondrial translocation, which further inhibited the mitochondrial translocation of ACSL4 via mitophagy and ultimately suppressed mitochondria-associated ferroptosis. Importantly, overexpression of mitochondria-localized AMPKα1 (mitoAα1) shared similar benefits with nicorandil on mitophagy, ferroptosis and cardiovascular protection against diabetic injury. In conclusion, the present study demonstrated the therapeutic effects of nicorandil against cardiac microvascular ferroptosis in DCM and revealed that the mitochondria-localized AMPK-Parkin-ACSL4 signaling pathway mediates mitochondria-associated ferroptosis and the development of cardiac microvascular dysfunction.

Structure and activity of SLAC1 channels for stomatal signaling in leaves.

Stomata in leaves regulate gas exchange between the plant and its atmosphere. Various environmental stimuli elicit abscisic acid (ABA); ABA leads to phosphoactivation of slow anion channel 1 (SLAC1); SLAC1 activity reduces turgor pressure in aperture-defining guard cells; and stomatal closure ensues. We used electrophysiology for functional characterizations of Arabidopsis thaliana SLAC1 (AtSLAC1) and cryoelectron microscopy (cryo-EM) for structural analysis of Brachypodium distachyon SLAC1 (BdSLAC1), at 2.97-Å resolution. We identified 14 phosphorylation sites in AtSLAC1 and showed nearly 330-fold channel-activity enhancement with 4 to 6 of these phosphorylated. Seven SLAC1-conserved arginines are poised in BdSLAC1 for regulatory interaction with the N-terminal extension. This BdSLAC1 structure has its pores closed, in a basal state, spring loaded by phenylalanyl residues in high-energy conformations. SLAC1 phosphorylation fine-tunes an equilibrium between basal and activated SLAC1 trimers, thereby controlling the degree of stomatal opening.

Using the Unified Theory of Acceptance and Use of Technology (UTAUT) and e-health literacy(e-HL) to investigate the tobacco control intentions and behaviors of non-smoking college students in China: a cross-sectional investigation.

BACKGROUND: Non-smoking college students are starting to smoke in increasing numbers, which shows that their tobacco control situation seems not optimistic. The UTAUT and e-HL are commonly used models and theories to predict health behaviors, while there are few studies on tobacco control. This paper aims to study the influencing factors of tobacco control intention and behavior of non-smoking college students in China by combining the UTAUT and e-HL. METHODS: Based on the stratified sampling method, 625 college students from 12 universities were selected. Data were collected using a self-made questionnaire designed based on the UTAUT and e-health literacy scales. Data were analyzed by SPSS 22 and AMOS 26, including descriptive statistics, one-way variance analysis and structural equation model analysis. RESULTS: The results of one-way variance analysis showed that there were significant differences in the score of non-smoking college students' tobacco control intention or behavior by hometowns, monthly living expenses, and parents' smoking history. Performance expectancy, effort expectancy, social influence had direct positive effects on behavioral intention. Facilitating condition, behavioral intention had direct positive impacts on use behavior and e-HL had an indirect positive impact on use behavior. CONCLUSIONS: The combination of the UTAUT and e-HL can be used as an appropriate framework to predict the influencing factors of non-smoking college students' intention and behavior of tobacco control. Improving performance expectancy, effort expectancy, and e-HL among non-smoking college students, creating positive social environments, and providing facilitating condition are key aspects of increasing their tobacco control intention and behavior. It is also beneficial to promote the implementation of smoke-free campus and smoke-free family projects.

Exploring factors that influence the behavioural intention of medical students to use 3D gastroscopic model to learn how to operate gastroscope using UTAUT Model.

