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This paper investigates the security control of a class of discrete-time Markov jump systems (DMJS). Due to the vulnerability of open communication networks to cyber attacks, a hybrid attack model is established to describe the situation where the DMJS is simultaneously suffered from deception attacks (DAs) and denial-of-service (DoS) attacks. To cope with the intermittent characteristic of DoS attacks, adaptive memory-based event-triggered control (AMETC) with a switching-like adaptive law is proposed. The designed AMETC includes historical triggered data in its triggering condition, hence allows data transmission to adjust adaptively based on the long-term change of system state. In addition, when DoS attacks are launched by attackers, the designed switching-like adaptive law can help decrease the threshold to trigger more sampled data so as to stabilize the DMJS. These features contribute to improve the tolerance of the whole control system to DoS attacks and DAs. On the basis of the AMETC, a novel Lyapunov functional is designed, and sufficient conditions are derived to ensure the asymptotic stability of DMJSs. This functional plays a crucial role in ensuring the negative definiteness of the LMIs in the stability condition. Based on the stability condition, a design algorithm for security control gains and event-trigger matrices is given. Finally, simulation results validate the effectiveness and superiority of the proposed mechanism. Note to Practitioners—This paper was motivated by existing results on memory-based event-triggered control (METC) and hybrid cyber attacks. The aim of this paper is to design a novel AMETC with a switching-like adaptive law to cope with the impact of hybrid attacks on system performance. In practical applications, if the event-triggered mechanism only considers the transient information of the system, it may lead to high peak responses of the control systems, resulting in a decrease in system performance. Therefore, the AMETC proposed in this paper considers both the transient information and the long-term state change of the system. It can adjust the data transmission rate adaptively and save transmission resources effectively. Additionally, based on the designed AMETC, sufficient conditions are obtained to ensure the safe and stable operation of DMJSs. Our theoretical analysis and simulation results show the effectiveness and superiority of the designed mechanism.

Acute respiratory distress syndrome (ARDS), a fatal critical disease, is induced by various insults. ARDS represents a major global public health burden, and the management of ARDS continues to challenge healthcare systems globally, especially during the pandemic of the coronavirus disease 2019 (COVID-19). There remains no confirmed specific pharmacotherapy for ARDS, despite advances in understanding its pathophysiology. Debate continues about the potential role of glucocorticoids (GCs) as a promising ARDS clinical therapy. Questions regarding GC agent, dose, and duration in patients with ARDS need to be answered, because of substantial variations in GC administration regimens across studies. ARDS heterogeneity likely affects the therapeutic actions of exogenous GCs. This review includes progress in determining the GC mechanisms of action and clinical applications in ARDS, especially during the COVID-19 pandemic.

The self-healing coatings for metals aroused researchers' interest due to their spontaneous repair of coating damage. In this study, intelligent damage-reporting and self-healing anti-corrosion coatings were developed using electrospun fiber as the core functional materials. The fibers exhibited core–shell structures, with the core materials being the solutions of the composite fluorescence probe RTPE. The shell materials consisted of the photothermal shape memory polymer, namely, phosphotungstic acid modified polyaniline-polyurethane composite polymer. Rhodamine Tetraphenylethylene (RTPE) demonstrated water-triggered aggregation-induced emission (AIE) effects and also exhibited fluorescence response to corrosive factors such as hydrogen ions and iron ions at the damaged area of the coatings. Under the trigger of the infrared laser, the modified polyaniline converted light energy into heat, causing the softening of epoxy and the shape memory effect of polyurethane. These processes facilitated the closure and repair of the damage, thus restoring their anti-corrosion functionality. Phosphotungstic acid played a role in enhancing the photothermal efficiency. The self-healing mechanism reinforced the corrosion resistance of the coatings. The self-indicating feature for damaged areas provided guidance for artificial repair in regions that did not self-heal satisfactorily. The synergistic and intelligent functionalities of the prepared coatings foreshadowed the significant potential applications in marine and aerospace corrosion protection fields. [ABSTRACT FROM AUTHOR]

