Identification of KRAS mutation-associated gut microbiota in colorectal cancer and construction of predictive machine learning model.

Gut microbiota has demonstrated an increasingly important role in the onset and development of colorectal cancer (CRC). Nonetheless, the association between gut microbiota and KRAS mutation in CRC remains enigmatic. We conducted 16S rRNA sequencing on stool samples from 94 CRC patients and employed the linear discriminant analysis effect size algorithm to identify distinct gut microbiota between KRAS mutant and KRAS wild-type CRC patients. Transcriptome sequencing data from nine CRC patients were transformed into a matrix of immune infiltrating cells, which was then utilized to explore KRAS mutation-associated biological functions, including Gene Ontology items and Kyoto Encyclopedia of Genes and Genomes pathways. Subsequently, we analyzed the correlations among these KRAS mutation-associated gut microbiota, host immunity, and KRAS mutation-associated biological functions. At last, we developed a predictive random forest (RF) machine learning model to predict the KRAS mutation status in CRC patients, based on the gut microbiota associated with KRAS mutation. We identified a total of 26 differential gut microbiota between both groups. Intriguingly, a significant positive correlation was observed between Bifidobacterium spp. and mast cells, as well as between Bifidobacterium longum and chemokine receptor CX3CR1. Additionally, we also observed a notable negative correlation between Bifidobacterium and GOMF:proteasome binding. The RF model constructed using the KRAS mutation-associated gut microbiota demonstrated qualified efficacy in predicting the KRAS phenotype in CRC. Our study ascertained the presence of 26 KRAS mutation-associated gut microbiota in CRC and speculated that Bifidobacterium may exert an essential role in preventing CRC progression, which appeared to correlate with the upregulation of mast cells and CX3CR1 expression, as well as the downregulation of GOMF:proteasome binding. Furthermore, the RF model constructed on the basis of KRAS mutation-associated gut microbiota exhibited substantial potential in predicting KRAS mutation status in CRC patients.IMPORTANCEGut microbiota has emerged as an essential player in the onset and development of colorectal cancer (CRC). However, the relationship between gut microbiota and KRAS mutation in CRC remains elusive. Our study not only identified a total of 26 gut microbiota associated with KRAS mutation in CRC but also unveiled their significant correlations with tumor-infiltrating immune cells, immune-related genes, and biological pathways (Gene Ontology items and Kyoto Encyclopedia of Genes and Genomes pathways). We speculated that Bifidobacterium may play a crucial role in impeding CRC progression, potentially linked to the upregulation of mast cells and CX3CR1 expression, as well as the downregulation of GOMF:Proteasome binding. Furthermore, based on the KRAS mutation-associated gut microbiota, the RF model exhibited promising potential in the prediction of KRAS mutation status for CRC patients. Overall, the findings of our study offered fresh insights into microbiological research and clinical prediction of KRAS mutation status for CRC patients.

Regulation of quorum sensing activities by the stringent response gene rsh in sphingomonads is species-specific and culture condition dependent.

Stringent response and quorum sensing (QS) are two essential mechanisms that control bacterial global metabolism for better survival. Sphingomonads are a clade of bacteria that survive successfully in diverse ecosystems. In silico survey indicated that 36 out of 79 investigated sphingomonads strains contained more than one luxI homolog, the gene responsible for the biosynthesis of QS signal acyl homoserine lactones (AHLs). Investigation of the regulatory effects of the stringent response gene rsh on QS related bioactivities were carried out using rsh mutants of Sphingobium japonicum UT26 and Sphingobium sp. SYK-6, both had three luxI homologs. Results indicated that deletion of rsh upregulated the overall production of AHLs and extracellular polymeric substances (EPS) in both UT26 and SYK-6 in rich medium, but affected expressions of these luxI/luxR homologs in different ways. In the poor medium (1% LB), rsh mutant of SYK-6 significantly lost AHLs production in broth cultivation but not in biofilm cultivation. The regulatory effects of rsh on QS activities were growth phase dependent in UT26 and culture condition dependent in SYK-6. Our results demonstrated the negative regulatory effect of rsh on QS activities in sphingomonads, which were very different from the positive effect found in sphingomonads containing only one luxI/R circuit. This study extends the current knowledge on the intricate networks between stringent response and QS system in sphingomonads, which would help to understand their survival advantage.