BACKGROUND: The application of virtual reality (VR) in gastroscopic operation teaching can be safe and effective, but the advantages can be realized only when students accept and use it. This study aims to identify the factors influencing Chinese clinical medical postgraduates on their intention to use the 3D gastroscopic model constructed based on VR technology using Unified Theory of Acceptance and Use of Technology (UTAUT) model. Students' demographic factors are also taken into consideration. METHODS: All methods were carried out in accordance with relevant guidelines. Data were collected from clinical medical postgraduates students in China using stratified sampling. A total of 292 questionnaires including valid responses were used in this study. Data were processed using Amos 24.0 and SPSS 26.0 software and the statistical analysis technique was based on structural equation modeling (SEM). RESULTS: The results showed that different from the mediator of home location and year of clinical learning, mediator of gender, university kind and graduate degree did not affect the behavioral intention. In addition, performance expectancy, facilitating condition, and social influence directly and indirectly have effect on behavioral intention. Also, the significance between social influence and performance expectancy, social influence and effort expectancy were verified. CONCLUSIONS: This study manifested that the proposed framework based on the UTAUT had explanatory power to identify the factors influencing the students' behavioral intention to use the 3D gastroscopic model constructed based on VR technology. Whereas, an important variable of effort expectancy in the frame of the SEM were not certified, thereby indicating that particular attention should be paid to this variable by universities and teachers before applying 3D gastroscopic model constructed based on VR technology in teaching. Added preparatory work is required such as explaining the basic knowledge of the operating steps of VR model and make students adequately understand its accessibility, which can probably improve the intentions of them to use it. The positive effects of social influence on performance expectancy and effort expectancy we proposed was also verified in this study, which provided a direction for future research.

Wound cosmesis problems and other postoperative problems of laparoscopic compared to open paediatric inguinal hernia repair: A meta-analysis.

A meta-analysis research was executed to appraise the wound cosmesis problems and other postoperative problems of laparoscopic compared to open paediatric inguinal hernia (IH) repair. Inclusive literature research until March 2023 was done and 869 interconnected researches were revised. The 11 picked researches enclosed 3718 paediatric inguinal hernia were in the utilised researches' starting point, 1948 of them were utilising laparoscopic IH repairs, and 1770 were utilising open IH repairs. Odds ratios (ORs) in addition to 95% confidence intervals (CIs) were utilised to appraise the wound cosmesis problems and other postoperative problems of laparoscopic compared to open paediatric IH repairs by dichotomous approaches and a fixed or random model. Laparoscopic IH repairs had significantly lower wound cosmesis problems (OR, 0.29; 95% CI, 0.16-0.52, P < .001), metachronous contralateral inguinal hernia (MCIH) (OR, 0.11; 95% CI, 0.03-0.49, P = .003), recurrence (OR, 0.34; 95% CI, 0.34-0.99, P = .04) and postoperative problems (OR, 0.35; 95% CI, 0.17-0.73, P = .005), and higher wound score (OR, 12.80; 95% CI, 10.09-15.51, P < .001) compared to open paediatric IH. Laparoscopic IH repairs had significantly lower wound cosmesis problems, MCIH, recurrence, and postoperative problems, and a higher wound score compared to open paediatric IH. However, when interacting with its values, caution must be taken since much of the research had low sample sizes.

Association of occupational stress, period circadian regulator 3 (PER3) gene polymorphism and their interaction with poor sleep quality.

Occupational stress is associated with sleep quality among workers and the human variable number tandem repeat (VNTR) polymorphism of the period circadian regulator 3 (PER3) gene relates to sleep-wake regulation. The main aims of the present study were to examine the effects of PER3 VNTR genotypes, occupational stress, and their interactions on sleep quality. A cross-sectional study was conducted and 729 workers were recruited in Sichuan. Sleep quality were assessed using the Pittsburgh Sleep Quality Index. Occupational stress was measured using the Generic Job Stress Questionnaire. PER3 genotypes were determined with polymerase chain reaction. High and medium occupational stress were linked to a higher risk of poor sleep quality than low levels. Unconditional logistic regression indicated that PER3 genotype was significantly associated with sleep quality, and an increased risk of poor sleep of >1.5-times was observed in those with the allele 5 compared to allele 4. The 5/5 genotype was associated with both sleep latency and sleep duration. Crossover analysis showed an occupational stress × PER3 interaction. Compared to subjects with both low and medium occupational stress and 4/4 + 4/5 genotype, those with both high occupational stress and 5/5 genotype had a higher risk of poor sleep quality. Stratified logistic analyses found that compared with low and medium occupational stress, high occupational stress increased the risk of poor sleep by more than five-times in 5/5 genotype carriers. Occupational stress and PER3 genotype had both separate and combined effects on poor sleep quality of workers. The results suggest that occupational stress may increase the risk of poor sleep quality through interaction with the PER3 gene polymorphism.

