ABSTRACT
OBJECTIVE: How to minimize postoperative pain following knee replacement surgery has been a great challenge. This study was performed to evaluate the effect of applying a topical nonsteroidal anti-inflammatory drug (NSAID) lateral to the incision for postoperative pain following unicompartmental knee arthroplasty (UKA). METHODS: The randomized controlled trial enrolled 100 patients from August 2023 to January 2024. One hundred patients who underwent UKA were randomized into two groups. The intervention group received a topical NSAID lateral to the incision postoperatively, and the control group received a placebo lateral to the incision postoperatively. The primary outcome measures were the amount of opioid consumption and the visual analogue scale (VAS) score (12, 24, 36, 48, and 72 h after operation) for pain. The secondary outcome measures were the American Knee Society Score (AKSS, preoperation and 1-month follow-up after operation), the time of first analgesic demand, side effects of opioids, operation time, postoperative stay, surgery-related complications, and postoperative incision healing grade. Independent sample t test and paired sample t test were used to compare continuous data. Chi-square test and Fisher's precision probability tests were used to analyze the categorical data. RESULTS: Ninety-eight patients (intervention group, 48 patients; control group, 50 patients) were analyzed. Opioid consumption was significantly lower in the intervention group than in the control group during the first 12 h, 12 to 24 h, and 24 to 48 h postoperatively (p < 0.05). The VAS score for pain within 72 h postoperatively was significantly lower in the intervention group than in the control group (p < 0.05). There was no significant difference in the AKSS, operation time, postoperative stay, complications, or postoperative incision healing grade between the two groups. The time of first analgesic demand for patient-controlled analgesia was significantly later in the intervention group than in the control group (p < 0.05). There were fewer side effects of opioids in the intervention group (8.3%) than in the control group (18.0%). CONCLUSION: Postoperative application of topical NSAIDs lateral to the incision is an effective and safe method for pain management after UKA, helping to decrease the pain score and reduce opioid consumption postoperatively with no increase in side effects.
Subject(s)
Administration, Topical , Anti-Inflammatory Agents, Non-Steroidal , Arthroplasty, Replacement, Knee , Pain Measurement , Pain, Postoperative , Humans , Pain, Postoperative/drug therapy , Pain, Postoperative/prevention & control , Arthroplasty, Replacement, Knee/methods , Arthroplasty, Replacement, Knee/adverse effects , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Double-Blind Method , Female , Male , Middle Aged , Aged , Analgesics, Opioid/administration & dosage , Analgesics, Opioid/therapeutic useABSTRACT
BACKGROUND: While previous research has demonstrated potential advantages of unicompartmental knee arthroplasty (UKA) over total knee arthroplasty (TKA), particularly in terms of clinical outcomes such as function and pain relief, the specific impact on health-related quality of life (HRQOL) remains unclear. This systematic review and meta-analysis aim to address this gap by comparing HRQOL outcomes between UKA and TKA, providing valuable insights for clinical decision-making. METHODS: We conducted a literature search in the PubMed, Embase, Cochrane Controlled Register of Trials (CENTRAL), and Web of Science databases up to July 15, 2023. Eligible studies assessed HRQOL using EQ-5D, SF-36, or SF-12 and were assessed for methodological quality using the Newcastle-Ottawa Scale (NOS). RESULTS: Seven eligible studies were included, comprising a total of 64,585 patients with 35,809 undergoing TKA and 28,776 undergoing UKA. Patient age ranged from 52.0 to 67.7 years with an average BMI ranging from 27.2 to 31.0 kg/m2. Follow-up periods ranged from 6 months to 10 years. Five studies (63,829 patients) that evaluated HRQOL using EQ-5D showed significantly better outcomes for UKA compared to TKA (MD -0.04, 95% CI -0.05 to -0.02). Two studies (756 patients) that evaluated HRQOL using SF-36 showed no significant difference between TKA and UKA. Five studies (63,286 patients) that evaluated functional outcomes using Oxford Knee Score (OKS) showed significantly better functional scores for UKA compared to TKA (MD -1.29, 95% CI -1.86 to -0.72). Four studies (24,570 patients) that reported patient satisfaction showed no statistically significant difference between TKA and UKA (MD 0.97, 95% CI 0.90 to 1.05). Further subgroup analysis did not affect the conclusions. CONCLUSIONS: Our meta-analysis suggests that UKA is associated with better HRQOL and knee function, as well as similar patient satisfaction, compared to TKA for patients with unicompartmental osteoarthritis.
