[Study on the application value of portable pulse oximeter in adult patients with obstructive sleep apnea]

Objective: To evaluate the application value of portable pulse oximeter in adult obstructive sleep apnea (OSA). Methods: This study prospectively enrolled adult patients who underwent polysomnography (PSG) due to snoring at the Respiratory and Sleep Medicine Department of Peking University People's Hospital from July 2022 to July 2023. During PSG monitoring, CS-WOxi was continuously used to monitor blood oxygen levels. The consistency between 3% oxygen desaturation index (ODI3) measured by portable pulse oximeter and ODI3 of polysomnography was evaluated using difference test, Pearson's correlation coefficient, and Bland-altman method. Receiver operating characteristic curve was used to determine the optimal threshold for diagnosing OSA. Results: A total of 184 subjects were included, including 121 males (65.8%) and 63 females (34.2%). The mean age was 46.0 (34.3, 59.0) years, body mass index was 26.0 (23.3, 29.6) kg/m², and the apnea-hypopnea index was 18.2 (5.8, 40.8) events/h. There was a significant difference between CS-ODI3 and PSG-ODI3 [17.1(6.2, 42.7) vs. 14.0(2.9, 32.6), P<0.001], and the Pearson correlation coefficient was 0.93 (P<0.001). There was a good correlation between CS-ODI3 and PSG-AHI (r=0.92, P<0.001). Bland-Altman consistency test showed that the average difference between the two was 0.7 events/h, and the 95% consistency limit was (-17.9, 19.3 events/h). When the CS-ODI3≥5 events/h was used to identify OSA, the sensitivity was 94.4%, the specificity was 80.0%, and the accuracy was 91.3%. When PSG-AHI≥5 events/h was used as the diagnostic criteria, the area under the receiver operating characteristic curve was 0.933. Conclusion: Portable pulse oximeter can monitor pulse oxygen saturation accurately and has good sensitivity and specificity for OSA high-risk patients, and is a reliable tool for OSA screening.

Rapid profiling of transcription factor-cofactor interaction networks reveals principles of epigenetic regulation

Transcription factor (TF)-cofactor (COF) interactions define dynamic, cell-specific networks that govern gene expression; however, these networks are understudied due to a lack of methods for high-throughput profiling of DNA-bound TF-COF complexes. Here we describe the Cofactor Recruitment (CoRec) method for rapid profiling of cell-specific TF-COF complexes. We define a lysine acetyltransferase (KAT)-TF network in resting and stimulated T cells. We find promiscuous recruitment of KATs for many TFs and that 35% of KAT-TF interactions are condition specific. KAT-TF interactions identify NF-κB as a primary regulator of acutely induced H3K27ac. Finally, we find that heterotypic clustering of CBP/P300-recruiting TFs is a strong predictor of total promoter H3K27ac. Our data supports clustering of TF sites that broadly recruit KATs as a mechanism for widespread co-occurring histone acetylation marks. CoRec can be readily applied to different cell systems and provides a powerful approach to define TF-COF networks impacting chromatin state and gene regulation.

Forb stability, dwarf shrub stability and species asynchrony regulate ecosystem stability along an experimental precipitation gradient in a semi-arid desert grassland

Precipitation pattern changes may affect plant biodiversity, which could impact ecosystem stability. However, the effects of changes in precipitation regime on ecosystem stability and their potential mechanisms are still unclear. We conducted a 3-year field manipulation experiment with five precipitation treatments (-40%, -20%, 0% (CK), +20% and +40% of ambient growing season precipitation) in a semi-arid desert grassland to examine the effects of precipitation alterations on functional group stability, species asynchrony, and diversity, and the underlying mchanisms of ecosystem stability using structural equation modelling. Alterations in precipitation had different effects on community biomass and functional group biomass. Moreover, ecosystem stability was mainly driven by forb stability (path coefficient = 0.79). Changes in precipitation had significant effects on soil dissolved inorganic N (P < 0.01) further affecting ecosystem stability through species asynchrony (path coefficient = 0.25). Dwarf shrubs had a stabilizing effect on ecosystem stability (path coefficient = 0.32), mainly via deep roots. Ecosystem stability tended to be lower in the -40% (4.72) and +40% (2.74) precipitation treatments. The common reduction in species asynchrony and stability of forb and dwarf shrub functional groups resulted in lower ecosystem stability under the -40% treatment. The lower stability under the +40% treatment might be ascribed to unimproved dwarf shrub stability. Higher dwarf shrub and forb stability contributed to higher ecosystem stability under normal precipitation changes (±20% treatments) and CK. Species diversity was not a crucial driver of ecosystem stability. Our results indicate that precipitation alteration can regulate ecosystem stability via functional group stability (e.g. forb stability, dwarf shrub stability) and species asynchrony in a semiarid desert grassland.