Targeted neutrophil-mimetic liposomes promote cardiac repair by adsorbing proinflammatory cytokines and regulating the immune microenvironment.

Acute myocardial infarction (MI) induces a sterile inflammatory response that may result in poor cardiac remodeling and dysfunction. Despite the progress in anti-cytokine biologics, anti-inflammation therapy of MI remains unsatisfactory, due largely to the lack of targeting and the complexity of cytokine interactions. Based on the nature of inflammatory chemotaxis and the cytokine-binding properties of neutrophils, we fabricated biomimetic nanoparticles for targeted and broad-spectrum anti-inflammation therapy of MI. By fusing neutrophil membranes with conventional liposomes, we fabricated biomimetic liposomes (Neu-LPs) that inherited the surface antigens of the source cells, making them ideal decoys of neutrophil-targeted biological molecules. Based on their abundant chemokine and cytokine membrane receptors, Neu-LPs targeted infarcted hearts, neutralized proinflammatory cytokines, and thus suppressed intense inflammation and regulated the immune microenvironment. Consequently, Neu-LPs showed significant therapeutic efficacy by providing cardiac protection and promoting angiogenesis in a mouse model of myocardial ischemia-reperfusion. Therefore, Neu-LPs have high clinical translation potential and could be developed as an anti-inflammatory agent to remove broad-spectrum inflammatory cytokines during MI and other neutrophil-involved diseases.

Targeted delivery and ROS-responsive release of Resolvin D1 by platelet chimeric liposome ameliorates myocardial ischemia-reperfusion injury.

Resolvin D1 (RvD1) has been shown to provide effective protection against ischemia-reperfusion injury in multiple vital organs such as the heart, brain, kidney. However, the clinical translational potential of systemic administration of RvD1 in the treatment of ischemia-reperfusion injury is greatly limited due to biological instability and lack of targeting ability. Combining the natural inflammatory response and reactive oxygen species (ROS) overproduction after reperfusion injury, we developed a platelet-bionic, ROS-responsive RvD1 delivery platform. The resulting formulation enables targeted delivery of RvD1 to the injury site by hijacking circulating chemotactic monocytes, while achieving locally controlled release. In a mouse model of myocardial ischemia repefusuin (MI/R) injury, intravenous injection of our formula resulted in the enrichment of RvD1 in the injured area, which in turn promotes clearance of dead cells, production of specialized proresolving mediators (SPMs), and angiogenesis during injury repair, effectively improving cardiac function. This delivery system integrates drug bio-protection, targeted delivery and controlled release, which endow it with great clinical translational value.

Negative emotional status and influencing factors among young employees in center of disease control and prevention.

BACKGROUND: Negative emotions among employees have become a public problem that increase the risk of developing the disease and accelerate its progression. This study aimed to investigate the status and influencing factors of negative emotions among young employees in center of disease control and prevention. METHODS: Participants included 6099 employees aged 40 or below in center of disease control and prevention (CDC) of 32 province of China were interviewed by online questionnaire survey. The emotional conditions of anxiety and depression, and their influencing factors were analyzed. RESULTS: A total of 5353 valid questionnaires were collected with the recovery rate of 87.77%. 2871 cases of young employees had different degrees of negative emotions at work, accounting for about 53.60%. Regression analysis showed that gender, professional title, educational level, job satisfaction, chronic diseases, daily sleep duration, average weekly overtime, physical activity time, and sugary beverage intake were the influencing factors of negative emotions (P < 0.05). Male, primary and below, never working overtime and daily physical activity time more than 30 min were protective factors for negative emotions (OR vale were 0.79, 0.68, 0.39 and 0.63, respectively, P < 0.05). Bachelor degree or above, poor job satisfaction, chronic disease, daily sleep duration less than 8 h and drinking one to three sugary drinks a week were the risk factors for negative emotion (OR vale were1.21, 4.32, 2.16, 2.75 and 1.20, respectively, P < 0.05). CONCLUSION: Due to the influence of work pressure, lifestyle, chronic diseases and other factors, young employees in CDC have a certain degree of negative emotions at work, which should be paid enough attention. Meanwhile, corresponding measures should be taken according to the influencing factors to reduce the occurrence of negative emotions.