Subject(s)
Arthroplasty, Replacement, Knee , Osteoarthritis, Knee , Quality of Life , Humans , Arthroplasty, Replacement, Knee/methods , Osteoarthritis, Knee/surgeryABSTRACT
Acidovorax citrulli populations exhibit genetic and phenotypic variations, particularly in terms of copper tolerance. Group I strains of A. citrulli generally exhibit higher copper tolerance compared to group II strains. This study aims to identify genes involved in copper tolerance to better understand the differences in copper tolerance between group I and group II strains. Representative strains pslb65 (group I) and pslbtw14 (group II) were selected for comparison. Deletion mutants of putative copper-tolerance genes and their corresponding complementary strains were constructed. The copper tolerance of each strain was evaluated using the minimum inhibitory concentration method. The results showed that the copA, copZ, cueR, and cueO genes played major roles in copper tolerance in A. citrulli, while cusC-like, cusA-like, and cusB-like genes had minor effects. The different expression levels of copper-tolerance-related genes in pslb65 and pslbtw14 under copper stress indicated that they had different mechanisms for coping with copper stress. Overall, this study provides insights into the mechanisms of copper tolerance in A. citrulli and highlights the importance of specific genes in copper tolerance.
ABSTRACT
Diabetic retinopathy (DR) is a kind of ocular complication of diabetes, and its degree grade is an essential basis for early diagnosis of patients. Manual diagnosis is a long and expensive process with a specific risk of misdiagnosis. Computer-aided diagnosis can provide more accurate and practical treatment recommendations. In this paper, we propose a multi-view joint learning DR diagnostic model called RT2Net, which integrates the global features of fundus images and the local detailed features of vascular images to reduce the limitations of single fundus image learning. Firstly, the original image is preprocessed using operations such as contrast-limited adaptive histogram equalization, and the vascular structure of the extracted DR image is segmented. Then, the vascular image and fundus image are input into two branch networks of RT2Net for feature extraction, respectively, and the feature fusion module adaptively fuses the feature vectors' output from the branch networks. Finally, the optimized classification model is used to identify the five categories of DR. This paper conducts extensive experiments on the public datasets EyePACS and APTOS 2019 to demonstrate the method's effectiveness. The accuracy of RT2Net on the two datasets reaches 88.2% and 85.4%, and the area under the receiver operating characteristic curve (AUC) is 0.98 and 0.96, respectively. The excellent classification ability of RT2Net for DR can significantly help patients detect and treat lesions early and provide doctors with a more reliable diagnosis basis, which has significant clinical value for diagnosing DR.
Subject(s)
Diabetic Retinopathy , Diagnosis, Computer-Assisted , Diabetic Retinopathy/diagnostic imaging , Diabetic Retinopathy/diagnosis , Humans , Diagnosis, Computer-Assisted/methods , Image Interpretation, Computer-Assisted/methods , Machine LearningABSTRACT
Elucidating the temporal process of immune remodeling under immunosuppressive treatment after liver transplantation (LT) is critical for precise clinical management strategies. Here, we performed a single-cell multi-omics analysis of peripheral blood mononuclear cells (PBMCs) collected from LT patients (with and without acute cellular rejection [ACR]) at 13 time points. Validation was performed in two independent cohorts with additional LT patients and healthy controls. Our study revealed a four-phase recovery process after LT and delineated changes in immune cell composition, expression programs, and interactions along this process. The intensity of the immune response differs between the ACR and non-ACR patients. Notably, the newly identified inflamed NK cells, CD14+RNASE2+ monocytes, and FOS-expressing monocytes emerged as predictive indicators of ACR. This study illuminates the longitudinal evolution of the immune cell landscape under tacrolimus-based immunosuppressive treatment during LT recovery, providing a four-phase framework that aids the clinical management of LT patients.
