Engineering CD3/CD137 dual specificity into a DLL3-targeted T-cell engager enhances T-cell infiltration and efficacy against small cell lung cancer.

Small cell lung cancer (SCLC) is an aggressive cancer for which immune checkpoint inhibitors (ICIs) have had only limited success. Bispecific T-cell engagers are promising therapeutic alternatives for ICI-resistant tumors, but not all SCLC patients are responsive. Herein, to integrate CD137 costimulatory function into a T-cell engager format and thereby augment therapeutic efficacy, we generated a CD3/CD137 dual-specific Fab and engineered a DLL3-targeted trispecific antibody (DLL3 trispecific). The CD3/CD137 dual-specific Fab was generated to competitively bind to CD3 and CD137 to prevent DLL3-independent cross-linking of CD3 and CD137, which could lead to systemic T-cell activation. We demonstrated that DLL3 trispecific induced better tumor growth control and a marked increase in the number of intratumoral T cells compared to a conventional DLL3-targeted bispecific T-cell engager. These findings suggest that DLL3 trispecific can exert potent efficacy by inducing concurrent CD137 costimulation and provide a promising therapeutic option for SCLC.

Let-7 family regulates HaCaT cell proliferation and apoptosis via the ΔNp63/PI3K/AKT pathway.

We evaluated the expression profiles of differentially expressed miRNAs (DEmiRNAs) involved in human fetal skin development via high-throughput sequencing to explore the expression difference and the regulatory role of miRNA in different stages of fetal skin development. Analysis of expression profiles of miRNAs involved collecting embryo samples via high-throughput sequencing, then bioinformatics analyses were performed to validate DEmiRNAs. A total of 363 miRNAs were differentially expressed during the early and mid-pregnancy of development, and upregulated DEmiRNAs were mainly concentrated in the let-7 family. The transfection of let-7b-5p slowed down HaCaT cell proliferation and promoted apoptosis, as evidenced by the cell counting kit-8 assay, quantitative real-time polymerase chain reaction, and flow cytometry. The double luciferin reporter assay also confirmed let-7b-5p and ΔNp63 downregulation through the combination with the 3'-untranslated region of ΔNp63. Moreover, treatment with a let-7b-5p inhibitor upregulated ΔNp63 and activated the phosphoinositide 3-kinase (PI3K)-protein kinase B (AKT) signaling pathway. The let-7b-5p caused a converse effect on HaCaT cells because of Np63 upregulation. Let-7b-5p regulates skin development by targeting ΔNp63 via PI3K-AKT signaling, contributing to future studies on skin development and clinical scar-free healing.

Engineering CD3/CD137 Dual Specificity into a DLL3-Targeted T-Cell Engager Enhances T-Cell Infiltration and Efficacy against Small-Cell Lung Cancer.

Small-cell lung cancer (SCLC) is an aggressive cancer for which immune checkpoint inhibitors (ICI) have had only limited success. Bispecific T-cell engagers are promising therapeutic alternatives for ICI-resistant tumors, but not all patients with SCLC are responsive. Herein, to integrate CD137 costimulatory function into a T-cell engager format and thereby augment therapeutic efficacy, we generated a CD3/CD137 dual-specific Fab and engineered a DLL3-targeted trispecific antibody (DLL3 trispecific). The CD3/CD137 dual-specific Fab was generated to competitively bind to CD3 and CD137 to prevent DLL3-independent cross-linking of CD3 and CD137, which could lead to systemic T-cell activation. We demonstrated that DLL3 trispecific induced better tumor growth control and a marked increase in the number of intratumoral T cells compared with a conventional DLL3-targeted bispecific T-cell engager. These findings suggest that DLL3 trispecific can exert potent efficacy by inducing concurrent CD137 costimulation and provide a promising therapeutic option for SCLC.

Network pharmacology and transcriptomic profiling elucidate the therapeutic effects of Ranunculus ternatus Thunb on liver fibrosis via MK3-NF-κB inhibition.

