Engineering mesoporous polydopamine-based potentiate STING pathway activation for advanced anti-biofilm therapy.

The biofilm-induced "relatively immune-compromised zone" creates an immunosuppressive microenvironment that is a significant contributor to refractory infections in orthopedic endophytes. Consequently, the manipulation of immune cells to co-inhibit or co-activate signaling represents a crucial strategy for the management of biofilm. This study reports the incorporation of Mn2+ into mesoporous dopamine nanoparticles (Mnp) containing the stimulator of interferon genes (STING) pathway activator cGAMP (Mncp), and outer wrapping by M1-like macrophage cell membrane (m-Mncp). The cell membrane enhances the material's targeting ability for biofilm, allowing it to accumulate locally at the infectious focus. Furthermore, m-Mncp mechanically disrupts the biofilm through photothermal therapy and induces antigen exposure through photodynamic therapy-generated reactive oxygen species (ROS). Importantly, the modulation of immunosuppression and immune activation results in the augmentation of antigen-presenting cells (APCs) and the commencement of antigen presentation, thereby inducing biofilm-specific humoral immunity and memory responses. Additionally, this approach effectively suppresses the activation of myeloid-derived suppressor cells (MDSCs) while simultaneously boosting the activity of T cells. Our study showcases the efficacy of utilizing m-Mncp immunotherapy in conjunction with photothermal and photodynamic therapy to effectively mitigate residual and recurrent infections following the extraction of infected implants. As such, this research presents a viable alternative to traditional antibiotic treatments for biofilm that are challenging to manage.

The activation of asparagine synthetase by the transcription factor FOXM1 plays a pivotal role in the initiation and progression of ESCC.

This study explores the role of the transcription factor FOXM1 in the initiation and progression of oesophageal squamous cell carcinoma (ESCC). Our findings reveal that FOXM1 is highly expressed in ESCC and correlates with the prognosis of the disease. The relationship between FOXM1 and asparagine synthetase (ASNS) is investigated, and the study demonstrates that FOXM1 activates ASNS, impacting the tumour stemness of ESCC. In this study, we reveal the association between FOXM1 and ESCC development, as well as FOXM1's promotion of migration and proliferation in ESCC cells. The study also highlights FOXM1's regulation of ASNS transcription and the functional role of ASNS in ESCC metastasis and growth. Furthermore, the study explores the impact of FOXM1 and ASNS on ESCC stemness and their potential implications for chemotherapy resistance.

Deteriorating wintertime habitat conditions for waterfowls in Caizi Lake, China: Drivers and adaptive measures.

China has made enormous strides to achieve high-quality development and biodiversity conservation, and the establishment of nature-protected areas is one of the essential initiatives. Caizi Lake involves a natural reserve and two national wetland parks, accommodating winter migratory waterfowl over the middle and lower Yangtze River basin in China. However, the water transfer from the Yangtze River to the Huai River (YR-HR water transfer) has modified the winter hydrological conditions of Caizi Lake, negatively affecting wintertime waterfowl habitats. Hence, conserving wintertime waterfowl habitats necessitates knowledge of the dynamical mechanisms behind the impacts of YR-HR water transfer on wintertime waterfowl habitats and adaptive measures. Here we developed a machine learning model, the normalized difference vegetation index, and on-spot observatory datasets such as the spatial distribution of waterfowl species and underwater topography of Caizi Lake. We found that the rising winter water level of Caizi Lake encroaches on winter waterfowl habitat with extremely high suitability. Meanwhile, rising water levels reduced waterfowl food sources. Thus, rising water levels due to YR-HR water transfer deteriorated waterfowl living conditions over Caizi Lake. Therefore, we proposed adaptive measures to alleviate these negative effects, such as water level regulation, artificial feeding of waterfowls, restoration and reconstruction of contiguous mudflats, grass flats. This study highlights human interferences with waterfowl habitats, necessitating biodiversity conservation at regional scales.

