Collective chiroptical activity through the interplay of excitonic and charge-transfer effects in localized plasmonic fields.

The collective light-matter interaction of chiral supramolecular aggregates or molecular ensembles with confined light fields remains a mystery beyond the current theoretical description. Here, we programmably and accurately build models of chiral plasmonic complexes, aiming to uncover the entangled effects of excitonic correlations, intra- and intermolecular charge transfer, and localized surface plasmon resonances. The intricate interplay of multiple chirality origins has proven to be strongly dependent on the site-specificity of chiral molecules on plasmonic nanoparticle surfaces spanning the nanometer to sub-nanometer scale. This dependence is manifested as a distinct circular dichroism response that varies in spectral asymmetry/splitting, signal intensity, and internal ratio of intensity. The inhomogeneity of the surface-localized plasmonic field is revealed to affect excitonic and charge-transfer mixed intermolecular couplings, which are inherent to chirality generation and amplification. Our findings contribute to the development of hybrid classical-quantum theoretical frameworks and the harnessing of spin-charge transport for emergent applications.

A General Molecular Structural Design for Highly Efficient Photopyroptosis that can be Activated within 10 s Irradiation.

Photopyroptosis is an emerging research branch of photodynamic therapy (PDT), whereas there remains a lack of molecular structural principles to fabricate photosensitizers for triggering a highly efficient pyroptosis. Herein, a general and rational structural design principle to implement this hypothesis, is proposed. The principle relies on the clamping of cationic moieties (e.g., pyridinium, imidazolium) onto one photosensitive core to facilitate a considerable mitochondrial targeting (both of the inner and the outer membranes) of the molecules, thus maximizing the photogenerated reactive oxygen species (ROS) at the specific site to trigger the gasdermin E-mediated pyroptosis. Through this design, the pyroptotic trigger can be achieved in a minimum of 10 s of irradiation with a substantially low light dosage (0.4 J cm⁻2), compared to relevant work reported (up to 60 J cm⁻2). Moreover, immunotherapy with high tumor inhibition efficiency is realized by applying the synthetic molecules alone. This structural paradigm is valuable for deepening the understanding of PDT (especially the mitochondrial-targeted PDT) from the perspective of pyroptosis, toward the future development of the state-of-the-art form of PDT.

Edible Long-Afterglow Photoluminescent Materials for Bioimaging.

Confining luminophores into modified hydrophilic matrices or polymers is a straightforward and widely used approach for afterglow bioimaging. However, the afterglow quantum yield and lifetime of the related material remain unsatisfactory, severely limiting the using effect especially for deep-tissue time-resolved imaging. This fact largely stems from the dilemma between material biocompatibility and the quenching effect of water environment. Herein an in situ metathesis promoted doping strategy is presented, namely, mixing ≈10-3 weight ratio of organic-emitter multicarboxylates with inorganic salt reactants, followed by metathesis reactions to prepare a series of hydrophilic but water-insoluble organic-inorganic doping afterglow materials. This strategy leads to the formation of edible long-afterglow photoluminescent materials with superior biocompatibility and excellent bioimaging effect. The phosphorescence quantum yield of the materials can reach dozens of percent (the highest case: 66.24%), together with the photoluminescent lifetime lasting for coupes of seconds. Specifically, a long-afterglow barium meal formed by coronene salt emitter and BaSO4 matrix is applied into animal experiments by gavage, and bright stomach afterglow imaging is observed by instruments or mobile phone after ceasing the photoexcitation with deep tissue penetration. This strategy allows a flexible dosage of the materials during bioimaging, facilitating the development of real-time probing and theranostic technology.

[Changes in fingerprint and chromaticity values of Mori Cortex during stir-frying process].

