Effect of dietary supplementation with recombinant human lysozyme on growth performance, antioxidative characteristics, and intestinal health in broiler chickens.

Lysozyme is often used as a feed additive to act as an antibacterial protein that boosts the immune system of livestock and poultry while protecting against pathogens. To investigate the effects of recombinant human lysozyme (rhLYZ) from Pichia pastoris and chlortetracycline on broiler chicken's production performance, antioxidant characteristics, and intestinal microbiota, a total of 200, 1-d-old male Arbor Acres broiler chickens (46.53 ±â€…0.42 g) were selected for a 42-d experiment. Dietary treatments included a basal diet of corn-soybean meal supplemented with either 0 mg/kg (CON), 50 mg/kg aureomycin (ANT), 20 mg/kg rhLYZ (LOW), 60 mg/kg rhLYZ (MEDIUM), or 180 mg/kg rhLYZ (HIGH). Compared with CON, MEDIUM diet increased (P < 0.05) average daily gain (67.40 g) of broilers from day 22 to 42. In the early (1.29) and overall phases (1.69), MEDIUM led to a reduction (P < 0.05) in the feed conversion ratio of broiler chickens. Furthermore, in comparison to the CON and ANT, MEDIUM exhibited reduced (P < 0.05) levels of INF-γ and tumor necrosis factor-α in the serum. In the cecum, the abundance of Monoglobus and Family_XIII_AD3011_group was lower (P < 0.05) in the MEDIUM treatment compared to CON. Overall, supplementation of 60 mg/kg of rhLYZ improved growth performance, nutrient utilization efficiency, and serum immune function, while also influencing the composition of intestinal microbiota. This suggests lysozyme's potential to replace antibiotic additives in feed.

The aim of this study was to explore the effects of recombinant human lysozyme (rhLYZ) produced from Pichia pastoris and chlortetracycline on broiler chicken performance, antioxidant properties, and gut microbiota. A 42-d experiment was conducted, involving 200 1-d-old male Arbor Acres broiler chickens. We provided different diets: a standard diet (CON), a diet with 50 mg/kg aureomycin (ANT), a diet with 20 mg/kg rhLYZ (LOW), a diet with 60 mg/kg rhLYZ (MEDIUM), or a diet with 180 mg/kg rhLYZ (HIGH). The results showed that, compared to the control group, the MEDIUM group significantly increased the average daily gain of broilers to 67.40 g from day 22 to 42. Additionally, the MEDIUM group exhibited a reduced feed conversion ratio during both the early and overall growth stages of the chickens. Furthermore, serum levels of INF-γ and tumor necrosis factor-α were lower in the MEDIUM group compared to both the CON and ANT groups. In the cecum, the abundance of Monoglobus and Family_XIII_AD3011_group was also lower in the MEDIUM treatment compared to the CON group. Overall, supplementation with 60 mg/kg of rhLYZ improved growth performance, nutrient utilization efficiency, and serum immune function in broiler chickens while also influencing the composition of their intestinal microbiota. This suggests the potential of lysozyme as a replacement for antibiotic additives in feed.

Molecular classifications of prostate cancer: basis for individualized risk stratification and precision therapy.

Tumour classifications play a pivotal role in prostate cancer (PCa) management. It can predict the clinical outcomes of PCa as early as the disease is diagnosed and then guide therapeutic schemes, such as active monitoring, standalone surgical intervention, or surgery supplemented with postoperative adjunctive therapy, thereby circumventing disease exacerbation and excessive treatment. Classifications based on clinicopathological features, such as prostate cancer-specific antigen, Gleason score, and TNM stage, are still the main risk stratification strategies and have played an essential role in standardized clinical decision-making. However, mounting evidence indicates that clinicopathological parameters in isolation fail to adequately capture the heterogeneity exhibited among distinct PCa patients, such as those sharing identical Gleason scores yet experiencing divergent prognoses. As a remedy, molecular classifications have been introduced. Currently, molecular studies have revealed the characteristic genomic alterations, epigenetic modulations, and tumour microenvironment associated with different types of PCa, which provide a chance for urologists to refine the PCa classification. In this context, numerous invaluable molecular classifications have been devised, employing disparate statistical methodologies and algorithmic approaches, encompassing self-organizing map clustering, unsupervised cluster analysis, and multifarious algorithms. Interestingly, the classifier PAM50 was used in a phase-2 multicentre open-label trial, NRG-GU-006, for further validation, which hints at the promise of molecular classification for clinical use. Consequently, this review examines the extant molecular classifications, delineates the prevailing panorama of clinically pertinent molecular signatures, and delves into eight emblematic molecular classifications, dissecting their methodological underpinnings and clinical utility.