A novel dialdehyde cellulose-based colorimetric and turn-on fluorescent probe for H2S detection and its application in red wine.

Hydrogen sulfide (H2S) is considered one of the most important gaseous transmitters in the metabolic system, and the abnormal concentration of H2S is associated with a variety of diseases. Up to now, it is still a challenge to develop a portable assay for H2S even though the research about the detection of H2S is booming. Herein, a novel bifunctional dialdehyde-cellulose fluorescent probe DAC-DPD was prepared with high selectivity and sensitivity to H2S with colorimetric and fluorescent "turn-on" characteristics, and the limit of detection (LOD) of DAC-DPD for H2S was 0.831 µM. The sensing mechanism of DAC-DPD's to H2S was a Michael addition reaction confirmed by HRMS, 1H NMR and density-functional theory (DFT) calculations. DAC-DPD can be used to detect H2S in red wine samples. In Addition, the prepared DAC-DPD embedded fluorescent membrane can be used as a reliable sensing platform for rapid detection of H2S. It provided a convenient and rapid detection material, simplifying the detection process of H2S, which is of great significance for the development of cellulose-based fluorescent smart material.

Design of a Membrane-Anchored DNAzyme-Based Molecular Machine for Enhanced Cancer Therapy by Customized Cascade Regulation.

Synthetic DNAzyme-based structures enable dynamic cell regulation. However, engineering an effective and targeted DNAzyme-based structure to perform customizable multistep regulation remains largely unexplored. Herein, we designed a membrane-anchored DNAzyme-based molecular machine to implement dynamic inter- and intracellular cascade regulation, which realizes efficient T-cell/cancer cell interactions and subsequent receptor mediated cancer cell uptake. Using CD8+ T-cells and HeLa cancer cells as a proof of concept, we demonstrate that the designed DNAzyme-based molecular machine enables customized cascade regulation including (1) specific recognition between T-cells and cancer cells, (2) specific response and fluorescence sensing upon extracellular stimuli, and (3) cascade regulation including intercellular distance shortening, cell-cell communication, and intracellular delivery of anticancer drugs. Together, this work provides a promising pathway for customized cascade cell regulation based on a DNAzyme-based molecular machine, which enables enhanced cancer therapy by combining T-cell immunotherapy and chemotherapy.

Huopuxialing Decoction: A Promising Candidate for Precancerous Lesions of Gastric Cancer Treatment Based on Bioinformatics and Experimental Verification.

BACKGROUND: The Precancerous Lesion of Gastric Cancer (PLGC) is an early stage in the development of gastric cancer. The clinical application of HPXLD has been found to be effective in treating PLGC, but the mechanism of how HPXLD acts on PLGC is still unclear. OBJECTIVE: The objectives of this study were to reveal the molecular mechanism of how HPXLD can be used to treat PLGC and investigate this mechanism through bioinformatics and experimental validation. METHODS: PLGC-associated target genes were identified through bioinformatics analysis. A rat model of PLGC was induced using N-methyl-N'-nitro-N-nitrosoquanidine (MNNG) in combination with ranitidine, hot saline, ethanol, and intermittent fasting, with interventions by HPXLD. The pathological alterations in gastric mucosa were assessed through Hematoxylin-eosin staining (HE). Immunohistochemistry (IHC) and Western blot analyses were employed to evaluate the changes in expression levels of inflammation-related proteins. RESULTS: After conducting bioinformatics analysis, it was found that there were 23 HPXLDPLGC crossover genes, which were significantly enriched in the IL-17 signaling pathway, TNF signaling pathway, and NF-kappa B signaling pathway. The results of HE showed that HPXLD was effective in improving gastric mucosal histopathological changes. Additionally, the IHC results demonstrated that HPXLD was able to downregulate the expression of IL-6, COX-2, MCP- 1, and MMP-9. Furthermore, Western blot analysis revealed that HPXLD was able to downregulate the expressions of IL-6, IL-17RA, ACT1, NF-κB, and TNF-α. CONCLUSION: HPXLD has been shown to improve PLGC by reducing the expression of inflammation- related proteins. This suggests that HPXLD may potentially be a treatment option for PLGC.