This study aims to reveal the dynamics of the HPLC fingerprint, chromaticity values, and main chemical components of Mori Cortex during the stir-frying process. The fingerprints of raw and processed products of Mori Cortex were established. The content of mulberroside A, oxyresveratrol, kuwanon G, and kuwanon H in the samples and the chromaticity values of the samples were determined. Furthermore, the similarity evaluation of fingerprints and the correlation analysis between fingerprints and chromaticity values were carried out. The results showed that the fingerprints of raw and processed products of Mori Cortex had high similarity, and the overall changes in the content of the main chemical components in the stir-frying process were similar. According to the experience, when the stir-frying is moderate, the total chromaticity value difference |ΔE~*_(ab)| is above 1.5. With the extension of stir-frying time, the L~* and E~*_(ab) values keep decreasing, and the a~* value keeps increasing. The results of the correlation analysis between fingerprints and chromaticity values showed that peaks 1(5-hydroxy maltol), 2(mulberroside A), 3, 4, 6, 7, 11(oxyresveratrol), 14, 17(kuwanon G), and 18(kuwanon H) had significant correlations with the chromaticity values. Quantitative analysis of the four components with higher content showed that the content of the four components decreased to varying degrees when the stir-frying was excessive. In addition, 5-hydroxy maltol was produced after stir-frying of Mori Cortex, and the fingerprint and chromaticity values showed regular changes during the stir-frying process. The chromaticity can be included in the evaluation of the stir-frying process of Mori Cortex, which provides a reference for standardizing the quality of stir-fried Mori Cortex.

Gel microspheres enhance the stemness of ADSCs by regulating cell-ECM interaction.

The gel microsphere culture system (GMCS) showed various advantages for mesenchymal stem cell (MSC) expansion and delivery, such as high specific surface area, small and regular shape, extensive adjustability, and biomimetic properties. Although various technologies and materials have been developed to promote the development of gel microspheres, the differences in the biological status of MSCs between the GMCS and the traditional Petri dish culture system (PDCS) are still unknown, hindering gel microspheres from becoming a culture system as widely used as petri dishes. In the previous study, an excellent "all-in-one" GMCS has been established for the expansion of human adipose-derived MSCs (hADSCs), which showed convenient cell culture operation. Here, we performed transcriptome and proteome sequencing on hADSCs cultured on the "all-in-one" GMCS and the PDCS. We found that hADSCs cultured in the GMCS kept in an undifferentiation status with a high stemness index, whose transcriptome profile is closer to the adipose progenitor cells (APCs) in vivo than those cultured in the PDCS. Further, the high stemness status of hADSCs in the GMCS was maintained through regulating cell-ECM interaction. For application, bilayer scaffolds were constructed by osteo- and chondro-differentiation of hADSCs cultured in the GMCS and the PDCS. The effect of osteochondral regeneration of the bilayer scaffolds in the GMCS group was better than that in the PDCS group. This study revealed the high stemness and excellent functionality of MSCs cultured in the GMCS, which promoted the application of gel microspheres in cell culture and tissue regeneration.

Brunonianines D-F, three new C19-diterpenoid alkaloids from the Delphinium brunonianum, with therapeutic effect on ovarian cancer in vitro and in vivo.

The current standard treatment for ovarian cancer consists of surgery to reduce the size of the tumor, followed by treatment with chemotherapeutic drugs, which have major side effects. Therefore, finding a new natural product drug with fewer side effects is a strategy. Delphinium brunonianum (D. brunonianum) is a traditional Tibetan medicine, mainly from southern Tibet, China, whereas the chemical constituents in this plant remain elusive. The major metabolites in the dichloromethane fraction of D. brunonianum were analyzed and purified by HPLC and various column chromatography techniques. Nine diterpenoid alkaloids (1-9) and one amide alkaloid (10) were isolated from D. brunonianum, including three novel C19-type diterpenoid alkaloids (Brunonianines D-F) (1-3). Their structures were elucidated by 1D/2D NMR, HR-ESI-MS and single-crystal X-ray diffraction analyses. All compounds were evaluated for toxicity in four tumor cell lines. Most of the compounds exhibited potent inhibitory effects on Skov-3 cell lines, with IC50 values ranging from 2.57 to 8.05 µM. The western blotting experiment was used to further analyze the expression levels of molecules in the Bax/Bcl-2/Caspase-3 signaling pathway for compound 1. Molecular docking was performed to predict the binding modes of Brunonianine D with target proteins. In vivo experiments were also performed and evaluated in real time by monitoring the size of the Skov-3 tumor. Additionally, tumor H&E staining and the TUNEL assay used to evaluate anti-tumor effects.