Imaging strategies for the specific detection and therapeutic monitoring of myocarditis are still lacking. Stimulator of interferon genes (STING) is a signal transduction molecule involved in an innate immune response. Here, we evaluated the feasibility of the recently developed STING-targeted radiotracer [18F]FBTA for positron emission tomography (PET) imaging to detect myocardial inflammation and monitor treatment in myocarditis mice. [18F]FBTA-PET imaging was performed in myocarditis mice and normal mice to verify the specificity of [18F]FBTA for the diagnosis of myocarditis. We also performed PET imaging in mice with myocarditis treated to verify the ability of [18F]FBTA in therapeutic monitoring. The expression of STING and inflammatory cell types was confirmed by flow cytometry and immunohistochemistry. [18F]FDG-PET imaging of myocarditis was used as a contrast. [18F]FBTA-PET imaging showed that the average radioactive uptake was significantly higher in the hearts of the myocarditis group than in the control group. STING was highly overexpressed in cardiac inflammatory cells, including macrophages, dendritic cells (DCs), and T cells. However, there was no significant difference in cardiac radiotracer uptake of [18F]FDG between the myocarditis group and the control group. Moreover, cardiac uptake of [18F]FBTA was significantly reduced in cyclosporin A-treated myocarditis mice and myocardial STING expression was also significantly reduced after the treatment. Overall, we showed that a STING-targeted PET tracer [18F]FBTA can be used to monitor changes in the inflammatory microenvironment in myocarditis. Besides, [18F]FBTA-PET is also suitable for real-time monitoring of myocarditis treatment, representing a promising diagnostic and therapeutic monitoring approach for myocarditis.

ABSTRACTThe Particle and Heavy Ion Transport code System (PHITS) is a general-purpose Monte Carlo radiation transport code that can simulate the behavior of most particle species with energies up to 1 TeV (per nucleon for ions). Its new version, PHITS3.33, was recently developed and released to the public. In the new version, the compatibility with nuclear data libraries and the algorithm of the track-structure modes have been improved, and they are recommended to be used for certain simulation conditions. Some utility functions and software have been developed and integrated into the new PHITS package, such as PHITS Interactive Geometry viewer in 3D (PHIG-3D) and RadioTherapy packaged based on PHITS (RT-PHITS). With these upgraded features, PHITS can be applied in a wide diversity of fields – beyond traditional nuclear engineering domains – including cosmic-ray, environmental, medical, life, and material sciences. In this paper, we summarize the upgraded features of PHITS3.33 with respect to the physics models, utility functions, and application software introduced since the release of PHITS3.02 in 2017.

Widely applied aluminum alloys in ship hulls, underwater vehicles, and marine machinery experience severe corrosion in harsh marine environments. For corrosion protection of aluminum alloys, the most convenient, effective, and low-cost approach was the application of anti-corrosion coatings. Coatings possessing self-healing properties to spontaneously repair damages have emerged as a research focus for new types of coatings. In this study, focused on the indication and repair of anti-corrosion coating damages for aluminum alloys, the fluorescent aggregation-induced emission (AIE) composite probe, rhodamine-naphthalimide (RNI), was synthesized, and the composite polymer materials HPPA-SMPU containing 2-hydroxyphosphinoyl carboxylic acid-doped polyaniline and shape memory polyurethane were prepared. Coaxial electrospinning technology was introduced to combine the two and create the fibrous materials with the fiber wall constructed from HPPA-SMPU, encapsulating the interior RNI solution. The fibers were incorporated into the epoxy coatings. RNI exhibited water-triggered AIE, Al3+-CHEF (chelation-enhanced fluorescence), and pH-responsive fluorescent properties to indicate infrared laser-targeted points of coating damages. The photothermal properties of HPPA-SMPU caused localized heating of the damaged coatings, reaching the phase transition temperature of epoxy and SMPU, leading to softening, expansion, shape memory behavior, and healing of the coating damages. The self-healing approaches enhanced the protective performance of the coatings for aluminum alloys, showcasing and extending the development of synergistic and intelligent functions in novel self-healing coating technologies.

This article considers the secure control of Markovian jumping systems (MJSs) under stochastic deception attacks that occurred in the communication network. Therein, the stochastic deception attack is described by a Bernoulli random variable. Considering the limited network bandwidth and the impact of deception attacks simultaneously, we propose an attack-probability-dependent adaptive event-triggered mechanism. Not only can it reduce the number of controller updates, but it can also adapt to the variation of system dynamics subject to deception attacks. A mathematical model is established for the closed-loop system under stochastic deception attacks. Then, a time-dependent looped functional is constructed to reduce the conservatism of stability results. The norm of the system state is estimated, and based on the discrete-time Lyapunov theory, a less conservative stability criterion is derived. Then, an easy-to-implement design algorithm for the controller gain is given so that the exponential stabilization in the mean square sense can be realized for the MJS subject to stochastic deception attacks. Finally, an electrical circuit example is provided to validate the feasibility and superiority of the presented method.

