Enhancing long-term frequency stability of an actively mode-locked optoelectronic oscillator via a phase-locked loop.

A method to improve the frequency stability of microwave frequency comb (MFC) signals generated by an actively mode-locked optoelectronic oscillator (AML-OEO) is proposed and experimentally demonstrated. In the experiment, fundamental mode locking in the constructed AML-OEO is achieved, producing MFC signals with a center frequency of 2.165 GHz and a repetition rate of 396.629 kHz. By locking the MFC comb tooth to a stable reference source using a phase-locked loop (PLL), the stability of MFC's center comb tooth reaches 2.4 × 10-13@1000s and the frequency stability improves by more than two orders of magnitude on a second-level time scale compared to the free-running AML-OEO. The improved frequency stability of MFC signals makes AML-OEO suitable as high-performance microwave sources for various critical applications.

A Phenome-Wide Association Study (PheWAS) of Genetic Risk for C-Reactive Protein in Children of European Ancestry: Results From the ABCD Study.

BACKGROUND: C-reactive protein (CRP) is a moderately heritable marker of systemic inflammation that is associated with adverse physical and mental health outcomes. Identifying factors associated with genetic liability to elevated CRP in childhood may inform our understanding of variability in CRP that could be targeted to prevent and/or delay the onset of related health outcomes. METHODS: We conducted a phenome-wide association study (PheWAS) of genetic risk for elevated CRP (i.e. CRP polygenic risk score [PRS]) among children genetically similar to European ancestry reference populations (median analytic n = 5,509) from the Adolescent Brain and Cognitive Development℠ (ABCD) Study. Associations between CRP PRS and 2,377 psychosocial and neuroimaging phenotypes were estimated using independent mixed effects models. Post hoc analyses examined whether: (1) covarying for measured body mass index (BMI) or removing the shared genetic architecture between CRP and BMI altered phenotypic associations, (2) sex moderated CRP PRS associations, and (3) associations are unconfounded by assortative mating or passive gene-environment correlations (using a within-family analyses). Multiple testing was adjusted for using Bonferroni and false discovery rate (FDR) correction. RESULTS: Nine phenotypes were positively associated with CRP PRS after multiple testing correction: five weight- and eating-related phenotypes (e.g. BMI, overeating), three phenotypes related to caregiver somatic problems (e.g. caregiver somatic complaints), as well as weekday video watching (all ps = 1.2 × 10-7 - 2.5 × 10-4, all p FDR s = 0.0002 - 0.05). No neuroimaging phenotypes were associated with CRP PRS (all ps = 0.0003 - 0.998; all p FDR s = 0.08 - 0.998) after correction for multiple testing. Eating and weight-related phenotypes remained associated with CRP PRS in within-family analyses. Covarying for BMI resulted in largely consistent results, and sex did not moderate any CRP PRS associations. Removing the shared genetic variance between CRP and BMI attenuated all relationships; associations with weekday video watching, caregiver somatic problems and caregiver report that the child is overweight remained significant while associations with waist circumference, weight, and caregiver report that child overeats did not. DISCUSSION: Genetic liability to elevated CRP is associated with higher weight, eating, and weekday video watching during childhood as well as caregiver somatic problems. These associations were consistent with direct genetic effects (i.e., not solely due to confounding factors like passive gene-environment correlations) and were independent of measured BMI. The majority of associations with weight and eating phenotypes were attributable to shared genetic architecture between BMI and inflammation. The relationship between genetics and heightened inflammation in later life may be partially attributable to modifiable behaviors (e.g. weight and activity levels) that are expressed as early as childhood.

Clinical Trials for Wolfram Syndrome Neurodegeneration: Novel Design, Endpoints, and Analysis Models.