Characterization of a secondary palmitoleoyltransferase of lipid A in Vibrio parahaemolyticus.

The detection of pathogenicity and immunogenicity in Vibrio parahaemolyticus poses a significant challenge due to its threat to human health and food safety, which is strongly correlated with lipid A. Lipid A, a critical component found in most Gram-negative bacteria, functions as a hydrophobic anchor for lipopolysaccharide. V. parahaemolyticus synthesizes multiple lipid A species with various secondary acyl chains. In this study, a secondary acyltransferase of lipid A encoded by VP_RS08405 in V. parahaemolyticus was identified. Based on sequence alignment analysis, V. parahaemolyticus VP_RS08405 has high homology to E. coli lpxL, lpxM and lpxP which encode the three secondary acyltransferases of lipid A. Therefore, V. parahaemolyticus VP_RS08405 was cloned into pBAD33, and the resulting pB08405 was introduced in E. coli mutants WHL00 in which lpxL was deleted, WHM00 in which lpxM was deleted, WHP00 in which lpxP was deleted, and WH300 in which lpxL, lpxM and lpxP were deleted. The recombinant strains WHL00/pB08405, WHM00/pB08405, WHP00/pB08405, WH300/pB08405, as well as their vector controls, were grown at normal and low temperatures. Lipid A species were isolated from the above strains and analyzed by using high-performance liquid chromatography-tandem mass spectrometry and thin-layer chromatography. After comparing the secondary acyl alterations of lipid A from different recombinant strains, it is concluded that VP_RS08405 specifically catalyzed the addition of a palmitoleate to the 2'-position of lipid A and its activity is not temperature-sensitive. In addition, to determine the dependence of VP_RS08405 on Kdo, VP_RS08405 was overexpressed in E. coli mutants WH001 in which waaA was deleted, and WH400 in which waaA, lpxL, lpxM and lpxP were deleted. Lipid A species were isolated from WH001/pB08405 and WH400/pB08405, and analyzed. The results show that the function of VP_RS08405 is Kdo-dependent. These findings provide a better understanding of the structural diversity of lipid A in V. parahaemolyticus.

Perfluorooctanoic acid (PFOA) and its alternative perfluorobutanoic acid (PFBA) alter hepatic bile acid profiles via different pathways.

The disruption of per- and polyfluoroalkyl substances (PFASs) on bile acid (BA) homeostasis has raised public concerns, making the evaluation of their effects and underlying mechanisms a high priority. Although the use of perfluorooctanoic acid (PFOA) has been restricted, it remains a widespread legacy PFAS in the environment. Concurrently, the use of its prevalent short-chain alternative, perfluorobutanoic acid (PFBA), is increasing, yet the toxicity assessment of PFBA remains inadequate. In this study, C57BL/6N mice were exposed to PFOA and PFBA (0.4 or 10 mg/kg body weight) by gavage for 28 days. The results showed that both PFOA and PFBA significantly increased hepatic weight, although PFBA exhibited lower bioaccumulation than PFOA in the liver. Targeted metabolomics revealed that PFOA significantly decreased total BA levels and altered their composition. Conversely, PFBA, without significantly altering total BA levels, notably changed their composition, such as increasing the proportion of cholic acid. Further investigations using in vivo and in vitro assays suggested that PFOA inhibited the expression of Cyp7A1, a key BA synthetase, potentially via PPARα activation, thereby reducing BA levels. In contrast, PFBA enhanced Cyp7A1 expression, associated with the inhibition of intestinal Farnesoid X receptor-fibroblast growth factor 15 (FXR-FGF15) pathway. This study evaluated the differences in the BA-interfering effects of PFOA and PFBA and shed light on the potential mechanisms, which will provide new insights into the health risks of legacy PFASs and their alternatives.

