Combining mannose receptor mediated nanovaccines and gene regulated PD-L1 blockade for boosting cancer immunotherapy

Tumor nanovaccines have potential applications in the prevention and treatment of malignant tumors. However, it remains a longstanding challenge in exploiting efficient nanocarriers for inducing potent specifically cellular immune responses. Toward this objective, we herein explore an intensive tumor immunotherapeutic strategy by combining mannosylated nanovaccines and gene regulated PD-L1 blockade for immune stimulation and killing activity. Here, we fabricate a mannose modified PLL-RT (Man-PLL-RT) mediated nanovaccines with dendritic cells (DCs) targeting capacity. Man-PLL-RT is capable of co-encapsulating with antigen (ovalbumin, OVA) and adjuvant (unmethylated cytosine-phosphate-guanine, CpG) by electrostatic interaction. This positively charged Man-PLL-RT/OVA/CpG nanovaccines can facilitate the endocytosis, maturation and cross presentation in DCs. However, the nanovaccines arouse limited inhibition of tumor growth, which is mainly due to the immunosuppressed microenvironment of tumors. Combining tumor nanovaccines with gene regulated PD-L1 blockade leads to an obvious tumor remission in B16F10 melanoma bearing mice. The collaborative strategy provides essential insights to boost the benefits of tumor vaccines by regulating the checkpoint blockade with gene therapy.

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The nanovaccines are composed of polypeptides, which are bio-safe and biodegradable.

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The nanovaccines have APCs target function.

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Blocking PD-1/PD-L1 through gene therapy can reverse the tumor immune-tolerant microenvironment.

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The combined strategy provides a potentially effective strategy for the clinical treatment of tumors.

Influence Mechanism of Surfactants on Wettability of Coal with Different Metamorphic Degrees Based on Infrared Spectrum Experiments

Based on experiments, a numerical analysis is used to quantitatively explore the influence of coal and surfactant microstructures on wettability. First, based on an infrared spectrum experiment, the distribution of oxygen-containing functional groups, aromatic hydrocarbons, and aliphatic hydrocarbons of coal and surfactants was obtained. Second, the wettability relationship between coal and different surfactants was determined by optical titration, and the coal dust wettability and surfaces were optimized. The key factors of the active agent wetting ability affecting lignite wetting mainly depend on the carbonyl, ether, and carboxyl groups in the surfactant. The factors affecting non-stick coal and gas coal wetting mainly depend on the ether group and aromatic amine in the surfactant. The factors affecting fat coal wetting mainly depend on the ether group and hydroxyl group in the surfactant. Finally, the factors affecting coking coal and anthracite wetting mainly depend on the surfactant ether group, aliphatic amine, and aromatic amine. Then, combining the structural parameters with the coal wetting results, the quantitative mathematical relationship between coal dust wettability, the important influencing factors of the surfactant, and the wettability index was established. Finally, a perfect and reasonable wettability evaluation model between coal and the surfactants was established. The relative activity of methyl ether and aromatic ether is greater than that of methyl ether, and the influence on the lignite, coking coal, and anthracite wettability conforms to the model . The influence on the non-caking coal and fat coal wettability conforms to the model , while the influence on the gas coal wettability conforms to the model Z = A + B ₁ X ₁ + B ₂ X ₂. In general, this study provides scientific guidance for the compounding of high-efficiency and environmentally protective composite dust suppressors to realize clean mine production.

Effects of Tamoxifen vs. Toremifene on fatty liver development and lipid profiles in breast Cancer

BACKGROUND

Tamoxifen (TAM) and Toremifene (TOR), two kinds of selective estrogen receptor modulators (SERMs), have equal efficacy in breast cancer patients. However, TAM has been proved to affect serum lipid profiles and cause fatty liver disease. The study aimed to compare the effects of TAM and TOR on fatty liver development and lipid profiles.