Three once-weekly intra-articular injections of Hylan G-F 20 significantly improve pain relief compared with placebo in patients with chronic idiopathic knee osteoarthritis: a single-centre, evaluator-blinded and patient-blinded, randomized controlled trial.

Background: Clinical trials on the use of viscosupplementation with hyaluronic acid (HA) in patients with knee osteoarthritis (KOA) are inconsistent, making it challenging to determine its value in clinical practice. One issue is the availability of various HA products on the market; differences in their chemical features can impact patient outcomes. Herein, we assess the efficacy and safety of three once-weekly intra-articular (IA) injections of Hylan G-F 20, a high-molecular-weight and highly crosslinked HA product, in patients with KOA. We hypothesized that Hylan G-F 20 would provide significant pain relief with no increased safety risk compared with IA saline (placebo). Methods: This was a 26-week, patient-blinded and evaluator-blinded, single-centre, randomized placebo- controlled trial. Men or women ≥18 years of age with Larsen grade II or III KOA were included. Patients received IA injections of either Hylan G-F 20 or placebo once a week for 3 weeks. The primary endpoints were the week 12 and 26 visits. Primary efficacy outcomes included visual analogue scale (VAS) pain scores, patient activity level and an overall assessment of clinical condition. Secondary outcomes included adverse events (AEs) that emerged during treatment. The primary analysis included the intention-to-treat population. An alpha level of 0.05 was used in the statistical analysis. Results: Thirty patients were included in the intention-to-treat population (15 per group). All efficacy outcomes were statistically significant in favour of Hylan G-F 20, except night pain and inactivity stiffness, for both patient- assessed (all p=0.0001 at week 12) and evaluator-assessed (all p=0.0001 at week 12 and p=0.0004-0.0180 at week 26) measurements. There was also a greater proportion of symptom-free patients and those with a >50% improvement in their VAS scores, except night pain, in the Hylan G-F 20 group (p=0.001-0.003 in patient-assessed scores and p<0.0001 to 0.002 in evaluator-assessed scores at week 12). Two patients, one in each group, experienced an AE; no sequelae occurred, and no special treatment was required for either AE. No patients withdrew from the study prematurely due to an AE. Conclusion: In patients with chronic idiopathic KOA, Hylan G-F 20 provides significant improvements in pain relief compared with placebo with no added safety concerns.

The moderated-mediation role of risk perception and intolerance of uncertainty in the association between residual symptoms and psychological distress: a cross-sectional study after COVID-19 policy lifted in China.

BACKGROUND: A considerable number of individuals infected with COVID-19 experience residual symptoms after the acute phase. However, the correlation between residual symptoms and psychological distress and underlying mechanisms are scarcely studied. We aim to explore the association between residual symptoms of COVID-19 and psychological distress, specifically depression, anxiety, and fear of COVID-19, and examine the role of risk perception and intolerance of uncertainty in the association. METHODS: A cross-sectional survey was conducted by online questionnaire-based approach in mid-January 2023. Self-reported demographic characteristics, COVID-19-related information, and residual symptoms were collected. Depression, anxiety, fear, risk perception and intolerance of uncertainty were evaluated using the Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), Fear of COVID-19 Scale (FCV-19S), COVID-19 Risk Perception Scale and Intolerance of Uncertainty Scale-12 (IUS-12), respectively. Linear regression analyses were conducted to explore the associations. A moderated mediation model was then constructed to examine the role of risk perception of COVID-19 and intolerance of uncertainty in the association between residual symptoms and psychological distress. RESULTS: 1735 participants effectively completed the survey. 34.9% of the patients experienced residual symptoms after acute phase of COVID-19. Psychological distress was markedly increased by COVID-19 infection, while residual symptoms had a significant impact on psychological distress (Ps < 0.001), including depression (ß = 0.23), anxiety (ß = 0.21), and fear of COVID-19 (ß = 0.14). Risk perception served as a mediator between residual symptoms and all forms of psychological distress, while intolerance of uncertainty moderated the effect of risk perception on depression and anxiety. CONCLUSION: A considerable proportion of patients experience residual symptoms after acute phase of COVID-19, which have a significant impact on psychological distress. Risk perception and intolerance of uncertainty play a moderated-mediation role in the association between residual symptoms and depression/anxiety. It highly suggests that effective treatment for residual symptoms, maintaining appropriate risk perception and improving intolerance of uncertainty are critical strategies to alleviate COVID-19 infection-associated psychological distress.