Effects of nutrient injection on the Xinjiang oil field microbial community studied in a long core flooding simulation device.

Microbial Enhanced Oil Recovery (MEOR) is an option for recovering oil from depleted reservoirs. Numerous field trials of MEOR have confirmed distinct microbial community structure in diverse production wells within the same block. The variance in the reservoir microbial communities, however, remains ambiguously documented. In this study, an 8 m long core microbial flooding simulation device was built on a laboratory scale to study the dynamic changes of the indigenous microbial community structure in the Qizhong Block, Xinjiang oil field. During the MEOR, there was an approximate 34% upswing in oil extraction. Based on the 16S rRNA gene high-throughput sequencing, our results indicated that nutrition was one of the factors affecting the microbial communities in oil reservoirs. After the introduction of nutrients, hydrocarbon oxidizing bacteria became active, followed by the sequential activation of facultative anaerobes and anaerobic fermenting bacteria. This was consistent with the hypothesized succession of a microbial ecological "food chain" in the reservoir, which preliminarily supported the two-step activation theory for reservoir microbes transitioning from aerobic to anaerobic states. Furthermore, metagenomic results indicated that reservoir microorganisms had potential functions of hydrocarbon degradation, gas production and surfactant production. Understanding reservoir microbial communities and improving oil recovery are both aided by this work.

HMDB: A curated database of genes involved in hydrocarbon monooxygenation reaction with homologous genes as background.

The investigation of hydrocarbon degradation potential of environmental microorganisms is an important research topic, whether for the global carbon cycle or oil pollution remediation. Under aerobic conditions, the microorganisms employ a range of monooxygenases to use hydrocarbons substrates as a source of carbon and energy. With the explosion of sequencing data, mining genes in genomes or metagenomes has become computationally expensive and time-consuming. We proposed the HMDB, which is a professional gene database of hydrocarbon monooxygenases. HMDB contains 38 genes, which encode 11 monooxygenases responsible for the hydroxylation of 8 hydrocarbons. To reduce false positives, the strategy of using homologous genes as background noise was applied for HMDB. We added 10,095 gene sequences of homologous enzymes which took non-hydrocarbons as substrates to HMDB. The classic BLAST method and best-hit strategy were recommended for HMDB usage, but not limited. The performance of HMDB was validated using 264,402 prokaryote genomes from RefSeq and 51 metagenomes from SRA. The results showed that HMDB database had high sensitivity and low false positive rate. We release the HMDB database here, hoping to speed up the process for investigation of hydrocarbon monooxygenases in massive metagenomic data. HMDB is freely available at http://www.orgene.net/HMDB/.

Application of Dexmedetomidine in Surgical Anesthesia for Gastric Cancer and Its Effects on IL-1ß, IL-6, TNF-α and CRP.