METHODS

This study performed a retrospective analysis of 308 SERMs-treated early breast cancer patients who were matched 1:1 based on propensity scores. The follow-up period was 3 years. The primary outcomes were fatty liver detected by ultrasonography or computed tomography (CT), variation in fibrosis indexes, and serum lipid profiles change.

RESULTS

The cumulative incidence rate of new-onset fatty liver was higher in the TAM group than in the TOR group (113.2 vs. 67.2 per 1000 person-years, p < 0.001), and more severe fatty livers occurred in the TAM group (25.5 vs. 7.5 per 1000 person-years, p = 0.003). According to the Kaplan-Meier curves, TAM significantly increased the risk of new-onset fatty liver (25.97% vs. 17.53%, p = 0.0243) and the severe fatty liver (5.84% vs. 1.95%, p = 0.0429). TOR decreased the risk of new-onset fatty liver by 45% (hazard ratio = 0.55, p = 0.020) and showed lower fibrotic burden, independent of obesity, lipid, and liver enzyme levels. TOR increased triglycerides less than TAM, and TOR increased high-density lipoprotein cholesterol, while TAM did the opposite. No significant differences in total cholesterol and low-density lipoprotein cholesterol are observed between the two groups.

CONCLUSIONS

TAM treatment is significantly associated with more severe fatty liver disease and liver fibrosis, while TOR is associated with an overall improvement in lipid profiles, which supports continuous monitoring of liver imaging and serum lipid levels during SERM treatment.

Comparison of glycation degrees of HbG-Coushatta and HbG-Taipei with HbA using liquid chromatography with tandem mass spectrometry

BACKGROUND

Hemoglobin A_1c(HbA_1c) is widely used to measure glycemic status and control in diabetes testing and treatment and is an important risk factor forcomplications of diabetes. Hemoglobin variants can interfere with the HbA_1c testing method by reducing the life span of erythrocytes or due to differences in glycation degrees. In this study, glycation levels of the HbA, HbG-Coushatta, and HbG-Taipei β-chains (βA, βG-Coushatta, and βG-Taipei, respectively) were examined.

METHODS

Blood samples from heterozygotic patients (HbG-Coushatta/HbA, HbG-Taipei/HbA) were analyzed. Glycation rateswere determined using high-performance liquid chromatography with tandem mass spectrometry. Ratios of glycated βG-Coushatta to glycated βA and glycated βG-Taipei to glycated βA were calculated by comparingareas under the curves from extracted ion chromatograms.

RESULTS

βG-Coushatta and βG-Taipei were 6.08 ± 1.38% and 5.95 ± 0.93% glycated (respectively), which were significantly higher than βA chains(4.55 ± 1.30% and 4.51 ± 0.91%, respectively; p = 0.000). The total glycation degree (α + β) in HbG-Coushatta and HbG-Taipei heterozygotes were estimated to be 9% and 8% higher than those of HbA homozygotes (P＜0.001), respectively.

CONCLUSION

βG-Coushatta and βG-Taipei glycation degrees were significantly higher than βA, while the differences in total hemoglobin (α + β) were small and unlikely to impact the clinical interpretation of HbA_1c results.

Efficacy and Safety of Leflunomide for Refractory COVID-19: A Pilot Study

Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may persist in patients with coronavirus disease 2019 (COVID-19) despite receiving standard care.

Methods: In this pilot study of hospitalized adult patients (≥18 years of age), with radiologically confirmed pneumonia who were SARS-CoV-2 positive for more than 28 days despite standard care, were assigned to receive standard of care (SOC, grp I) or leflunomide + SOC (grp 2). After 2 weeks, grp 1 and grp 2 patients who continued to be SARS-CoV-2-positive received leflunomide for 14 days while continuing SOC. The primary outcomes were the rate of and time to SARS-CoV-2 clearance and the 14-day and 30-day hospital discharge rate.