Perceived risk of COVID-19 hurts mental health: the mediating role of fear of COVID-19 and the moderating role of resilience.

BACKGROUND: Depression and anxiety have been found prevalent during all phases of the COVID-19 pandemic. In late December 2022, almost all COVID-19 control measures were lifted in China, leading to a surge in COVID-19 infections. The public's perceived risk and fear of COVID-19 would be increased. This study aims to examine the prevalence of depression and anxiety in the Chinese general population and explores the mediating role of fear of COVID-19 between COVID-19 perceived risk and depression/anxiety and the moderating role of resilience between fear of COVID-19 and depression/anxiety. METHODS: A cross-sectional online survey was conducted in Wenzhou, China, immediately following almost all COVID-19 control measures lifted. The 9-item Patient Health Questionnaire (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), the COVID-19 Risk Perception Scale, the Fear of COVID-19 Scale, and the Connor-Davidson Resilience Scale (CD-RISC) were used to evaluate depression, anxiety, COVID-19 perceived risk, fear of COVID-19, and resilience, respectively. Structural Equation Modeling (SEM) with Maximum Likelihood (ML) estimator and adjusted for significant background factors was performed to test the moderated mediation. Data obtained from 935 participants were analyzed. RESULTS: The prevalence of moderate to severe depression and anxiety was 23.7% and 9.5%, respectively. The present study revealed positive associations among COVID-19 perceived risk, fear of COVID-19 and depression/anxiety, and negative associations between resilience and fear of COVID-19/depression/anxiety. Fear of COVID-19 partially mediated the association between COVID-19 perceived risk and depression/anxiety. Furthermore, resilience significantly moderated the association between fear of COVID-19 and depression/anxiety. Two moderated mediation models were constructed. CONCLUSION: Depression and anxiety were prevalent among Chinese adults during the final phase of the pandemic in China. The significant mediation role of fear of COVID-19 implies that reducing fear of COVID-19 may effectively alleviate depression and anxiety symptoms. Moreover, enhancing public resilience during an epidemic crisis is crucial for promoting mental health.

Three Weekly Intra-Articular Injections of Hylan G-F 20 vs Arthrocentesis in Patients with Chronic Idiopathic Knee Osteoarthritis: A Multicenter, Evaluator- and Patient-Blinded, Randomized Controlled Trial.

Background: Knee osteoarthritis is a leading cause of disability worldwide. Symptoms can vary over time, leading to episodes of worsened symptoms known as flares. Intra-articular injection of hyaluronic acid has demonstrated long-term symptomatic relief in the broader knee osteoarthritis population, although its use in the flare population has not been extensively examined. Objective: To assess the efficacy and safety of 3 once-weekly intra-articular injections of hylan G-F 20 (as single and repeat courses) in patients with chronic knee osteoarthritis, including a subpopulation that experienced flare. Methods: Prospective randomized controlled, evaluator- and patient-blinded, multicenter trial with 2 phases: hylan G-F 20 vs arthrocentesis only (control) and 2 courses vs single-course hylan G-F 20. Primary outcomes were visual analog scale (0-100 mm) pain scores. Secondary outcomes included safety and synovial fluid analysis. Results: Ninety-four patients (104 knees) were enrolled in Phase I, with 31 knees representing flare patients. Seventy-six patients (82 knees) were enrolled in Phase II. Long-term follow-up was 26 to 34 weeks. In flare patients, hylan G-F 20 showed significantly more improvement than the controls for all primary outcomes except pain at night (P = 0.063). Both 1 and 2 courses of hylan G-F 20 showed significant improvements from baseline for primary outcomes with no differences in efficacy between groups in the intention-to-treat population at the end of Phase II. Two courses of hylan G-F 20 showed better improvement in pain with motion (P = 0.0471) at long-term follow-up. No general side effects were reported, and local reactions (pain/swelling of the injected joint) resolved within 1 to 2 weeks. Hylan G-F 20 was also associated with reduced effusion volume and protein concentration. Conclusions: Hylan G-F 20 significantly improves pain scores vs arthrocentesis in flare patients with no safety concerns. A repeat course of hylan G-F 20 was found to be well tolerated and efficacious.

