Activation and Signaling Mechanism Revealed by Cannabinoid Receptor-Gi Complex Structures.

Human endocannabinoid systems modulate multiple physiological processes mainly through the activation of cannabinoid receptors CB1 and CB2. Their high sequence similarity, low agonist selectivity, and lack of activation and G protein-coupling knowledge have hindered the development of therapeutic applications. Importantly, missing structural information has significantly held back the development of promising CB2-selective agonist drugs for treating inflammatory and neuropathic pain without the psychoactivity of CB1. Here, we report the cryoelectron microscopy structures of synthetic cannabinoid-bound CB2 and CB1 in complex with Gi, as well as agonist-bound CB2 crystal structure. Of important scientific and therapeutic benefit, our results reveal a diverse activation and signaling mechanism, the structural basis of CB2-selective agonists design, and the unexpected interaction of cholesterol with CB1, suggestive of its endogenous allosteric modulating role.

Crystal Structure of the Human Cannabinoid Receptor CB2.

The cannabinoid receptor CB2 is predominately expressed in the immune system, and selective modulation of CB2 without the psychoactivity of CB1 has therapeutic potential in inflammatory, fibrotic, and neurodegenerative diseases. Here, we report the crystal structure of human CB2 in complex with a rationally designed antagonist, AM10257, at 2.8 Å resolution. The CB2-AM10257 structure reveals a distinctly different binding pose compared with CB1. However, the extracellular portion of the antagonist-bound CB2 shares a high degree of conformational similarity with the agonist-bound CB1, which led to the discovery of AM10257's unexpected opposing functional profile of CB2 antagonism versus CB1 agonism. Further structural analysis using mutagenesis studies and molecular docking revealed the molecular basis of their function and selectivity for CB2 and CB1. Additional analyses of our designed antagonist and agonist pairs provide important insight into the activation mechanism of CB2. The present findings should facilitate rational drug design toward precise modulation of the endocannabinoid system.

Arc-Induced Electrospray Ionization Mass Spectrometry.

Arc-induced electrospray ionization mass spectrometry (AESI-MS) was developed during which alternating current electrospray is simply achieved through the arc plasma. The AESI source exploits the arc's temperature and charge properties to generate aerosols consisting of charged microdroplets. The electrospray region, in which organic molecules are contained within microdroplets, partially overlaps with the arc plasma region. Guided by the electric field, these molecules undergo ionization, yielding ionic target analytes. AESI represents a soft ionization method that combines the mechanisms of atmospheric pressure chemical ionization and electrospray ionization, facilitating the ionization of analytes with wide ranging polarities. The precisely targeted spraying area enhances ion entry into the mass analyzer, thereby enabling excellent ionization efficiency. The AESI source exhibits several notable advantages over the electrospray ionization source, including an elevated but comparable level of active species concentrations and types, simplified mass spectra for direct amino acid analysis, high salt tolerance, versatile analysis of compounds with varying polarities, and reliable quantitative analysis of amino acids in complex matrices. Overall, AESI broadens the methodologies employed to generate microdroplets, providing a technological and scientific framework for creating distinctive electrospray ionization techniques.

CD74 is associated with inflamed tumor immune microenvironment and predicts responsiveness to PD-1/CTLA-4 bispecific antibody in patients with solid tumors.