Activation of hepatic stellate cells (HSCs) is critical in the progression of liver fibrosis and is a promising target for anti-hepatic fibrosis drug development. Moreover, effective pharmacological interventions targeting this pathomechanism are scarce. Our study confirms the therapeutic value of ß-sitosterol, a major constituent of Ranunculus ternatus Thunb, in hepatic fibrosis and identifies its underlying mechanisms. After treatment with ß-sitosterol, CCL4-induced hepatic fibrosis was reversed in mice, while inflammatory and hepatic fibrosis indices were improved. Meanwhile, we explored the molecular mechanism of ß-sitosterol treatment for hepatic fibrosis and, based on RNA-seq results, found that the ameliorative effect of ß-sitosterol on hepatic fibrosis was associated with the MK3 and NF-κB signalling pathways. MK3, an important kinase in the MAPK pathway, plays a role in transmitting upstream and downstream signals, whereas the NF-κB signalling pathway has been shown to be associated with HSC activation. We verified the interaction between MK3 and IκB in HSC cells using endogenous Co-IP, whereas ß-sitosterol reduced the binding of MK3 to IκB and the activation of the NF-κB signalling pathway. Our findings reveal the mechanism of ß-sitosterol in the treatment of liver fibrosis, suggesting that ß-sitosterol may be a promising drug for the treatment of liver fibrosis and deserves further investigation.

Hijacking of nucleotide biosynthesis and deamidation-mediated glycolysis by an oncogenic herpesvirus.

Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent of Kaposi's sarcoma (KS) and multiple types of B cell malignancies. Emerging evidence demonstrates that KSHV reprograms host-cell central carbon metabolic pathways, which contributes to viral persistence and tumorigenesis. However, the mechanisms underlying KSHV-mediated metabolic reprogramming remain poorly understood. Carbamoyl-phosphate synthetase 2, aspartate transcarbamoylase, and dihydroorotase (CAD) is a key enzyme of the de novo pyrimidine synthesis, and was recently identified to deamidate the NF-κB subunit RelA to promote aerobic glycolysis and cell proliferation. Here we report that KSHV infection exploits CAD for nucleotide synthesis and glycolysis. Mechanistically, KSHV vCyclin binds to and hijacks cyclin-dependent kinase CDK6 to phosphorylate Ser-1900 on CAD, thereby activating CAD-mediated pyrimidine synthesis and RelA-deamidation-mediated glycolytic reprogramming. Correspondingly, genetic depletion or pharmacological inhibition of CDK6 and CAD potently impeded KSHV lytic replication and thwarted tumorigenesis of primary effusion lymphoma (PEL) cells in vitro and in vivo. Altogether, our work defines a viral metabolic reprogramming mechanism underpinning KSHV oncogenesis, which may spur the development of new strategies to treat KSHV-associated malignancies and other diseases.

Rosavin Alleviates LPS-Induced Acute Lung Injure by Modulating the TLR-4/NF-κB/MAPK Singnaling Pathways.

Acute lung injury (ALI) is a serious inflammatory disease with high morbidity and mortality. Rosavin is an anti-inflammatory and antioxidant phenylpropanoid and glucoside, which is isolated from Rhodiola rosea L. However, its potential molecular mechanisms and whether it has protective effects against lipopolysaccharide (LPS)-induced ALI remain to be elucidated. To assess the in vitro anti-inflammatory effects and anti-lung injury activity of rosavin, RAW264.7 and A549 cells were stimulated using 1 µg/mL LPS. Rosavin attenuated LPS-induced activation of the TLR-4/NF-κB signaling pathway in RAW264.7 cells and inhibited LPS-induced release of inflammatory factors in A549 cells. A mouse model of acute lung injury was constructed by intraperitoneal injection of 5 mg/kg LPS to observe the therapeutic effect of rosavin. Transcriptomics analysis and Western blot assays were utilized to verify the molecular mechanism, rosavin (20, 40, and 80 mg/kg) dose-dependently ameliorated histopathological alterations, reduced the levels of inflammatory factors, and inhibited the TLR-4/NF-κB/MAPK signaling pathway and apoptosis activation. Rosavin is a promising therapeutic candidate for acute lung injury by inhibiting the TLR-4/NF-κB/MAPK pathway.