The stringent response gene rsh plays multiple roles in Novosphingobium pentaromativorans US6-1's accommodation to different environmental pollutants: Phenanthrene, copper and nZVI.

The rsh based stringent response system is widely employed by bacteria to cope with environmental stresses. However, how does the stringent response involve in bacterial accommodation to environmental pollutant is largely unexplored. In this study, to comprehensively understand the roles of rsh in Novosphingobium pentaromativorans US6-1's metabolism and accommodation to different pollutants, three distinct pollutants, phenanthrene, copper and nanoparticulated zero valent iron (nZVI) were selected as exposure substances. Results indicated that rsh played important roles in US6-1's multiplication and metabolism, including survival rate at stationary phase, amino acid and nucleotide metabolism, extracellular polymeric substance (EPS) production, redox homeostasis, etc. The deletion of rsh affected phenanthrene removal rates through regulating the multiplication of US6-1 and increasing the expression of degradation related genes. The rsh mutant showed higher resistance to copper than the wild type, largely due to higher EPS production and enhanced expression of copper resistance related genes. Finally, the rsh based stringent response helped maintain the redox homeostasis when US6-1 confronted nZVI particles that exerted oxidative stress, thereby improving the survival rate. Overall, this study provides firsthand data that rsh plays multiple roles in US6-1's accommodation to environmental pollutants. The stringent response system could be a powerful tool for environmental scientists and engineers to harness bacterial activities for bioremediation purposes.

Mutations in lysine methyltransferase 2C and PEG3 are associated with tumor mutation burden, prognosis, and antitumor immunity in pancreatic adenocarcinoma patients.

Background: As a common cancer-related death worldwide, pancreatic adenocarcinoma (PAAD) has significantly increased mortality in recent years. In recent years, tumor mutation burden (TMB) has been regarded as the most popular biomarker for PAAD immunotherapy. However, it remains unclear which gene mutations affect TMB and immune response in pancreatic adenocarcinoma. Methods: The somatic mutation images of PAAD samples were downloaded from The Cancer Genome Atlas (TCGA) and the International Cancer Genome Consortium (ICGC). Based on the expression data of the TCGA and IGCC cohorts, various bioinformatics algorithms are used for evaluating the prognostic value and functional annotation of some frequently somatically mutated genes. Furthermore, the correlation between gene mutation and tumor immunity was also evaluated. Results: The results showed that lysine methyltransferase 2C (KMT2C) and paternally expressed 3 (PEG3) are frequently mutated genes in PAAD. Patients with KMT2C and PEG3 mutations have higher TMB severity and a lousy prognosis. In addition, the mutations of KMT2C and PEG3 genes positively regulate the metabolic and protein-related pathways in PAAD. Meanwhile, significant differences in the composition of the immune cells were observed for KMT2C and PEG3 mutations PAAD patients, for providing additional guidelines for antitumor treatments in various KMT2C and PEG3 mutation states in PAAD. Conclusion: This study reveals that KMT2C and PEG3 mutation may serve as biomarkers for predicting prognosis and guiding anti-PAAD immunotherapy for PAAD patients.

Opposite selection effects of nZVI and PAHs on bacterial community composition revealed by universal and sphingomonads-specific 16S rRNA primers.

Next-generation sequencing method employing the sphingomonads-specific and universal 16s rRNA primers were applied to analyze the response of soil bacterial community to continuous stress of nanoscale zero-valent iron (nZVI) and/or polycyclic aromatic hydrocarbons (PAHs) under suspended conditions. The group specific primer greatly improves taxonomic resolution, the overall OTU numbers increased from 12 by universal primer to 42 by sphingomonads-specific primer. It was found that nZVI and PAHs had opposite selection effects on bacterial community composition, furthermore, the abundance of Sphingopyxis was positively related to nZVI while negatively related to PAHs, whereas abundances of Sphingobium and Sphingosinicella were positively related to PAHs (p < 0.01). The improved taxonomic resolution helps identify the potential keystone taxa, which provides valuable information for future bioremediation technology such as synthetic microbiome.