[Auxiliary diagnosis of visceral leishmaniasis with metagenomic next-generation sequencing: a case report]

This case report summarizes the experience from diagnosis and treatment of a patient with repeated high fever, hepatosplenomegaly and pancytopenia. Following exclusion of bacterial, viral, fungal infections and hematological diseases, metagenomic next-generation sequencing of the patient's peripheral blood revealed Leishmania infantum infection, and rK39 rapid diagnostic test showed positive for anti-Leishmania antibody, while microscopic examination of bone marrow smears identified Leishmania amastigotes. Therefore, the case was definitively diagnosed as visceral leishmaniasis, and given anti-infective treatment with sodium antimony gluconate and hormone, hepatoprotection, elevation of white blood cell counts and personalized nursing. Then, the case was cured and discharged from hospital. Metagenomic next-generation sequencing is of great value in etiological detection of fever patients with unknown causes, which deserves widespread clinical applications.

[Analysis of clinical data of necrotizing fasciitis secondary to intestinal fistulas and screening the mortality risk factors]

Objective: To analyze the clinical data and to screen the mortality risk factors of necrotizing fasciitis (NF) secondary to intestinal fistulas (NFsIF). Methods: This study was a retrospective observational study. The data of all NFsIF cases who met the inclusion criteria and were admitted into Shandong Provincial Hospital Affiliated to Shandong First Medical University (hereinafter referred to as our unit) from January 2000 to October 2023, and in PubMed, Web of Science, Scopus, China National Knowledge Infrastructure, and Chinese Medical Journal Network databases from its establishment to October 2023 were retrieved and screened. Based on clinical outcomes, the cases were divided into survival group (47 males and 24 females) and death group (16 males and 7 females), and the mortality rate was calculated. Clinical data of patients in the two groups including age, underlying diseases (most related to NF), symptom duration before presentation, white blood cell count, causes of NF, signs of peritonitis, scope of NF involvement, and intestinal management and wound management measures were compared and analyzed to screen the risk factors of death in 94 patients with NFsIF. Results: A total of 94 valid cases were collected, including 90 patients reported in the literature and 4 patients admitted to our unit, with the mortality rate of patients being 24.5% (23/94). Univariate analysis showed that there were no statistically significant differences in age, underlying diseases, symptom duration before presentation, white blood cell count, causes of NF, signs of peritonitis, scope of NF involvement between patients in the two groups (P>0.05); there were statistically significant differences in intestinal treatment and wound treatment between the two groups (with χ2 values of 17.97 and 8.33, respectively, P<0.05). Multivariate logistic regression analysis showed that both intestinal treatment measures and wound treatments measures were independent risk factors for death in 94 NFsIF patients, among which first-stage colostomy+late-stage reconstruction and negative presssure therapy had higher protective effects (with odds ratios of 0.05 and 0.27, respectively, 95% confidence intervals of 0.01-0.33 and 0.08-0.88, respectively, P<0.05). Conclusions: The mortality risk of patients with NFsIF is high. Based on comprehensive treatments, active intestinal and wound treatment may be the key to avoid death, with first-stage colostomy+late-stage reconstruction and negative pressure therapy having higher protective effects.

Changes in brain susceptibility in Wilson's disease patients: a quantitative susceptibility mapping study

AIM

To assess changes in the susceptibility of the caudate nucleus (CN), putamen, and globus pallidus (GP) in patients with neurological and hepatic Wilson's disease (WD) by quantitative susceptibility mapping (QSM).

MATERIAL AND METHODS

The brain MRI images of 33 patients diagnosed with WD and 20 age-matched controls were analysed retrospectively. All participants underwent brain T1-weighted, T2-weighted, and QSM imaging using a 1.5 T magnetic resonance imaging (MRI) machine. QSM maps were evaluated with the STISuite toolbox. The quantitative susceptibility levels of the CN, putamen, and GP were analysed using region of interest analysis on QSM maps. Differences among neurological WD patients, hepatic patients, and controls were determined.