Bile acids induce liver fibrosis through the NLRP3 inflammasome pathway and the mechanism of FXR inhibition of NLRP3 activation.

BACKGROUND: Altered patterns of bile acids (BAs) are frequently present in liver fibrosis, and BAs function as signaling molecules to initiate inflammatory responses. Therefore, this study was conducted to uncover the notably altered components of BAs and to explore the pathway of altered BA induced inflammation in the development of liver fibrosis. METHODS: Bile acids were quantified by ultraperformance liquid chromatography coupled to mass spectrometry (UPLC‒MS/MS). Cell Counting Kit-8 assays were used to determine the proliferative capacity of HSCs. Transwell assays and wound healing assays were used to determine the migratory capacity of LX2 cells. Protein expression was evaluated by western blotting. RESULTS: Plasma bile acid analysis showed higher levels of GCDCA, TCDCA, GCA and TCA in patients with liver fibrosis than in normal controls. The AUC of GCDCA was the highest. Western blotting showed that GCDCA treatment increased the expression of NLRP3-related proteins and collagen1 in vitro and significantly increased LX2 cells proliferation and migration. Furthermore, knockdown of NLRP3 or overexpression of FXR in LX2 cells decreased the expression of the above proteins, and FXR inhibited NLRP3 (ser 295) phosphorylation in vitro and vivo. In vivo, HE, Masson's trichrome, and Sirius Red staining showed that GCDCA increased collagen fibers in the mouse liver, and the expression of NLRP3-related proteins, collagen 1, and α-SMA in the liver increased significantly. However, the knockout of NLRP3 reversed these patterns. CONCLUSION: (1) Primary conjugated bile acids increased in patients with liver fibrosis; (2) GCDCA induce hepatic fibrosis via the NLRP3 inflammasome pathway; (3) FXR inhibits NLRP3 activity by restraining its phosphorylation; (4) knockdown or knockout of NLRP3 may relieve the onset of hepatic fibrosis.

Local Firework Restrictions and Ocular Trauma.

Importance: Fireworks can cause vision-threatening injuries, but the association of local legislation with the mitigation of these injuries is unclear. Objective: To evaluate the odds of firework-related ocular trauma among residents of areas where fireworks are permitted vs banned. Design, Setting, and Participants: This case-control study was conducted at a level 1 trauma center in Seattle, Washington, among 230 patients presenting with ocular trauma in the 2 weeks surrounding the Independence Day holiday, spanning June 28 to July 11, over an 8-year period (2016-2022). Exposures: Firework ban status of patient residence. Main Outcomes and Measures: Odds of firework-related injuries among residents of areas where fireworks are legal vs where they are banned, calculated as odds ratios (ORs) and 95% CIs. Results: Of 230 consultations for ocular trauma during the study period, 94 patients (mean [SD] age, 25 [14] years; 86 male patients [92%]) sustained firework-related injuries, and 136 (mean [SD] age, 43 [23] years; 104 male patients [77%]) sustained non-firework-related injuries. The odds of firework-related ocular trauma were higher among those living in an area where fireworks were legal compared with those living in an area where fireworks were banned (OR, 2.0 [95% CI, 1.2-3.5]; P = .01). In addition, the odds of firework injuries were higher for patients younger than 18 years (OR, 3.1 [95% CI, 1.7-5.8]; P < .001) and for male patients (OR, 3.3 [95% CI, 1.5-7.1]; P = .004). Firework injuries were more likely to be vision threatening (54 of 94 [57%]) compared with non-firework-related injuries (54 of 136 [40%]; OR, 2.1 [95% CI, 1.2-3.5]; P = .01). Conclusions and Relevance: This case-control study suggests that the odds of firework-related ocular trauma were slightly higher among residents of areas where fireworks were legal compared with residents of areas where fireworks were banned. Although these results suggest that local firework bans may be associated with a small reduction in the odds of firework-related ocular trauma, additional studies are warranted to assess what actions might lead to greater reductions.