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OBJECTIVE: This study endeavored to explore the relationship between exosome-derived lncRNA Double Homeobox A Pseudogene 8 (DUXAP8) and Chondroitin Polymerizing Factor 2 (CHPF2), and their roles in the pathogenesis of intracranial aneurysm (IA). METHODS: The shared targeted molecules (DUXAP8 and CHPF2) were detected via GSE122897 and GSE75436 datasets. A total of 312 patients with IAs were incorporated into this study. Exosomes were isolated from serum samples, and their identity was confirmed using Western blotting for exosomal markers (CD9, CD63 and ALIX). Inflammatory responses in IA tissues were evaluated using Hematoxylin-Eosin staining. CHPF2 protein concentration and the expression levels of DUXAP8 and CHPF2 mRNA in exosomal samples were assessed using Immunochemistry (IHC), Western Blotting, and qRT-PCR, respectively. Cell-based assays involving Human Umbilical Vein Endothelial Cells (HuvECs), including transfection with exosomal DUXAP8, Western Blotting, qRT-PCR, and Cell Counting Kit-8, were conducted. Receiver Operating Characteristic (ROC) curves were derived using SPSS. RESULTS: DUXAP8 level affects the level of CHPF2. DUXAP8 expression within exosomes was associated with increased CD9, CD63, ALIX and CHPF2 levels during IA development and inflammatory stress. In HuvECs, transfection with exosomes carrying DUXAP8 siRNA resulted in reduced CHPF2 expression, whereas DUXAP8 mimic increased CHPF2 concentrations. The Area Under the ROC Curve (AUC) for exosomal DUXAP8 expression and CHPF2 levels, and aneurysm size was 0.768 (95% CI, 0.613 to 0.924), 0.937 (95% CI, 0.853 to 1.000), and 0.943 (95% CI, 0.860, 1.000), respectively. CONCLUSION: Exosome-derived DUXAP8 promotes IA progression by affecting CHPF2 expression.
Subject(s)
Exosomes , Intracranial Aneurysm , N-Acetylgalactosaminyltransferases , RNA, Long Noncoding , Humans , Exosomes/genetics , Exosomes/metabolism , Genes, Homeobox , Human Umbilical Vein Endothelial Cells/metabolism , Intracranial Aneurysm/genetics , Intracranial Aneurysm/metabolism , MicroRNAs/metabolism , Pseudogenes , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , N-Acetylgalactosaminyltransferases/metabolismABSTRACT
Neutrophils are increasingly recognized as key players in the tumor immune response and are associated with poor clinical outcomes. Despite recent advances characterizing the diversity of neutrophil states in cancer, common trajectories and mechanisms governing the ontogeny and relationship between these neutrophil states remain undefined. Here, we demonstrate that immature and mature neutrophils that enter tumors undergo irreversible epigenetic, transcriptional, and proteomic modifications to converge into a distinct, terminally differentiated dcTRAIL-R1+ state. Reprogrammed dcTRAIL-R1+ neutrophils predominantly localize to a glycolytic and hypoxic niche at the tumor core and exert pro-angiogenic function that favors tumor growth. We found similar trajectories in neutrophils across multiple tumor types and in humans, suggesting that targeting this program may provide a means of enhancing certain cancer immunotherapies.