This study was performed to analyze the application of dexmedetomidine (Dex) in anesthesia for gastric cancer surgery and its effect on serum inflammatory factors in patients. In this regard, a total of 78 patients with gastric cancer who were hospitalized in our hospital from January 2020 to September 2023 and received general intravenous anesthesia were randomly divided into two groups (n=39 in each group). The conventional group was given the same volume of 0.9% sodium chloride solution 10min before induction of anesthesia, and the Dex group was given Dex1µg/kg intravenous pump 10min before induction of anesthesia. The hemodynamics, serum levels of IL-1ß, IL-6, TNF-α, CRP, propofol, remifentanil, and the total incidence of adverse reactions were compared between the two groups at different periods. The results showed that the mean arterial pressure (MAP), heart rate (HR), serum IL-1ß, IL-6, TNF-α and CRP in the Dex group were compared with those in the routine group (P>0.05). MAP and HR in T1, T2 and T3Dex groups were lower than those in the conventional group (P<0.05). The serum levels of IL-1ß, IL-6, TNF-α and CRP in T4 and T5 of the Dex group were lower than those of the routine group (P<0.05). The dosage of propofol and remifentanil in the Dex group was lower than those in the conventional group (P<0.05). The total incidence of adverse reactions in the Dex group (5.13%) was compared with that in the conventional group (10.26%), P>0.05. It was concluded that Dex can effectively maintain the stability of hemodynamics during gastric cancer surgery, reduce the dosage of propofol and other anesthetic drugs, reduce inflammation, and has a certain safety without obvious adverse reactions.

Hybrid biofabrication of neurosecretory structures as a model for neurosecretion.

The present study aimed to combine extrusion-based three-dimensional (3D) bioprinting and polymer nanofiber electrospinning technology to fabricate tissue-like structures with neurosecretory function in vitro. Using neurosecretory cells as cell resources, sodium alginate/gelatin/fibrinogen as matrix, polylactic acid/gelatin electrospun nanofibers as diaphragm, and neurosecretory cells-loaded 3D hydrogel scaffolds were bioprinted and then covered with electrospun nanofibers layer-by-layer. The morphology was observed by scanning electron microscopy and transmission electron microscopy (TEM), and the mechanical characteristics and cytotoxicity of the hybrid biofabricated scaffold structure were evaluated. The 3D-bioprinted tissue activity, including cell death and proliferation, was verified. Western blotting and ELISA experiments were used to confirm the cell phenotype and secretory function, while animal in vivo transplantation experiments confirmed the histocompatibility, inflammatory reaction, and tissue remodeling ability of the heterozygous tissue structures. Neurosecretory structures with 3D structures were successfully prepared by hybrid biofabrication in vitro. The mechanical strength of the composite biofabricated structures was significantly higher than that of the hydrogel system (P < 0.05). The survival rate of PC12 cells in the 3D-bioprinted model was 92.849 ± 2.995%. Hematoxylin and eosin-stained pathological sections showed that the cells grew in clumps, and there was no significant difference in the expression of MAP2 and tubulin-ß between 3D organoids and PC12 cells. The results of ELISA showed that the PC12 cells in 3D structures retained the ability to continuously secrete noradrenaline and met-enkephalin, and the secretory vesicles around and within the cells could be observed by TEM. In in vivo transplantation, PC12 cells gathered and grew in clusters, maintained high activity, neovascularization, and tissue remodeling in 3D structures. The neurosecretory structures were biofabricated by 3D bioprinting and nanofiber electrospinning in vitro, which had high activity and neurosecretory function. In vivo transplantation of neurosecretory structures showed active proliferation of cells and potential for tissue remodeling. Our research provides a new method for biological manufacture of neurosecretory structures in vitro, which maintains neurosecretory function and lays the foundation for the clinical application of neuroendocrine tissues.

Stress-responses of microbes in oil reservoir under high tetracycline exposure and their environmental risks.