Photobiomodulation therapy alleviates repeated closed head injury-induced anxiety-like behaviors.

Repeated closed head injury (rCHI) is one of the most common brain injuries. Although extensive studies have focused on how to treat rCHI-induced brain injury and reduce the possibility of developing memory deficits, the prevention of rCHI-induced anxiety has received little research attention. The current study was designed to assess the effects of photobiomodulation (PBM) therapy in preventing anxiety following rCHI. The rCHI disease model was constructed by administering three repeated closed-head injuries within an interval 5 days. 2-min daily PBM therapy using an 808 nm continuous wave laser at 350 mW/cm2 on the scalp was implemented for 20 days. We found that PBM significantly ameliorated rCHII-induced anxiety-like behaviors, neuronal apoptosis, neuronal injury, promotes astrocyte/microglial polarization to anti-inflammatory phenotype, preserves mitochondrial fusion-related protein MFN2, attenuates the elevated mitochondrial fission-related protein DRP1, and mitigates neuronal senescence. We concluded that PBM therapy possesses great potential in preventing anxiety following rCHI.

Primary Practice Emphasis Area and Diversity Among Board-Certified Ophthalmologists.

PURPOSE: To describe the ophthalmology primary practice emphasis area by underrepresented in medicine (URiM) status using the American Board of Ophthalmology (ABO) Diplomates database. DESIGN: Retrospective cohort study. METHODS: The study was based on a retrospective review of the ABO database from 1992 to 2020. The datapoints recorded included age at time of graduation and at time of certification, sex/gender, self-reported race/ethnicity, year of graduation and of certification, region of practice in the United States, and the self-reported primary practice emphasis area within ophthalmology. The URiM cohort included self-identified Black, Hispanic/Latinx, American Indian and Alaska Native, and Native Hawaiian and Other Pacific Islander individuals. Statistical analysis was conducted using Pearson χ2, Student t, and Fisher exact tests. RESULTS: A total of 575 (10.1%) ophthalmologists self-identified as URiM, vs 5132 (89.9%) as non-URiM. Diplomates who were URiM were more likely to be female and to be older at the time of ABO certification than those who were not URiM (P < .001). Over time, there was a steady decrease in the percentage of diplomates who were URiM (P < .001). There was a statistically significantly higher percentage of URiM ophthalmologists who reported glaucoma as their primary area of emphasis (P = .039) and non-URiM ophthalmologists who reported oncology, pathology, international, or genetics (P = .015), but no significant differences in the remaining subspecialties (P ≥ .123). CONCLUSIONS: There were modest differences in reported ophthalmology primary practice emphasis areas between URiM and non-URiM ABO diplomates. Despite efforts to increase diversity in ophthalmology, the percentage of graduating URiM ABO diplomates has decreased over the past 2 decades.

The effect of mandatory post-call relief on sleep and wellness in ophthalmology residents.

BACKGROUND: Multiple duty hour reforms have been implemented to optimize resident wellness through increasing opportunities for sleep recovery, but few studies have recorded objectively measured sleep or shown direct sleep and wellness benefits from such interventions. This study seeks to determine whether mandatory post-call relief policies with a partial night float system improved resident sleep, activity, and burnout among ophthalmology residents taking home call. METHODS: We conducted a two group cohort study of ophthalmology residents at the University Washington comparing post graduate year-2 (PGY-2) resident sleep, activity, and burnout between the optional post-call relief group from July 1, 2017 to June 30, 2019 to the mandatory post-call relief group from July 1, 2019 to June 30, 2021. RESULTS: Of twenty total residents participating in the survey portion, 18 residents participated in the sleep and activity tracking portion of the study, 9 in in the optional post-call relief cohort, and 9 in the mandatory post-call relief cohort. The mandatory post-call relief group recorded longer total sleep on call than the optional post-call relief group (p < 0.001). There was no difference in overnight sleep recorded on call (median 3.4 h), but residents recorded more time napping in the mandatory post-call relief cohort (p < 0.001). There was no significant difference between cohorts in amount of sleep while not on call. Residents in the mandatory post-call relief cohort recorded higher average daily steps, higher exercise time, and lower sedentary time than residents in the optional post-call relief cohort (p < 0.001). They also recorded lower median emotional exhaustion on the Maslach Burnout Inventory and lower stress in the Depression and Anxiety Stress Scale in the mandatory post-call relief cohort (p = 0.008). CONCLUSIONS: Implementation of mandatory post-call relief policies with a partial night-float system among PGY-2 residents was associated with more post-call naps with more overall physical activity, lower emotional exhaustion scores, and lower stress scores, despite no changes to overnight sleep on call or total sleep. Although sample size limits interpretation of data, implementation of mandatory post call relief could be considered to improve post-call sleep in programs with home call.