Fetal endoscopic tracheal occlusion for moderate and severe congenital diaphragmatic hernia: a systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: Fetoscopic endoluminal tracheal occlusion (FETO) is considered to increase survival among fetuses with congenital diaphragmatic hernia (CDH). Data from high-quality trials had been lacking until the largest randomized controlled trials (the TOTAL trials) were completed. This study aimed to elucidate the efficacy and safety of FETO for increasing the survival of fetuses with moderate or severe CDH. METHODS: Relevant studies published before August 1st, 2021 were identified by searching PubMed, Cochrane Library and Web of Science. Only randomized controlled trials (RCTs) reporting patients who underwent FETO versus patients who received standard perinatal care were included in the analysis. The primary outcome was survival in the FETO and control groups. The secondary aim was to evaluate complications during pregnancy, such as premature rupture of membranes (PROM) and preterm delivery, and neonatal complications, including the need for supplemental oxygen at birth and discharge and pulmonary hypertension in the FETO and control groups. The Mantel-Haenszel random effects model was applied, and risk ratios (RRs) or odds ratios (ORs) were calculated. RESULTS: Four RCTs were eligible for inclusion. The quality of these studies was high. The pooled estimate of survival for fetuses with moderate or severe CDH was higher in the FETO group than in the control group [odds ratio (OR), 3.43; 95% confidence interval (CI), 1.12-10.48; P = 0.03] with relatively strong evidence of between-study heterogeneity (I2 = 66%). Subgroup analysis revealed that in the severe CDH group, the pooled estimates of neonatal survival were significantly higher in the FETO group than in the control group (OR, 6.57; 95% CI, 1.39-31.06; P = 0.02). However, in the moderate CDH group, the pooled results of neonatal survival were only slightly higher in the FETO group than in the control group (OR, 1.65; 95% CI, 0.93-2.91; P = 0.08) and the difference was not significant. The risks of PROM and preterm delivery were both higher in the FETO group. No significant difference was found for the need for supplemental oxygen at birth and discharge or in pulmonary hypertension between the FETO group and matched controls. A limitation is that we were unable to calculate the effect of the second intervention on prematurity, which would have been meaningful for evaluating the risk of FETO for PROM or preterm delivery. CONCLUSION: FETO increases the survival rate in fetuses with moderate and severe CDH, especially in fetuses with severe CDH. However, FETO is associated with a higher risk of PROM and preterm delivery, and the optimal time of FETO should be carefully chosen.

Protective effect of HINT2 on mitochondrial function via repressing MCU complex activation attenuates cardiac microvascular ischemia-reperfusion injury.

Current evidence indicates that coronary microcirculation is a key target for protecting against cardiac ischemia-reperfusion (I/R) injury. Mitochondrial calcium uniporter (MCU) complex activation and mitochondrial calcium ([Ca2+]m) overload are underlying mechanisms involved in cardiovascular disease. Histidine triad nucleotide-binding 2 (HINT2) has been reported to modulate [Ca2+]m via the MCU complex, and our previous work demonstrated that HINT2 improved cardiomyocyte survival and preserved heart function in mice with cardiac ischemia. This study aimed to explore the benefits of HINT2 on cardiac microcirculation in I/R injury with a focus on mitochondria, the MCU complex, and [Ca2+]m overload in endothelial cells. The present work demonstrated that HINT2 overexpression significantly reduced the no-reflow area and improved microvascular perfusion in I/R-injured mouse hearts, potentially by promoting endothelial nitric oxide synthase (eNOS) expression and phosphorylation. Microvascular barrier function was compromised by reperfusion injury, but was repaired by HINT2 overexpression via inhibiting VE-Cadherin phosphorylation at Tyr731 and enhancing the VE-Cadherin/ß-Catenin interaction. In addition, HINT2 overexpression inhibited the inflammatory response by suppressing vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1). Mitochondrial fission occurred in cardiac microvascular endothelial cells (CMECs) subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) injury and resulted in mitochondrial dysfunction and mitochondrion-dependent apoptosis, the effects of which were largely relieved by HINT2 overexpression. Additional experiments confirmed that [Ca2+]m overload was an initiating factor for mitochondrial fission and that HINT2 suppressed [Ca2+]m overload via modulation of the MCU complex through directly interacting with MCU in CMECs. Regaining [Ca2+]m overload by spermine, an MCU agonist, abolished all the protective effects of HINT2 on OGD/R-injured CMECs and I/R-injured cardiac microcirculation. In conclusion, the present report demonstrated that HINT2 overexpression inhibited MCU complex-mitochondrial calcium overload-mitochondrial fission and apoptosis pathway, and thereby attenuated cardiac microvascular ischemia-reperfusion injury.

