B-O-O-B Impurity Induces Ultralong Room-Temperature Phosphorescence of Boric Acid.

Organic materials that can emit ultralong room-temperature phosphorescence (RTP) have attracted a great deal of interest. Whether the pure boric acid (BA) solid can emit RTP and the origin of the RTP in BA caused a debate recently. Herein, our first-principles calculations and experimental measurements suggest that RTP of BA originates from the B-O-O-B group in a (H2BO3)2 species, which can be formed by polymerization of two dehydrogenated BA molecules under light irradiation. The calculated absorption, fluorescence, and phosphorescence spectra of B-O-O-B match well with the experiments. Experimental X-ray photoelectron and X-ray absorption spectra evidence the existence of B-O-O-B in BA. The O-O bond in B-O-O-B can break upon optical excitation, creating two B-O radicals. Radiative transition from localized dangling orbitals of the B-O radicals to the delocalized orbitals of the crystal bulk leads to the observed RTP. Our calculated phosphorescence lifetime is ∼1 s, which agrees well with the experiment.

Telomere-to-telomere reference genome for Panax ginseng highlights the evolution of saponin biosynthesis.

Ginseng (Panax ginseng) is a representative of Chinese traditional medicine, also used worldwide, while the triterpene saponin ginsenoside is the most important effective compound within it. Ginseng is an allotetraploid, with complex genetic background, making the study of its metabolic evolution challenging. In this study, we assembled a telomere-to-telomere ginseng reference genome, constructed of 3.45 Gb with 24 chromosomes and 77 266 protein-coding genes. Additionally, the reference genome was divided into two subgenomes, designated as subgenome A and B. Subgenome A contains a larger number of genes, whereas subgenome B has a general expression advantage, suggesting that ginseng subgenomes experienced asymmetric gene loss with biased gene expression. The two subgenomes separated approximately 6.07 million years ago, and subgenome B shows the closest relation to Panax vietnamensis var. fuscidiscus. Comparative genomics revealed an expansion of gene families associated with ginsenoside biosynthesis in both ginseng subgenomes. Furthermore, both tandem duplications and proximal duplications play crucial roles in ginsenoside biosynthesis. We also screened functional genes identified in previous research and found that some of these genes located in colinear regions between subgenomes have divergence functions, revealing an unbalanced evolution in both subgenomes and the saponin biosynthesis pathway in ginseng. Our work provides important resources for future genetic studies and breeding programs of ginseng, as well as the biosynthesis of ginsenosides.

The predominant Quillaja Saponaria fraction, QS-18, is safe and effective when formulated in a liposomal murine cancer peptide vaccine.

Extracts of the Chilean soapbark tree, Quillaja Saponaria (QS) are the source of potent immune-stimulatory saponin compounds. This study compared the adjuvanticity and toxicity of QS-18 and QS-21, assessing the potential to substitute QS-18 in place of QS-21 for vaccine development. QS-18, the most abundant QS saponin fraction, has been largely overlooked due to safety concerns. We found that QS-18 spontaneously inserted into liposomes, thereby neutralizing hemolytic activity, and following administration did not induce local reactogenicity in a footpad swelling test in mice. With high-dose intramuscular administration, transient weight loss was minor, and QS-18 did not induce significantly more weight loss compared to a liposome vaccine adjuvant system lacking it. Two days after administration, no elevation of inflammatory cytokines was detected in murine serum. In a formulation including cobalt-porphyrin-phospholipid (CoPoP) for short peptide sequestration, QS-18 did not impact the formation of peptide nanoparticles. With immunization, QS-18 peptide particles induced higher levels of cancer neoepitope-specific and tumor-associated antigen-specific CD8+ T cells compared to QS-21 particles, without indication of greater toxicity based on mouse body weight. T cell receptor sequencing of antigen-specific CD8+ T cells showed that QS-18 induced significantly more T cell transcripts. In two murine cancer models, vaccination with QS-18 peptide particles induced a similar therapeutic effect as QS-21 particles, without indication of increased toxicity. Antigen-specific CD8+ T cells in the tumor microenvironment were found to express the exhaustion marker PD-1, pointing to the rationale for exploring combination therapy. Taken together, these data demonstrate that QS-18, when formulated in liposomes, can be a safe and effective adjuvant to induce tumor-inhibiting cellular responses in murine models with potential to facilitate or diminish costs of production for vaccine adjuvant systems. Further studies are warranted to assess liposomal QS-18 immunogic, reactogenic and toxicological profiles in mice and other animal species.