Integrating Physiological Features and Proteomic Analyses Provides New Insights in Blue/Red Light-Treated Moso Bamboo (Phyllostachys edulis).

Bamboo is one of the most important nontimber forestry products in the world. Light is not only the most critical source of energy for plant photosynthesis but also involved in regulating the biological processes of plants. However, there are few reports on how blue/red light affects Moso bamboo. This study investigated the growth status and physiological responses of Moso bamboo (Phyllostachys edulis) to blue/red light treatments. The growth status of the bamboo plants was evaluated, revealing that both blue- and red-light treatments promoted plant height and overall growth. Gas exchange parameters, chlorophyll fluorescence, and enzyme activity were measured to assess the photosystem response of Moso bamboo to light treatments. Additionally, the blue light treatment led to a higher chlorophyll content and enzyme activities compared to the red light treatment. A tandem mass tag quantitative proteomics approach identified significant changes in protein abundance under different light conditions with specific response proteins associated with distinct pathways, such as photosynthesis and starch metabolism. Overall, this study provides valuable insights into the physiological and proteomic responses of Moso bamboo to blue/red light treatments, highlighting their potential impact on growth and development.

[Interaction between central nervous system and immune system after ischemic stroke and its therapeutic significance of traditional Chinese medicine].

Ischemic stroke is divided into acute phase, subacute phase, and recovery phase, with different pathological and physiological characteristics manifested at each stage. Among them, immune and inflammatory reactions persist for several days and weeks after ischemia. Ischemic stroke not only triggers local inflammation in damaged brain regions but also induces a disorder in the immune system, thereby promoting neuroinflammation and exacerbating brain damage. Therefore, conducting an in-depth analysis of the interaction between the central nervous system and the immune system after ischemic stroke, intervening in the main factors of the interaction between them, blocking pathological cascades, and thereby reducing brain inflammation have become the treatment strategies for ischemic stroke. This study summarizes and sorts out the interaction pathways between the central nervous system and the immune system. The impact of the central nervous system on the immune system can be analyzed from the perspective of the autonomic nervous system, the hypothalamic-pituitary-adrenal axis(HPA), and local inflammatory stimulation. The impact of the immune system on the central nervous system can be analyzed from the dynamic changes of immune cells. At the same time, the relevant progress in the prevention and treatment of traditional Chinese medicine(TCM) is summarized, so as to provide new insights for the analysis of complex mechanisms of TCM in preventing and treating ischemic stroke.

Effect of the STK11 mutation on therapeutic efficacy and prognosis in patients with non-small cell lung cancer: a comprehensive study based on meta-analyses and bioinformatics analyses.

BACKGROUND: This study aimed to systematically analyze the effect of a serine/threonine kinase (STK11) mutation (STK11mut) on therapeutic efficacy and prognosis in patients with non-small cell lung cancer (NSCLC). METHODS: Candidate articles were identified through a search of relevant literature published on or before April 1, 2023, in PubMed, Embase, Cochrane Library, CNKI and Wanfang databases. The extracted and analyzed data included the hazard ratios (HRs) of PFS and OS, the objective response rate (ORR) of immune checkpoint inhibitors (ICIs), and the positive rates of PD-L1 expression. The HR of PFS and OS and the merged ratios were calculated using a meta-analysis. The correlation between STK11mut and clinical characteristics was further analyzed in NSCLC datasets from public databases. RESULTS: Fourteen retrospective studies including 4317 patients with NSCLC of whom 605 had STK11mut were included. The meta-analysis revealed that the ORR of ICIs in patients with STK11mut was 10.1% (95%CI 0.9-25.2), and the positive rate of PD-L1 expression was 41.1% (95%CI 25.3-57.0). STK11mut was associated with poor PFS (HR = 1.49, 95%CI 1.28-1.74) and poor OS (HR = 1.44, 95%CI 1.24-1.67). In the bioinformatics analysis, PFS and OS in patients with STK11 alterations were worse than those in patients without alterations (p < 0.001, p = 0.002). Nutlin-3a, 5-fluorouracil, and vinorelbine may have better sensitivity in patients with STK11mut than in those with STK11wt. CONCLUSIONS: Patients with STK11-mutant NSCLC had low PD-L1 expression and ORR to ICIs, and their PFS and OS were worse than patients with STK11wt after comprehensive treatment. In the future, more reasonable systematic treatments should be explored for this subgroup of patients with STK11-mutant NSCLC.