INTRODUCTION: Cadonilimab (AK104) is a first-in-class tetravalent bispecific antibody that targets both PD-1 and CTLA-4, showing a manageable safety profile and favorable clinical benefits. This study aimed to identify the biomarkers of clinical response and explore the immune response within the tumor microenvironment upon the AK104 therapy in advanced solid tumors. MATERIAL AND METHODS: Gene expression profiles of paired pre- and post-treatment tumor tissues from twenty-one patients were analyzed. The association of gene expression levels with either clinical efficacy or prognosis was evaluated and subsequently validated with published datasets using log-rank for Kaplan-Meier estimates. Comparative immune profile analyses of tumor microenvironment before and after AK104 treatment were conducted. The visualization of tumor-infiltrating lymphocytes was performed using multiplex immunohistochemistry. The predictive value of CD74 was further validated with protein expression by immunohistochemistry. RESULTS: Baseline CD74 gene expression was associated with favorable patient outcomes (overall survival [OS], HR = 0.33, 95% CI 0.11-1.03, p = 0.0463), which was further confirmed with the published datasets. Tumors with high CD74 gene expression at baseline were more likely to exhibit an immune-inflamed microenvironment. AK104 efficiently enhanced the infiltration of immune cells in the tumor microenvironment. Additionally, high CD74 protein expression (≥ 10% of the tumor area occupied by CD74 stained immune cells) at baseline was associated with better progressive-free survival (HR = 0.21, 95% CI 0.06-0.68, p = 0.0065) and OS (HR = 0.35, 95% CI 0.12-1.08, p = 0.0615). CONCLUSIONS: Our findings demonstrate that CD74 is a promising predictive biomarker for AK104 therapeutic response in advanced solid tumors. Trial registration number NCT03261011.

Extranodal Extension at Pretreatment MRI and the Prognostic Value for Patients with Rectal Cancer.

Background Detection of extranodal extension (ENE) at pathology is a poor prognostic indicator for rectal cancer, but whether ENE can be identified at pretreatment MRI is, to the knowledge of the authors, unknown. Purpose To evaluate the performance of pretreatment MRI in detecting ENE using a matched pathologic reference standard and to assess its prognostic value in patients with rectal cancer. Materials and Methods This single-center study included a prospective development data set consisting of participants with rectal adenocarcinoma who underwent pretreatment MRI and radical surgery (December 2021 to January 2023). MRI characteristics were identified by their association with ENE-positive nodes (χ2 test and multivariable logistic regression) and the performance of these MRI features was assessed (area under the receiver operating characteristic curve [AUC]). Interobserver agreement was assessed by Cohen κ coefficient. The prognostic value of ENE detected with MRI for predicting 3-year disease-free survival was assessed by Cox regression analysis in a retrospective independent validation cohort of patients with locally advanced rectal cancer (December 2019 to July 2020). Results The development data set included 147 participants (mean age, 62 years ± 11 [SD]; 87 male participants). The retrospective cohort included 110 patients (mean age, 60 years ± 9; 79 male participants). Presence of vessel interruption and fusion (both P < .001), heterogeneous internal structure, and the broken-ring and tail signs (odds ratio range, 4.10-23.20; P value range, <.001 to .002) were predictors of ENE at MRI, and together achieved an AUC of 0.91 (95% CI: 0.88, 0.93) in detecting ENE. Interobserver agreement was moderate for the presence of vessel interruption and fusion (κ = 0.46 for both) and substantial for others (κ = 0.61-0.67). The presence of ENE at pretreatment MRI was independently associated with worse 3-year disease-free survival (hazard ratio, 3.00; P = .02). Conclusion ENE can be detected at pretreatment MRI, and its presence was associated with worse prognosis for patients with rectal cancer. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Eberhardt in this issue.

Early Contrast-Enhanced MR for Diagnosing Complete Tumor Response of Locally Advanced Esophageal Squamous Cell Carcinoma After Neoadjuvant Therapy: A Retrospective Comparative Study.