[Three new diterpenoids from whole herb of Carpesium cernuum].

The study investigated the chemical constituents from the whole herb of Carpesium cernuum. Three new diterpenoids were isolated from the whole herb of C. cernuum by column chromatography on silica gel, Sephadex LH-20, and semi-preparative HPLC. Their structures were identified by MS, NMR and other spectral techniques. The isolates were identified as(5Z)-2-oxo-2, 10, 14-trimethylhexadeca-5, 13-diene-11α, 18-diol(1),(2E, 10E)-7-[(acetyloxy)methyl]-3, 11, 15-trimethylhexadeca-2, 10, 14-triene-1, 12α-diol(2),(2E, 6Z)-3, 11, 15-trimethylhexadeca-2, 6, 14-triene-1, 12α, 19-triol(3), respectively. The cytotoxic activity of compounds 1-3 were investigated with DU-145, MCF-7, and A549 cells by MTT. The results showed that compound 1 and 3 had certain inhibitory effects on MCF-7 cells, with the inhibition rates of 45.06% and 29.40%, respectively.

[Comparative study of purgative pharmacological effects and mechanisms of Moringa oleifera leaves and Rhei Radix et Rhizoma].

Moringa oleifera leaves are known for their "Virechana"(purgative) effect in Ayurvedic medicine in India. This study compared the purgative effects and mechanisms of M. oleifera leaves with the reference Rhei Radix et Rhizoma to establish a foundation for the further application of M. oleifera leaves in traditional Chinese medicine(TCM). Using network pharmacology and molecular docking methods, this study identified the material basis, common targets, and signaling pathways through which Rhei Radix et Rhizoma and M. oleifera leaves exerted their purgative pharmacological effects. A low-fiber diet-induced constipation mouse model was established to measure fecal parameters and small intestinal propulsion rate, and histological changes in the colon were observed using HE staining. Relative expression levels of relevant genes and target proteins were assessed using RT-qPCR and immunohistochemistry, respectively. The results showed that mapping the targets of Rhei Radix et Rhizoma and M. oleifera leaves onto the biological process network of constipation revealed close proximity, indicating that they may exert their therapeutic effects on constipation through similar biological processes. Molecular docking results indicated that compounds such as sennoside C and isoquercitrin could target serine/threonine protein kinases(AKT1) and mitogen-activated protein kinase 3(MAPK3), thereby affecting MAPK and calcium signaling pathways to promote defecation. Animal experiments demonstrated that both M. oleifera leaves and Rhei Radix et Rhizoma increased the number of fecal pellets and water content in constipated mice, improved small intestine motility, colon mucosal thickness, and muscle layer thickness, upregulated the gene expression levels of AKT1 and MAPK3 in the colon, and downregulated the expression of AQP3 protein. These findings suggest that M. oleifera leaves and Rhei Radix et Rhizoma share similarities in their therapeutic efficacy and mechanisms for treating constipation. Using Rhei Radix et Rhizoma as a reference can provide a better understanding of the characteristics of the "Virechana"(purgative) effect of M. oleifera leaves in TCM.

Clinical efficacy and metabolomic analysis of ozone major autohemotherapy for the treatment of herpes zoster.