The current clinical landscape of neonatal respiratory failure in Jiangsu Province of China: patient demographics, NICU treatment interventions, and patient outcomes.

INTRODUCTION: Neonatal respiratory failure (NRF) is a serious condition that often has high mortality and morbidity, effective interventions can be delivered in the future by identifying the risk factors associated with morbidity and mortality. However, recent advances in respiratory support have improved neonatal intensive care units (NICUs) care in China. We aimed to provide an updated review of the clinical profile and outcomes of NRF in the Jiangsu province. METHODS: Infants treated for NRF in the NICUs of 28 hospitals between March 2019 and March 2022 were retrospectively reviewed. Data collected included baseline perinatal and neonatal parameters, NICU admission- and treatment-related data, and patient outcomes in terms of mortality, major morbidity, and survival without major morbidities. RESULTS: A total of 5548 infants with NRF were included in the study. The most common primary respiratory disorder was respiratory distress syndrome (78.5%). NRF was managed with non-invasive and invasive respiratory support in 59.8% and 14.5% of patients, respectively. The application rate of surfactant therapy was 38.5%, while that of neonatal extracorporeal membrane oxygenation therapy was 0.2%. Mortality and major morbidity rates of 8.5% and 23.2% were observed, respectively. Congenital anomalies, hypoxic-ischemic encephalopathy, invasive respiratory support only and inhaled nitric oxide therapy were found to be significantly associated with the risk of death. Among surviving infants born at < 32 weeks of gestation or with a birth weight < 1500 g, caffeine therapy and repeat mechanical ventilation were demonstrated to significantly associate with increased major morbidity risk. CONCLUSION: Our study demonstrates the current clinical landscape of infants with NRF treated in the NICU, and, by proxy, highlights the ongoing advancements in the field of perinatal and neonatal intensive care in China.

Chemical constituents of Rubia tibetica Hook. f. from Tibetan medicine and cytotoxic activity evaluation.

Two unprecedented quinone compounds Rubiaxylm A (1) and Rubiaxylm B (2), along with fifteen known anthraquinones (3-17) were isolated and characterized from the roots of Rubia tibetica in Tibetan medicine. Their structures were identified through comprehensive analyses of 1D/2D NMR as well as HR-ESIMS data. Furthermore, all separated compounds were evaluated for their cytotoxic activity on A549, Caco-2, MDA-MB-231 and Skov-3 cell lines. In particular, compound 2 effectively inhibited MDA-MB-231 cells with an IC50 value of 8.15 ± 0.20 µM. Subsequently, the anti-tumor mechanism of 2 was investigated by flow cytometry, JC-1 staining, cell scratching and cell colony. These results indicated that compound 2 could inhibit the proliferation of MDA-MB-231 cells by arresting cells in the G1 phase.

Motilin, a Novel Orexigenic Factor, Involved in Feeding Regulation in Yangtze Sturgeon (Acipenser dabryanus).

Motilin is a gastrointestinal hormone that is mainly produced in the duodenum of mammals, and it is responsible for regulating appetite. However, the role and expression of motilin are poorly understood during starvation and the weaning stage, which is of great importance in the seeding cultivation of fish. In this study, the sequences of Yangtze sturgeon (Acipenser dabryanus Motilin (AdMotilin)) motilin receptor (AdMotilinR) were cloned and characterized. The results of tissue expression showed that by contrast with mammals, AdMotilin mRNA was richly expressed in the brain, whereas AdMotilinR was highly expressed in the stomach, duodenum, and brain. Weaning from a natural diet of T. Limnodrilus to commercial feed significantly promoted the expression of AdMotilin in the brain during the period from day 1 to day 10, and after re-feeding with T. Limnodrilus the change in expression of AdMotilin was partially reversed. Similarly, it was revealed that fasting increased the expression of AdMotilin in the brain (3 h, 6 h) and duodenum (3 h), and the expression of AdMotilinR in the brain (1 h) in a time-dependent manner. Furthermore, it was observed that peripheral injection of motilin-NH2 increased food intake and the filling index of the digestive tract in the Yangtze sturgeon, which was accompanied by the changes of AdMotilinR and appetite factors expression in the brain (POMC, CART, AGRP, NPY and CCK) and stomach (CCK). These results indicate that motilin acts as an indicator of nutritional status, and also serves as a novel orexigenic factor that stimulates food intake in Acipenser dabryanus. This study lays a strong foundation for the application of motilin as a biomarker in the estimation of hunger in juvenile Acipenser dabryanu during the weaning phase, and enhances the understanding of the role of motilin as a novel regulator of feeding in fish.