As the groundwater ecosystem is connected with surface, antibiotics and antibiotic resistance genes (ARGs) in aquatic environments will gradually infiltrate into the deep environment, posing a potential threat to groundwater ecosystem. However, knowledge on the environmental risk of antibiotics and ARGs in groundwater ecosystem and their ecological process still remains unexplored. In this study, lab-scale oil reservoirs under high tetracycline stress were performed to evaluate the dynamics of microbial communities, ARGs and potential functions by using 16S rRNA gene sequencing and metagenomics analysis. Although the presence of antibiotics remarkably reduced the microbial abundance and diversity in a short term, but remain stable or even increased after a long-term incubation. Antibiotic stress caused a greater diversity and abundance of ARGs, and higher numbers of ARGs-related species with the capacity to transfer ARGs to other microbes through horizontal gene transfer. Thus, a much more frequent associations of microbial community at both node- and network-level and a selective pressure on enrichment of antibiotic resistant bacteria related to "anaerobic n-alkane degradation" and "methylotrophic methanogenesis" were observed. It is important to emphasize that high antibiotic stress could also prevent some microbes related to "Sulfate reduction", "Fe(II) oxidation", "Nitrate reduction", and "Xylene and Toluene degradation". This study provides an insight into the long-term stress-responses of microbial communities and functions in oil reservoir under tetracycline exposure, which may help to elucidate the effect of antibiotic stress on biogeochemical cycling with microbial involvement in groundwater ecosystem.

Clinical efficacy and safety of posterior minimally invasive surgery in cervical spondylosis: a systematic review.

BACKGROUND: Posterior minimally invasive surgery has been increasingly used in in recent years for the clinical treatment of cervical spondylosis. However, this treatment remains challenging and has not been comprehensively reported. The aim of this study was to provide a systematic review of posterior minimally invasive treatment for cervical spondylosis to demonstrate the clinical efficacy and safety of this procedure. METHOD: We collected information from patients with myelopathy or radiculopathy cervical spondylosis who underwent posterior minimally invasive surgery and verified the clinical efficacy and safety of these surgeries with different measurement indicators from five electronic databases: the Nurick, visual analog scale score, Japanese Orthopaedic Association (JOA) score, Neck Disability Index (NDI), EuroQol Five Dimensions Questionnaire (EQ-5D) score, Short-Form Health Survey Physical Component Summary (SF12-PCS) questionnaire score, Short-Form Health Survey Mental Component Summary (SF12-MCS) questionnaire score, and the MOS item short form health survey (HF-36) score. The decompression effect, cervical spine stability, average surgery time, surgical blood loss volume, length of hospital stay, and related complications were included in the descriptive analysis. Reporting of this protocol followed the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines checklist. RESULTS: We identified 14 observational studies of cervical spondylosis with 479 patients, mainly including 197 cases of myelopathy and 207 cases of radiculopathy. Channel and endoscopic techniques were used. This study was certified by PROSPERO: CRD42021290074. Significant improvements in the quantitative indicators (Neck-VAS in 9 studies, JOA in 7 studies, NDIs in 5 studies, Nurick, ARM-VAS, and EQ-5D in 2 studies each, and the SF12-PCS, SF12-MCS, and HF-36 in 1 study each) were observed between pre- and postoperation (P < 0.05), and satisfactory clinical significance was acquired in the descriptive indicators [average surgery time (94.56 ± 37.26 min), blood loss volume (68.78 ± 103.31 ml), average length of stay (2.39 ± 1.20 d), and cervical spine stability after surgery]. Additionally, we showed that there was a 4.9% postoperative complication rate and the types of complications that may occur. CONCLUSION: Posterior minimally invasive surgery is an effective and safe method for the treatment of cervical spondylosis and is a recommended optional surgical procedure for single-segment myelopathy and radiculopathy.

DNA N6-Methyladenine Modification in Eukaryotic Genome.

DNA methylation is treated as an important epigenetic mark in various biological activities. In the past, a large number of articles focused on 5 mC while lacking attention to N6-methyladenine (6 mA). The presence of 6 mA modification was previously discovered only in prokaryotes. Recently, with the development of detection technologies, 6 mA has been found in several eukaryotes, including protozoans, metazoans, plants, and fungi. The importance of 6 mA in prokaryotes and single-celled eukaryotes has been widely accepted. However, due to the incredibly low density of 6 mA and restrictions on detection technologies, the prevalence of 6 mA and its role in biological processes in eukaryotic organisms are highly debated. In this review, we first summarize the advantages and disadvantages of 6 mA detection methods. Then, we conclude existing reports on the prevalence of 6 mA in eukaryotic organisms. Next, we highlight possible methyltransferases, demethylases, and the recognition proteins of 6 mA. In addition, we summarize the functions of 6 mA in eukaryotes. Last but not least, we summarize our point of view and put forward the problems that need further research.