RESULTS

Susceptibility levels were significantly higher for all examined structures (CN, putamen and GP) in patients with neurological WD compared with controls (all p<0.05) and hepatic WD patients (all p<0.05). No statistically significant differences were found in susceptibility levels between patients with hepatic WD and controls (all p>0.05).

CONCLUSION

The QSM technique is a valuable tool for detecting changes in brain susceptibility in WD patients, indicating abnormal metal deposition. Notably, the current findings suggest that neurological WD patients exhibit more severe susceptibility changes compared with hepatic WD patients. Therefore, QSM can be utilised as a complementary method to detect brain injury in WD patients.

The oncogenic mechanisms of the Janus kinase-signal transducer and activator of transcription pathway in digestive tract tumors

Digestive tract tumors are heterogeneous and involve the dysregulation of multiple signaling pathways. The Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathway plays a notable role in the oncogenesis of digestive tract tumors. Typically activated by pro-inflammatory cytokines, it regulates important biological processes, such as cell growth, differentiation, apoptosis, immune responses, and inflammation. The aberrant activation of this pathway manifests in different forms, including mutations in JAKs, overexpression of cytokine receptors, and sustained STAT activation, and contributes to promoting the malignant characteristics of cancer cells, including uncontrolled proliferation, resistance to apoptosis, enhanced invasion and metastasis, angiogenesis, acquisition of stem-like properties, and drug resistance. Numerous studies have shown that aberrant activation of the JAK-STAT pathway is closely related to the development and progression of digestive tract tumors, contributing to tumor survival, angiogenesis, changes in the tumor microenvironment, and even immune escape processes. In addition, this signaling pathway also affects the sensitivity of digestive tract tumors to chemotherapy and targeted therapy. Therefore, it is crucial to comprehensively understand the oncogenic mechanisms underlying the JAK-STAT pathway in order to develop effective therapeutic strategies against digestive tract tumors. Currently, several JAK-STAT inhibitors are undergoing clinical and preclinical trials as potential treatments for various human diseases. However, further investigation is required to determine the role of this pathway, as well as the effectiveness and safety of its inhibitors, especially in the context of digestive tract tumors. In this review, we provide an overview of the structure, classic activation, and negative regulation of the JAK-STAT pathway. Furthermore, we discuss the pathogenic mechanisms of JAK-STAT signaling in different digestive tract tumors, with the aim of identifying potential novel therapeutic targets. Video Abstract.

Genomic evolution and insights into agronomic trait innovations of Sesamum species

Sesame is an ancient oilseed crop with high oil content and quality. However, the evolutionary history and genetic mechanisms of its valuable agronomic traits remain unclear. Here, we report chromosome-scale genomes of cultivated sesame (Sesamum indicum L.) and six wild Sesamum species, representing all three karyotypes within this genus. Karyotyping and genome-based phylogenic analysis revealed the evolutionary route of Sesamum species from n = 13 to n = 16 and revealed that allotetraploidization occurred in the wild species Sesamum radiatum. Early divergence of the Sesamum genus (48.5-19.7 million years ago) during the Tertiary period and its ancient phylogenic position within eudicots were observed. Pan-genome analysis revealed 9164 core gene families in the 7 Sesamum species. These families are significantly enriched in various metabolic pathways, including fatty acid (FA) metabolism and FA biosynthesis. Structural variations in SiPT1 and SiDT1 within the phosphatidyl ethanolamine-binding protein gene family lead to the genomic evolution of plant-architecture and inflorescence-development phenotypes in Sesamum. A genome-wide association study (GWAS) of an interspecific population and genome comparisons revealed a long terminal repeat insertion and a sequence deletion in DIR genes of wild Sesamum angustifolium and cultivated sesame, respectively; both variations independently cause high susceptibility to Fusarium wilt disease. A GWAS of 560 sesame accessions combined with an overexpression study confirmed that the NAC1 and PPO genes play an important role in upregulating oil content of sesame. Our study provides high-quality genomic resources for cultivated and wild Sesamum species and insights that can improve molecular breeding strategies for sesame and other oilseed crops.