Renal and cardiac effects of the PDE9 inhibitor BAY 73-6691 in 5/6 nephrectomized rats.

It has been suggested that the novel selective phosphodiesterase 9 (PDE9) inhibitor may improve cardiac and renal function by blocking 3',5'-cyclic guanosine monophosphate (cGMP) degradation. 5/6 nephrectomized (5/6Nx) rats were used to investigate the effects of the PDE9 inhibitor (BAY 73-6691) on the heart and kidney. Two doses of BAY 73-6691 (1 mg/kg/day and 5 mg/kg/day) were given for 95 days. The 5/6Nx rats developed albuminuria, a decrease in serum creatinine clearance (Ccr), and elevated serum troponin T levels. Echocardiographic data showed that 5/6 nephrectomy resulted in increased fractional shortening (FS), stroke volume (SV), and left ventricular ejection fraction (EF). However, 95 days of PDE9 inhibitor treatment did not improve any cardiac and renal functional parameter. Histopathologically, 5/6 nephrectomy resulted in severe kidney and heart damage, such as renal interstitial fibrosis, glomerulosclerosis, and enlarged cardiomyocytes. Telmisartan attenuated renal interstitial fibrosis and glomerulosclerosis as well as improved cardiomyocyte size. However, except for cardiomyocyte size and renal perivascular fibrosis, BAY 73-6691 had no effect on other cardiac and renal histologic parameters. Pathway enrichment analysis using RNA sequencing data of kidney and heart tissue identified chronic kidney disease pathways, such as phosphatidylinositol 3-kinase (PI3K)-protein kinase B (Akt) signaling pathway, complement and coagulation cascades, and nuclear factor kappa B (NF-κB) signaling pathway. PDE9i did not affect any of these disease-related pathways. Two dosages of the PDE9 inhibitor BAY 73-6691 known to be effective in other rat models have only limited cardio-renal protective effects in 5/6 nephrectomized rats.

Exploiting Thin-Film Properties and Guided-Mode Resonance for Designing Ultrahigh-Figure-of-Merit Refractive Index Sensors.

Guided-mode resonance (GMR) gratings have emerged as a promising sensing technology, with a growing number of applications in diverse fields. This study aimed to identify the optimal design parameters of a simple-to-fabricate and high-performance one-dimensional GMR grating. The structural parameters of the GMR grating were optimized, and a high-refractive-index thin film was simulated on the grating surface, resulting in efficient confinement of the electric field energy within the waveguide. Numerical simulations demonstrated that the optimized GMR grating exhibited remarkable sensitivity (252 nm/RIU) and an extremely narrow full width at half maximum (2 × 10-4 nm), resulting in an ultra-high figure of merit (839,666) at an incident angle of 50°. This performance is several orders of magnitude higher than that of conventional GMR sensors. To broaden the scope of the study and to make it more relevant to practical applications, simulations were also conducted at incident angles of 60° and 70°. This holistic approach sought to develop a comprehensive understanding of the performance of the GMR-based sensor under diverse operational conditions.

Inhibition of PI3K/AKT signaling pathway prevents blood-induced heterotopic ossification of the injured tendon.