Spatial Mapping of Bioactive Metabolites in the Roots of Three Bupleurum Species by Matrix-Assisted Laser Desorption/Ionization Mass Spectrometry Imaging.

Bupleurum is a kind of medicinal plant that has made a great contribution to human health because of the presence of bioactive metabolites: Bupleurum saikosaponins and flavonoids. Despite their importance, it has been a challenge to visually characterize the spatial distribution of these metabolites in situ within the plant tissue, which is essential for assessing the quality of Bupleurum. The development of a new technology to identify and evaluate the quality of medicinal plants is therefore necessary. Here, the spatial distribution and quality characteristics of metabolites of three Bupleurum species: Bupleurum smithii (BS), Bupleurum marginatum var. stenophyllum (BM), and Bupleurum chinense (BC) were characterized by Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Twenty-nine metabolites, including saikosaponins, non-saikosaponins, and compounds from the saikosaponin synthesis pathway, were characterized. Some of these were successfully localized and visualized in the transverse section of roots. In these Bupleurum species, twelve saikosaponins, five non-saikosaponins, and five saikosaponin synthesis pathway compounds were detected. Twenty-two major influencing components, which exhibit higher ion intensities in higher quality samples, were identified as potential quality markers of Bupleurum. The final outcome indicates that BC has superior quality compared to BS and BM. MALDI-MSI has effectively distinguished the quality of these Bupleurum species, providing an intuitive and effective marker for the quality control of medicinal plants.

Green electrospun Fe-based MOFs incorporated polyvinyl alcohol/carboxymethyl chitosan nanofibrous membranes for enhanced adsorption of tetracycline hydrochloride.

Tetracycline hydrochloride (TCH) removal from wastewater has drawn much attention recently, although it still remains challenging. Herein, Fe-based metal-organic frameworks (MOFs) incorporated nanofibrous membranes were prepared by green electrospinning and applied as adsorbents to remove TCH. The presence of MOFs noticeably improved specific surface area of the nanofibrous membranes, and adsorption capability increased with the amount of MOFs within membranes. As the temperature increased, the amount of TCH that was adsorbed continuously reduced, and the maximum adsorption capacity (248.5 mg/g) was attained at 273 K. The adsorption behavior of the nanofibrous membranes followed Langmuir isotherm model and pseudo-second-order kinetic model. Thermodynamic parameters suggested that the adsorption process was spontaneous and exothermic. A series of interactions between the membrane and TCH, such as pore filling, coordination bonding, π-π interaction, hydrogen bonding interaction and electrostatic interaction, combined to enhance the adsorption performance. Good stability and adsorption capability were demonstrated by the nanofibrous membranes, suggesting that they could be used for effective and affordable water purification.

Advanced glycation end products (AGEs) impair the intestinal epithelial barrier via STAT3 activation mediated by macrophages.

Advanced glycation end products (AGEs) are a spectrum of complex compounds widely found in processed foods and frequently consumed by humans. AGEs are implicated in impairing the intestinal barrier, but the underlying mechanisms remain unclear. This study investigated the effects of three types of AGEs on gene expression of tight junctions (TJs) in colorectal epithelial HT-29 cells, and observed minimal alterations in TJs expression. Given the important role of subepithelial macrophages in regulating the intestinal barrier, we explored whether AGEs affect the intestinal barrier via the involvement of macrophages. Notably, a significant downregulation of TJs expression was observed when supernatants from AGEs-treated RAW264.7 macrophage cells were transferred to HT-29 cells. Further investigations indicated that AGEs increased IL-6 levels in RAW264.7 cells, subsequently triggering STAT3 activation and suppressing TJs expression in HT-29 cells. The role of STAT3 activation was confirmed by observing enhanced TJs expression in HT-29 cells following pretreatment with an inhibitor of STAT3 activation prior to the transfer of the conditioned medium. These findings demonstrated that AGEs impaired the intestinal barrier via macrophage-mediated STAT3 activation, shedding light on the mechanisms underlying AGEs-induced intestinal barrier injury and related food safety risks.