Adherence to the OARSI recommendations for designing, conducting, and reporting of clinical trials in knee osteoarthritis: a targeted literature review.

BACKGROUND: The Osteoarthritis Research Society International (OARSI) updated their guideline for clinical trials on knee osteoarthritis (KOA) in 2015, which contains recommendations for the conduct, design, and reporting of clinical trials. The purpose of this study was to assess the quality of clinical trials published between 2010 and 2020 investigating intra-articular interventions in patients with KOA using the OARSI recommendations. METHODS: A targeted literature review was conducted to identify randomized controlled trials in patients with KOA receiving intra-articular interventions, published between 2010 and 2020. Included studies were assessed using the OARSI recommendations. For a comparison between the time periods before and after the introduction of the new OARSI recommendations, the year 2016 was selected as the cut-off. RESULTS: One hundred forty-eight publications, representing 139 unique trials, were included in this review. Included studies adhered to between 9 and 24 recommendations (median: 19). The highest increase in adherence from studies published in 2016 or earlier compared to after 2016 was seen in the reporting and registration of trials and the use of structural outcome measures. Overall, adherence to the recommendations related to the collection of biochemical biomarkers and the use of structural outcome measures remained low. CONCLUSION: An improvement can be made in the conduct, design, and reporting of clinical trials for intra-articular therapies in KOA. Despite proper guidelines, quality of clinical trials varies, and the methodological deficiencies found are preventable and can be corrected. The quality of research should be considered when making treatment decisions for patients with KOA in clinical practice.

Intra-articular placebo effect in the treatment of knee osteoarthritis: a survey of the current clinical evidence.

Knee osteoarthritis (KOA) is a debilitating disease characterized by chronic pain, stiffness, and decreased mobility. Intra-articular injectable therapies show good clinical efficacy in improving symptoms; however, these therapies and their comparators (intra-articular saline) have been associated with a large underlying placebo effect. We aimed to describe the existing evidence on the challenges, hypotheses, and potential solutions to mitigate the intra-articular placebo effect in clinical trials in KOA. A targeted literature review was conducted by searching Embase, MEDLINE®, and CENTRAL using predefined study selection criteria. All eligible studies identified were extracted for relevant data, and results were narratively summarized. Forty-three studies were included following screening. Challenges associated with the intra-articular placebo effect included its ability to mask the comparative efficacy of active treatments in trials (n = 7 studies), long-lasting effects (up to 6 months; n = 3), and substantial variation of placebo effect sizes across populations (n = 3). Hypotheses for the mechanism of the placebo effect included aspiration of synovial fluid during administration (n = 6) and dilution of inflammatory mediators (n = 2). Factors affecting the placebo effect size were more invasive routes of administration (e.g., injection versus oral; n = 4) and patient expectations (n = 2). Proposed solutions included the suggestion for readers to weigh the relevance of clinical trial evidence against the presence of large underlying placebo effects (n = 9), discontinuation of intra-articular saline as an appropriate placebo (n = 5), and inclusion of 'no treatment' or sham injection as a control (n = 4). The intra-articular placebo effect is a well-documented occurrence in KOA clinical trials, and it is suggested that it be accounted for when designing randomized controlled trials. Awareness and understanding of the intra-articular placebo effect in KOA are required for fair interpretation of clinical trial evidence.

Analysis of Bleeding Site to Identify Associated Risk Factors of Intractable Epistaxis.