Visual detection of fowl adenovirus serotype 4 via a portable CRISPR/Cas13a-based lateral flow assay

The widespread occurrence of fowl adenovirus serotype 4 (FAdV-4)-induced hepatitis-hydropericardium syndrome (HHS) has led to significant economic losses for the poultry industry. A sensitive, accurate, and practical FAdV-4 diagnostic approach is urgently required to limit the incidence of the disease. In the present study, a practical method for detecting FAdV-4 was developed using the CRISPR/Cas13a system and recombinase-aided amplification. The approach was based on 37°C isothermal detection with visible results being achieved. The detection limit of the target gene with this approach was only 101 copies/μl, making it very sensitive and specific. Clinical samples fared well when tested with the Cas13a detection method. For identifying FAdV-4, this novel detection approach was found to be sensitive, specific, and effective.RESEARCH HIGHLIGHTS First study using the CRISPR/Cas13a-based lateral flow detection assay for FAdV-4 detection.The results can be observed by the naked eye.The developed assay could provide an alternative tool for detection of FAdV-4 with minimal equipment.

Integrated analysis of noncoding RNAs and mRNAs reveals their potential roles in chicken spleen response to Klebsiella variicola infection

Klebsiella variicola is an emerging pathogen that has become a threat to human and animal health. There is evidence that long noncoding RNAs (lncRNAs) are involved in a host cell's response to microbial infections. However, no study has defined the link between K. variicola pathogenesis and lncRNAs until now. We used RNA sequencing to comprehensively analyze the lncRNAs and mRNAs in the chicken spleen after K. variicola infection. In total, we identified 2896 differentially expressed mRNAs and 578 differentially expressed lncRNAs. To examine the potential functions of these lncRNAs, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes signaling pathway enrichment analyses were performed on the target mRNAs of these differently expressed lncRNAs. The results suggested that lncRNAs play essential roles in modulating mRNA expression and triggering downstream immune signaling pathways to regulate the immune response in the chicken spleen. Using previous microRNA sequencing data, we constructed lncRNA-miRNA-mRNA regulatory networks to clarify the regulatory mechanisms in the chicken immune system. Several potential regulatory pairs related to K. variicola infection were found, involving XR_001467769.2, TCONS_00018386, gga-miR-132a-3p, gga-miR-132b-5p, gga-miR-2954, and novel62_mature. In conclusion, our findings make a significant contribution towards understanding the role of lncRNA in chicken spleen cells during K. variicola infection, thereby establishing a solid foundation for future research in this area.

B7 Induces Apoptosis in Colorectal Cancer Cells by Regulating the Expression of Caspase-3 and Inhibits Autophagy

Purpose

Heterocyclic compounds are organic compounds with heterocyclic structures, which are common in drug molecules. They include pyrazines with diverse functions, including anti-cancer, antimicrobial, antidiabetic, and anticholinergic activities. In this study a new small molecular compound B7 based on tetrazolium substituted pyrazine was synthesized and its effect on the progression of colorectal cancer (CRC) and its potential mechanism were investigated.

Methods

We synthesized a series of tetrazolium-substituted pyrazine compounds by chemoenzymatic method. NCM460 (Human), HCT116 (Human), SW480 (Human) cell lines were selected to analyse the inhibitory effect of B7 on CRC by CCK-8, apoptosis, cell migration and invasion, qPCR, Western blotting, molecular docking, immunofluorescence. Moreover, a CRC xenograft model of mice was used to analyzed the role of B7 in vivo.

Results

Among these compounds, 3-methyl-5je-6-bis (1H-tetrazole-5-yl) pyrazine-2-carboxylic acid (B7) inhibited CRC cell proliferation and induced apoptosis. The expression of Caspase-3 was increased after B7 treatment. In addition, the mitochondria abnormalities was observed in B7 group due to decrease the expression of Beclin-1. In addition, B7 inhibited the migration and invasion in CRC cells. Finally, the results showed that B7 had anti-tumor activity in CRC xenograft model of mice.

Conclusion

In summary, compound B7 was synthesized efficiently using tetrazolium-substituted pyrazine via a chemoenzymatic method. Moreover, B7 have ability to regulate the expression of Caspase-3 which induced apoptosis in CRC cells. In addition, decreased Beclin-1 expression after B7 treatment, indicating inhibited autophagy. This study showed that B7 effectively induced apoptosis and inhibited autophagy in CRC cells.

The Role of Radiotherapy in Patients with Refractory Hodgkin Lymphoma after Brentuximab Vedotin and -/or Immune Checkpoint Inhibitors

PURPOSE/OBJECTIVE(S)

Brentuximab vedotin (BV) and immune checkpoint inhibitors (ICIs) had important roles in the treatment of relapse or refractory (R/R) Hodgkin lymphoma (HL). Treatment of refractory disease after BV and -/or ICIs remains a challenge. This study was conducted to evaluate the efficacy and safety of radiotherapy for R/R HL after failure to BV or ICIs.