Effects of lenalidomide on the bone marrow microenvironment in acute myeloid leukemia: Translational analysis of the HOVON103 AML/SAKK30/10 Swiss trial cohort.

This translational study aimed at gaining insight into the effects of lenalidomide in acute myeloid leukemia (AML). Forty-one AML patients aged 66 or older of the Swiss cohort of the HOVON-103 AML/SAKK30/10 study were included. After randomization, they received standard induction chemotherapy with or without lenalidomide. Bone marrow biopsies at diagnosis and before the 2nd induction cycle were obtained to assess the therapeutic impact on leukemic blasts and microenvironment. Increased bone marrow angiogenesis, as assessed by microvessel density (MVD), was found at AML diagnosis and differed significantly between the WHO categories. Morphological analysis revealed a higher initial MVD in AML with myelodysplasia-related changes (AML-MRC) and a more substantial decrease of microvascularization after lenalidomide exposure. A slight increase of T-bet-positive TH1-equivalents was identifiable under lenalidomide. In the subgroup of patients with AML-MRC, the progression-free survival differed between the two treatment regimens, showing a potential but not significant benefit of lenalidomide. We found no correlation between the cereblon genotype (the target of lenalidomide) and treatment response or prognosis. In conclusion, addition of lenalidomide may be beneficial to elderly patients suffering from AML-MRC, where it leads to a reduction of microvascularization and, probably, to an intensified specific T cell-driven anti-leukemic response.

PEG Linker Improves Antitumor Efficacy and Safety of Affibody-Based Drug Conjugates.

Antibody drug conjugates (ADCs) have become an important modality of clinical cancer treatment. However, traditional ADCs have some limitations, such as reduced permeability in solid tumors due to the high molecular weight of monoclonal antibodies, difficulty in preparation and heterogeneity of products due to the high drug/antibody ratio (4-8 small molecules per antibody). Miniaturized ADCs may be a potential solution, although their short circulation half-life may lead to new problems. In this study, we propose a novel design strategy for miniaturized ADCs in which drug molecules and small ligand proteins are site-specifically coupled via a bifunctional poly(ethylene glycol) (PEG) chain. The results showed that the inserted PEG chains significantly prolonged the circulation half-life but also obviously reduced the cytotoxicity of the conjugates. Compared with the conjugate ZHER2-SMCC-MMAE (HM), which has no PEG insertion, ZHER2-PEG4K-MMAE (HP4KM) and ZHER2-PEG10K-MMAE (HP10KM) with 4 or 10 kDa PEG insertions have 2.5- and 11.2-fold half-life extensions and 4.5- and 22-fold in vitro cytotoxicity reductions, respectively. The combined effect leads to HP10KM having the most ideal tumor therapeutic ability at the same dosages in the animal model, and its off-target toxicity was also reduced by more than 4 times compared with that of HM. These results may indicate that prolonging the half-life is very helpful in improving the therapeutic capacity of miniaturized ADCs. In the future, the design of better strategies that can prolong half-life without affecting cytotoxicity may be useful for further improving the therapeutic potential of these molecules.

A Single-Domain Antibody-Based Anti-PSMA Recombinant Immunotoxin Exhibits Specificity and Efficacy for Prostate Cancer Therapy.