Identification of Enhanced Vaccine Mimotopes for the p15E Murine Cancer Antigen.

Mimotopes of short CD8+ T-cell epitopes generally comprise one or more mutated residues, and can increase the immunogenicity and function of peptide cancer vaccines. We recently developed a two-step approach to generate enhanced mimotopes using positional peptide microlibraries and herein applied this strategy to the broadly used H-2Kb-restricted murine leukemia p15E tumor rejection epitope. The wild-type p15E epitope (sequence: KSPWFTTL) was poorly immunogenic in mice, even when combined with a potent peptide nanoparticle vaccine system and did not delay p15E-expressing MC38 tumor growth. Following positional microlibrary functional screening of over 150 mimotope candidates, two were identified, both with mutations at residue 3 (p15E-P3C; "3C," and p15E-P3M; "3M") that better induced p15E-specific CD8+ T cells and led to tumor rejection. Although 3M was more immunogenic, 3C effectively delayed tumor growth in a therapeutic setting relative to the wild-type p15E. As 3C had less H-2Kb affinity relative to both p15E and 3M, 15 additional mimotope candidates (all that incorporated the 3C mutation) were assessed that maintained or improved predicted MHC-I affinity. Valine substitution at position 2 (3C2V, sequence: KVCWFTTL) led to improved p15E-specific immunogenicity, tumor rejection, and subsequent long-term antitumor immunity. 3C, 3M, and 3C2V mimotopes were more effective than p15E in controlling MC38 and B16-F10 tumors. T-cell receptor (TCR) sequencing revealed unique TCR transcripts for mimotopes, but there were no major differences in clonality. These results provide new p15E mimotopes for further vaccine use and illustrate considerations for MHC-I affinity, immunogenicity, and functional efficacy in mimotope design. SIGNIFICANCE: The MHC-I-restricted p15E tumor rejection epitope is expressed in multiple murine cancer lines and is used as a marker of antitumor cellular immunity, but has seen limited success as a vaccine immunogen. An in vivo screening approach based on a positional peptide microlibraries is used to identify enhanced p15E mimotopes bearing amino acid mutations that induce significantly improved functional immunogenicity relative to vaccination with the wild-type epitope.

Adjuvanted nanoliposomes displaying six hemagglutinins and neuraminidases as an influenza virus vaccine.

Inclusion of defined quantities of the two major surface proteins of influenza virus, hemagglutinin (HA) and neuraminidase (NA), could benefit seasonal influenza vaccines. Recombinant HA and NA multimeric proteins derived from three influenza serotypes, H1N1, H3N2, and type B, are surface displayed on nanoliposomes co-loaded with immunostimulatory adjuvants, generating "hexaplex" particles that are used to immunize mice. Protective immune responses to hexaplex liposomes involve functional antibody elicitation against each included antigen, comparable to vaccination with monovalent antigen particles. When compared to contemporary recombinant or adjuvanted influenza virus vaccines, hexaplex liposomes perform favorably in many areas, including antibody production, T cell activation, protection from lethal virus challenge, and protection following passive sera transfer. Based on these results, hexaplex liposomes warrant further investigation as an adjuvanted recombinant influenza vaccine formulation.

Isotope Effect-Enabled Crystal Enlargement in Metal-Organic Frameworks.

Synthesizing large metal-organic framework (MOF) single crystals has garnered significant research interest, although it is hindered by the fast nucleation kinetics that gives rise to numerous small nuclei. Given the different chemical origins inherent in various types of MOFs, the development of a general approach to enhancing their crystal sizes presents a formidable challenge. Here, we propose a simple isotopic substitution strategy to promote size growth in MOFs by inhibiting nucleation, resulting in a substantial increase in the crystal volume ranging from 1.7- to 165-fold. Impressively, the crystals prepared under optimized conditions by normal approaches can be further enlarged by the isotope effect, yielding the largest MOF single crystal (2.9 cm × 0.48 cm × 0.23 cm) among the one-pot synthesis method. Detailed in situ characterizations reveal that the isotope effect can retard crystallization kinetics, establish a higher nucleation energy barrier, and consequently generate fewer nuclei that eventually grow larger. Compared with the smaller crystals, the isotope effect-enlarged crystal shows 33% improvement in the X-ray dose rate detection limit. This work enriches the understanding of the isotope effect on regulating the crystallization process and provides inspiration for exploring potential applications of large MOF single crystals.