Results: 12 patients were enrolled in grp 1 and 15 patients were in grp 2. The 14 days SARS-CoV-2 viral clearance rate was 80.0% (12/15) for grp 2 patients receiving leflunomide vs. 16.7% for grp 1 patients (2/12) (p = 0.002). By day 14, the median time to SARS-CoV-2 clearance was 6.0 days (range 1–12, IQR 1–12) for grp 2 patients. In grp 1, two patients converted to viral negative on days 1 and 6 (p = 0.002). The 14-day discharge rate was 73.3% (11/15) for the grp 2 vs. 8.3% (1/12) for grp 1 (p = 0.001). The 30 days discharge rate was 100% (15/15) for the grp 2 vs. 66.7% (8/12) for grp 1. No severe adverse events or deaths were reported.

Conclusion: Leflunomide may improve the SARS-CoV-2 clearance rate and discharge rate in patients with refractory COVID-19. The tolerability of the 14–28 days course of treatment with leflunomide is acceptable. These preliminary observations need to be verified by a large sample size and randomized controlled trial.

CCT5 interacts with cyclin D1 promoting lung adenocarcinoma cell migration and invasion

Cyclin D1 (CCND1) has been identified as a metastatic promoter in various tumors including lung adenocarcinoma (LUAD), a subtype of non small cell lung cancer (NSCLC). The previous observation revealed that CCND1 was upregulated in NSCLC and predicted poor prognosis of LUAD patients. In this study, we examined a chaperonin containing TCP1 subunit 5 (CCT5) protein interacts with CCND1 in LUAD. Immunofluorescence demonstrated the co-localization of CCT5 and CCND1 protein in LUAD cells. CCT5 expression was detected with both immunohistochemistry (IHC) and bioinformatics analyses. Similar with the expression pattern of CCND1, CCT5 displayed a high level in LUAD tissues compared to non cancerous lung specimens. Patients with high CCT5 expression showed a significant shorter overall survival relative to those with low expression level. Furthermore, upregulated CCT5 exhibited significant positive correlation with TNM stage of LUAD patients in both IHC analyses and bioinformatics. Knocking down CCT5 remarkably inhibited LUAD cell migration and invasion in vitro by inactivating PI3K/AKT and its downstream EMT signals, which could abrogated the accelerated migration and invasion caused by CCND1 overexpression. In summary, our study discovered a highly expressed protein CCT5 in LUAD which interacted with CCND1 and promoted migration and invasion of LUAD cells by positively moderating PI3K/AKT-induced EMT pathway.

Depressive State in the Emergency Department During COVID-19: A National Cross-Sectional Survey in China

Chinese emergency department (ED) staff encountered significant mental stress while fighting the coronavirus disease 2019 (COVID-19) pandemic. We sought to investigate the prevalence and associated factors for depressive symptoms among ED staff (including physicians, nurses, allied health, and auxiliary ED staff). A cross-sectional national survey of ED staff who were on duty and participated in combating the COVID-19 pandemic was conducted March 1-15, 2020. A total of 6,588 emergency medical personnel from 1,060 hospitals responded to this survey. A majority of respondents scored above 10 points on the PHQ-9 standardized test, which is associated with depressive symptoms. Those aged 31-45, those working in the COVID-19 isolation unit, and those with relatives ≤ 16 or ≥70 years old at home all had statistically significant associations with scoring >10 points. Depressive symptoms among Chinese emergency medical staff were likely quite common during the response to the COVID-19 pandemic and reinforce the importance of targeted ED staff support during future outbreaks.

Identify Function of WASL in Prognosis of Cervical Cancer Based on Omics Data

Objective

To clarify the clinical relevance of WASP like actin nucleation promoting factor (WASL) in patients with cervical cancer and associated mechanisms.

Methods and Materials

We obtained high prediction accuracy and determined the correlation between the expression of WASL and the clinical characteristics of cervical cancer patients. Differentially expressed genes (DEGs) were identified using microarray. Gene ontology (GO) enrichment analysis and gene set enrichment analysis (GSEA) were performed to determine potentially relevant mechanisms related to the prognostication ability of WASL expression.