Microorganisms play an important role in cigar fermentation. To further explore the dynamic changes of bacterial community composition, the changes of surface bacterial diversity of cigar filler leaves were investigated in the present study by high-throughput sequencing technology. It was found that the surface bacterial richness was declined after fermentation, and the dominant microorganisms on the surface of cigar filler leaves evolved from Pseudomonasspp. and Sphingomonasspp. before fermentation to Staphylococcusspp. after fermentation. The chemical composition and sensory quality evaluation of cigar filler leaves were closely related to the changes of surface bacterial community. The changes of the dominant surface bacterial community led to the differences of metabolic functions, among which the metabolic pathways such as the synthesis of secondary metabolites, carbon metabolism, and amino acid biosynthesis were significantly different. The results provide a basis for clarifying the roles of bacteria in fermentation of cigar filler leaves.Graphical AbstractSurface bacterial dynamic changes analysis of cigar filler leaves after fermentation revealed important role of Staphylococcusspp. in aroma improvement.

We use a modified die-rolling experiment to study whether negative externality affects a group's decisions about whether to cheat. Our results show that group members are less likely to lie when faced with a passive out-group player only if two members of the group share an unequal payment for lying. The less-paid party in the group plays a dominant role in the honest decision by proposing the true number more frequently in arguments for group coordination.

Acute fatty liver of pregnancy is a rare and critical disease in obstetrics, mainly characterized by liver failure, severe coagulopathy and other clinical manifestations, with rapid progression and high mortality. This article discusses the epidemic characteristics, pathogenesis, clinical manifestations, laboratory examination, clinical diagnosis and treatment of acute fatty liver during pregnancy. This paper summarizes the related contents of perioperative anesthesia in anesthesia methods, drug selection, coagulation regulation, organ protection and postpartum disease outcome.

Background:Cardiac arrest (CA) is one of the leading causes of death worldwide. Endoplasmic reticulum (ER) stress and ferroptosis are proven pathological mechanisms implicated in neuronal damage. Baicalein, a ferroptosis Inhibitor, improved outcomes after traumatic brain injury. We aimed to explore the effects of baicalein on brain injury viaferroptosis and ER stress in a rat model of CA.Methods:Cardiac arrest models were established in Sprague-Dawley (SD) rats. The sham group (n = 6) was untreated with inducing ventricular fibrillation to cardiac arrest and cardiopulmonary resuscitation (CPR). Survival rats were randomly divided into five groups (n = 6). Ferroptosis inhibitor and ER stress agonist were administered separately and together in three groups. There was no drug intervention in the remaining group. The neurological deficit scores were recorded. Characteristics of ferroptosis were observed. And the associated protein of ferroptosis and ER stress were determined by Western blot. Cerebral ROS production was measured by using 2′,7′-dichlorofluorescein diacetate as the oxidative fluorescent probe. Results:Baicalein treatment improved neurological outcomes and decreased neurocyte injuries compared with CPR group. The changes of ferroptosis, more specifically, iron content, glutathione peroxidase 4 (GPX4), reactive oxygen species (ROS), arachidonate 15-lipoxygenase (ALOX15) and mitochondrial characteristics, were observed in brain tissue after ROSC. ALOX15 was lower in baicalein group than in CPR group. The morphology and structure of mitochondria in baicalein group were better than in CPR group. The ER stress markers, glucose-regulated protein 78, activating Transcription Factor 4 and C/EBP homologous protein was lower in baicalein group compared with CPR group. ROS in tunicamycin group was higher than in CPR group. And ROS in baicalein +tunicamycin group was lower than in tunicamycin group. Conclusion:Ferroptosis and ER stress are both involved in brain injury after ROSC. Baicalein alleviates brain injury viasuppressing the ferroptosis and ER stress, and reduces ROS partly through inhibiting ER stress. Baicalein is a potential drug to relieve brain injury after ROSC.

In this article, the exponential synchronization of Markovian jump neural networks (MJNNs) with time-varying delays is investigated via stochastic sampling and looped-functional (LF) approach. For simplicity, it is assumed that there exist two sampling periods, which satisfies the Bernoulli distribution. To model the synchronization error system, two random variables that, respectively, describe the location of the input delays and the sampling periods are introduced. In order to reduce the conservativeness, a time-dependent looped-functional (TDLF) is designed, which takes full advantage of the available information of the sampling pattern. The Gronwall–Bellman inequalities and the discrete-time Lyapunov stability theory are utilized jointly to analyze the mean-square exponential stability of the error system. A less conservative exponential synchronization criterion is derived, based on which a mode-independent stochastic sampled-data controller (SSDC) is designed. Finally, the effectiveness of the proposed control strategy is demonstrated by a numerical example.