Subject(s)
Cellular Reprogramming , Neoplasms , Neovascularization, Pathologic , Neutrophils , Humans , Neoplasms/blood supply , Neoplasms/immunology , Neutrophils/immunology , Proteomics , Cellular Reprogramming/genetics , Cellular Reprogramming/immunology , Neovascularization, Pathologic/genetics , Neovascularization, Pathologic/immunology , Receptors, TNF-Related Apoptosis-Inducing Ligand/immunology , Epigenesis, Genetic , Hypoxia , Transcription, GeneticABSTRACT
PURPOSE: The objective of this study was to investigate the correlation between lower limb alignment and patient outcomes after lateral unicompartmental knee arthroplasty (LUKA). METHODS: In this retrospective study, the information of 51 patients who underwent lateral UKA was collected after an average of 27months of follow-up (13 to 60 months). Evaluation indicators include the AKS and WOMAC score. The Kellgren-Lawrence grade is used to evaluate the severity of osteoarthritis, while the hip-knee-ankle (HKA) angle is utilized to measure the valgus angle of lower limb alignment. RESULT: Patients with postoperative valgus (≥ 3°) alignment had the best outcomes, while those with varus (≤-3°) alignment had the worst outcomes (p < 0.001). Furthermore, it was noted that patients with preoperative mild valgus (≤ 4°) alignment had worse postoperative outcomes than those with severe valgus (≥ 7°) alignment (p < 0.05). The study also revealed a positive correlation between postoperative valgus and WOMAC scores (p < 0.001), whereas a negative correlation was observed between the change in valgus angle and WOMAC scores (p = 0.005). CONCLUSION: During follow-ups, we found that lower limb alignment seems to be an independent predictor of postoperative outcomes. It is recommended that more than 3° of valgus alignment should be maintained after LUKA. Surgeons performing lateral UKA should be cautious of overcorrecting alignment, particularly in patients with preoperative mild valgus alignment.
Subject(s)
Arthroplasty, Replacement, Knee , Osteoarthritis, Knee , Humans , Arthroplasty, Replacement, Knee/adverse effects , Retrospective Studies , Osteoarthritis, Knee/diagnostic imaging , Osteoarthritis, Knee/surgery , Knee Joint/diagnostic imaging , Knee Joint/surgery , Lower Extremity/surgeryABSTRACT
Roundabout guidance receptor 2 (Robo2) is closely related to malignant tumors such as pancreatic cancer and liver fibrosis, but there is no relevant research on the role of Robo2 in HCC. The study will further explore the function and mechanism of Robo2 and its downstream target genes in HCC. Firstly, Robo2 protein levels in human HCC tissues and paired adjacent normal liver tissues were detected. Then we established HepG2 and Huh7 hepatoma cell lines with knock-down Robo2 by transfection with lentiviral vectors, and examined the occurrence of EMT, proliferation and apoptosis abilities in HCC cells by western blot, flow cytometry, wound healing assay and TUNEL staining. Then we verified the interaction between Robo2 and its target gene by Co-IP and immunofluorescence co-staining, and further explored the mechanism of Robo2 and YB-1 by rescue study. The protein expression level of Robo2 in HCC was considerably higher than that in the normal liver tissues. After successfully constructing hepatoma cells with knock-down Robo2, it was confirmed that down-regulated Robo2 suppressed EMT and proliferation of hepatoma cells, and accelerated the cell apoptosis. High-throughput sequencing and validation experiments verified that YB-1 was the downstream target gene of Robo2, and over-expression of YB-1 could reverse the apoptosis induced by Robo2 down-regulation and its inhibitory effect on EMT and proliferation. Robo2 deficiency inhibits EMT and proliferation of hepatoma cells and augments the cell apoptosis by regulating YB-1, thus inhibits the occurrence of HCC and provides a new strategy for the treatment of HCC.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Down-Regulation , Cell Proliferation , Fluorescent Antibody Technique , Gene Expression Regulation, Neoplastic , Cell Line, Tumor , Cell Movement/genetics , Apoptosis/geneticsABSTRACT
1,2-Butanediol (1,2-BDO) is an important platform chemical widely utilized in the synthesis of polyester polyols, plasticizers, cosmetics, and pharmaceuticals. However, no natural metabolic pathway for its biosynthesis has been identified, and biological production of 1,2-BDO from renewable bioresources has not been reported so far. In this study, we designed and experimentally verified a feasible non-natural synthesis pathway for the de novo production of 1,2-BDO from renewable carbohydrates for the first time. This pathway extends the l-threonine synthesis pathway by introducing two artificial metabolic modules to sequentially convert l-threonine into 2-hydroxybutyric acid and 1,2-BDO. Following key enzyme screening and enhancement of l-threonine synthesis module in the chassis microorganism, the best engineered Escherichia coli strain was able to produce 0.15 g/L 1,2-BDO using glucose as the sole carbon source. This work lays the foundation for the bioproduction of 1,2-BDO from renewable resources.
