29 research outputs found

    The biological function of the type II toxin-antitoxin system ccdAB in recurrent urinary tract infections

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    Urinary tract infections (UTIs) represent a significant challenge in clinical practice, with recurrent forms (rUTIs) posing a continual threat to patient health. Escherichia coli (E. coli) is the primary culprit in a vast majority of UTIs, both community-acquired and hospital-acquired, underscoring its clinical importance. Among different mediators of pathogenesis, toxin-antitoxin (TA) systems are emerging as the most prominent. The type II TA system, prevalent in prokaryotes, emerges as a critical player in stress response, biofilm formation, and cell dormancy. ccdAB, the first identified type II TA module, is renowned for maintaining plasmid stability. This paper aims to unravel the physiological role of the ccdAB in rUTIs caused by E. coli, delving into bacterial characteristics crucial for understanding and managing this disease. We investigated UPEC-induced rUTIs, examining changes in type II TA distribution and number, phylogenetic distribution, and Multi-Locus Sequence Typing (MLST) using polymerase chain reaction (PCR). Furthermore, our findings revealed that the induction of ccdB expression in E. coli BL21 (DE3) inhibited bacterial growth, observed that the expression of both ccdAB and ccdB in E. coli BL21 (DE3) led to an increase in biofilm formation, and confirmed that ccdAB plays a role in the development of persistent bacteria in urinary tract infections. Our findings could pave the way for novel therapeutic approaches targeting these systems, potentially reducing the prevalence of rUTIs. Through this investigation, we hope to contribute significantly to the global effort to combat the persistent challenge of rUTIs

    Hepatocyte Nuclear Factor 4α (HNF4α) Is a Transcription Factor of Vertebrate Fatty Acyl Desaturase Gene as Identified in Marine Teleost Siganus canaliculatus

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    Rabbitfish Siganus canaliculatus was the first marine teleost demonstrated to have the capability of biosynthesizing long-chain polyunsaturated fatty acids (LC-PUFA) from C18 precursors, and to possess a Δ4 fatty acyl desaturase (Δ4 Fad) which was the first report in vertebrates, and is a good model for studying the regulatory mechanisms of LC-PUFA bio- synthesis in teleosts. In order to understand regulatory mechanisms of transcription of Δ4 Fad, the gene promoter was cloned and characterized in the present study. An upstream sequence of 1859 bp from the initiation codon ATG was cloned as the promoter candidate. On the basis of bioinformatic analysis, several binding sites of transcription factors (TF) including GATA binding protein 2 (GATA-2), CCAAT enhancer binding protein (C/EBP), nuclear factor 1 (NF-1), nuclear factor Y (NF-Y), hepatocyte nuclear factor 4α (HNF4α) and sterol regulatory element (SRE), were identified in the promoter by site-directed mutation and functional assays. HNF4α and NF-1 were confirmed to interact with the core promoter of Δ4 Fad by gel shift assay and mass spectrometry. Moreover, over-expression of HNF4α increased promoter activity in HEK 293T cells and mRNA level of Δ4 Fad in rabbitfish pri- mary hepatocytes, respectively. The results indicated that HNF4α is a TF of rabbitfish Δ4 Fad. To our knowledge, this is the first report on promoter structure of a Δ4 Fad, and also the first demonstration of HNF4α as a TF of vertebrate Fad gene involved in transcription regulation of LC-PUFA biosynthesis

    Impact of Chemotherapy Regimens on Normal Tissue Complication Probability Models of Acute Hematologic Toxicity in Rectal Cancer Patients Receiving Intensity Modulated Radiation Therapy With Concurrent Chemotherapy From a Prospective Phase III Clinical Trial