MATERIALS/METHODS

We retrospectively analyzed patients in two institutions with R/R HL who had failed after first-line therapy, and were refractory to BV or ICIs, and received radiotherapy (RT) thereafter. The overall response rate (ORR), duration of response (DOR), progression-free survival (PFS) and overall survival (OS) were analyzed.

RESULTS

A total of 19 patients were enrolled. First-line systemic therapy consisted of ABVD (84.2%), AVD + ICIs (10.5%) and BEACOPP (5.3%), respectively. After first-line therapy, 15 patients (78.9%) were refractory, and 4 patients (21.1%) relapsed. After diagnosis of R/R HL, 8 patients (42.1%) received BV, and 17 patients (89.5%) received ICIs. RT was delivered in all 19 patients who failed after BV or ICIs. In 16 efficacy-evaluable patients, the ORR and CR rate were 100% and 100%. The median DOR was 17.2 months (range, 7.9 to 46.7 months). 3 patients progressed at outside of the radiation field. The in-field-response rate was 100%. The 12-month PFS and OS were 84.4% and 100%, respectively. No patients were reported with sever adverse events.

CONCLUSION

This study concluded that radiotherapy was effective and safe for refractory HL after BV or ICIs. Further prospective studies were warranted.

Altered Proteomic Profile of Exosomes Secreted from Vero Cells Infected with Porcine Epidemic Diarrhea Virus

Porcine epidemic diarrhea virus (PEDV) infection causes severe diarrhea in pigs and can be fatal in newborn piglets. Exosomes are extracellular vesicles secreted by cells that transfer biologically active proteins, lipids, and RNA to neighboring or distant cells. Herein, the morphology, particle size, and secretion of exosomes derived from a control and PEDV-infected group are examined, followed by a proteomic analysis of the exosomes. The results show that the exosomes secreted from the Vero cells had a typical cup-shaped structure. The average particle size of the exosomes from the PEDV-infected group was 112.4 nm, whereas that from the control group was 150.8 nm. The exosome density analysis and characteristic protein determination revealed that the content of exosomes in the PEDV-infected group was significantly higher than that in the control group. The quantitative proteomics assays revealed 544 differentially expressed proteins (DEPs) in the PEDV-infected group's exosomes compared with those in the controls, with 236 upregulated and 308 downregulated proteins. The DEPs were closely associated with cellular regulatory pathways, such as the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)-protein kinase B (Akt) signaling pathway, extracellular matrix-receptor interaction, focal adhesion, and cytoskeletal regulation. These findings provide the basis for further investigation of the pathogenic mechanisms of PEDV and the discovery of novel antiviral targets.

[Efficacy of arteriovenous argatroban versus heparin flush anticoagulation after cardiovascular surgery]

Objective: To compare the effects of arteriovenous argatroban and heparin flushes on platelet count and assess the occurrence of heparin-induced thrombocytopenia (HIT) and other complications in patients undergoing cardiovascular surgeries. Methods: A single-center, prospective randomized control study was conducted. Patients who underwent cardiovascular surgery at Fuwai Hospital, Chinese Academy of Medical Sciences from March to December 2019 were randomly divided into the argatroban group (250 ml normal saline plus 2.5 mg of argatroban) and the heparin group (250 ml normal saline plus 10 mg of heparin). Platelet count, hemorrhage, and thrombosis were assessed. The 4T scores of HIT, the incidences of HIT and other complications were also evaluated. Results: A total of 491 patients (307 males and 184 females) were included in the study, with a mean age of (52.3±13.7) years. There were 245 cases in the argatroban group and 246 cases in the heparin group, respectively. There was no statistically significant difference in the preoperative platelet count between the argatroban and heparin groups [198.0 (161.0, 248.0)×10⁹/L vs 194.0 (157.2, 243.8)×10⁹/L, P=0.498]. Likewise, there were no statistically significant differences in the platelet count between the argatroban and heparin groups at 12 h, 1 day, and 5 days after operation [127.0 (100.0, 154.0)×10⁹/L vs 121.5 (90.2, 149.0)×10⁹/L, 126.0 (97.0, 162.0)×10⁹/L vs 123.5 (88.0, 151.0)×10⁹/L, 168.0 (130.0, 215.0) ×10⁹/L vs 161.0 (101.0, 210.5)×10⁹/L] (repeated measures ANOVA between groups: F=3.327, P=0.069; time comparison: F=532.523, P<0.001; time interaction between groups: F=0.675, P=0.512). The proportion of 4T scores of medium and high scores (≥4)[9.8% (24/245) vs 10.6% (26/246), P=0.777] and incidence of HIT antibody positive [1.63% (4/245) vs 1.63% (4/246), P=0.726] were similar between argatroban group and the heparin group. Mechanical ventilation time was shorter in the argatroban group than that in the heparin group [13.0 (11.0, 21.0) vs 15.5 (12.0, 21.0) h, P=0.020]. Conclusion: Compared with heparin, routine management with argatroban for arteriovenous flush in patients undergoing cardiovascular surgery does not affect the HIT incidence.