BACKGROUND: This study assessed the performance of early contrast-enhanced magnetic resonance (ECE-MR) in the detecting of complete tumor response (ypT0) in patients with esophageal squamous cell carcinoma following neoadjuvant therapy. PATIENTS AND METHODS: Preoperative MR images of consecutive patients who underwent neoadjuvant therapy and surgical resection were reviewed retrospectively. The accuracy of ECE-MR and T2WI+DWI was evaluated by comparing the findings with pathological results. Receiver operating characteristic curve analysis was used to assess the diagnostic performance, and DeLong method was applied to compare the areas under the curves (AUC). Chi-squared analysis was conducted to explore the difference in pathological changes. RESULTS: A total of 198 patients (mean age 62.6 ± 7.8 years, 166 men) with 201 lesions were included. The AUC of ECE-MR was 0.85 (95% CI 0.79-0.90) for diagnosing ypT1-4, which was significantly higher than that of T2WI+DWI (AUC 0.69, 95% CI 0.63-0.76, p < 0.001). The diagnostic performance of both T2WI+DWI and ECE-MR improved with increasing tumor stage. The AUCs of ECE-MRI were higher in ypT1 and ypT2 tumors than T2WI+DWI. Degree 2-3 tumor-infiltrating lymphocytes and neutrophils were commonly seen in ypT0 tumors misdiagnosed by ECE-MR. CONCLUSIONS: Visual evaluation of ECE-MR is a promising diagnostic protocol for the detection of complete tumor response, especially for differentiation with early stage tumors. The accurate diagnosis of complete tumor response after neoadjuvant therapy using imaging modalities is of important significance for clinical decision-making for patients with esophageal squamous cell carcinoma. It is hoped that early contrast-enhanced MR will provide supportive advice for the development of individualized treatment options for patients.

Fully semantic segmentation for rectal cancer based on post-nCRT MRl modality and deep learning framework.

PURPOSE: Rectal tumor segmentation on post neoadjuvant chemoradiotherapy (nCRT) magnetic resonance imaging (MRI) has great significance for tumor measurement, radiomics analysis, treatment planning, and operative strategy. In this study, we developed and evaluated segmentation potential exclusively on post-chemoradiation T2-weighted MRI using convolutional neural networks, with the aim of reducing the detection workload for radiologists and clinicians. METHODS: A total of 372 consecutive patients with LARC were retrospectively enrolled from October 2015 to December 2017. The standard-of-care neoadjuvant process included 22-fraction intensity-modulated radiation therapy and oral capecitabine. Further, 243 patients (3061 slices) were grouped into training and validation datasets with a random 80:20 split, and 41 patients (408 slices) were used as the test dataset. A symmetric eight-layer deep network was developed using the nnU-Net Framework, which outputs the segmentation result with the same size. The trained deep learning (DL) network was examined using fivefold cross-validation and tumor lesions with different TRGs. RESULTS: At the stage of testing, the Dice similarity coefficient (DSC), 95% Hausdorff distance (HD95), and mean surface distance (MSD) were applied to quantitatively evaluate the performance of generalization. Considering the test dataset (41 patients, 408 slices), the average DSC, HD95, and MSD were 0.700 (95% CI: 0.680-0.720), 17.73 mm (95% CI: 16.08-19.39), and 3.11 mm (95% CI: 2.67-3.56), respectively. Eighty-two percent of the MSD values were less than 5 mm, and fifty-five percent were less than 2 mm (median 1.62 mm, minimum 0.07 mm). CONCLUSIONS: The experimental results indicated that the constructed pipeline could achieve relatively high accuracy. Future work will focus on assessing the performances with multicentre external validation.

ICP-MS based detection method combined with Au NP and Ag NP labeling for bacteremia diagnosis.

Bacteremia, as a serious infectious disease, has an increasing incidence and a high mortality rate. Early diagnosis and early treatment are crucial for improving the cure rate. In this work, we proposed an inductively coupled plasma mass spectrometry (ICP-MS)-based detection method combined with gold nanoparticle (Au NP) and silver nanoparticle (Ag NP) labeling for the simultaneous detection of Salmonella and Escherichia coli (E. coli O157:H7) in human blood samples. Salmonella and E. coli O157:H7 were captured by magnetic beads coupled with anti-8G3 and anti-7C2, and then specifically labeled by Au NP-anti-5H12 and Ag NP-anti-8B1 respectively, which were used as signal probes for ICP-MS detection. Under the optimal experimental conditions, the limits of detection of 164 CFU mL-1 for Salmonella, 220 CFU mL-1for E. coli O157:H7 and the linear ranges of 400-80,000 CFU mL-1Salmonella, 400-60,000 CFU mL-1 E. coli O157:H7 were obtained. The proposed method can realize the simultaneous detection of two types of pathogenic bacteria in human whole blood in 3.5 h, showing great potential for the rapid diagnosis of bacteremia in clinic.