Optimizing commercial Arabica coffee quality by integrating flavor precursors with anaerobic germination strategy.

This study attempted to improve commercial Arabica coffee quality by integrating flavor precursors with anaerobic germination. Using raw coffee beans as materials, anaerobic germination was conducted with 5 g/100 g of flavor precursors (sucrose, glucose, fructose). The chemical composition and sensory quality of roasted coffee beans were analyzed. Results showed that adding flavor precursors facilitated the harmonization of water-soluble chemical components and altered aroma characteristics. Specifically, the inclusion of flavor precursors significantly increased the levels of 5-Hydroxymethylfurfural and volatile aldehydes. Principal component analysis (PCA) on chemical composition dataset revealed 48.7% variability. Sensory analysis, employing the Specialty Coffee Association (SCA) cupping protocol, demonstrated that combining flavor precursors with anaerobic germination transformed coffee flavor properties, enhanced quality, and substantially increased sensory scores (p < 0.05). Sucrose supplementation produced the highest sensory score and intensified fruity flavor attributes. Therefore, adding different flavor precursors forms distinct flavor characteristics, conducive to further improving the quality of germinated coffee.

Breastfeeding may reduce the effects of maternal smoking on lung cancer mortality in adult offspring: a prospective cohort study.

BACKGROUND: Although previous research has indicated a correlation between smoking and the mortality rate in patients with lung cancer, the impact of early life factors on this relationship remains unclear and requires further investigation. This study aimed to investigate the hypothesis that breastfeeding reduces the risk of lung cancer-related death. METHODS: The authors conducted a prospective cohort study involving 501 859 participants recruited from the United Kingdom Biobank to explore the potential association between breastfeeding and the risk of lung cancer mortality using a Cox proportional hazards model. Subsequently, the polygenic risk score for lung cancer was calculated to detect interactions between genes and the environment. RESULTS: Over a median follow-up duration of 11.8 years, encompassing a total of 501 859 participants, breastfeeding was found to reduce the risk of lung cancer-related death and the impact of maternal smoking on lung cancer mortality in adult offspring. This association remained consistent after stratification. Furthermore, the influence of maternal smoking and breastfeeding on the risk of lung cancer mortality was significant at a high genetic risk level. CONCLUSION: Breastfeeding can reduce the risk of lung cancer-related death and the impact of maternal smoking on lung cancer mortality in adult offspring. This correlation has the potential to reduce the probability of lung-cancer-related deaths in subsequent generations.

Tailored Borneol-Modified Lipid Nanoparticles Nasal Spray for Enhanced Nose-to-Brain Delivery to Central Nervous System Diseases.

The nanodrug delivery system-based nasal spray (NDDS-NS) can bypass the blood-brain barrier and deliver drugs directly to the brain, offering unparalleled advantages in the treatment of central nervous system (CNS) diseases. However, the current design of NNDS-NS is excessively focused on mucosal absorption while neglecting the impact of nasal deposition on nose-to-brain drug delivery, resulting in an unsatisfactory nose-to-brain delivery efficiency. In this study, the effect of the dispersion medium viscosity on nasal drug deposition and nose-to-brain delivery in NDDS-NS was elucidated. The optimized formulation F5 (39.36 mPa·s) demonstrated significantly higher olfactory deposition fraction (ODF) of 23.58%, and a strong correlation between ODF and intracerebral drug delivery (R2 = 0.7755) was observed. Building upon this understanding, a borneol-modified lipid nanoparticle nasal spray (BLNP-NS) that combined both nasal deposition and mucosal absorption was designed for efficient nose-to-brain delivery. BLNP-NS exhibited an accelerated onset of action and enhanced brain targeting efficiency, which could be attributed to borneol modification facilitating the opening of tight junction channels. Furthermore, BLNP-NS showed superiority in a chronic migraine rat model. It not only provided rapid relief of migraine symptoms but also reversed neuroinflammation-induced hyperalgesia. The results revealed that borneol modification could induce the polarization of microglia, regulate the neuroinflammatory microenvironment, and repair the neuronal damage caused by neuroinflammation. This study highlights the impact of dispersion medium viscosity on the nose-to-brain delivery process of NDDS-NS and serves as a bridge between the formulation development and clinical transformation of NDDS-NS for the treatment of CNS diseases.