SARS-CoV-2 Protein Nanoparticle Vaccines Formed In Situ From Lyophilized Lipids.

The receptor binding domain (RBD) of the SARS-CoV-2 Spike (S) glycoprotein is an appealing immunogen, but associated vaccine approaches must overcome the hapten-like nature of the compact protein and adapt to emerging variants with evolving RBD sequences. Here, a vaccine manufacturing methodology is proposed comprising a sterile-filtered freeze-dried lipid cake formulation that can be reconstituted with liquid proteins to instantaneously form liposome-displayed protein nanoparticles. Mannitol is used as a bulking agent and a small amount of Tween-80 surfactant is required to achieve reconstituted submicron particles that do not precipitate prior to usage. The lipid particles include an E. coli-derived monophosphoryl lipid A (EcML) for immunogenicity, and cobalt porphyrin-phospholipid (CoPoP) for antigen display. Reconstitution of the lipid cake with aqueous protein results in rapid conversion of the RBD into intact liposome-bound format prior to injection. Protein particles can readily be formed with sequent-divergent RBD proteins derived from the ancestral or Omicron strains. Immunization of mice elicits antibodies that neutralize respective viral strains. When K18-hACE2 transgenic mice are immunized and challenged with ancestral SARS-CoV-2 or the Omicron BA.5 variant, both liquid liposomes displaying the RBD and rapid reconstituted particles protect mice from infection, as measured by the viral load in the lungs and nasal turbinates.

Plant Protein-Derived Active Peptides: A Comprehensive Review.

Active peptides are a class of physiologically active protein fragments, which can be prepared from different sources. In the past few decades, the production of peptides with various effects from different plant proteins continues to receive academic attention. With advances in extraction, purification, and characterization techniques, plant protein-derived active peptides continue to be discovered. They have been proven to have various functional activities such as antioxidant, antihypertensive, immunomodulatory, antimicrobial, anti-inflammatory, antidiabetic, antithrombotic, and so on. In this review, we searched Web of Science and China National Knowledge Infrastructure for relevant articles published in recent years. There are 184 articles included in this manuscript. The current status of plant protein-derived active peptides is systematically introduced, including their sources, preparation, purification and identification methods, physiological activities, and applications in the food industry. Special emphasis has been placed on the problems of active peptide exploration and the future trend. Based on these, it is expected to provide theoretical reference for the further exploitation of plant protein-derived active peptides, and promote the healthy and rapid development of active peptide industry.

ACSL4-Mediated Ferroptosis and Its Potential Role in Central Nervous System Diseases and Injuries.

As an iron-dependent regulated form of cell death, ferroptosis is characterized by iron-dependent lipid peroxidation and has been implicated in the occurrence and development of various diseases, including nervous system diseases and injuries. Ferroptosis has become a potential target for intervention in these diseases or injuries in relevant preclinical models. As a member of the Acyl-CoA synthetase long-chain family (ACSLs) that can convert saturated and unsaturated fatty acids, Acyl-CoA synthetase long-chain familymember4 (ACSL4) is involved in the regulation of arachidonic acid and eicosapentaenoic acid, thus leading to ferroptosis. The underlying molecular mechanisms of ACSL4-mediated ferroptosis will promote additional treatment strategies for these diseases or injury conditions. Our review article provides a current view of ACSL4-mediated ferroptosis, mainly including the structure and function of ACSL4, as well as the role of ACSL4 in ferroptosis. We also summarize the latest research progress of ACSL4-mediated ferroptosis in central nervous system injuries and diseases, further proving that ACSL4-medicated ferroptosis is an important target for intervention in these diseases or injuries.

Buried penis: a histological and histochemical study of dartos fascia.