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    Purpose: To determine whether there are differences in bone marrow tolerance to chemoradiotherapy (CRT) between two chemotherapy regimens according to FOWARC protocol and how chemotherapy regimens affect radiation dose parameters and normal tissue complication probability (NTCP) modelings that correlate with acute hematologic toxicity (HT) in rectal cancer patients treated with intensity modulated radiation therapy (IMRT) and concurrent chemotherapy.Materials and Methods: One hundred and twenty-eight rectal cancer patients who received IMRT from a single institution were recruited from Chinese FOWARC multicenter, open-label, randomized phase III trial. We assessed HT in these patients who were separated into two groups: Oxaliplatin (L-OHP) + 5- fluorouracil (5FU) (FOLFOX, 70 of 128) and 5FU (58 of 128). The pelvic bone marrow (PBM) was divided into three subsites: lumbosacral spine (LSS), ilium (I), and lower pelvic (LP). The endpoint for HT was grade ≥3 (HT3+) and grade ≥2 (HT2+) leukopenia, neutropenia, anemia and thrombocytopenia. Logistic regression was used to analyze the association between HT2+/HT3+ and dosimetric parameters. Lyman-Kutcher-Burman (LKB) model was used to calculate NTCP.Results: Sixty-eight patients experienced HT2+: 22 of 58 (37.9%) 5FU and 46 of 70 (65.7%) FOLFOX (p = 0.008), while twenty-six patients experienced HT3+: 4 of 58 (6.9%) 5FU and 22 of 70 (31.4%) FOLFOX (p = 0.016). PBM and LP dosimetric parameters were correlated with HT2+ in the 5FU group but not in the FOLFOX group. No PBM dosimetric parameters were correlated with HT3+ in both groups. For PBM, NTCP at HT3+ was 0.32 in FOLFOX group relative to 0.10 in 5FU subset (p < 0.05).Conclusion: Patients receiving FOLFOX have lower BM tolerance to CRT than those receiving 5FU. Low-dose radiation to the PBM is predictive for HT2+ in patients who received 5FU. NTCP modeling in FOLFOX group predicts much higher risk of HT3+ than 5FU group

    ERNIE-ViLG 2.0: Improving Text-to-Image Diffusion Model with Knowledge-Enhanced Mixture-of-Denoising-Experts

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    Recent progress in diffusion models has revolutionized the popular technology of text-to-image generation. While existing approaches could produce photorealistic high-resolution images with text conditions, there are still several open problems to be solved, which limits the further improvement of image fidelity and text relevancy. In this paper, we propose ERNIE-ViLG 2.0, a large-scale Chinese text-to-image diffusion model, which progressively upgrades the quality of generated images~by: (1) incorporating fine-grained textual and visual knowledge of key elements in the scene, and (2) utilizing different denoising experts at different denoising stages. With the proposed mechanisms, ERNIE-ViLG 2.0 not only achieves the state-of-the-art on MS-COCO with zero-shot FID score of 6.75, but also significantly outperforms recent models in terms of image fidelity and image-text alignment, with side-by-side human evaluation on the bilingual prompt set ViLG-300

    Analysis of genetic structure and function of clustered regularly interspaced short palindromic repeats loci in 110 Enterococcus strains

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    Clustered regularly interspaced short palindromic repeats (CRISPR) and their CRISPR-associated proteins (Cas) are an adaptive immune system involved in specific defenses against the invasion of foreign mobile genetic elements, such as plasmids and phages. This study aims to analyze the gene structure and to explore the function of the CRISPR system in the Enterococcus genome, especially with regard to drug resistance. The whole genome information of 110 enterococci was downloaded from the NCBI database to analyze the distribution and the structure of the CRISPR-Cas system including the Cas gene, repeat sequences, and spacer sequence of the CRISPR-Cas system by bioinformatics methods, and to find drug resistance-related genes and analyze the relationship between them and the CRISPR-Cas system. Multilocus sequence typing (MLST) of enterococci was performed against the reference MLST database. Information on the drug resistance of Enterococcus was retrieved from the CARD database, and its relationship to the presence or absence of CRISPR was statistically analyzed. Among the 110 Enterococcus strains, 39 strains (35.45%) contained a complete CRISPR-Cas system, 87 CRISPR arrays were identified, and 62 strains contained Cas gene clusters. The CRISPR system in the Enterococcus genome was mainly type II-A (59.68%), followed by type II-C (33.87%). The phylogenetic analysis of the cas1 gene sequence was basically consistent with the typing of the CRISPR-Cas system. Of the 74 strains included in the study for MLST typing, only 19 (25.68%) were related to CRISPR-Cas typing, while the majority of the strains (74.32%) of MLST typing were associated with the untyped CRISPR system. Additionally, the CRISPR-Cas system may only be related to the carrying rate of some drug-resistant genes and the drug-resistant phenotype. In conclusion, the distribution of the enterococcus CRISPR-Cas system varies greatly among different species and the presence of CRISPR loci reduces the horizontal transfer of some drug resistance genes