INTRODUCTION: Intractable epistaxis refers to deep occult bleeding and uncontrolled persistent bleeding. Effective treatment can only be implemented if the bleeding site is quickly identified and the underlying disease controlled. OBJECTIVE: The relationship between the bleeding site and the pathogenic factors of intractable epistaxis was analyzed to further strengthen the prevention and treatment of intractable epistaxis by outpatient doctors, family doctors and otolaryngologists. Through accurate search and minimally invasive hemostasis, it helped optimize the treatment plan for intractable epistaxis. METHODS: This study retrospectively analyzed the clinical data of 90 patients with intractable epistaxis who were admitted to hospital from January 2016 to December 2017. Chi-square test was used to analyze the relationship between intractable epistaxis site with underlying disease, gender and age. RESULTS: The distribution of intractable epistaxis was associated with hypertension (χ 2=13.76, P=0.017). The incidence of hypertension was the highest in the olfactory sulcus of the middle turbinate region at about 60%. In addition, age was also identified as a factor that affects the distribution of intractable epistaxis (χ 2=21.95, P=0.02). The incidence of intractable epistaxis on the vault of inferiornasal meatus region was highest (63%) in young patients. On the other hand, the olfactory sulcus of the middle turbinate region accounted for the highest incidence in the middle-aged and elderly group (66.7%). There was no obvious relation between the bleeding site of intractable epistaxis with diabetes, cardiovascular disease, chronic sinusitis and allergic rhinitis. CONCLUSION: The bleeding site of intractable epistaxis is related to hypertension and age. This may improve the identification of the site of intractable epistaxis for timely implementation of treatment and can further strengthen the prevention and treatment of intractable epistaxis in outpatients or family doctors.

Intraarticular Hyaluronic Acid Preparations for Knee Osteoarthritis: Are Some Better Than Others?

OBJECTIVE: This literature review summarizes evidence on the safety and efficacy of intraarticular hyaluronic acid (IAHA) preparations approved in the United States for the treatment of osteoarthritis of the knee. DESIGN: A systematic literature search was performed in PubMed, Ovid MEDLINE, and SCOPUS databases. Only studies in which clinical outcomes of individual IAHA preparations alone could be assessed when compared to placebo, no treatment, other standard knee osteoarthritis treatments, and IAHA head-to-head studies were selected. RESULTS: One hundred nine articles meeting our inclusion criteria were identified, including 59 randomized and 50 observational studies. Hylan G-F 20 has been the most extensively studied preparation, with consistent results confirming efficacy in placebo-controlled studies. Efficacy is also consistently reported for Supartz, Monovisc, and Euflexxa, but not for Hyalgan, Orthovisc, and Durolane. In the head-to-head trials, high-molecular-weight (MW) Hylan G-F 20 was consistently superior to low MW sodium hyaluronate preparations (Hyalgan, Supartz) up to 20 weeks, whereas one study reported that Durolane was noninferior to Supartz. Head-to-head trials comparing high versus medium MW preparations all used Hylan G-F 20 as the high MW preparation. Of the IAHA preparations with strong evidence of efficacy in placebo-controlled studies, Euflexxa was found to be noninferior to Hylan G-F 20. There are no direct comparisons to Monovisc. One additional IAHA preparation (ie, Synovial), which has not been assessed in placebo-controlled studies, was also noninferior to Hylan G-F 20. CONCLUSION: IAHA efficacy varies widely across preparations. High-quality studies are required to assess and compare the safety and efficacy of IAHA preparations.

RNAi-mediated knockdown of PFK1 decreases the invasive capability and metastasis of nasopharyngeal carcinoma cell line, CNE-2.

Nasopharyngeal carcinoma (NPC) is the most prevailing malignancy of the head and neck with unique geographic distribution. Southern China has one of the highest incidence rates of NPC in the world. Although radiotherapy and chemotherapy are the most important treatment modalities for NPC, recurrence, and metastasis severely interfere with the survival quality of patients. It is much-needed to find an effective method of NPC treatment with a good prognosis such as gene therapy. PFK1, a key regulatory enzyme of glycolysis, is frequently shown to be amplified and overexpressed in a variety of human cancers. However, the function of PFK1 and molecular mechanism in NPC is elusive. Here, we knockdown PFK1 expression by utilizing DNA vector-based RNA Interference. Western blotting and real-time PCR show that the expression of PFK1 is efficiently down-regulated in both protein and mRNA levels by stable transfection with PFK1 siRNA expression vector. In addition, stable knockdown of PFK1 expression inhibits cell growth, induces apoptosis, decreases the invasive capability and metastasis in the CNE2 human NPC cell line. This present study finds the importance of PFK1 which can be worked as a novel target in NPC treatment and holds great potential to be extended to other malignant cancers.

Oxygen availability affects the synthesis of quorum sensing signal in the facultative anaerobe Novosphingobium pentaromativorans US6-1.