This study aimed to determine whether the abnormal deep layer of dartos fascia plays an important role in buried penis. Forty-nine patients with buried penis were treated with anatomical resection of the deep layer of dartos fascia under a microscope. Penile length was measured before and after completely resecting the deep layer to investigate the role of this layer in penile retraction. The superficial and deep layers of dartos fascia were collected from 49 patients with buried penis, the normal superficial layers were collected from 25 children/adults who underwent circumcision for nonmedical reasons, and the normal deep layers were collected from 20 adult cadavers. The penile fascia samples were stained with hematoxylin-eosin, Masson's trichrome, Sirius red, and Verhoeff's Van Gieson, and subjected to immunohistochemical examination and scanning electron microscopy. The penile shaft (mean ± standard deviation) was found to be significantly elongated after resecting the deep layer compared with that before resection (6.8 ± 1.9 cm vs 6.0 ± 1.6 cm, P < 0.001). An abnormal deep layer of dartos fascia characterized by disordered and fragmented elastic fibers was observed in 87.8% (43/49) of buried penis samples, whereas no abnormal deep layer was observed in normal penises from cadavers (0/20, P < 0.001). Thus, the abnormal deep layer of dartos fascia plays an important role in the buried penis. Its resection is helpful for avoiding recurrence.

The investigation on the hypercoagulability of hepatocellular carcinoma-related cerebral infarction with thromboelastography.

AIM: To investigate the hypercoagulability of hepatocellular carcinoma (HCC)-related cerebral infarction (HCRCI) with thromboelastography (TEG). METHODS: A multicenter prospective study was conducted in HCRCI patients, HCC patients without cerebral infarction, and acute cerebral infarction (ACI) patients without HCC between January 2016 and December 2019. TEG parameters and laboratory and clinical data were collected and compared among the three groups. To confirm the independent risk factors of HCRCI, multivariate analyses were conducted. Receiver operating characteristic (ROC) curves were utilized to evaluate the area under the curve (AUC) plotted by each independent risk factor. RESULTS: There were 38 patients recruited in the HCRCI group, and 152 patients were recruited to the HCC group and the ACI group. The levels of plasma neutrophil count, D-dimer, α-fetoprotein (AFP), carcinoembryonic antigen, and maximum amplitude (MA)-a parameter of TEG-were significantly higher in the HCRCI group than HCC and ACI groups. Multivariate logistic regression analysis showed that increased neutrophile count, D-dimer, AFP, and MA were independently associated with HCRCI. ROC curve analysis showed first that AUC of MA for HCRCI was .875, which was larger than the other risk factors, and second that the optimal cutoff value for MA was 61.35, with a sensitivity of 89.50% and specificity of 66.40%. CONCLUSION: It was suggested that TEG disclosed that the pathogenesis of HCRIC is exactly related to the hypercoagulability. And with a cutoff value of MA equaling to 61.35, TEG facilitates clinicians to identify HCC patients at high risk of HCRIC.

TrkB agonist N-acetyl serotonin promotes functional recovery after traumatic brain injury by suppressing ferroptosis via the PI3K/Akt/Nrf2/Ferritin H pathway.

Ferroptosis is a form of regulated cell death that is mainly triggered by iron-dependent lipid peroxidation. A growing body of evidence suggests that ferroptosis is involved in the pathophysiology of traumatic brain injury (TBI), and tropomyosin-related kinase B (TrkB) deficiency would mediate TBI pathologies. As an agonist of TrkB and an immediate precursor of melatonin, N-acetyl serotonin (NAS) exerts several beneficial effects on TBI, but there is no information regarding the role of NAS in ferroptosis after TBI. Here, we examined the effect of NAS treatment on TBI-induced functional outcomes and ferroptosis. Remarkably, the administration of NAS alleviated TBI-induced neurobehavioral deficits, lesion volume, and neurodegeneration. NAS also rescued TBI-induced mitochondrial shrinkage, the changes in ferroptosis-related molecule expression, and iron accumulation in the ipsilateral cortex. Similar results were obtained with a well-established ferroptosis inhibitor, liproxstatin-1. Furthermore, NAS activated the TrkB/PI3K/Akt/Nrf2 pathway in the mouse model of TBI, while inhibition of PI3K and Nrf2 weakened the protection of NAS against ferroptosis both in vitro and in vivo, suggesting that a possible pathway linking NAS to the action of anti-ferroptosis was TrkB/PI3K/Akt/Nrf2. Given that ferritin H (Fth) is a known transcription target of Nrf2, we then investigated the effects of NAS on neuron-specific Fth knockout (Fth-KO) mice. Strikingly, Fth deletion almost abolished the protective effects of NAS against TBI-induced ferroptosis and synaptic damage, although Fth deletion-induced susceptibility toward ferroptosis after TBI was reversed by an iron chelator, deferoxamine. Taken together, these data indicate that the TrkB agonist NAS treatment appears to improve brain function after TBI by suppressing ferroptosis, at least in part, through activation of the PI3K/Akt/Nrf2/Fth pathway, providing evidence that NAS is likely to be a promising anti-ferroptosis agent for further treatment for TBI.