Radiomics analysis from magnetic resonance imaging in predicting the grade of nonfunctioning pancreatic neuroendocrine tumors: a multicenter study.

OBJECTIVES: To explore the potential of radiomics features to predict the histologic grade of nonfunctioning pancreatic neuroendocrine tumor (NF-PNET) patients using non-contrast sequence based on MRI. METHODS: Two hundred twenty-eight patients with NF-PNETs undergoing MRI at 5 centers were retrospectively analyzed. Data from center 1 (n = 115) constituted the training cohort, and data from centers 2-5 (n = 113) constituted the testing cohort. Radiomics features were extracted from T2-weighted images and the apparent diffusion coefficient. The least absolute shrinkage and selection operator was applied to select the most important features and to develop radiomics signatures. The area under receiver operating characteristic curve (AUC) was performed to assess models. RESULTS: Tumor boundary, enhancement homogeneity, and vascular invasion were used to construct the radiological model to stratify NF-PNET patients into grade 1 and 2/3 groups, which yielded AUC of 0.884 and 0.684 in the training and testing groups. A radiomics model including 4 features was constructed, with an AUC of 0.941 and 0.871 in the training and testing cohorts. The fusion model combining the radiomics signature and radiological characteristics showed good performance in the training set (AUC = 0.956) and in the testing set (AUC = 0.864), respectively. CONCLUSION: The developed model that integrates radiomics features with radiological characteristics could be used as a non-invasive, dependable, and accurate tool for the preoperative prediction of grade in NF-PNETs. CLINICAL RELEVANCE STATEMENT: Our study revealed that the fusion model based on a non-contrast MR sequence can be used to predict the histologic grade before operation. The radiomics model may be a new and effective biological marker in NF-PNETs. KEY POINTS: The diagnostic performance of the radiomics model and fusion model was better than that of the model based on clinical information and radiological features in predicting grade 1 and 2/3 of nonfunctioning pancreatic neuroendocrine tumors (NF-PNETs). Good performance of the model in the four external testing cohorts indicated that the radiomics model and fusion model for predicting the grades of NF-PNETs were robust and reliable, indicating the two models could be used in the clinical setting and facilitate the surgeons' decision on risk stratification. The radiomics features were selected from non-contrast T2-weighted images (T2WI) and diffusion-weighted imaging (DWI) sequence, which means that the administration of contrast agent was not needed in grading the NF-PNETs.

Family-based Helicobacter pylori infection control and management strategy and screen-and-treat strategy are highly cost-effective in preventing multiple upper gastrointestinal diseases in Chinese population at national level.

BACKGROUND: The overall benefits of the newly introduced family-based Helicobacter pylori (H. pylori) infection control and management (FBCM) and screen-and-treat strategies in preventing multiple upper gastrointestinal diseases at national level in China have not been explored. We investigate the cost-effectiveness of these strategies in the whole Chinese population. MATERIALS AND METHODS: Decision trees and Markov models of H. pylori infection-related non-ulcer dyspepsia (NUD), peptic ulcer disease (PUD), and gastric cancer (GC) were developed to simulate the cost-effectiveness of these strategies in the whole 494 million households in China. The main outcomes include cost-effectiveness, life years (LY), quality-adjusted life year (QALY), and incremental cost-effectiveness ratio (ICER). RESULTS: When compared with no-screen strategy, both FBCM and screen-and-treat strategies reduced the number of new cases of NUD, PUD, PUD-related deaths, and the prevalence of GC, and cancer-related deaths. The costs saved by these two strategies were $1467 million and $879 million, quality-adjusted life years gained were 227 million and 267 million, and life years gained were 59 million and 69 million, respectively. Cost-effectiveness analysis showed that FBCM strategy costs -$6.46/QALY and -$24.75/LY, and screen-and-treat strategy costs -$3.3/QALY and -$12.71/LY when compared with no-screen strategy. Compared to the FBCM strategy, the screen-and-treat strategy reduced the incidence of H. pylori-related diseases, added 40 million QALYs, and saved 10 million LYs, but at the increased cost of $588 million. Cost-effectiveness analysis showed that screen-and-treat strategy costs $14.88/QALY and $59.5/LY when compared with FBCM strategy. The robustness of the results was also verified. CONCLUSIONS: Both FBCM and screen-and-treat strategies are highly cost-effective in preventing NUD, PUD, and GC than the no-screen strategy in Chinese families at national level. As FBCM strategy is more practical and efficient, it is expected to play a more important role in preventing familial H. pylori infection and also serves as an excellent reference for other highly infected societies.