In this article, we study the secure control of the Markovian jumping neural networks (MJNNs) subject to deception attacks. Considering the limitation of the network bandwidth and the impact of the deception attacks, we propose two memory-based adaptive event-trigger mechanisms (AETMs). Different from the available event-trigger mechanisms, these two memory-based AETMs contain the historical triggered data not only in the triggering conditions, but also in the adaptive law. They can adjust the data transmission rate adaptively so as to alleviate the impact of deception attacks on the controlled system and to suppress the peak of the system response. In view of the proposed memory-based AETMs, a time-dependent Lyapunov functional is constructed to analyze the stability of the error system. Some sufficient conditions to ensure the asymptotical synchronization of master-slave MJNNs are obtained, and two easy-to-implement co-design algorithms for the feedback gain matrix and the trigger matrix are given. Finally, a numerical example is given to verify the feasibility and superiority of the two memory-based AETMs.

Background: Long-term care insurance (LTCI) was implemented in China to solve the elderly care problems caused by the aging population. It is crucial to evaluate the effectiveness of LTCI implementation from the perspective of value-based healthcare. Objective: This study aimed to investigate the impact of LTCI on medical care expenditure and health status in China. Methods: We used staggered difference-in-differences (DID) analysis to analyze the effect of LTCI policy on medical expenditure and health status based on China Health and Retirement Longitudinal Study data from 2011 to 2018. Results: Our findings confirmed the positive contribution of LTCI policies to medical expenditures and health status. We found that the implementation of LTCI significantly reduced inpatient and outpatient expenditure, scores of self-report of health, and CESD scores by 26.3%, 12.3%, 0.103, and 0.538, respectively. It also decreased ADL scores, but the decrease was not significant. The impact of LTCI on reducing inpatient expenditure was greater for individuals aged between 65 and 80 and those residing in urban areas and eastern cities. In terms of outpatient costs, the effect of LTCI was more pronounced among median and high-income people and people living in central and eastern cities. The impact of LTCI on self-report of health is stronger for rural populations, individuals under 80, and those in central and eastern cities. For ADL scores, LTCI affected those aged 65–80 the most. About the CESD scores, LTCI had a greater impact on rural populations, people aged 45–65, median income groups, and those in eastern cities. Conclusions: Our study underscored LTCI’s effectiveness in curbing medical expenditures and enhancing health status, offering valuable insights for future LTCI development in China and beyond. Accelerating the development of LTCI is conducive to improving the quality of life of the disabled elderly, enhancing the well-being of people’s livelihoods, and realizing the goal of value-based healthcare.

In this paper, we consider boundary extensions of two classes of mappings between metric measure spaces. These two mapping classes extend in particular the well-studied geometric mappings such as quasiregular mappings with integrable Jacobian determinant and mappings of exponentially integrable distortion with integrable Jacobian determinant. Our main results extend the corresponding results of Äkkinen and Guo (Ann. Mat. Pure. Appl. 2017) to the setting of metric measure spaces.

Germinated pigeon pea seeds (GPPSs) are good dietary supplements with satisfactory nutritional and medicinal values. In this study, UV-B treatment was used to promote the accumulation of health-promoting phenolic compounds (10 flavonoids and 1 stilbene) in GPPS. The total yield of 11 phenolic compounds (235 839.76 ± 17 118.24 ng/g DW) significantly improved (2.53-fold increase) in GPPSs exposed to UV-B radiation (3 W/m2) for 8 h, whereas free amino acid and reducing sugar contents exhibited a decreasing tendency during UV-B exposure. Meanwhile, the positive response in the antioxidant activities of enzymes and nonenzymatic extracts was noticed in UV-B-treated GPPSs. Moreover, UV-B radiation could cause tissue damages in hypocotyls and cotyledons of the GPPSs and enhance the generation of endogenous salicylic acid, thus activating the expression of biosynthesis genes (especially CHSand STS1). Overall, the simple UV-B supplementation strategy makes GPPSs more attractive as functional foods/nutraceuticals in diet for promoting human health.