Bacterial populations rely on quorum sensing (QS) to coordinate their behaviors and are often challenged by the fluctuation in oxygen concentrations in their habitats. Oxygen is a crucial factor that affects bacterial metabolism in multiple ways. However, little is known about whether and how oxygen availability affects QS activities. To fill this gap, we used the facultative anaerobe Novosphingobium pentaromativorans US6-1 as a model system, and observed that the QS signal acyl homoserine-lactones (AHLs) were produced only in anoxic environments, such as biofilm, or liquid medium that initially contained less than 2 mg/L dissolved oxygen, but not in highly oxic environments. Comparative transcriptome analysis revealed that oxygen availability significantly affected the physiological activities in US6-1, including fatty acid metabolism, oxidative phosphorylation, citrate cycle, QS activities, and flagellar assembly. The absence of AHLs in the oxic culture was not due to degradation, but to the very low expression of the AHL synthase gene novI. High concentration of NADH during the middle log phase under static cultivation may be a trigger for AHL synthesis. This is the first report that production of AHLs is coupled with anoxic metabolism in a facultative anaerobe, which extends our knowledge on factors affecting bacterial QS occurrence. KEY POINTS: • AHL production is anoxic cultivation related. • Oxygen availability affects AHL synthesis by influencing novI expression. • Oxygen availability changes many metabolism activities including NADH production.

Approach to Tibiopedal Retrograde Revascularization of Below-The-Knee Peripheral Arterial Diseases With or Without Transradial Guidance Peripheral Angiography.

OBJECTIVE: We sought to compare the use of transradial peripheral angiography to guide retrograde revascularization of below-the-knee (BTK) lesions using tibiopedal access (TPA). BACKGROUND: Tibiopedal retrograde revascularization of BTK lesions is an emerging technique in peripheral interventions. METHODS: We performed an observational cohort study of 194 consecutive adult patients with critical limb ischemia (CLI) who underwent endovascular intervention for BTK diseases using peripheral angiography and primary TPA access with vs without transradial (TR) guidance at 2 centers (New York, USA and Budapest, Hungary). The primary endpoints were procedure success, 30-day major adverse event rate, 30-day access-site complication rate, and 30-day access-site patency rate by ultrasound. Secondary endpoints were periprocedural complications, fluoroscopy time, procedure length, and crossover rate to femoral access. RESULTS: There were 78 patients in the TR-guidance group and 116 patients in the non-TR guidance group. Overall procedure success rates with TR guidance vs without TR guidance were 97% and 98%, respectively. Fluoroscopy times (732.8 ± 615.7 seconds vs 769.8 ± 565.8 seconds; P=NS) and procedure times (46.5 ± 24.4 minutes vs 55.4 ± 12.6 minutes; P=NS) were similar in the TR-guidance group vs the non-TR guidance group, but contrast volumes were higher in the TR-guidance group (100.0 ± 60.1 mL vs 43.8 ± 10.2 mL in the non-TR guidance group; P<.05). There was no difference in 30-day major adverse events, other than higher amputation rate in the TR-guidance group (15.3%), which was attributed to severe baseline complex CLI status in this patient group. There was 1 case of arteriovenous fistula, 1 case of pseudoaneurysm, and 1 case of tibiopedal artery occlusion at 30 days in the group without TR guidance. There were 3 cases (3.8%) of radial artery occlusion in the TR-guidance group. CONCLUSIONS: The treatment of CLI with BTK lesions is feasible and safe, with a high procedural success rate and low access-site complication rate using the TPA approach regardless of whether or not TR guidance is utilized.

Structure and product relationship analysis of acyl homoserine lactone synthases among Ensifer adhaerens reveals distinct chromosome and plasmid origins.

Despite the conservative DNA sequences among LuxI (Acyl Homoserine Lactones synthase gene) homologs, structure-product relationship of AHL synthase remains to be elucidated. In this study, through degenerate primers and in vitro expression methods, we collected the information of the gene sequences and AHL profiles from nine LuxIs among Ensifer adhaerens strains. The chromosome-encoded LuxI (C-LuxI) distinguished themselves from the plasmid-encoded ones (P-LuxI) not only in the DNA sequences, but also in AHL profiles. The C-LuxIs produced only C14-HSL, while the P-LuxIs produced predominantly C8-HSL and 3-oxo-C8-HSL. Sequence-product relationship analysis updated our recognition of the role of T140 (EsaI) in the 3-oxo-HSL production. Computational calculation based on 3D structures of these LuxIs revealed the linear relationship between the chain length and the affinity of amides to AHL synthase in C-LuxI, which was not found in the P-LuxI. We hereby proposed the linear docking affinity as a criterion for the prediction of long-chain AHL production by an AHL synthase. This study extends our understanding on the structure-product relationship of AHL synthases and revealed the distinct chromosome and plasmid origin of this enzyme among E. adhaerens.