Targeting Molecular Mediators of Ferroptosis and Oxidative Stress for Neurological Disorders.

With the acceleration of population aging, nervous system diseases including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), anxiety, depression, stroke, and traumatic brain injury (TBI) have become a huge burden on families and society. The mechanism of neurological disorders is complex, which also lacks effective treatment, so relevant research is required to solve these problems urgently. Given that oxidative stress-induced lipid peroxidation eventually leads to ferroptosis, both oxidative stress and ferroptosis are important mechanisms causing neurological disorders, targeting mediators of oxidative stress and ferroptosis have become a hot research direction at present. Our review provides a current view of the mechanisms underlying ferroptosis and oxidative stress participate in neurological disorders, the potential application of molecular mediators targeting ferroptosis and oxidative stress in neurological disorders. The target of molecular mediators or agents of oxidative stress and ferroptosis associated with neurological disorders, such as reactive oxygen species (ROS), nuclear factor erythroid 2-related factor-antioxidant response element (Nrf2-ARE), n-acetylcysteine (NAC), Fe2+, NADPH, and its oxidases NOX, has been described in this article. Given that oxidative stress-induced ferroptosis plays a pivotal role in neurological disorders, further research on the mechanisms of ferroptosis caused by oxidative stress will help provide new targets for the treatment of neurological disorders.

Weighted Gene Co-Expression Network Analysis to Identify Potential Biological Processes and Key Genes in COVID-19-Related Stroke.

The purpose of this research was to explore the underlying biological processes causing coronavirus disease 2019- (COVID-19-) related stroke. The Gene Expression Omnibus (GEO) database was utilized to obtain four COVID-19 datasets and two stroke datasets. Thereafter, we identified key modules via weighted gene co-expression network analysis, following which COVID-19- and stroke-related crucial modules were crossed to identify the common genes of COVID-19-related stroke. The common genes were intersected with the stroke-related hub genes screened via Cytoscape software to discover the critical genes associated with COVID-19-related stroke. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis for common genes associated with COVID-19-related stroke, and the Reactome database was used to annotate and visualize the pathways involved in the key genes. Two COVID-19-related crucial modules and one stroke-related crucial module were identified. Subsequently, the top five genes were screened as hub genes after visualizing the genes of stroke-related critical module using Cytoscape. By intersecting the COVID-19- and stroke-related crucial modules, 28 common genes for COVID-19-related stroke were identified. ITGA2B and ITGB3 have been further identified as crucial genes of COVID-19-related stroke. Functional enrichment analysis indicated that both ITGA2B and ITGB3 were involved in integrin signaling and the response to elevated platelet cytosolic Ca2+, thus regulating platelet activation, extracellular matrix- (ECM-) receptor interaction, the PI3K-Akt signaling pathway, and hematopoietic cell lineage. Therefore, platelet activation, ECM-receptor interaction, PI3K-Akt signaling pathway, and hematopoietic cell lineage may represent the potential biological processes associated with COVID-19-related stroke, and ITGA2B and ITGB3 may be potential intervention targets for COVID-19-related stroke.

Multi-omics analysis reveals the influence of tetracycline on the growth of ryegrass root.

Environmental factors, including antibiotics such as tetracycline, can alter biological processes in plants. To ascertain how cell/tissue response to tetracycline, a multi-omic analysis was implemented to explore the molecular mechanism of tetracycline influencing the growth of ryegrass root. Tetracycline induced extensive changes in the root metabolome in plants, particularly impacting metabolites of flavonoid metabolic pathways, which were supported through consistent differences between transcriptome and proteome. Cross-comparison between mRNA and protein contents considered the authentication of congruence with related metabolites and revealed changes of several biological processes under tetracycline stress. Overall, we present an undemanding multi-omic strategy to survey the significant influence on the root under tetracycline stress.

A biodegradable Fe/Zn-3Cu composite with requisite properties for orthopedic applications.