Inspired by a previously reported biomimetic synthesis study, four new naturally occurring phloroglucinol trimers 1–4with unusual 6/5/5/6/6/6-fused hexacyclic ring systems, along with two known analogues (5and 6) and two known biogenetically related dimers (10and 11), were isolated from Rhodomyrtus tomentosa. Their structures and absolute configurations were unambiguously elucidated by spectroscopic analysis, X-ray diffraction, and electronic circular dichroism calculation. By mimicking two potentially alternative biosynthetic pathways, the first asymmetric syntheses of 1–4and the racemic syntheses of 5and 6were achieved in only five to six steps without the need for protecting groups. Furthermore, phloroglucinol dimers 10and 11exhibited significant in vitro antiviral activity against the respiratory syncytial virus.

ABSTRACTIn Saccharomyces cerevisiae, Atg9 is an important autophagy-related (Atg) protein, and interacts with hundreds of other proteins. How many Atg9-interacting proteins are involved in macroautophagy/autophagy is unclear. Here, we conducted a multi-omic profiling of Atg9-dependent molecular landscapes during nitrogen starvation-induced autophagy, and identified 290 and 256 genes to be markedly regulated by ATG9in transcriptional and translational levels, respectively. Unexpectedly, we found most of known Atg proteins and autophagy regulators that interact with Atg9 were not significantly changed in the mRNA or protein level during autophagy. Based on a hypothesis that proteins with similar molecular characteristics might have similar functions, we developed a new method named inference of functional interacting partners (iFIP) to integrate the transcriptomic, proteomic and interactomic data, and predicted 42 Atg9-interacting proteins to be potentially involved in autophagy, including 15 known Atg proteins or autophagy regulators. We validated 2 Atg9-interacting partners, Glo3 and Scs7, to be functional in both bulk and selective autophagy. The mRNA and protein expressions but not subcellular localizations of Glo3 and Scs7 were affected with or without ATG9during autophagy, whereas the colocalizations of the 2 proteins and Atg9 were markedly enhanced at early stages of the autophagic process. Further analyses demonstrated that Glo3 but not Scs7 regulates the retrograde transport of Atg9 during autophagy. A working model was illustrated to highlight the importance of the Atg9 interactome. Taken together, our study not only provided a powerful method for analyzing the multi-omics data, but also revealed 2 new players that regulate autophagy.Abbreviations:ALP: alkaline phosphatase; Arf1: ADP-ribosylation factor 1; Atg: autophagy-related; Co-IP: co-immunoprecipitation; Cvt: cytoplasm-to-vacuole targeting; DEM: differentially expressed mRNA; DEP: differentially expressed protein; DIC: differential interference contrast; E-ratio: enrichment ratio; ER: endoplasmic reticulum; ES: enrichment score; FC: fold change; FPKM: fragments per kilobase of exon per million fragments mapped; GAP: GTPase-activating protein; GFP: green fluorescent protein; GO: gene ontology; GSEA: gene set enrichment analysis; GST: glutathione S-transferase; HA: hemagglutinin; iFIP: inference of functional interacting partners; KO: knockout; LR: logistic regression; OE: over-expression; PAS: phagophore assembly site; PPI: protein-protein interaction; RFP: red fluorescence protein; RNA-seq: RNA sequencing; RT-PCR: real-time polymerase chain reaction; SCC: Spearman’s correlation coefficient; SD-N: synthetic minimal medium lacking nitrogen; THANATOS: The Autophagy, Necrosis, ApopTosis OrchestratorS; Vsn: variance stabilization normalization; WT: wild-type.

Enterocytozoon bieneusiis the most common microsporidian species in humans and can affect over 200 animal species. Considering possible increasing risk of human E. bieneusiinfection due to close contact with pet dogs and identification of zoonotic E. bieneusigenotypes, 589 fresh fecal specimens of pet dogs were collected from Yunnan Province, China to determine the occurrence of E. bieneusi, characterize dog-derived E. bieneusiisolates, and assess their zoonotic potential at the genotype level. Enterocytozoon bieneusiwas identified and genotyped by PCR and sequencing of the internal transcribed spacer (ITS) region of the ribosomal RNA (rRNA) gene. Twenty-nine specimens (4.9%) were positive. A statistical difference was observed in occurrence rates of E. bieneusiin pet dogs among 11 sampling sites by Fisher’s exact test. Fifteen genotypes were identified and all of them phylogenetically belonged to zoonotic group 1, including four known genotypes (EbpC, D, Peru 8, and Henan-III) and 11 novel genotypes. Genotype Henan-III was reported in dogs for the first time. The finding of known genotypes found previously in humans and novel genotypes falling into zoonotic group 1 indicates that dogs may play a role in the transmission of E. bieneusito humans in the investigated areas.