Subject(s)
Escherichia coli , Metabolic Engineering , Escherichia coli/genetics , Escherichia coli/metabolism , Glucose/metabolism , Butylene Glycols/metabolism , Threonine/metabolismABSTRACT
PURPOSE: Ferroptosis acts as an important regulator in diverse human tumors, including the glioma. This study aimed to screen potential ferroptosis-related genes involved in the progression of glioma. MATERIALS AND METHODS: Differently expressed genes (DEGs) were screened based on GSE31262 and GSE12657 datasets, and ferroptosis-related genes were separated. Among the important hub genes in the protein-protein interaction networks, HNRNPM was selected as a research target. Following the knockdown of HNRNPM, the viability, migration, and invasion were detected by CCK8, wound healing, and transwell assays, respectively. The role of HNRNPM knockdown was also verified in a xenograft tumor model in mice. Immunohistochemistry detected the expression levels of HNRNPM and Ki67. Moreover, the ferroptosis was evaluated according to the levels of iron, glutathione peroxidase (GSH), and malondialdehyde (MDA), as well as the expression of PTGS2, GPX4, and FTH1. RESULTS: Total 41 overlapping DEGs relating with ferroptosis and glioma were screened, among which 4 up-regulated hub genes (HNRNPM, HNRNPA3, RUVBL1, and SNRPPF) were determined. The up-regulation of HNRNPM presented a certain predictive value for glioma. In addition, knockdown of HNRNPM inhibited the viability, migration, and invasion of glioma cells in vitro, and also the tumor growth in mice. Notably, knockdown of HNRNPM enhanced the ferroptosis in glioma cells. Furthermore, HNRNPM was positively associated with SMARCA4 in glioma. CONCLUSIONS: Knockdown of HNRNPM inhibits the progression of glioma via inducing ferroptosis. HNRNPM is a promising molecular target for the treatment of glioma via inducing ferroptosis. We provided new insights of glioma progression and potential therapeutic guidance.
Subject(s)
Ferroptosis , Glioma , Humans , Animals , Mice , Ferroptosis/genetics , Glioma/genetics , Cyclooxygenase 2 , Disease Models, Animal , Heterografts , DNA Helicases , Nuclear Proteins , Transcription Factors , Heterogeneous-Nuclear Ribonucleoprotein Group M , ATPases Associated with Diverse Cellular Activities , Carrier ProteinsABSTRACT
Introduction: Sepsis is a life-threatening disease that damages multiple organs and induced by the host's dysregulated response to infection with high morbidity and mortality. Heart remains one of the most vulnerable targets of sepsis-induced organ damage, and sepsis-induced cardiomyopathy (SIC) is an important factor that exacerbates the death of patients. However, the underlying genetic mechanism of SIC disease needs further research. Methods: The transcriptomic dataset, GSE171564, was downloaded from NCBI for further analysis. Gene expression matrices for the sample group were obtained by quartile standardization and log2 logarithm conversion prior to analysis. The time series, protein-protein interaction (PPI) network, and functional enrichment analysis via Gene Ontology and KEGG Pathway Databases were used to identify key gene clusters and their potential interactions. Predicted miRNA-mRNA relationships from multiple databases facilitated the construction of a TF-miRNA-mRNA regulatory network. In vivo experiments, along with qPCR and western blot assays, provided experimental validation. Results: The transcriptome data analysis between SIC and healthy samples revealed 221 down-regulated, and 342 up-regulated expressed genes across two distinct clusters. Among these, Tpt1, Mmp9 and Fth1 were of particular significance. Functional analysis revealed their role in several biological processes and pathways, subsequently, in vivo experiments confirmed their overexpression in SIC samples. Notably, we found TPT1 play a pivotal role in the progression of SIC, and silencing TPT1 showed a protective effect against LPS-induced SIC. Conclusion: In our study, we demonstrated that Tpt1, Mmp9 and Fth1 have great potential to be biomarker of SIC. These findings will facilitated to understand the occurrence and development mechanism of SIC.