Functional hemodynamics assessment during endovascular Tibio-pedal retrograde intervention of peripheral arterial disease.

OBJECTIVE: We sought to use a novel technique to measure the functional hemodynamics of peripheral arterial lesions during endovascular interventions. BACKGROUND: Functional hemodynamics has not been thoroughly evaluated during endovascular interventions. The aim of our study is to evaluate the feasibility and the potential benefits of pedal pressures measurements from tibio-pedal access. METHODS: We retrospectively reviewed 100 consecutive patients who underwent endovascular interventions via tibio-pedal artery access between October 3, 2018 and December 15, 2018. Baseline and postintervention pedal pressures from the pedal sheaths were measured. We also evaluated the pedal-brachial index (PBI) which is defined as the pedal sheath pressure divided by the simultaneously brachial cuff pressure. We compared baseline pedal pressures, postintervention pedal pressures, baseline PBI, postintervention PBI, % change of PBI ([postintervention PBI minus baseline PBI]/baseline PBI), and resting ankle-brachial index (ABI) versus baseline PBI in this cohort of patients. RESULTS: All 100 patients had successful tibio-pedal artery access. Baseline pedal pressure was 70 + 30 mmHg with post intervention pedal pressure of 133 + 27 mmHg (p < .001). Baseline PBI was 0.75 + 0.24 with post intervention PBI of 1.09 + 0.19 (p < .001). The correlation coefficient of resting ABI vs. baseline PBI was 0.55. The % change of PBI was 63.2 + 52.4%. There was significant improvement of postintervention PBI when compared to baseline PBI in the majority of patients. CONCLUSIONS: Obtaining pedal pressures and PBI from tibio-pedal access can be a feasible tool for endovascular interventions. This simple technique can provide us important functional hemodynamics information before and after peripheral revascularization.

Double bonds of unsaturated fatty acids differentially regulate mitochondrial cardiolipin remodeling.

BACKGROUND: Supplemented fatty acids can incorporate into cardiolipin (CL) and affect its remodeling. The change in CL species may alter the mitochondrial membrane composition, potentially disturbing the mitochondrial structure and function during inflammation. METHOD: To investigate the effect of the unsaturation of fatty acids on CL, we supplemented macrophage-like RAW264.7 cells with 18-carbon unsaturated fatty acids including oleic acid (OA, 18:1), linoleic acid (LA, 18:2), α-linolenic acid (ALA, 18:3), γ-linolenic acid (GLA, 18:3), and stearidonic acid (SDA, 18:4). Mitochondrial changes in CL were measured through mass spectrometry. RESULT: Our data indicated that OA(18:1) was the most efficient fatty acid that incorporated into CL, forming symmetrical CL without fatty acid elongation and desaturation. In addition, LA(18:2) and ALA(18:3) were further elongated before incorporation, significantly increasing the number of double bonds and the chain length of CL. GLA and SDA were not optimal substrates for remodeling enzymes. The findings of RT-qPCR experiments revealed that none of these changes in CL occurred through the regulation of CL remodeling- or synthesis-related genes. The fatty acid desaturase and transportation genes-Fads2 and Cpt1a, respectively-were differentially regulated by the supplementation of five unsaturated 18-carbon fatty acids. CONCLUSIONS: The process of fatty acid incorporation to CL was regulated by the fatty acid desaturation and transportation into mitochondria in macrophage. The double bonds of fatty acids significantly affect the incorporation process and preference. Intact OA(18:1) was incorporated to CL; LA(18:2) and ALA(18:3) were desaturated and elongated to long chain fatty acid before the incorporation; GLA(18:3) and SDA(18:4) were unfavorable for the CL incorporation.