Polymer waste is a global problem. How to convert it into high value-added applications has been a challenge. Herein, we prepare a flexible all-solid-state asymmetric supercapacitor using carbon fiber composite waste resin and disposable nonwoven fabrics as starting materials. For this purpose, we prepared activated carbon (RAC) from the waste resin, and then loaded MnO2on the RAC. In parallel, we applied a silver paste to the waste nonwoven fabric. By loading RAC and MnO2-RAC separately onto the silver-coated nonwoven, they were used as the negative and positive electrodes to form an all-solid-state supercapacitor with 6.0 M KOH/PVA solid electrolyte. The devices have a specific capacitance of 148.7 F/g with an energy density of ∼52.9 Wh/kg. After 10,000 charge/discharge cycles, the devices have a capacitance retention rate of 83.9 %, indicating excellent cycle life. They also have excellent flexibility, maintaining the high capacitance almost unchanged under various bending conditions.

Wild edible mushrooms are important as a source of nutraceuticals and for the discovery of bioactive metabolites as pharmaceuticals. In this work, 10 rare 2,5-diarylcyclopentenone derivatives were isolated from the wild edible mushroom Paxillus involutus(Batsch) Fr., including eight novel compounds termed involutenone A–H (1–8) and two previously identified compounds (9–10). Their structures were established using high-resolution electrospray ionization mass spectroscopy and 1D and 2D nuclear magnetic resonance data. The absolute configurations of compounds 1–3and 6–8were assigned based on the comparison of the experimental and calculated electronic circular dichroism data. The antioxidant activities of 1–8were tested through DPPH free radical scavenging, hydroxyl radical scavenging, and superoxide anion radical scavenging assays. Compounds 3, 5, 6, and 7demonstrated significant antioxidant activity compared to the positive control (tert-butylhydroquinone). These compounds could be effective natural antioxidants with considerable pharmaceutical value.

Hematological malignancies are a class of malignant neoplasms attributed to abnormal differentiation of hematopoietic stem cells (HSCs). The systemic involvement, poor prognosis, chemotherapy resistance, and recurrence common in hematological malignancies urge researchers to look for novel treatment targets and mechanisms. In recent years, epigenetic abnormalities have been shown to play a vital role in tumorigenesis and progression in hematological malignancies. In addition to DNA methylation and histone modifications, which are most studied, RNA methylation has become increasingly significant. In this review, we elaborate recent advances in the understanding of RNA modification in the pathogenesis, diagnosis and molecular targeted therapies of hematological malignancies and discuss its intricate interactions with other epigenetic modifications, including DNA methylation, histone modifications and noncoding RNAs.

C19H22O7, orthorhombic, P21(no. 4), a= 6.4154(1) Å, b= 7.8782(2) Å, c= 17.1555(4) Å, β= 91.021(2)°, V= 866.93(3) Å3, Z= 2, Rgt(F) = 0.0326, wRref(F2) = 0.1028, T = 150 K.

Eight new germacranolides, minusolides A–H (1–8), along with two known analogues, 9and 10, were isolated from the whole plant of Carpesium minus. Their structures were elucidated by spectroscopic analysis. Compounds 1and 2, and 6and 9are two pairs of rare epimers with opposite configurations at C-2 of the 2-methylbutyryloxy group. The absolute configurations were determined by X-ray diffraction studies. Compound 7exhibited cytotoxic activities against MDA-MB-231, A549, and HCT-116 cells with IC50values of 6.1 ± 0.2, 8.4 ± 0.6, and 3.7 ± 0.6 μM, respectively. Compound 7induced the apoptosis of HCT-116 cells via suppression of PARP and promoting cleavage of PARP.

Pegaharines A–G (1–6), six novel β-carboline alkaloids representing three types of skeleton, were isolated from the seeds of Peganum harmala. Compound 1is a peculiar β-carboline alkaloid characterized by the unprecedented carbon skeleton of an azepine–indole system. Compounds 3–6represent the first examples of heterodimers constructed from rare tetracyclic β-carboline and classic tricyclic β-carboline alkaloids. Compounds 1and 2were characterized by X-ray crystallography. Compound 4exhibited strong antiviral activity against HSV-2, with an IC50value of 2.12 ± 0.14 μM.