Zinc (Zn)-based metals and alloys are emerging as promising biodegradable implant materials due to their inherent biodegradability and good biocompatibility. However, this class of materials exhibits low mechanical strength and a slow degradation rate, which hinders their clinical application. Here we report the development of a new biodegradable Fe/Zn-3Cu composite fabricated by infiltration casting of a Zn-3Cu alloy into an Fe foam followed by hot-rolling. Our results indicate that the hot-rolled (HR) Fe/Zn-3Cu composite exhibited an α-Zn matrix phase, a secondary CuZn5 phase, and an α-Fe phase. The HR Fe/Zn-3Cu composite exhibited an ultimate tensile strength of 269 MPa, a tensile yield strength of 210 MPa, and an elongation of 27%. The HR Fe/Zn-3Cu composite showed a degradation rate of 228 µm/year after immersion in Hanks' solution for 30 d The diluted extract of the HR Fe/Zn-3Cu composite exhibited a higher cell viability than that of the HR Zn-3Cu alloy in relation to MC3T3-E1 and MG-63 cells. Furthermore, the HR Fe/Zn-3Cu composite showed significantly better antibacterial ability than that of the HR Zn-3Cu alloy in relation to S. aureus. Overall, the HR Fe/Zn-3Cu composite can be anticipated to be a promising biodegradable implant material for bone-fixation applications. STATEMENT OF SIGNIFICANCE: This work reports a new biodegradable Fe/Zn-3Cu composite fabricated by infiltration casting and followed by hot-rolling for biodegradable bone-fixation application. Our findings demonstrated that the hot-rolled (HR) Fe/Zn-3Cu composite exhibited an ultimate tensile strength of 269.1 MPa, a tensile yield strength of 210.3 MPa, and an elongation of 26.7%. HR Fe/Zn-3Cu composite showed a degradation rate of 227.6 µm/a, higher than HR Zn-3Cu alloy after immersion in Hanks' solution for 30 d The diluted extracts of the HR Fe/Zn-3Cu composite exhibited a higher cell viability than HR Zn-3Cu alloy toward MC3T3-E1 cells. Furthermore, the HR Fe/Zn-3Cu composite showed significantly better antibacterial ability than the HR Zn-3Cu alloy toward S. aureus.

Ferristatin II, an Iron Uptake Inhibitor, Exerts Neuroprotection against Traumatic Brain Injury via Suppressing Ferroptosis.

As a specific ferroptosis marker, transferrin receptor 1 (TfR1) expression is increased following traumatic brain injury (TBI), but the precise role of TfR1 in TBI-induced ferroptosis and neurodegeneration remains to be determined. To further identify more potent ferroptosis inhibitors and effective targets for treating TBI, our study aims at investigating the effects of TfR1 on ferroptosis in a mouse TBI model using ferristatin II (an iron uptake and TfR1 inhibitor). The effect of ferristatin II was first verified in the HT-22 cell line in vitro and showed antiferroptotic action when exposed to ferric citrate (FAC), which is in parallel with the results obtained from the positive controls, including deferoxamine (DFO) and liproxstatin-1 (Lip-1). In vivo, ferristatin II administration reduced the expression of TfR1 at 12 h after TBI, and immunofluorescence experiments further confirmed that this decreased TfR1-positive cells were neurons. Importantly, ferristatin II suppressed TBI-induced iron homeostatic imbalance by decreasing the content of Fe (III) and iron-positive deposits and reversed the expression of iron homeostasis-related proteins. Moreover, ferristatin II attenuated TBI-induced lipid peroxidation by reversing the expression of lipid peroxidative genes and proteins, as well as the increase in malondialdehyde (MDA) level following TBI. Finally, ferristatin II alleviated TBI-induced neuronal injury and neurodegeneration, as detected by staining with Nissl and Fluoro-Jade B, thereby exerting a neuroprotective effect. In summary, these data indicated that ferristatin II might be a potential strategy to restrain ferroptosis and develop novel therapeutic agents against TBI.

Cancer Related Subarachnoid Hemorrhage: A Multicenter Retrospective Study Using Propensity Score Matching Analysis.