Results

Chi-square test and multivariable logistic regression analysis suggested that lower expression of WASL was associated with lower pathological stage (chi-square test: p = 0.022, chi-square = 9.613; logistic regression: OR = 0.869, 95% CI: 0.756-0.991, p = 0.041). Patients in the WASL high expression group have worse overall survival (OS) [hazard ratio (HR): 0.555, 95% CI: 0.348-0.884, log-rank p = 0.012] and recurrence-free survival (RFS) (HR = 0.449, 95% CI: 0.215-0.934, log-rank p = 0.028) compared with those in the WASL low expression group. Univariate and multivariable Cox proportional hazards regression model suggested that WASL expression was an independent prognostic factor for predicting OS and RFS in cervical cancer. DEGs were mostly enriched GO terms related to DNA replication or the proliferation of tumor cells. The results of GSEA suggested samples in the WASL knockdown group were enriched in glycolysis, TNF-α signaling via NFkB, mTORC1 signaling, and Wnt/β-catenin signaling.

Conclusions

WASL expression was associated with the pathological stage, and it might be an independent prognostication factor in patients with cervical cancer. Knockdown of WASL might be correlated with biological processes such as glycolysis, TNFα signaling, mTOR signaling, and Wnt/β-catenin signaling.

Consideration triggered by the choice of heterophilic antibody interference detection tests in measuring ACTH for a teenager boy with a rare adrenal disease

BACKGROUND

Plasma ACTH is an important marker for Cushing syndrome; inaccurate measurement of ACTH concentrations due to the serum heterophile antibody may mislead diagnosis by physicians. We describe the case of a teenage boy with a rare adrenal disease who presented falsely increased ACTH concentrations (20.3 pg/ml; Siemens Immulite).

METHODS

Low dose dexamethasone inhibition test showed no inhibition of serum cortisol. While biochemical evidence suggested ACTH-dependent Cushing, the imaging tests suggested otherwise. Hence, further tests for interference identification, including test platform replacement, sample dilution, PEG precipitation, and use of blocking antibodies, were conducted.

RESULTS

The measurements of the same patient sample on three different analytical platforms suggested ACTH concentrations below 5 pg/ml. Serial dilutions of serum samples revealed nonlinearity, PEG recovery resulted in ACTH concentrations dropping to < 5 pg/ml, and interferences in plasma were blocked by a heterophilic blocking reagent (21.2 vs < 5 pg/ml), suggesting that assay interference performed on Siemens Immulite led to false-positive ACTH. Finally, the boy was diagnosed with a rare type of ACTH-independent Cushing syndrome.

CONCLUSIONS

The inaccurate evaluation of ACTH misled the physicians, increasing treatment time and diagnostic testing. Thus, an anti-interference workflow should be established between physicians and laboratories to avoid such cases in the future.

Prodrug-Based Versatile Nanomedicine with Simultaneous Physical and Physiological Tumor Penetration for Enhanced Cancer Chemo-Immunotherapy

Chemo-immunotherapy combination effect remains to be a great challenge due to the poor tumor penetration of therapeutic agents that resulted from condensed extracellular matrix (ECM), T cell-related immune escape, and thus the potential recurrence. Herein, a helix self-assembly camptothecin (CPT) prodrug with simultaneous physical and physiological tumor penetration was constructed to realize effective chemo-immunotherapy. Specifically, CPT was modified with arginine to self-assemble into nanofibers to physically improve tumor penetration. Two plasmids, pshPD-L1 and pSpam1 for expressing small hairpin RNA PD-L1 and hyaluronidase, respectively, were loaded to down-regulate tumor surface PD-L1 expression for converting anergic state of T cells into the tumor-reactive T cells and produce hyaluronidase to physiologically degrade ECM for further enhanced tumor penetration. Moreover, the degraded ECM could also increase immune cells' infiltration into tumor sites, which may exert a synergistic antitumor immunity combined with immune checkpoint inhibition. Such a nanomedicine could cause significant inhibition of primary, distant tumors, and effective prevention of tumor recurrence.