Fusion between Glioma Stem Cells and Mesenchymal Stem Cells Promotes Malignant Progression in 3D-Bioprinted Models.

The interaction between glioma stem cells (GSCs) and mesenchymal stem cells (MSCs) in the glioma microenvironment is considered to be an important factor in promoting tumor progression, but the mechanism is still not fully elucidated. To further elucidate the interaction between GSCs and MSCs, two 3D-bioprinted tumor models (low-temperature molding and coaxial bioprinting) were used to simulate the tumor growth microenvironment. Cell fusion between GSCs and MSCs was found by the method of Cre-LoxP switch gene and RFP/GFP dual-color fluorescence tracing. The fused cells coexpressed biomarkers of GSCs and MSCs, showing stronger proliferation, cloning, and invasion abilities than GSCs and MSCs. In addition, the fused cells have stronger tumorigenic properties in nude mice, showing the pathological features of malignant tumors. In conclusion, GSCs and MSCs undergo cell fusion in 3D-bioprinted models, and the fused cells have a higher degree of malignancy than parental cells, which promotes the progression of glioma.

Low cervical vertebral CT value increased early subsidence of titanium mesh cage after anterior cervical corpectomy and fusion.

STUDY DESIGN: This study was a retrospective review. OBJECTIVE: To study the predictive effect of Hounsfield units (HU) value in the cervical vertebral body derived from computed tomography (CT) on the early titanium mesh cage (TMC) subsidence after anterior cervical corpectomy and fusion (ACCF). METHODS: This retrospective study was conducted on patients who underwent ACCF at one institution between January 2014 and December 2018. We collected date included age, gender, body mass index (BMI), disease type, surgical segment, whether merge ACDF, HU value of the vertebral body and endplate, vertebral body height loss, cervical lordosis angle, and cervical sagittal alignment. VAS, JOA, and NDI were used to assess clinical efficacy. Univariate analysis was performed to screen the influencing factors of TMC subsidence, and then logistic regression was used to find out the independent risk factors. The ROC curve and area under curve (AUC) were used to analyze the HU value to predict the TMC subsidence. RESULTS: A total of 85 patients who accepted ACCF were included in this study, and early titanium mesh cage subsidence was demonstrated in 29 patients. The subsidence rate was 34.1%. The JOA, VAS, and NDI scores significantly improved in both groups after the operation. Between the subsidence and non-subsidence groups, there were significant differences in age, intervertebral distraction height, and HU value in both upper and lower vertebral body and endplate. The logistic regression analysis proved that the HU value of the lower vertebral body was an independent risk of TMC subsidence, the AUC was 0.866, and the most appropriate threshold of the HU value was 275 (sensitivity: 87.5%, specificity: 79.3%). CONCLUSION: Preoperative cervical CT value is an independent correlative factor for early TMC subsidence after ACCF, and patients with a low CT value of the inferior vertebral body of the operative segment have a higher risk of TMC subsidence in the early postoperative period. TRIAL REGISTRATION: This study is undergoing retrospective registration.

CnnPOGTP: a novel CNN-based predictor for identifying the optimal growth temperatures of prokaryotes using only genomic k-mers distribution.

SUMMARY: Temperature is very important for the growth of microorganisms. Appropriate temperature conditions can improve the possibility for isolation of currently uncultured microorganisms. The development of metagenomic binning technology had dramatically increased the availability of genomic information of prokaryotes, providing convenience to infer the optimal growth temperature (OGT). Here, we proposed CnnPOGTP, a predictor for OGTs of prokaryotes based on deep learning method using only k-mers distribution derived from genomic sequence. This method was annotation free, and the predicted OGT could be obtained by simply providing the genome sequence to the CnnPOGTP website. AVAILABILITY AND IMPLEMENTATION: http://www.orgene.net/CnnPOGTP. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Deep mining decreases the microbial taxonomic and functional diversity of subsurface oil reservoirs.