Introduction: It is essential to understand the underlying changes in the patients' metabolic profiles that may be indicative of the therapy's effectiveness. Aim: To prospectively analyse the clinical efficacy of ozone autohemotherapy in the treatment of acute herpes zoster and investigate its impact on serum metabolomics. Material and methods: A total of 76 patients with acute herpes zoster between May 2018 and June 2020 were enrolled and divided into an experimental group and a control group. The pain location, Numeric Rating Scale (NRS) scores before and after treatment (1 week, 1 month, 3 months, and 6 months post-treatment), medication usage, and Quality of Sleep (QS) scores were prospectively analysed. Additionally, serum metabolomic data were obtained and analysed before and 6 months after the treatment. Results: There were statistically significant differences in the total NRS scores before and after ozone autohemotherapy (p < 0.05). The NRS scores of both groups significantly decreased (p < 0.05). At the 6-month follow-up, no patients were lost, and 83 patients completed the follow-up. The NRS improvement at 1 week, 1 month, 3 months, and 6 months post-treatment in the experimental group was significantly lower than that in the control group (p < 0.05). There was no significant difference in the medication usage (pregabalin or tramadol sustained-release tablets) between the two groups (p > 0.05). One month after treatment, the QS score improvement in the diabetes group was significantly lower than that in the non-diabetes group (p < 0.05). Serum metabolomics analysis revealed three significantly decreased metabolites, namely creatine, adipate, and glucose, after treatment. Conclusions: Ozone autohemotherapy is an effective treatment for acute herpes zoster patients and can rapidly and effectively alleviate pain symptoms in the short term. The changes in serum metabolomics may provide further insights into the treatment mechanism.

Closure of a Chronic Traumatic Macular Hole Following Phacoemulsification Surgery.

PURPOSE: To report a case of chronic traumatic macular hole closure following an uncomplicated phacoemulsification surgery. METHODS: Retrospective chart review with optical coherence tomography imaging. RESULTS: 42-year-old woman with a 20-year history of a traumatic macular hole and cataract in the right eye underwent an uncomplicated phacoemulsification surgery. Following surgery, the patient was prescribed prednisolone acetate 1% four times per day, which was tapered off by postoperative month 1. By postoperative month 1, the full-thickness macular hole had closed. CONCLUSION: This unique case illustrates the closure of a full-thickness macular hole following cataract surgery. We hypothesize that closure of the macular hole was aided by the use of topical steroids in the postoperative period, allowing for resolution of the cystic intraretinal fluid and hole closure.

Resident Sleep During Traditional Home Call Compared to Night Float.

Purpose This article aims to compare resident sleep while on night float with a traditional home call. Methods We conducted a crossover observational study assessing sleep patterns of seven postgraduate year-2 ophthalmology residents at the University of Washington from 2019 to 2021 using the Fitbit Alta HR device. Overnight call was scheduled from 5 p.m. to 8 a.m. on weekdays, and 8 a.m. to 8 a.m. on weekends. The residency program implemented a partial night float rotation, during which two to three nights of consecutive call were assigned to a resident without other clinical duties. Sleep was recorded using the Fitbit Alta HR for residents while on a 5-week partial night float rotation, on 10-week home call rotations, with postcall relief, and for stretches of seven or more days without call responsibilities. Mixed model regression analysis was used to compare average sleep on home call, night float, and periods without call. Results Sleep data were recorded for a total of 1,015 nights, including 503 nights on home call rotation and 230 nights on night float rotation. Residents slept more during periods away from call compared to either night float or home call rotations ( p < 0.001). Residents experienced increased average overall sleep during 10-week rotations on night float compared to home call ( p = 0.008). While there was no difference in overnight sleep on call between night float and home call ( p = 0.701), residents experienced more sleep overall while on call on night float compared to home call due to more sleep being recorded during postcall naps ( p = 0.016). Conclusion Implementing a night float system can increase resident sleep by allowing for more sleep recovery during time away from clinical duties.

Mechanistic insights into the role of herpes simplex virus 1 in Alzheimer's disease.