Subject(s)
Cardiomyopathies , MicroRNAs , Sepsis , Humans , Matrix Metalloproteinase 9/genetics , Gene Regulatory Networks , MicroRNAs/genetics , Cardiomyopathies/etiology , Sepsis/complications , RNA, Messenger/geneticsABSTRACT
BACKGROUND & AIMS: Pien Tze Huang (PZH) is a well-established traditional medicine with beneficial effects against inflammation and cancer. We aimed to explore the chemopreventive effect of PZH in colorectal cancer (CRC) through modulating gut microbiota. METHODS: CRC mouse models were established by azoxymethane plus dextran sulfate sodium treatment or in Apcmin/+ mice treated with or without PZH (270 mg/kg and 540 mg/kg). Gut barrier function was determined by means of intestinal permeability assays and transmission electron microscopy. Fecal microbiota and metabolites were analyzed by means of metagenomic sequencing and liquid chromatography mass spectrometry, respectively. Germ-free mice or antibiotic-treated mice were used as models of microbiota depletion. RESULTS: PZH inhibited colorectal tumorigenesis in azoxymethane plus dextran sulfate sodium-treated mice and in Apcmin/+ mice in a dose-dependent manner. PZH treatment altered the gut microbiota profile, with an increased abundance of probiotics Pseudobutyrivibrio xylanivorans and Eubacterium limosum, while pathogenic bacteria Aeromonas veronii, Campylobacter jejuni, Collinsella aerofaciens, and Peptoniphilus harei were depleted. In addition, PZH increased beneficial metabolites taurine and hypotaurine, bile acids, and unsaturated fatty acids, and significantly restored gut barrier function. Transcriptomic profiling revealed that PZH inhibited PI3K-Akt, interleukin-17, tumor necrosis factor, and cytokine-chemokine signaling. Notably, the chemopreventive effect of PZH involved both microbiota-dependent and -independent mechanisms. Fecal microbiota transplantation from PZH-treated mice to germ-free mice partly recapitulated the chemopreventive effects of PZH. PZH components ginsenoside-F2 and ginsenoside-Re demonstrated inhibitory effects on CRC cells and primary organoids, and PZH also inhibited tumorigenesis in azoxymethane plus dextran sulfate sodium-treated germ-free mice. CONCLUSIONS: PZH manipulated gut microbiota and metabolites toward a more favorable profile, improved gut barrier function, and suppressed oncogenic and pro-inflammatory pathways, thereby suppressing colorectal carcinogenesis.
Subject(s)
Colorectal Neoplasms , Gastrointestinal Microbiome , Mice , Animals , Signal Transduction , Dextran Sulfate/toxicity , Phosphatidylinositol 3-Kinases/metabolism , Apoptosis , Medicine, Traditional , Colorectal Neoplasms/chemically induced , Colorectal Neoplasms/prevention & control , Colorectal Neoplasms/metabolism , Carcinogenesis , Azoxymethane/toxicityABSTRACT
Acidovorax citrulli, the causative agent of bacterial fruit blotch, can be divided into two main groups based on factors such as pathogenicity and host species preference. PilA is an important structural and functional component of type IV pili (T4P). Previous studies have found significant differences in pilA DNA sequences between group I and group II strains of A. citrulli. In this study, we characterized pilA in the group I strain pslb65 and the group II strain Aac5. pilA mutants, complementation strains, and cross-complementation strains were generated, and their biological phenotypes were analyzed to identify functional differences between pilA in the two groups. pilA deletion mutants (pslb65-ΔpilA and Aac5-ΔpilA) showed significantly reduced pathogenicity compared with the wild-type (WT) strains; pslb65-ΔpilA also completely lost twitching motility, whereas Aac5-ΔpilA only partially lost motility. In King's B medium, there were no significant differences in biofilm formation between pslb65-ΔpilA and WT pslb65, but Aac5-ΔpilA showed significantly reduced biofilm formation compared to WT Aac5. In M9 minimal medium, both mutants showed significantly lower biofilm formation compared to the corresponding WT strains, although biofilm formation was recovered in the complementation strains. The biofilm formation capacity was somewhat recovered in the cross-complementation strains but remained significantly lower than in the WT strains. The interspecies competitive abilities of pslb65-ΔpilA and Aac5-ΔpilA were significantly lower than in the WT strains; Aac5-ΔpilA was more strongly competitive than pslb65-ΔpilA, and the complementation strains recovered competitiveness to WT levels. Furthermore, the cross-complementation strains showed stronger competitive abilities than the corresponding WT strains. The relative expression levels of genes related to T4P and the type VI secretion system were then assessed in the pilA mutants via quantitative PCR. The results showed significant differences in the relative expression levels of multiple genes in pslb65-ΔpilA and Aac5-ΔpilA compared to the corresponding WT stains. This indicated the presence of specific differences in pilA function between the two A. citrulli groups, but the regulatory mechanisms involved require further study.