Prostate cancer (PCa) is the second most common cancer in men, causing more than 300,000 deaths every year worldwide. Due to their superior cell-killing ability and the relative simplicity of their preparation, immunotoxin molecules have great potential in the clinical treatment of cancer, and several such molecules have been approved for clinical application. In this study, we adopted a relatively simple strategy based on a single-domain antibody (sdAb) and an improved Pseudomonas exotoxin A (PE) toxin (PE24X7) to prepare a safer immunotoxin against prostate-specific membrane antigen (PSMA) for PCa treatment. The designed anti-PSMA immunotoxin, JVM-PE24X7, was conveniently prepared in its soluble form in an Escherichia coli (E. coli) system, avoiding the complex renaturation process needed for immunotoxin preparation by the conventional strategy. The product was very stable and showed a very strong ability to bind the PSMA receptor. Cytotoxicity assays showed that this molecule at a very low concentration could kill PSMA-positive PCa cells, with an EC50 value (concentration at which the cell viability decreased by 50%) of 15.3 pM against PSMA-positive LNCaP cells. Moreover, this molecule showed very good killing selectivity between PSMA-positive and PSMA-negative cells, with a selection ratio of more than 300-fold. Animal studies showed that this molecule at a very low dosage (5 × 0.5 mg/kg once every three days) completely inhibited the growth of PCa tumors, and the maximum tolerable dose (MTD) was more than 15 mg/kg, indicating its very potent tumor-treatment ability and a wide therapeutic window. Use of the new PE toxin, PE24X7, as the effector moiety significantly reduced off-target toxicity and improved the therapeutic window of the immunotoxin. The above results demonstrate that the designed anti-PSMA immunotoxin, JVM-PE24X7, has good application value for the treatment of PCa.

Modification with CREKA Improves Cell Retention in a Rat Model of Myocardial Ischemia Reperfusion.

Poor cell homing limits the efficacy of cardiac cellular therapy. The homing peptide, cysteine-arginine-glutamic acid-lysine-alanine (CREKA), targets fibrin effectively which is involved in the repair process of tissue injury. Here, we assessed if CREKA-modified stem cells had enhanced fibrin-mediated homing ability resulting in better functional recovery and structural preservation in a rat myocardial injury model. CREKA-modified mesenchymal stem cells (CREKA-MSCs) were obtained via membrane fusion with CREKA-modified liposomes. The fibrin targeting ability of CREKA-MSCs was examined both in vitro and in vivo. Under both static and flow conditions in vitro, CREKA significantly enhanced MSCs binding ability to fibrin clots (2.6- and 2.3-fold, respectively). CREKA-MSCs showed 6.5-fold higher accumulation than unmodified MSCs in injured rat myocardium one day after administration, resulting in better structural preservation and functional recovery. Fibrin is, therefore, a novel target for enhancing homing of transplanted cells to injured myocardium, and the delivery system of fibrin-targeting is on behalf of a universalizable platform technology for regenerative medicine. Stem Cells 2019;37:663-676.

Lysine Mutation of the Claw-Arm-Like Loop Accelerates Catalysis by Cellobiohydrolases.

Searching for viable strategies to accelerate the catalytic cycle of glycoside hydrolase family 7 (GH7) cellobiohydrolase I (CBHI)-the workhorse cellulose-degrading enzymes, we have performed a total of 12-µs molecular dynamics simulations on GH7 CBHI, which brought to light a new mechanism for cellobiose expulsion, coined "claw-arm" action. The loop flanking the product binding site plays the role of a flexible "arm" extending toward cellobiose, and residue Thr389 of this loop acts as a "claw" that captures cellobiose. Five mutations of residue Thr389 were considered to enhance the loop-cellobiose interaction. The lysine mutant was found to significantly accelerate cellobiose expulsion and facilitate polysaccharide-chain translocation. Lysine mutation of Thr393 in Talaromyces emersonii CBHI (TeCel7A) performed similarly. Lysine approaches the catalytic area and stabilizes the Michaelis complex, potentially affecting glycosylation, the rate-limiting step of the catalytic cycle. QM/MM calculations indicate that lysine replacement diminishes the barrier against proton transfer, the crucial step of glycosylation, by 2.3 kcal/mol. Experimental validation was performed using the full-length wild-type (WT) of TeCel7A and its mutants, recombinantly expressed in Pichia pastoris, to degrade the substrates. Compared with the WT, the lysine mutant revealed an associated higher enzymatic reaction rate. Furthermore, cellobiose yield was also increased by lysine mutation, indicating that dissociation of the enzyme from cellulose was accelerated, which largely stems from the enhanced flexibility of the "arm". The present work is envisioned to help design strategies for improving enzymatic activity, while decreasing enzyme cost.