Improved Patient Adherence to Family-Based Helicobacter pylori Infection Control and Management Strategy in Central China and Its Influencing Factors.

BACKGROUND: Patient adherence status to the newly introduced family-based Helicobacter pylori (H. pylori) infection control and management strategy remains unclear, so are its influencing factors. We aim to investigate family members' adherence and its influencing factors during the family-based H. pylori infection management practice for related disease prevention. MATERIALS AND METHODS: Based on our previously family-based H. pylori survey in 2021, 282 families including 772 individuals were followed up 2 years after the initial survey to compare if the investigation and education might improve family member's adherence. The participant's adherence to H. pylori infection awareness, retest, treatment, publicity, gastroscopy, and hygiene habits were followed up, and their influencing factors were also analyzed. RESULTS: The overall participant's adherence to recommendations on H. pylori awareness, retest, treatment, publicity, gastroscopy, and hygiene habits were 77% (187/243), 67.3% (138/205), 60.1% (211/351), 46.5% (107/230), 45.6% (159/349), and 39.1% (213/545), respectively; and all showed improvements compared with their prior survey stages. The top reasons for rejection to treatment, retest, and gastroscopy were forgetting or unaware of H. pylori infection (30.3%), busy (32.8%), and asymptomatic (67.9%), respectively. Independent risk factor for low adherence to treatment was occupation (e.g., staff: OR 4.49, 95% CI 1.34-15.10). Independent favorable factors for treatment adherence were individuals at the ages of 18-44 years (OR 0.19, 95% CI 0.04-0.89) and had a large family size (e.g., four family members: OR 0.15, 95% CI 0.06-0.41); for retest adherence, it was individuals at the ages of 60-69 years (OR 0.23, 95% CI 0.06-0.97); for gastroscopy adherence, it was individuals at the age of 60-69 years (OR 0.46, 95% CI 0.28-0.75), and with gastrointestinal symptoms (OR 0.57, 95% CI 0.36-0.90). CONCLUSIONS: Family-based H. pylori management increases individual adherence to treatment, retest, and awareness, and there are also improved adherence to gastroscopy, publicity, and personal hygiene recommendations; further efforts are required to enhance the individual adherence rate for related disease prevention.

Nupr1-mediated vascular smooth muscle cell phenotype transformation involved in methamphetamine induces pulmonary hypertension.

AIMS: Nuclear protein 1 (Nupr1) is a multifunctional stress-induced protein involved in the regulation of tumorigenesis, apoptosis, and autophagy. However, its role in pulmonary hypertension (PH) after METH exposure remains unexplored. In this study, we aimed to investigate whether METH can induce PH and describe the role and mechanism of Nupr1 in the development of PH. METHODS AND RESULTS: Mice were made to induce pulmonary hypertension (PH) upon chronic intermittent treatment with METH. Their right ventricular systolic pressure (RVSP) was measured to assess pulmonary artery pressure. Pulmonary artery morphometry was determined by H&E staining and Masson staining. Nupr1 expression and function were detected in human lungs, mice lungs exposed to METH, and cultured pulmonary arterial smooth muscle cells (PASMCs) with METH treatment. Our results showed that chronic intermittent METH treatment successfully induced PH in mice. Nupr1 expression was increased in the cultured PASMCs, pulmonary arterial media from METH-exposed mice, and METH-ingested human specimens compared with control. Elevated Nupr1 expression promoted PASMC phenotype change from contractile to synthetic, which triggered pulmonary artery remodeling and resulted in PH formation. Mechanistically, Nupr1 mediated the opening of store-operated calcium entry (SOCE) by activating the expression of STIM1, thereby promoting Ca2+ influx and inducing phenotypic conversion of PASMCs. CONCLUSIONS: Nupr1 activation could promote Ca2+ influx through STIM1-mediated SOCE opening, which promoted METH-induced pulmonary artery remodeling and led to PH formation. These results suggested that Nupr1 played an important role in METH-induced PH and might be a potential target for METH-related PH therapy.