Alzheimer's Disease (AD) is an aging-associated neurodegenerative disorder, threatening millions of people worldwide. The onset and progression of AD can be accelerated by environmental risk factors, such as bacterial and viral infections. Human herpesviruses are ubiquitous infectious agents that underpin numerous inflammatory disorders including neurodegenerative diseases. Published studies concerning human herpesviruses in AD imply an active role HSV-1 in the pathogenesis of AD. This review will summarize the current understanding of HSV-1 infection in AD and highlight some barriers to advance this emerging field.

Plexiform Schwannoma of Brachial Plexus in Axilla: A Rare Case Report.

The most common tumours in the brachial plexus are benign schwannomas, followed by neurofibromas and malignancies, originating from the peripheral nerve sheath. The clinical manifestations of brachial plexus tumours are variable according to their location, extension, neurological elements involved and pathology. Brachial plexus tumours are rare in the upper extremity, and axillary schwannoma is uncommon. This case reports a 59-year-old woman with a tumour in her left axilla for two years, gradually enlarging with numbness in her left little finger. Microsurgical interfascicular dissection operation was performed to remove the tumour. Νumbness disappeared after the procedure, and no tumour recurrence was observed during the 30-month follow-up. To the best of our knowledge, plexiform schwannoma of the brachial plexus in the axilla has not been reported so far. In this article, such a case is reported, where this tumour was diagnosed by the histopathological examination and confirmed with immunohistochemistry.

Understory fuel loads and the impact factors of Quercus mongolica natural secondary forest in Hebei Pro-vince, China.

We investigated understory fuel loads of Quercus mongolica natural secondary forests in Hebei Province, China. We analyzed the effects of stand factors, topographic factors, and ground cover factors on the quantity and composition of fuel, established the dynamic models of understory fuel loads, and proposed management measures. The results showed that the understory total fuel load in Q. mongolica natural secondary forests was 11.68 t·hm-2, which exceeded the forest fire potential threshold (10 t·hm-2). The understory dead fuel load was mainly humus, and the understory living fuel load was mainly shrubs. The 1 h time-lag fuel load increased significantly with increasing canopy density, stand density, stand age, and litter thickness. The 10 h time-lag fuel load increased signi-ficantly with increasing stand density, average tree height, and litter thickness. Humus load decreased significantly with increasing altitude and increased significantly with increasing humus thickness. Herb load increased significantly with increasing sunny slope orientation and herbal coverage. Shrub load increased significantly with increasing slope degree, shrub coverage, and humus thickness. Understory total fuel load decreased significantly with increasing altitude, and increased significantly with increasing stand density, humus thickness, and litter thickness. The results of stepwise regression analysis indicated that stand density, humus thickness, and altitude could better predict the understory total fuel load (Radj2=0.775). Therefore, more attention should be paid on the control of stand density of Q. mongolica natural secondary forest in Hebei Province. Cleaning of litters and humus on the ground would help prevent forest fires scientifically and effectively.

[Component identification and analysis in vivo of Sanhan Huashi formula].

Sanhan Huashi formula(SHF) is the intermediate of a newly approved traditional Chinese medicine(TCM) Sanhan Huashi Granules for the treatment of COVID-19 infection. The chemical composition of SHF is complex since it contains 20 single herbal medicines. In this study, UHPLC-Orbitrap Exploris 240 was used to identify the chemical components in SHF and in rat plasma, lung and feces after oral administration of SHF, and heat map was plotted for characterizing the distribution of the chemical components. Chromatographic separation was conducted on a Waters ACQUITY UPLC BEH C_(18)(2.1 mm×100 mm, 1.7 µm) using 0.1% formic acid(A)-acetonitrile(B) as mobile phases in a gradient elution. Electrospray ionization(ESI) source was used to acquire data in positive and negative mode. By reference to quasi-molecular ions and MS/MS fragment ions and in combination with MS spectra of reference substances and compound information in literature reports, 80 components were identified in SHF, including 14 flavonoids, 13 coumarins, 5 lignans, 12 amino-compounds, 6 terpenes and 30 other compounds; 40 chemical components were identified in rat plasma, 27 in lung and 56 in feces. Component identification and characterization of SHF in vitro and in vivo lay foundations for disclosure of its pharmacodynamic substances and elucidation of the scientific connotation.