Abstract 1785: Multi-step engineering of gene-edited CAR T cells using RNA lipid nanoparticles

Autologous chimeric antigen receptor (CAR) T therapies utilize patient cells and can be limited by cell quality, and the high manufacturing burden of viral vectors. As such, there is a need for allogeneic, “off-the-shelf” CAR T cells to make these transformative treatments widely available. However, allogeneic therapies require multiple genetic engineering steps to express CAR and to delete proteins responsible for graft-versus-host disease. Messenger RNA (mRNA) is a promising approach for expression of therapeutic proteins and gene editing nucleases. In this work, we demonstrate a new method for multi-step engineering of gene-edited CAR T cells using RNA lipid nanoparticles (LNPs).

LNPs encapsulating Spy-Cas9 mRNA, TCR and CD52 guide RNA (sgRNA), and CAR mRNA were produced using microfluidics. The CAR construct contained an anti-CD19 scFv binding domain and CD3ζ/4-1BB co-stimulatory domains. Microgram quantities of RNA LNPs were produced to optimize LNP packaging, cargo ratios, and sgRNA combinations. Lead candidates were scaled to milligrams. Purified human primary T cells were cultured, activated, and expanded in serum-free media in plates, flasks and bioreactors. CAR+, TCR− or CD52− cells were generated by addition of the corresponding LNP to activated cells. Cytotoxic killing was determined by co-culture assays with leukemia cells. Gene knockout, CAR expression, viability and cell killing were measured using flow-cytometry.

CD19 CAR was selected as a relevant protein for expression, with TCR and CD52 proteins as gene knockout targets. Single-step addition of CAR LNPs to T cells resulted in transfection efficiencies of 95.0 ± 2.1% and high protein expression. Upon TCR or CD52 LNP addition to T cells, the onset of gene editing was within 48 hours, reaching single target knockout efficiencies of 92.3 ± 3.0% (TCR−), and double knockouts (TCR−/CD52−) of 74.5 ± 6.1%. Similar results were obtained when comparing different LNP batch sizes (microgram to milligram RNA) and cell culture vessels (125,000 to 45 million cells), demonstrating scalability of both the LNP production and cell treatment. Cell viabilities above 90% were maintained at all steps and for all RNA LNPs. Finally, as proof-of-concept for multi-step engineering, sequential addition of TCR LNPs and CAR LNPs resulted in simultaneous CAR expression and TCR gene knockout. These “off-the-shelf” gene-edited CAR T cells were functionally equivalent to non-edited cells in a B cell killing assay, efficiently clearing over 80% of leukemia target cells at a 1:1 ratio.

Our findings demonstrate the advantages of LNPs for RNA delivery to T cells. The simple and gentle nature of LNP cell treatment allows for multiple genetic engineering steps for simultaneous expression and deletion of proteins. Furthermore, LNPs can be easily manufactured using microfluidics, enabling small-scale screening of RNA libraries and rapid scale-up of lead candidates for clinical translation.

Citation Format: Samuel Clarke, R Geczy, A Balgi, S Park, R Zhao, M Swaminathan, R Tieu, N Hoang, C Webb, E Watt, M Wong, M Fujisawa, N Jain, Angela Zhang, Anitha Thomas. Multi-step engineering of gene-edited CAR T cells using RNA lipid nanoparticles [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1785.