Panaxadiol carbamate derivatives: Synthesis and biological evaluation as potential multifunctional anti-Alzheimer agents.

It is reported that panaxadiol has neuroprotective effects. Previous studies have found that compound with carbamate structure introduced at the 3-OH position of 20 (R) -panaxadiol showed the most effective neuroprotective activity with an EC50 of 13.17 µM. Therefore, we designed and synthesized a series of ginseng diol carbamate derivatives with ginseng diol as the lead compound, and tested their anti-AD activity. It was found that the protective effect of compound Q4 on adrenal pheochromocytoma was 80.6 ±â€¯10.85 % (15 µM), and the EC50 was 4.32 µM. According to the ELISA results, Q4 reduced the expression of Aß25-35 by decreasing ß-secretase production. Molecular docking studies revealed that the binding affinity of Q4 to ß-secretase was -49.67 kcal/mol, indicating a strong binding affinity of Q4 to ß-secretase. Western blotting showed that compound Q4 decreased IL-1ß levels, which may contribute to its anti-inflammatory effect. Furthermore, compound Q4 exhibits anti-AD activities by reducing abnormal phosphorylation of tau protein and activation of the mitogen activated protein kinase pathway. The learning and memory deficits in mice treated with Q4in vivo were significantly alleviated. Therefore, Q4 may be a promising multifunctional drug for the treatment of AD, providing a new way for anti-AD drugs.

Interaction between antiretroviral therapy regimens and body mass index on triglyceride levels in people living with HIV: a cross-sectional and longitudinal study.

OBJECTIVE: To investigate how antiretroviral therapy (ART) regimens and body mass index (BMI) interact to affect triglyceride (TG) levels in people living with HIV (PLWH). METHODS: This research involved 451 men living with HIV for cross-sectional analysis, and 132 underwent follow-up assessments in 2021 and 2023. Multivariate logistic regression identified key factors, while covariance regression models assessed interactions between ART regimens and BMI on TG levels. RESULTS: The result of this cross-sectional study indicated that advanced AIDS (acquired immune deficiency syndrome) stage (OR = 2.756, P = 0.003), higher BMI (OR = 1.131, P = 0.003), and waist-hip ratio (WHR, OR = 44.684, P = 0.019) are closely associated with high triglyceride levels. Additionally, regimens containing zidovudine (AZT) (OR = 3.927, P < 0.001) or protease inhibitors/integrase strand transfer inhibitors (PI/INSTI) (OR = 5.167, P < 0.001) were significantly linked to hypertriglyceridemia. Cross-sectional and longitudinal analyses from 2021 to 2023 emphasized that changes in BMI interact with antiretroviral treatment regimens to affect TG levels in PLWH (Pinteraction < 0.05). Especially in the AZT-based drug regimen, the correlation between BMI and TG is more prominent. CONCLUSION: The interaction between ART regimens and BMI influences TG levels in PLWH, indicating that weight management is crucial for reducing the risk of hypertriglyceridemia in this population.

Enhancement of poly­Î³­L­diaminobutanoic acid production in Bacillus pumilus by repeated pH shocks.