Objective: It is a common clinical phenomenon that blood infiltrates into the injured tendon caused by sports injuries, accidental injuries, and surgery. However, the role of blood infiltration into the injured tendon has not been investigated. Methods: A blood-induced rat model was established and the impact of blood infiltration on inflammation and HO of the injured tendon was assessed. Cell adhesion, viability, apoptosis, and gene expression were measured to evaluate the effect of blood treatment on tendon stem/progenitor cells (TSPCs). Then RNA-seq was used to assess transcriptomic changes in tendons in a blood infiltration environment. At last, the small molecule drug PI3K inhibitor LY294002 was used for in vivo and in vitro HO treatment. Results: Blood caused acute inflammation in the short term and more severe HO in the long term. Then we found that blood treatment increased cell apoptosis and decreased cell adhesion and tenonic gene expression of TSPCs. Furthermore, blood treatment promoted osteochondrogenic differentiation of TSPCs. Next, we used RNA-seq to find that the PI3K/AKT signaling pathway was activated in blood-treated tendon tissues. By inhibiting PI3K with a small molecule drug LY294002, the expression of osteochondrogenic genes was markedly downregulated while the expression of tenonic genes was significantly upregulated. At last, we also found that LY294002 treatment significantly reduced the tendon HO in the rat blood-induced model. Conclusion: Our findings indicate that the upregulated PI3K/AKT signaling pathway is implicated in the aggravation of tendon HO. Therefore, inhibitors targeting the PI3K/AKT pathway would be a promising approach to treat blood-induced tendon HO.

Neglected function of gastrin to reduce feeding in Siberian sturgeon (Acipenser baerii) via cholecystokinin receptor B.

Gastrin is an important intragastrointestinal hormone, but reports on its regulation of feeding behavior in fish are still scarce. This study aimed to determine the feeding regulatory function of gastrin in sturgeon. In this study, a gastrin/cholecystokinin-like peptide was identified in the genomes of sturgeon and proved to be gastrin by evolutionary tree analysis. Tissue distribution of gastrin and its receptor, cholecystokinin receptor B (CCKRB), showed that both had high mRNA abundance in the hypothalamus and gastrointestinal tract. In the duodenum, gastrin and CCKRB mRNAs were reduced at 1 h of fasting, and both were also observed in the stomach and hypothalamus in response to changes in feeding status. Sulfated gastrin 17 is the major form of gastrin in vivo. Therefore, we investigated the effect of sulfated gastrin 17 on feeding by intraperitoneal injection into Siberian sturgeon using sulfated gastrin 17. The results showed that gastrin 17 significantly reduced the cumulative feeding of Siberian sturgeon in the short term (1, 3 and 6 h) and long term (1, 2, 3, 4, 5 and 7 days). Finally, we explored the potential mechanism of feeding inhibition after intraperitoneal injection of gastrin 17 for 7 consecutive days. The results showed that gastrin 17 treatment significantly increased the mRNA levels of anorexigenic peptides (cart, cck and pyy), while it had no significant effect on the mRNA abundance of orexigenic peptides (npy and agrp). In addition, gastrin 17 treatment significantly affected the expression of appetite signaling pathways in the hypothalamus, such that the mRNA expression of ampkα1 was significantly reduced, whereas the mRNA abundance of stat3, mtor and s6k was significantly increased. In conclusion, the present study confirmed the anorectic effect of gastrin on Siberian sturgeon.

The promise of nanofluids: A bibliometric journey through advanced heat transfer fluids in heat exchanger tubes.

Thermal management is a critical challenge in advanced systems such as electric vehicles (EVs), electronic components, and photoelectric modules. Thermal alleviation is carried out through the cooling systems in which the coolant and the heat exchangers are the key components. The study examines recent literature on nanofluids and heat exchanger tubes along with state-of-the-art concepts being tested for heat transfer intensification. The performance of nanofluids in several common heat transfer tubes' geometries/configurations and the effectiveness of novel heat transfer augmentation mechanisms are presented. Promising results have been reported, showing improved heat transfer parameters with the use of nanofluids and intensification mechanisms like turbulators, fins, grooves, and variations in temperature and flow velocity. These mechanisms enhance dispersion stability, achieve a more uniform temperature distribution, and reduce the boundary layer thickness, resulting in lower tube wall temperatures. Moreover, introducing flow pulsations and magnetic effects further enhances particle mobility and heat exchange. However, there are limitations, such as increased frictional losses and pressure drop due to magnetic effects. The combination of nanofluids, novel heat exchanger tube geometries, and turbulators holds great promise for highly efficient cooling systems in the future. The study also presents a bibliometric analysis that offers valuable insights into the impact and visibility of research in the integration of nanofluids into heat transfer systems. These insights aid in identifying emerging trends and advancing the field towards more efficient and compact systems, paving the way for future advancements.