Prevalence and Characterization of Salmonella Isolated from Chickens in Anhui, China

Salmonella is one of the most important zoonotic pathogens that can cause both acute and chronic illnesses in poultry flocks, and can also be transmitted to humans from infected poultry. The purpose of this study was to investigate the prevalence, antimicrobial resistance, and molecular characteristics of Salmonella isolated from diseased and clinically healthy chickens in Anhui, China. In total, 108 Salmonella isolates (5.66%) were successfully recovered from chicken samples (n = 1908), including pathological tissue (57/408, 13.97%) and cloacal swabs (51/1500, 3.40%), and S. Enteritidis (43.52%), S. Typhimurium (23.15%), and S. Pullorum (10.19%) were the three most prevalent isolates. Salmonella isolates showed high rates of resistance to penicillin (61.11%), tetracyclines (47.22% to tetracycline and 45.37% to doxycycline), and sulfonamides (48.89%), and all isolates were susceptible to imipenem and polymyxin B. In total, 43.52% isolates were multidrug-resistant and had complex antimicrobial resistance patterns. The majority of isolates harbored cat1 (77.78%), blaTEM (61.11%), and blaCMY-2 (63.89%) genes, and the antimicrobial resistance genes in the isolates were significantly positively correlated with their corresponding resistance phenotype. Salmonella isolates carry high rates of virulence genes, with some of these reaching 100% (invA, mgtC, and stn). Fifty-seven isolates (52.78%) were biofilm-producing. The 108 isolates were classified into 12 sequence types (STs), whereby ST11 (43.51%) was the most prevalent, followed by ST19 (20.37%) and ST92 (13.89%). In conclusion, Salmonella infection in chicken flocks is still serious in Anhui Province, and not only causes disease in chickens but might also pose a threat to public health security.

Liquid-like atoms in dense-packed solid glasses

Revealing the microscopic structural and dynamic pictures of glasses is a long-standing challenge for scientists^1,2. Extensive studies on the structure and relaxation dynamics of glasses have constructed the current classical picture^3-5: glasses consist of some 'soft zones' of loosely bound atoms embedded in a tightly bound atomic matrix. Recent experiments have found an additional fast process in the relaxation spectra^6-9, but the underlying physics of this process remains unclear. Here, combining extensive dynamic experiments and computer simulations, we reveal that this fast relaxation is associated with string-like diffusion of liquid-like atoms, which are inherited from the high-temperature liquids. Even at room temperature, some atoms in dense-packed metallic glasses can diffuse just as easily as they would in liquid states, with an experimentally determined viscosity as low as 10⁷ Pa·s. This finding extends our current microscopic picture of glass solids and might help establish the dynamics-property relationship of glasses⁴.

[P2X7R promotes migration and invasion of Lewis lung cancer cells by activating the AKT signaling pathway]

OBJECTIVE

To explore the role of P2X7 receptor (P2X7R) in migration and invasion of mouse Lewis lung cancer (LLC) cells and examine the tumorigenic ability of LLC cells in P2X7R-knockout mice.

METHODS

RT-PCR was used to examine P2X7R mRNA expression in LLC cells. LLC cells were treated with ATP (as a P2X7R agonist) or 2'- 3'- O- (4-benzoyl- benzoyl)-ATP (BzATP) (a P2X7R agonist) with or without pretreatment with P2X7R antagonist oxATP or A438079. The changes in migration and invasive abilities of the cells were evaluated using wound healing assay and Transwell assay; Western blotting was performed to determine the activation level of the key proteins in the AKT signaling pathway. The effects of BzATP, A438079, and LY294002 (a inhibitor of the PI3K/AKT pathway) on migration and invasion of LLC cells were also examined. In wild-type (WT) and P2X7R knockout (P2X7^-/-) C57BL/6 mice, the growth of subcutaneous LLC cell xenografts were observed by measuring tumor volume and weight.

RESULTS

P2X7R expression was detected in LLC cells. Treatment with P2X7R agonist significantly enhanced migration and invasion abilities of LLC cells, and this effect was inhibited by application of P2X7R antagonists (P < 0.001). Western blotting showed that BzATP treatment of LLC cells significantly increased the expression level of p-AKT protein, which was obviously lowered by treatment with P2X7R antagonist (P < 0.01). P2X7R antagonist strongly inhibited BzATP-induced enhancement of LLC cell migration and invasion (P < 0.001). In the tumor- bearing mice, the tumor volume and weight were significantly lower in P2X7^-/- mice than in WT mice (P < 0.05).

CONCLUSION

P2X7R promotes migration and invasion of LLC cells by activating the AKT signaling pathway, and LLC cells show lowered tumorigenic capacity in P2X7^-/- mice.