    Deciphering a mitochondria-related signature to supervise prognosis and immunotherapy in hepatocellular carcinoma

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    BackgroundHepatocellular carcinoma (HCC) is a major public health problem in humans. The imbalance of mitochondrial function has been discovered to be closely related to the development of cancer recently. However, the role of mitochondrial-related genes in HCC remains unclear.MethodsThe RNA-sequencing profiles and patient information of 365 samples were derived from the Cancer Genome Atlas (TCGA) dataset. The mitochondria-related prognostic model was established by univariate Cox regression analysis and LASSO Cox regression analysis. We further determined the differences in immunity and drug sensitivity between low- and high-risk groups. Validation data were obtained from the International Cancer Genome Consortium (ICGC) dataset of patients with HCC. The protein and mRNA expression of six mitochondria-related genes in tissues and cell lines was verified by immunohistochemistry and qRT-PCR.ResultsThe six mitochondria-related gene signature was constructed for better prognosis forecasting and immunity, based on which patients were divided into high-risk and low-risk groups. The ROC curve, nomogram, and calibration curve exhibited admirable clinical predictive performance of the model. The risk score was associated with clinicopathological characteristics and proved to be an independent prognostic factor in patients with HCC. The above results were verified in the ICGC validation cohort. Compared with normal tissues and cell lines, the protein and mRNA expression of six mitochondria-related genes was upregulated in HCC tissues and cell lines.ConclusionThe signature could be an independent factor that supervises the immunotherapy response of HCC patients and possess vital guidance value for clinical diagnosis and treatment

    Hydrogen Suppresses Hypoxia/Reoxygenation-Induced Cell Death in Hippocampal Neurons Through Reducing Oxidative Stress

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    Background & Aims: Deep hypothermic circulatory arrest (DHCA) is a cerebral protection technique that has been used in the operations involving the aortic arch and brain aneurysm for decades. We previous showed that DHCA treated rats developed a significant oxidative stress and apoptosis in neurons. We here intend to investigate the protective the effect of hydrogen against oxidative stress-induced cell injury and the involved mechanisms using an in vitro experimental model of hypoxia/reoxygenation (H/R) on HT-22 cells. Methods: The model of H/R was established using an airtight culture container and the anaeropack. Measurement of mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) production was used H2DCFDA and JC-1 staining. Western blot was used for the quantification of Akt, p-Akt, Bcl-2, Bax and cleaved caspase-3 proteins. The microRNA (miRNA) profile in hippocampal neurons from rat model of DHCA was determined by miRNA deep sequencing. Results: The elevation of ROS and reduction of MMP were significantly induced by the treatment with hypoxia for 18 h followed by reoxygenation for 6 h. Hydrogen treatment significantly reduced H/R-caused cell death. The levels of p-Akt (Ser 473) and Bcl-2 were significantly increased while Bax and cleaved caspase-3 were decreased by hydrogen treatment on the model of H/R. The expression of miR-200 family was significantly elevated in model of DHCA and H/R. Hydrogen administration inhibited the H/R-induced expression of miR-200 family in HT-22 cells. In addition, inhibition of miR-200 family suppressed H/R-caused cell death through reducing ROS production. Conclusions: These results suggest that H/R causes oxidative stress-induced cell death and that the hydrogen protects against H/R-induced cell death in HT22 cells, in part, due to reducing expression of miR-200 family

    Modeling and Stability Analysis of Pogo Vibration in Liquid-Propellant Rockets with a Two-Propellant System

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