Comparative prototypes and metabolites of Du-zhi pill in normal and cerebral ischemia rats by UHPLC-Q-TOF-MS/MS method.

Du-Zhi pill (DZP) is widely used as a Chinese medicine in treating cerebral ischemia. UHPLC-Q-TOF-MS/MS techniques were used to detect and identify the metabolites in rat brain samples of normal and middle cerebral artery occlusion (MCAO) model rats administered with DZP. It was tentatively found that 43 prototypes and 93 metabolites could be identified in rat brain samples. Normal and MCAO model rat brain samples contained 19 prototype components. Eight prototype components were only detected in normal rat brain samples, while 16 were found only in MCAO model rat brain samples. It was determined that 47 metabolites had been identified in the normal rats, while 86 had been placed in MCAO model rats. There were 40 common metabolites in both normal and MCAO model rat brain samples. Seven metabolites were only detected in normal rat brain samples, while 46 were found only in MCAO rat brain samples. The comparison of metabolites in brain samples of normal and MCAO rats showed apparent differences. It was discovered that glucuronidation, methylation, acetylation, and sulfation are phase II metabolic routes of DZP, while hydrogenation, hydroxylation, and dehydroxylation are phase I metabolic routes. Moreover, hydrogenation, glucuronidation, hydroxylation, and methylation were the main metabolic pathways because of the number of metabolites identified in these metabolic pathways. The results provide a valuable reference for further research into effective substances of DZP for treating cerebral ischemia.

Disordered regions in proteusin peptides guide post-translational modification by a flavin-dependent RiPP brominase.

To biosynthesize ribosomally synthesized and post-translationally modified peptides (RiPPs), enzymes recognize and bind to the N-terminal leader region of substrate peptides which enables catalytic modification of the C-terminal core. Our current understanding of RiPP leaders is that they are short and largely unstructured. Proteusins are RiPP precursor peptides that defy this characterization as they possess unusually long leaders. Proteusin peptides have not been structurally characterized, and we possess scant understanding of how these atypical leaders engage with modifying enzymes. Here, we determine the structure of a proteusin peptide which shows that unlike other RiPP leaders, proteusin leaders are preorganized into a rigidly structured region and a smaller intrinsically disordered region. With residue level resolution gained from NMR titration experiments, the intermolecular peptide-protein interactions between proteusin leaders and a flavin-dependent brominase are mapped onto the disordered region, leaving the rigidly structured region of the proteusin leader to be functionally dispensable. Spectroscopic observations are biochemically validated to identify a binding motif in proteusin peptides that is conserved among other RiPP leaders as well. This study provides a structural characterization of the proteusin peptides and extends the paradigm of RiPP modification enzymes using not only unstructured peptides, but also structured proteins as substrates.

Chemical composition and absorption characteristics of Raw and Prepared Cassiae Semen extracts based on ultra-high-performance liquid chromatography-quadrupole Orbitrap high-resolution mass spectrometry.

In traditional Chinese medicine, the two commodity forms of Cassiae Semen Raw and Prepared Cassiae Semen, exert different clinical applications, in which Prepared Cassiae Semen is commonly used to treat liver and eye diseases. However, the material basis of Raw and Prepared Cassiae Semen remains unclear due to the limited studies on their overall composition and metabolism in vivo. In this study, an integrated analysis strategy based on ultra-high-performance liquid chromatography coupled with quadrupole-Orbitrap high-resolution mass spectrometry was established to systematically screen the prototype and metabolite constituents of Raw and Prepared Cassiae Semen. Automatic matching analysis of metabolites was performed on Compound Discoverer software based on the function of predicting metabolites. Using this strategy, a total of 77 compounds in Raw Cassiae Semen and 71 compounds in Prepared Cassiae Semen were identified. Furthermore, in vivo study, 46 prototype components and 104 metabolites from the Raw Cassiae Semen group and 41 prototype components and 87 metabolites from the Prepared Cassiae Semen group were unambiguously or preliminarily identified in mice (plasma, urine, feces, eye, and liver). This is the first study of chemical component analysis and in vivo metabolite profiling of Raw and Prepared Cassiae Semen.