The Impact of School Reopening on Chinese Adolescents' Mental Health During COVID-19: Considering the Role of Academic Stress and Academic Orientation.

PURPOSE: Existing studies found that school closure during the COVID-19 pandemic negatively influenced adolescents' mental health. Yet, it remains unclear how adolescent mental health changed during the transition of school reopening as well as the academic-related risk and protective factors. METHODS: Immediately before (April 2020) and three months (July 2020) after school reopening, 879 adolescents in Shanghai, China (mean age = 13.14 years, standard deviation = 1.31, 51% girls) completed online surveys and reported on their mental health (i.e., depressive symptoms, anxiety symptoms, and anger problems). Adolescents also reported perceived academic stress and academic orientations (i.e., performance orientation and mastery orientation) before school reopening. RESULTS: Adolescents reported decreased depressive symptoms, anxiety symptoms, and anger problems three months after school reopening. Adolescents who reported higher perceived academic stress and performance orientation showed elevated mental health symptoms after school reopening, whereas those reported higher mastery orientation showed decreased anger problems. Higher mastery orientation buffered the negative influence of academic stress on mental health. DISCUSSION: The findings not only demonstrate the positive influence of school reopening on Chinese adolescents' mental health but also highlight the role of perceived academic stress and academic orientations in contributing to individual differences during this transition.

A Positioning Alarm System for Explosive Impact Debris Protective Suit Based on an Accelerometer Array.

Protection suits are vital for firefighters' safety. Traditional protection suits physically protect firemen from burns, but cannot locate the position of bodily injuries caused by impact debris. Herein, we present a wearable impact debris positioning system for firefighter protection suits based on an accelerometer array. Wearable piezoelectric accelerometers are distributed regularly on the suit to detect the vibration on different body parts, which is conducive to determining the position of injured body parts. In addition, the injured parts can be displayed on a dummy body model on the upper computer with a higher localization accuracy of 4 cm. The positioning alarm system has a rapid response time of 0.11 ms, attributed to the smart signal processing method. This work provides a reliable and smart method for locating and assessing the position of bodily injuries caused by impact debris, which is significant because it enables fire commanders to rescue injured firefighters in time.

Neoadjuvant chemotherapy with or without camrelizumab in resectable esophageal squamous cell carcinoma: the randomized phase 3 ESCORT-NEO/NCCES01 trial.