Microbes in subsurface oil reservoirs play important roles in elemental cycles and biogeochemical processes. However, the community assembly pattern of indigenous microbiome and their succession under long-term human activity remain poorly understood. Here we studied the microbial community assembly in underground sandstone cores from 190 to 2050 m in northeast China and their response to long-term oil recovery (10-50 years). Indigenous microbiome in subsurface petroleum reservoirs were dominated by Gammaproteobacteria, Firmicutes, Alphaproteobacteria, Bacteroidetes, and Actinobacteria, which exhibited a higher contribution of homogenizing dispersal assembly and different taxonomy distinct ecological modules when compared with perturbed samples. Specifically, the long-term oil recovery reduced the bacterial taxonomic- and functional-diversity, and increased the community co-occurrence associations in subsurface oil reservoirs. Moreover, distinguished from the perturbed samples, both variation partition analysis and structural equation model revealed that the contents of quartz, NO3- and Cl- significantly structured the α- and ß-diversity in indigenous subsurface bacterial communities. These findings first provide the holistic picture of microbiome in the deep oil reservoirs, which demonstrate the significant impact of human activity on microbiome in deep continental subsurface.

Stochastic assembly process dominates bacterial succession during a long-term microbial enhanced oil recovery.

Microbial enhanced oil recovery (MEOR) has been successfully used in oil exploitation to increase oil production. However, the mechanisms of microbial interactions and community assembly related to oil production performance along MEOR process are poorly understood. Here, we investigated the microbiome of an oil reservoir for a period of 5 years under three phases of different treatments with the injection of a mixture of microbes, nutrients, and air at different intensity. During the MEOR process, amplification of functional genes revealed an increase of genes related to hydrocarbon degradation linked to methanogenesis, supported by stable isotope analysis for confirmation of the methanogenesis activity. Meanwhile, a lower contribution of the ubiquitous/common taxa, closer and more positive associations, and lower modularity were observed in bacterial co-occurrence networks, with the rare taxa being the keystone taxa. The null model analysis and structural equation modeling revealed that the contribution of stochastic processes affected by functional groups and co-occurrence patterns to bacterial community increased significantly with the increase of oil production. This provides new insight that stochastic assembly in bacterial community increased along with MEOR process, and it is worthwhile paying attention to the uncertain consequences caused by random evolution since the treatment effect of MEOR is closely related to the in-situ community in oil reservoir.

Disentangling the distinct mechanisms shaping the subsurface oil reservoir bacterial and archaeal communities across northern China.

Microbes in surface ecosystem exhibit strong biogeographic patterns, and are less apparent after human management. However, in contrast with the considerable knowledge on the surface ecosystem, the microbial biogeographic patterns in deep subsurface ecosystem under artificial disturbance is poorly understood. Here, we explored the spatial scale-dependence patterns of bacterial and archaeal communities in oil reservoirs under different artificial flooding duration and environmental conditions across northern China. Bacterial and archaeal communities of oil reservoirs exhibited distinct assembly patterns with a stronger distance-decay relationship in archaeal communities than bacterial communities, as different environmental factors linked to the diversity of bacteria and archaea. Specifically, bacterial and archaeal network properties revealed a significant correlation with spatial reservoir isolation by distinct co-occurrence patterns. The co-occurrences of bacterial communities were more complex in high temperature and alkaline pH, while archaeal co-occurrences were more frequent in low temperature and neutral pH. Potential functions in bacterial communities were more connected with chemoheterotrophy, whereas methanogenesis was abundant in archaeal communities, as confirmed by both keystone taxa and main ecological clusters in networks. This revealed that different mechanisms underlain geography and co-occurrence patterns of bacteria and archaea in oil reservoirs, providing a new insight for understanding biogeography and coexistence theory in deep subsurface ecosystem.

S100A11 Promotes Glioma Cell Proliferation and Predicts Grade-Correlated Unfavorable Prognosis.