This study investigated the effect of pH on poly-γ-L-diaminobutanoic acid (γ-PAB) production by Bacillus pumilus in batch fermentation. In the natural fermentation where pH was not controlled, pH decreased from initial 7.0 to 3.0 in 18 h and γ-PAB production was 428.6 mg/L. In the pH-controlled fermentation, B. pumilus tended to proliferation at higher pH, while γ-PAB synthesis was favorable at lower pH, in which the optimal pH for γ-PAB production was 4.2, and γ-PAB yield reached 2284.5 mg/L. Adopting a pH shock strategy which lasted 9 h in the pre-fermentation phase, biomass (OD600) and γ-PAB yield of B. pumilus were obtained as 61.3 and 2794.6 mg/L, respectively, which were 10.8% and 22.4% higher than those in batch fermentation without pH shock. Subsequent fermentation of repeated pH shocks showed that a further higher productivity could be achieved, in which the final OD600 reached 65.1, and γ-PAB production reached as high as 3482.3 mg/L, which were increased by 6.2% and 17.1% compared with those in single pH shock, respectively. This study demonstrated that B. pumilus can synthesize more γ-PAB at suboptimal pH and provided a novel approach to regulate γ-PAB synthesis.

Enhanced ε­poly­L­lysine production in Streptomyces species by combining interspecific hybridization with multiple antibiotic resistance.

To improve the ε-PL production in wild-type strains of Streptomyces. albulus, Streptomyces. noursei, Streptomyces. rochei and Streptomyces. yunnanensis, the interspecific hybridization based on protoplast fusion was first performed. Two-species hybridizations failed to obtain hybrids with significant increase in ε-PL production, but four-species hybridizations succeed in acquiring many high-yield hybrids. 16S rDNA homology alignment and RAPD confirmed that the hybrid HX17 was restructured by integrating gene fragments from S. albulus and S. rochei with S. noursei as the carrier. S. noursei HX17 was subsequently suffered from mutagenesis and genome shuffling combining with multiple antibiotic resistance, and a mutant S. noursei GX6 was obtained with ε-PL yield of 2.23 g/L in shake-flask fermentation. In fed-batch fermentation, the ε-PL production of GX6 reached 47.2 g/L, which was increased by 95.6% to 136.8% over the wild parents. Ribosomal genes associated with antibiotics were sequenced and majority of mutant strains had mutations at different sites, indicating that the increase of antibiotic resistance was strongly associated with them. This research proved that combining interspecific hybridization with multiple antibiotic resistance was as an effective approach to rapidly improve the ε-PL production in Streptomyces species.

Likelihood Inference for Factor Copula Models with Asymmetric Tail Dependence.

For multivariate non-Gaussian involving copulas, likelihood inference is dominated by the data in the middle, and fitted models might not be very good for joint tail inference, such as assessing the strength of tail dependence. When preliminary data and likelihood analysis suggest asymmetric tail dependence, a method is proposed to improve extreme value inferences based on the joint lower and upper tails. A prior that uses previous information on tail dependence can be used in combination with the likelihood. With the combination of the prior and the likelihood (which in practice has some degree of misspecification) to obtain a tilted log-likelihood, inferences with suitably transformed parameters can be based on Bayesian computing methods or with numerical optimization of the tilted log-likelihood to obtain the posterior mode and Hessian at this mode.

Analysis of the survival journey and post-traumatic growth process of children and their families following paediatric intensive care unit admission: A grounded theory study.

OBJECTIVES: Advances in critical care technology have lowered mortality rates among critically ill individuals. Nonetheless, survivors and their families may develop new physical, mental, cognitive, and social challenges due to paediatric intensive care unit (PICU) treatments, impacting their quality of life. The aim of this study was to investigate the survival journey and post-traumatic growth process of children and their families following PICU admission within the Chinese cultural context. METHODS: Twenty-six children who have been or are currently admitted to the PICU, alongside their parents and three PICU nurses, were chosen through purposive and theoretical sampling. Data collection involved face-to-face interviews and observations, with data analysis conducted through continuous comparison, open coding, and selective coding techniques. FINDINGS: A model outlining the survival journey and post-traumatic growth process of critically ill children and their families post PICU admission has been established. This model encompasses two central trajectories: an upward trajectory consisting of confusion, charging, action, and sublimation phases and a downward trajectory comprising confusion, doubt and fear, inhibition (including confrontation and avoidance), and drowning phases. CONCLUSIONS: Critically ill children and their families encounter diverse survival experiences and psychological journeys following traumatic events in the PICU. The survival experience has alternative upwards or downwards trajectories that are flexible/adaptable. Hence, offering timely psychological support can alter their developmental trajectories and foster post-traumatic growth.