Recent single-arm studies involving neoadjuvant camrelizumab, a PD-1 inhibitor, plus chemotherapy for resectable locally advanced esophageal squamous cell carcinoma (LA-ESCC) have shown promising results. This multicenter, randomized, open-label phase 3 trial aimed to further assess the efficacy and safety of neoadjuvant camrelizumab plus chemotherapy followed by adjuvant camrelizumab, compared to neoadjuvant chemotherapy alone. A total of 391 patients with resectable thoracic LA-ESCC (T1b-3N1-3M0 or T3N0M0) were stratified by clinical stage (I/II, III or IVA) and randomized in a 1:1:1 ratio to undergo two cycles of neoadjuvant therapy. Treatments included camrelizumab, albumin-bound paclitaxel and cisplatin (Cam+nab-TP group; n = 132); camrelizumab, paclitaxel and cisplatin (Cam+TP group; n = 130); and paclitaxel with cisplatin (TP group; n = 129), followed by surgical resection. Both the Cam+nab-TP and Cam+TP groups also received adjuvant camrelizumab. The dual primary endpoints were the rate of pathological complete response (pCR), as evaluated by a blind independent review committee, and event-free survival (EFS), as assessed by investigators. This study reports the final analysis of pCR rates. In the intention-to-treat population, the Cam+nab-TP and Cam+TP groups exhibited significantly higher pCR rates of 28.0% and 15.4%, respectively, compared to 4.7% in the TP group (Cam+nab-TP versus TP: difference 23.5%, 95% confidence interval (CI) 15.1-32.0, P < 0.0001; Cam+TP versus TP: difference 10.9%, 95% CI 3.7-18.1, P = 0.0034). The study met its primary endpoint of pCR; however, EFS is not yet mature. The incidence of grade ≥3 treatment-related adverse events during neoadjuvant treatment was 34.1% for the Cam+nab-TP group, 29.2% for the Cam+TP group and 28.8% for the TP group; the postoperative complication rates were 34.2%, 38.8% and 32.0%, respectively. Neoadjuvant camrelizumab plus chemotherapy demonstrated superior pCR rates compared to chemotherapy alone for LA-ESCC, with a tolerable safety profile. Chinese Clinical Trial Registry identifier: ChiCTR2000040034 .

3D bioprinting of an in vitro hepatoma microenvironment model: Establishment, evaluation, and anticancer drug testing.

Tumor behavior, including its response to treatments, is influenced by interactions between mesenchymal and malignant cells, as well as their spatial arrangement. To study tumor biology and evaluate anticancer drugs, accurate 3D tumor models are essential. Here, we developed an in vitro biomimetic hepatoma microenvironment model by combining an extracellular matrix (3DM-7721). Initially, the internal grid structure, composed of 10/6 % GelMA/gelatin loaded with SMMC-7721 cells, was printed using 3D bioprinting. The external component consisted of fibroblasts and human umbilical vein endothelial cells loaded with 10/3 % GelMA/gelatin. A control model (3DP-7721) lacked external cell loading. GelMA/gelatin hydrogels provided robust structural support and biocompatibility. The SMMC-7721 cells in the 3DM-7721 model exhibit superior tumor-associated gene expression and proliferation characteristics when compared to the 3DP-7721 model. Furthermore, the 3DM-7721 type exhibited increased resistance to anticancer agents. SMMC-7721 cells in the 3DM-7721 model exhibit significant tumorigenicity in nude mice. The 3DM-7721 model group showed pathological characteristics of malignant tumors, with a high degree of deterioration, and a significant positive correlation between malignant tumor-related gene pathways. This high-fidelity 3DM-7721 tumor microenvironment model is invaluable for studying tumor progression, devising effective treatment strategies, and discovering drugs. STATEMENT OF SIGNIFICANCE.

Engineering Escherichia coli to Efficiently Produce Colanic Acid with Low Molecular Mass and Viscosity.

Colanic acid (CA) is exopolysaccharide that presents growing potential in the food and healthcare industry as a versatile polymer. Previously, we have constructed the Escherichia coli strain WWM16 which can efficiently produce CA. In this study, WWM16 has been further engineered to produce a higher yield of CA with low molecular mass and viscosity. The gene mcbR encoding a transcriptional factor, and the genes opgD, opgG, and opgH related to the biosynthesis of osmoregulated periplasmic glucans were deleted in E. coli WWM16, and the resulting strain WWM166 produced 18.1 g/L CA. The expression level of wcaD encoding the polymerase in WWM166 was downregulated using CRISPRi. As a result, the strain WWM166/pWpD1 could produce 49.9 g/L CA with lower molecular mass. CA products were purified from both WWM166 and WWM166/pWpD1, and their molecular mass, viscosity, fluidity, hygroscopicity, and antioxidant activity were determined and compared. These findings demonstrate the potential application of CA with different molecular masses to prolong life and protect skin in the food and cosmetic industries.