The prognosis of glioma is significantly correlated with the pathological grades; however, the correlations between the prognostic biomarkers with pathological grades have not been elucidated. S100A11 is involved in a variety of malignant biological processes of tumor, whereas its biological and clinicopathological features on glioma remain unclear. In this study, the S100A11 expression and clinical information were obtained from the public databases (TCGA, GEPIA2) to analyze its correlations with the pathological grade and the prognosis of glioma patients. We then verified the expression of S100A11 by immunohistochemistry staining. The effects of S100A11 on the proliferation of glioma cells were confirmed by cytological function assays (CCK-8, Flow cytometry, Clone formation assay) in vitro, the role of S100A11 in regulation of glioma growth was determined by xenograft model assay. We observed that S100A11 expression positively correlated with the pathological grades, while negatively correlated with the survival time of patients. In cytological analysis, we found the proliferations of glioma cell lines were significantly inhibited in vitro (P < 0.05) after interfering S100A11 expression via shRNAs. The cell cycle was blocked at G0/G1 stage. The ability of clone formation was significantly decreased, and the tumorigenicity in vivo was weakened (P < 0.05). In summary, S100A11 was over-expressed in gliomas and positively correlated with the pathological grades. Interfering the expression of S100A11 significantly inhibited the proliferation of glioma in vitro and the tumorigenicity in vivo (P < 0.05). In conclusion, S100A11 might be considered as a potential biomarker in glioma.

MiR-599 Protects Cardiomyocytes against Oxidative Stress-Induced Pyroptosis.

Oxidative stress is a crucial factor and key promoter of a variety of cardiovascular diseases associated with cardiomyocyte injury. Emerging literatures suggest that pyroptosis plays a key role in cardiac damages. However, whether pyroptosis contributes to cardiomyocyte injury under oxidative stress and the underlying molecular mechanisms are totally unclear. This study was designed to investigate the potential role of pyroptosis in H2O2-induced cardiomyocyte injury and to elucidate the potential mechanisms. Primary cardiomyocytes from neonatal Wistar rats were utilized. These myocytes were treated with different concentrations of H2O2 (25, 50, and 100 µM) for 24 h to induce oxidative injury. Our results indicated that mRNA and protein levels of ASC were remarkably upregulated and caspase-1 was activated. Moreover, the expressions of inflammatory factors IL-1ß and IL-18 were also increased. Luciferase assay showed that miR-599 inhibited ASC expression through complementary binding with its 3'UTR. MiR-599 expression was substantially reduced in H2O2-treated cardiomyocytes. Upregulation of miR-599 inhibited cardiomyocyte pyroptosis under oxidative stress, and opposite results were found by decreasing the expression of miR-599. Consistently, miR-599 overexpression ameliorated cardiomyocyte injury caused by H2O2. Therefore, miR-599 could be a promising therapeutic approach for the management of cardiac injury under oxidative condition.

Tailor-made polysaccharides containing uniformly distributed repeating units based on the xanthan gum skeleton.

Xanthan gum, whose structure determines its physicochemical properties, is an important microbial polysaccharide. Currently, marketed xanthan products are produced by wild-type strains followed by post-fermentation separation or chemical modification, which are complicated and labor-intensive. In the present study, we designed eight polysaccharides containing uniformly distributed repeating units and different rheological properties based on natural xanthan skeleton and according to the relationship between property and structure. The customized polysaccharides were produced in Xanthomonas campestris CGMCC 15155 using marker-less gene knockout and gene overexpression methods. The results showed that their different homogeneous primary structures determined their specific secondary structures and rheological properties, especially the terminal mannose, the pyruvyl group, and the acetyl group attached to the internal mannose of the side chain. Polysaccharides lacking a terminal mannose, such as xanthan XdM-0 and XdM-A, had reduced zero-shear viscosity and modulus values. The internal acetyl group of the side chain stabilized the helix structure (e.g., in XG-A0), while the pyruvate group had the opposite effect (e.g., in XG-AP and XG-0P). The eight xanthan variants provide a promising theoretical foundation to further study the structure-activity relationship of xanthan and will help to construct xanthan-containing block copolymers.