OBJECTIVE: To investigate the clinical features, risk factors and underlying pathogenesis of cancer related subarachnoid hemorrhage (SAH). METHODS: Clinical data of SAH in patients with active cancer from January 2010 to December 2020 at four centers were retrospectively reviewed. Patients with active cancer without SAH were matched to SAH patients with active cancer group. Logistic regression was applied to investigate the independent risk factors of SAH in patients with active cancer, after a 1:1 propensity score matching (PSM). A receiver operator characteristic curve was configured to calculate the optimal cut-off value of the joint predictive factor for cancer related SAH. RESULTS: A total of 82 SAH patients with active cancer and 309 patients with active cancer alone were included. Most SAH patients with cancer had poor outcomes, with 30-day mortality of 41.5%, and with 90-day mortality of 52.0%. The PSM yielded 75 pairs of study participants. Logistic regression revealed that a decrease in platelet and prolonged prothrombin time were the independent risk factors of cancer related SAH. In addition, receiver operator characteristic curve of the joint predictive factor showed the largest AUC of 0.8131, with cut-off value equaling to 11.719, with a sensitivity of 65.3% and specificity of 89.3%. CONCLUSION: Patients with cancer related SAH often have poor outcomes. The decrease in platelet and prolonged prothrombin time are the independent risk factors of cancer related SAH, and the joint predictive factor with cutoff value equal to 11.719 should hence serve as a novel biomarker of cancer related SAH.

Inhibition of lncRNA NEAT1 protects endothelial cells against hypoxia/reoxygenation­induced NLRP3 inflammasome activation by targeting the miR­204/BRCC3 axis.

Cardiovascular ischemia/reperfusion (I/R) injury is primarily caused by oxygen recovery after prolonged hypoxia. Previous studies found that the long non coding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1) was involved in cardiovascular pathology, and that NOD­like receptor protein 3 (NLRP3) inflammasome activation­dependent pyroptosis played a key role in cardiovascular I/R injury. The present study aimed to explore the molecular mechanism of I/R pathogenesis in order to provide novel insights for potential future therapies. Cell viability and lactate dehydrogenase enzyme activity assays were used to detect cell injury after human umbilical vein endothelial cells (HUVECs) were subjected to hypoxia/reoxygenation (H/R). The expression of the NEAT1/microRNA (miR)­204/BRCA1/BRCA2­containing complex subunit 3 (BRCC3) axis was examined by reverse transcription­quantitative PCR, and the associations among genes were confirmed by luciferase reporter assays. Western blotting and ELISA were used to measure the level of NLRP3 inflammasome activation­dependent pyroptosis. The results demonstrated that NEAT1, BRCC3 expression and NLRP3 inflammasome activation­dependent pyroptosis were significantly increased in H/R­injured HUVECs, whereas silencing BRCC3 or NEAT1 attenuated H/R­induced injury and pyroptosis. NEAT1 positively regulated BRCC3 expression via competitively binding with miR­204. Moreover, NEAT1 overexpression counteracted miR­204 mimic­induced injury, BRCC3 expression and NLRP3 inflammasome activation­dependent pyroptosis. Taken together, these findings demonstrated that inhibition of lncRNA NEAT1 protects HUVECs against H/R­induced NLRP3 inflammasome activation by targeting the miR­204/BRCC3 axis.

Ferroptosis Mediated by Lipid Reactive Oxygen Species: A Possible Causal Link of Neuroinflammation to Neurological Disorders.

Increasing evidence indicates a possible causal link between neuroinflammation and neurological disorders, including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), and stroke. A putative mechanism underlying such a link can be explained by ferroptosis. Current studies have shown that disturbances of iron homeostasis, glutamate excitatory toxicity, lipid reactive oxygen species (ROS), and other manifestations related to ferroptosis can be detected in several neurological disorders caused by neuroinflammation. To date, compelling evidence indicates that damage-associated molecular pattern (DAMP) molecules (e.g., ROS) produced in the process of ferroptosis activate glial cells by activating neuroimmune pathways and then produce a series of inflammatory factors which contribute to neurological disorders. Our review article provides a current view of the involvement of ferroptosis or ROS in the pathological process of neuroinflammation, the effects of neuroinflammation mediated by ferroptosis in neurological disorders, a better understanding of the mechanisms underlying ferroptosis participates in neuroinflammation, and the potential treatments for neurological disorders. In addition, further research on the mechanisms of ferroptosis as well as the link between ferroptosis and neuroinflammation will help provide new targets for treatment.