Dual-emission ratio fluorescence for selective and sensitive detection of ferric ions and ascorbic acid based on one-pot synthesis of glutathione protected gold nanoclusters

A fluorometric method was proposed for the determination of Fe³⁺ and ascorbic acid (AA) based on blue and red dual fluorescence emissions of glutathione (GSH) stabilized-gold nanoclusters (AuNCs). AuNCs were synthesized from GSH and tetrachloroauric acid. The fluorescence peaks of AuNCs were at 425 nm and 585 nm, respectively. In the presence of Fe³⁺, the fluorescence peak at 425 nm can be enhanced and that at 585 nm can be quenched. There is a good linear relationship between the fluorescence intensity ratio for the 425 and 585 nm peaks (F ₄₂₅/F ₅₈₅) and the concentration of Fe³⁺ in the range of 0.75-125 μM. However, when AA was added to the AuNCs-Fe³⁺ system, the value of F ₄₂₅/F ₅₈₅ decreased consistently with the concentration of AA in the range of 0.25-35 μM. The limit of detection for Fe³⁺ and AA was 227 and 75.8 nM, respectively. The interaction between AuNCs and Fe³⁺ can induce the ligand-metal charge transfer (LMCT) effect leading to the fluorescence increment at 425 nm, while AA can reduce Fe³⁺ to Fe²⁺. The production of Fe²⁺ can not enhance or quench the fluorescence of AuNCs. By comparison with previous literature, the AuNCs prepared here show two fluorescence peaks without additional fluorescence labels. Furthermore, the method was successfully applied in the determination of Fe³⁺ and AA in some real samples, such as water, human serum and tablets.

Sarcopenia in Patients With Normal Body Mass Index Is an Independent Predictor for Postoperative Complication and Long-Term Survival in Gastric Cancer

Malnutrition in patients with gastric cancer (GC) with normal body mass index (BMI) is often ignored. This study aimed to explore the role of sarcopenia in predicting postoperative complication and long-term survival in patients with GC with normal BMI. We included patients with normal BMI (18.5 kg/m²  ≤ BMI < 23 kg/m² ) who underwent radical gastrectomy between July 2014 and December 2016. Sarcopenia was assessed by muscle mass, handgrip strength, and gait speed. Kaplan-Meier survival analysis was used to analyze the association between sarcopenia and the prognosis of patients with GC. Univariate and multivariate analyses were used to identify risk factors contributing to postoperative complications and long-term survival. Overall, 267 patients with GC with normal BMI were included in this study; of which 49 (18.35%) patients were diagnosed with sarcopenia. Patients with sarcopenia had higher incidence of a major postoperative complication, longer postoperative hospital stays, and greater hospital costs. The Kaplan-Meier survival analysis showed that patients with sarcopenia had poorer overall survival than non-sarcopenia patients. Univariate and multivariate analyses showed that sarcopenia was an independent predictor for postoperative complication and long-term survival in such patients. Sarcopenia is an independent predictor for postoperative complications and long-term survival in patients with normal BMI after radical gastrectomy for GC. We recommend that patients with normal BMI should perform nutritional risk screening by sarcopenia.