ABSTRACT
Bacterial fruit blotch (BFB), caused by Acidovorax citrulli, severely damages watermelon, melon, and other cucurbit crops worldwide. Nitrogen, one of the most important limiting elements in the environment, is necessary for the growth and reproduction of bacteria. As a nitrogen-regulating gene, ntrC plays an important role in maintaining bacterial nitrogen utilization and biological nitrogen fixation. However, the role of ntrC has not been determined for A. citrulli. In this study, we constructed a ntrC deletion mutant and a corresponding complementary strain in the background of the A. citrulli wild-type strain, Aac5. Through phenotype assays and qRT-PCR analysis, we investigated the role of ntrC in A. citrulli in nitrogen utilization, stress tolerance, and virulence against watermelon seedlings. Our results showed that the A. citrulli Aac5 ntrC deletion mutant lost the ability to utilize nitrate. The ntrC mutant strain also exhibited significantly decreased virulence, in vitro growth, in vivo colonization ability, swimming motility, and twitching motility. In contrast, it displayed significantly enhanced biofilm formation and tolerance to stress induced by oxygen, high salt, and copper ions. The qRT-PCR results showed that the nitrate utilization gene nasS; the Type III secretion system-related genes hrpE, hrpX, and hrcJ; and the pili-related gene pilA were significantly downregulated in the ntrC deletion mutant. The nitrate utilization gene nasT, and the flagellum-related genes flhD, flhC, fliA, and fliC were significantly upregulated in the ntrC deletion mutant. The expression levels of ntrC gene in the MMX-q and XVM2 media were significantly higher than in the KB medium. These results suggest that the ntrC gene plays a pivotal role in the nitrogen utilization, stress tolerance, and virulence of A. citrulli.
ABSTRACT
A novel process for simultaneous production of furfural and pretreatment of oil palm empty fruit bunch (EFB) by dilute acid pre-hydrolysis was developed based on non-isothermal kinetic modeling. Mass transfer analysis suggested that the internal diffusion could be neglected as diffusion time of sulfuric acid in EFB particles was significantly shorter than the pre-hydrolysis period, whereas the heating stage could not be neglected due to a significant part of xylan was solubilized at the stage. A strategy for increasing furfural yield was developed by intermittent discharging of steam, resulting in 71.4 % furfural yield. The pretreated solids showed good enzymatic digestibility. 136.3 g/L glucose corresponding to 81.6 % yield was obtained by high-solid loading hydrolysis. 95.4 g furfural and 212 g glucose could be obtained from 1 kg dry EFB. Therefore, non-isothermal effects on polysaccharide hydrolysis and pentose decomposition should be considered carefully for an efficient process design of EFB biorefining.