Lineage-specific amplification and epigenetic regulation of LTR-retrotransposons contribute to the structure, evolution, and function of Fabaceae species.

BACKGROUND: Long terminal repeat (LTR)-retrotransposons (LTR-RTs) are ubiquitous and make up the majority of nearly all sequenced plant genomes, whereas their pivotal roles in genome evolution, gene expression regulation as well as their epigenetic regulation are still not well understood, especially in a large number of closely related species. RESULTS: Here, we analyzed the abundance and dynamic evolution of LTR-RTs in 54 species from an economically and agronomically important family, Fabaceae, and also selected two representative species for further analysis in expression of associated genes, transcriptional activity and DNA methylation patterns of LTR-RTs. Annotation results revealed highly varied proportions of LTR-RTs in these genomes (5.1%~68.4%) and their correlation with genome size was highly positive, and they were significantly contributed to the variance in genome size through species-specific unique amplifications. Almost all of the intact LTR-RTs were inserted into the genomes 4 Mya (million years ago), and more than 50% of them were inserted in the last 0.5 million years, suggesting that recent amplifications of LTR-RTs were an important force driving genome evolution. In addition, expression levels of genes with intronic, promoter, and downstream LTR-RT insertions of Glycine max and Vigna radiata, two agronomically important crops in Fabaceae, showed that the LTR-RTs located in promoter or downstream regions suppressed associated gene expression. However, the LTR-RTs within introns promoted gene expression or had no contribution to gene expression. Additionally, shorter and younger LTR-RTs maintained higher mobility and transpositional potential. Compared with the transcriptionally silent LTR-RTs, the active elements showed significantly lower DNA methylation levels in all three contexts. The distributions of transcriptionally active and silent LTR-RT methylation varied across different lineages due to the position of LTR-RTs located or potentially epigenetic regulation. CONCLUSION: Lineage-specific amplification patterns were observed and higher methylation level may repress the activity of LTR-RTs, further influence evolution in Fabaceae species. This study offers valuable clues into the evolution, function, transcriptional activity and epigenetic regulation of LTR-RTs in Fabaceae genomes.

CT Radiomics for Predicting Pathological Complete Response of Axillary Lymph Nodes in Breast Cancer After Neoadjuvant Chemotherapy: A Prospective Study.

BACKGROUND: The diagnostic effectiveness of traditional imaging techniques is insufficient to assess the response of lymph nodes (LNs) to neoadjuvant chemotherapy (NAC), especially for pathological complete response (pCR). A radiomics model based on computed tomography (CT) could be helpful. PATIENTS AND METHODS: Prospective consecutive breast cancer patients with positive axillary LNs initially were enrolled, who received NAC prior to surgery. Chest contrast-enhanced thin-slice CT scan was performed both before and after the NAC (recorded as the first and the second CT respectively), and on both of them, the target metastatic axillary LN was identified and demarcated layer by layer. Using pyradiomics-based software that was independently created, radiomics features were retrieved. A pairwise machine learning workflow based on Sklearn (https://scikit-learn.org/) and FeAture Explorer was created to increase diagnostic effectiveness. An effective pairwise auto encoder model was developed by the improvement of data normalization, dimensionality reduction, and features screening scheme as well as the comparison of the prediction effectiveness of the various classifiers. RESULTS: A total of 138 patients were enrolled, and 77 (58.7%) in the overall group achieved pCR of LN after NAC. Nine radiomics features were finally chosen for modeling. The AUCs of the training group, validation group, and test group were 0.944 (0.919-0.965), 0.962 (0.937-0.985), and 1.000 (1.000-1.000), respectively, and the corresponding accuracies were 0.891, 0.912, and 1.000. CONCLUSION: The pCR of axillary LNs in breast cancer following NAC can be precisely predicted using thin-sliced enhanced chest CT-based radiomics.