Cationic Flexible Organic Framework for Combination of Photodynamic Therapy and Genetic Immunotherapy Against Tumors

Photodynamic therapy is a new type of anti-tumor therapy with excellent therapeutic effects and minor side effects. The key factor for photodynamic therapy is highly efficient loading and protection of photosensitizers. Covalent organic framework is a new type of organic porous material with rich sources and has huge development potential in the loading of photosensitizers. However, the π-π interaction between the rigid monomers inevitably causes aggregation and quenching between photosensitizers, which in turn affects the rate of reactive oxygen production. Here, newly designed cationic flexible organic framework nanoparticles (PEI-Por NPs) are synthesized via one-step method with PEI25K and meso-tetra(p-formylphenyl)porphyrin under microwave irradiation. The structure of the flexible organic framework can effectively inhibit the aggregation and quenching of porphyrin. In addition, PEI-Por NPs had excellent gene transfection ability both in vitro and in vivo. Excellent antitumor effect can be achieved by combining PEI-Por NPs' photodynamic therapy capacity and PEI-Por NPs-mediated PD-L1 gene silencing with the guidance of fluorescence imaging and photoacoustic imaging. This cationic flexible organic framework material combines the advantages of flexible building units and rigid monomers, which provides a basis for the development of nano-photosensitizers and excellent gene carriers, and has great potential for clinical application.

Characteristics of Infiltrating Immune Cells and a Predictive Immune Model for Cervical Cancer

The role of infiltrating immune cells within the tumor microenvironment has received considerable attention, but their function in cervical cancer remains to be elucidated; thus, comprehensive evaluation of their predictive value is needed. Using cervical cancer samples from 406 patients, immune cell infiltration was evaluated via immunohistochemistry. CD3+, CD4+, CD8+, CD20+, CD57+, CD68+, and CD163+ cell infiltration was compared in samples from adjacent tissues and the tumor center. The associations between immune cell distributions in the tumor center, clinicopathological features, and prognosis were correlated among immune cell types. Using three immune features, an immune model was constructed based on a Cox regression analysis with the least absolute shrinkage and selection operator (lasso) penalty to derive immune risk scores.

Immune cells that infiltrated the tumor center correlated with clinicopathological characteristics and prognosis. The immune risk scores were an independent prognostic indicator and were found to predict cervical cancer prognosis as well as the effects of chemoradiotherapy. We classified patients into either high- or low-risk subgroups (namely CD4+^highCD163+^highCD57+^low and CD4+^lowCD163+^lowCD57+^high, respectively) based on their immune scores. Significant differences were found in the 3-year overall survival of patients with high- and low-risk scores (83.0% vs. 96.6%; P < 0.001). High immune risk scores resulted in decreased overall survival for patients in stages IB1+IIA1, IB2+IIA2, and IIB-IV (P = 0.001, P = 0.008, and P = 0.044, respectively). Overall survival was significantly worse following chemoradiotherapy in high-scoring patients in stages IB1+IIA1 and IB2+IIA2 (P = 0.001 and P=0.008, respectively). Moreover, overall survival was significantly worse after radiotherapy or chemotherapy in high-scoring patients in stage IB1+IIA1 (P = 0.03). Our work reveals that the distribution of infiltrating immune cells affects their function in cervical cancer. Our tumor center-centric immune model effectively predicted survival, suggesting its potential use in identifying suitable candidates for chemoradiotherapy.

Cell competition constitutes a barrier for interspecies chimerism

Cell competition involves a conserved fitness-sensing process during which fitter cells eliminate neighbouring less-fit but viable cells1. Cell competition has been proposed as a surveillance mechanism to ensure normal development and tissue homeostasis, and has also been suggested to act as a barrier to interspecies chimerism2. However, cell competition has not been studied in an interspecies context during early development owing to the lack of an in vitro model. Here we developed an interspecies pluripotent stem cell (PSC) co-culture strategy and uncovered a previously unknown mode of cell competition between species. Interspecies competition between PSCs occurred in primed but not naive pluripotent cells, and between evolutionarily distant species. By comparative transcriptome analysis, we found that genes related to the NF-κB signalling pathway, among others, were upregulated in less-fit 'loser' human cells. Genetic inactivation of a core component (P65, also known as RELA) and an upstream regulator (MYD88) of the NF-κB complex in human cells could overcome the competition between human and mouse PSCs, thereby improving the survival and chimerism of human cells in early mouse embryos. These insights into cell competition pave the way for the study of evolutionarily conserved mechanisms that underlie competitive cell interactions during early mammalian development. Suppression of interspecies PSC competition may facilitate the generation of human tissues in animals.