Subject(s)
Arecaceae , Furaldehyde , Fruit , Hydrolysis , Biomass , Acids , Glucose , Palm OilABSTRACT
Watermelon diseases caused by pathogenic bacteria were endemic in Liaoning and Jilin Provinces from 2019 to 2020 in China, resulting in serious economic losses to the watermelon industry. This study characterized 56 strains isolated from symptomatic watermelon leaves collected from Liaoning and Jilin Provinces. Through morphological observation, 16S rRNA and gyrB sequence analysis, and BIOLOG profiles, the pathogen was identified as Pseudomonas syringae. In China, the watermelon disease caused by P. syringae was reported for the first time. The multilocus sequence analysis showed that the isolated strains belonged to three different clades within P. syringae phylogroup 2. Interestingly, most of them (79%) belonged to clade 2a, 14% were clade 2b, and 7% were clade 2d. This indicates that bacterial leaf spot outbreaks of watermelon in China were caused by multiple sources and mainly by P. syringae clade 2a.
Subject(s)
Citrullus , Citrullus/genetics , RNA, Ribosomal, 16S/genetics , Plant Diseases/microbiology , Phylogeny , Pseudomonas syringae , ChinaABSTRACT
Background: The initial dose of tacrolimus after liver transplantation (LT) is critical for rapidly achieving the steady state of the drug concentration, minimizing the potential adverse reactions and warranting long-term patient prognosis. We aimed to develop and validate a genotype-guided model for determining personalized initial dose of tacrolimus. Methods: By combining pharmacokinetic modeling, pharmacogenomic analysis and multiple statistical methods, we developed a genotype-guided model to predict individualized tacrolimus initial dose after LT in the discovery (n = 150) and validation cohorts (n = 97) respectively. This model was further validated in a prospective, randomized and single-blind clinical trial from August, 2021 to February, 2022 (n = 40, ChiCTR2100050288). Findings: Our model included donor's and recipient's genotypes, recipient's weight and total bilirubin, which achieved an area under the curve of receiver operating characteristic curve (AUC of ROC) of 0.88 and 0.79 in the discovery and validation cohorts, respectively. We found that patients who were given tacrolimus within the recommended concentration range (RCR) (4-10 ng/mL), the new-onset metabolic syndromes are lower, especially for new-onset diabetes (p = 0.043). In the clinical trial, compared to those in experience-based (EB) group, patients in the model-based (MB) group were more likely to achieving the RCR (75% vs 40%, p = 0.025) with a more variable individualized dose (0.023-0.096 mg/kg/day vs 0.045-0.057 mg/kg/day). Moreover, significantly fewer medication adjustments were required for the MB group than the EB group (2.75 ± 2.01 vs 6.05 ± 3.35, p = 0.001). Interpretation: Our genotype-based model significantly improved the initial dosing accuracy of tacrolimus and reduced the number of medication adjustments, which are critical for improving the prognosis of LT patients. Funding: National Natural Science Foundation of China, Shanghai three-year action plan, National Science and Technology Major Project of China.
ABSTRACT
The fastest-growing bacterium Vibrio natriegens is a highly promising next-generation workhorse for molecular biology and industrial biotechnology. In this work, we described the workflows for developing genome-scale metabolic models and genome-editing protocols for engineering Vibrio natriegens. A case study for metabolic engineering of Vibrio natriegens for the production of 1,3-propanediol was also presented.
Subject(s)
Metabolic Engineering , Vibrio , Gene Editing , Propylene Glycols , Vibrio/genetics , Vibrio/metabolismABSTRACT
Deconstruction of cell wall structure is important for biorefining of lignocellulose to produce various biofuels and chemicals. Oxidative delignification is an effective way to increase the enzymatic digestibility of cellulose. In this work, the current research progress on conventional oxidative pretreatment including wet oxidation, alkaline hydrogen peroxide, organic peracids, Fenton oxidation, and ozone oxidation were reviewed. Some recently developed novel technologies for coupling pretreatment and direct biomass-to-electricity conversion with recyclable oxidants were also introduced. The primary mechanism of oxidative pretreatment to enhance cellulose digestibility is delignification, especially in alkaline medium, thus eliminating the physical blocking and non-productive adsorption of enzymes by lignin. However, the cost of oxidative delignification as a pretreatment is still too expensive to be applied at large scale at present. Efforts should be made particularly to reduce the cost of oxidants, or explore valuable products to obtain more revenue.