Clinical characteristics, cause analysis and infectivity of COVID-19 nucleic acid repositive patients: A literature review

Coronavirus disease 2019 (COVID-19) poses a serious threat to human health and lives. The virus is still spreading throughout the world, and the cumulative number of confirmed cases is increasing. After patients with COVID-19 are treated and discharged, some have repeated clinical symptoms and become positive for nucleic acid tests a second time. Through analysis and review of the existing literature, the proportion of repositive patients in the discharged patient population and their clinical characteristics were systematically described for the first time. Furthermore, an in-depth analysis of the causes of repositive nucleic acid tests and the potential transmission of the disease provides the basis for the management and protection of discharged patients with COVID-19.

Cross-species single-cell transcriptomic analysis reveals pre-gastrulation developmental differences among pigs, monkeys, and humans

Interspecies blastocyst complementation enables organ-specific enrichment of xenogeneic pluripotent stem cell (PSC) derivatives, which raises an intriguing possibility to generate functional human tissues/organs in an animal host. However, differences in embryo development between human and host species may constitute the barrier for efficient chimera formation. Here, to understand these differences we constructed a complete single-cell landscape of early embryonic development of pig, which is considered one of the best host species for human organ generation, and systematically compared its epiblast development with that of human and monkey. Our results identified a developmental coordinate of pluripotency spectrum among pigs, humans and monkeys, and revealed species-specific differences in: (1) pluripotency progression; (2) metabolic transition; (3) epigenetic and transcriptional regulations of pluripotency; (4) cell surface proteins; and (5) trophectoderm development. These differences may prevent proper recognition and communication between donor human cells and host pig embryos, resulting in low integration and survival of human cells. These results offer new insights into evolutionary conserved and divergent processes during mammalian development and may be helpful for developing effective strategies to overcome low human-pig chimerism, thereby enabling the generation of functional human organs in pigs in the future.

Construction of a ratio fluorescence assay of 5-aminosalicylic acid based on its aggregation induced emission with blue emitting N/P-codoped carbon dots

Herein, a novel ratio fluorescence method based on N/P-doped carbon dots (NPCDs) for detecting 5-aminosalicylic acid (5-ASA) in mesalazine enteric coated tablets and blood were reported for the first time. NPCDs were successfully prepared through a simple one-step hydrothermal strategy by employing adenosine triphosphate (ATP) and p-toluidine as raw materials. NPCDs exhibit bright blue emissions with excitation/emission peaks at 340/423 nm with moderate quantum yield (20.75%). In addition, 5-ASA has a certain weak fluorescence emission peak at 487 nm. Adding 5-ASA into NPCDs significantly enhanced the fluorescence intensity, which may result from aggregation induced emission (AIE) of 5-ASA on the surface of NPCDs. Therefore, NPCDs only provide self-calibration signals, and their fluorescence remains almost unchanged when co-existing with 5-ASA. Therefore, the ratio of fluorescence at F₄₈₇/F₄₂₃ was used for detection of 5-ASA. For the fluorometric determination assay, there was a good linear relationship between F₄₈₇/F₄₂₃ and 5-ASA concentration between 0.50 and 130 μM (R² = 0.9979). The detection limit was about 0.13 μM. Therefore, this method is simple, sensitive and low cost, and will be successfully applied to the detection of 5-ASA in drugs.

Herein, a novel ratio fluorescence method based on N/P-doped carbon dots (NPCDs) for detecting 5-aminosalicylic acid (5-ASA) in mesalazine enteric coated tablets and blood were reported for the first time.

Preparation and photocatalytic performance of silver-modified and nitrogen-doped TiO2 nanomaterials with oxygen vacancies

A modified hydrothermal method for the synthesis of TiO₂ material to achieve a more efficient visible light response.