Objective: Wolfram syndrome, an ultra-rare condition, currently lacks effective treatment options. The rarity of this disease presents significant challenges in conducting clinical trials, particularly in achieving sufficient statistical power (e.g., 80%). The objective of this study is to propose a novel clinical trial design based on real-world data to reduce the sample size required for conducting clinical trials for Wolfram syndrome. Methods: We propose a novel clinical trial design with three key features aimed at reducing sample size and improve efficiency: (i) Pooling historical/external controls from a longitudinal observational study conducted by the Washington University Wolfram Research Clinic. (ii) Utilizing run-in data to estimate model parameters. (iii) Simultaneously tracking treatment effects in two endpoints using a multivariate proportional linear mixed effects model. Results: Comprehensive simulations were conducted based on real-world data obtained through the Wolfram syndrome longitudinal observational study. Our simulations demonstrate that this proposed design can substantially reduce sample size requirements. Specifically, with a bivariate endpoint and the inclusion of run-in data, a sample size of approximately 30 per group can achieve over 80% power, assuming the placebo progression rate remains consistent during both the run-in and randomized periods. In cases where the placebo progression rate varies, the sample size increases to approximately 50 per group. Conclusions: For rare diseases like Wolfram syndrome, leveraging existing resources such as historical/external controls and run-in data, along with evaluating comprehensive treatment effects using bivariate/multivariate endpoints, can significantly expedite the development of new drugs.

Beneficial effects of duck-derived lactic acid bacteria on growth performance and meat quality through modulation of gut histomorphology and intestinal microflora in Muscovy ducks.

Duck-derived lactic acid bacteria (DDL) are a crucial beneficial bacterium in the intestines, contributing significantly to the health of ducks. However, the mechanism by which these DDL improves the growth performance and meat quality of Muscovy duck is not clear. In this study, A total of 800 male Muscovy ducks, initially weighing 50.15 ± 5.37 g, were randomly allocated into 4 groups, each with 4 replicates, consisting of 50 ducks per replicate. The control group consumed deep well water, while the experimental groups were given water supplemented with 1%, 3%, and 5% DDL (1.59×108 CFU/mL). The study duration was 70 d. The results revealed that Muscovy ducks drinks with the DDL significant reduced the feed conversion ratio (FCR) (P < 0.05) and increased the sweetness and richness of duck meat, among which the 5% drinking group has the most significant difference. Further study finding, the DDL significantly increased the height of villi, the ratio of villi height/crypt depth (V/C) on jejunum and colon, and the ratio of acidic mucus, neutral mucus, and glycogen to tissue area in both the duodenum and ileum of Muscovy ducks, and significantly decreased the tunel positive cells. Moreover, DDL significantly enhanced the abundance of genus beneficial bacterium (Bacillus, lentilactobacillus, Bacterodies, Lactobacillus) on duodenum and ileum. Additionally, drink with the DDL elevated the level of IgG in blood and the immune indices of the thymus and the fabricius bursa (P<0.05). Meanwhile, the meat composition analysis demonstrated that Muscovy duck drinks with the DDL raised the level of the saturated fatty acid rate(C12:0), and polyunsaturated fatty acid (C18:2 n-6 and C20:5 n-3,), and the monounsaturated (C18:1 n-7, and C18:1 n-9). Furthermore, correlation analysis finding that the growth performance of Muscovy ducks was positively correlated with the height of villi, the ratio of villi height/crypt depth (V/C), the abundance of genus beneficial bacterium. And the meat quality of Muscovy ducks has positively correlated with genus beneficial bacterium in intestinal, glutamic acid, saturated fatty acid rate and polyunsaturated fatty acid. This finding suggest DDL is an effective strategy to improve the growth performance and meat quality of Muscovy ducks by gut histomorphology and intestinal microflora.

PIEZO1 targeting in macrophages boosts phagocytic activity and foam cell apoptosis in atherosclerosis.

The rising incidences of atherosclerosis have necessitated efforts to identify novel targets for therapeutic interventions. In the present study, we observed increased expression of the mechanosensitive calcium channel Piezo1 transcript in mouse and human atherosclerotic plaques, correlating with infiltration of PIEZO1-expressing macrophages. In vitro administration of Yoda1, a specific agonist for PIEZO1, led to increased foam cell apoptosis and enhanced phagocytosis by macrophages. Mechanistically, PIEZO1 activation resulted in intracellular F-actin rearrangement, elevated mitochondrial ROS levels and induction of mitochondrial fragmentation upon PIEZO1 activation, as well as increased expression of anti-inflammatory genes. In vivo, ApoE-/- mice treated with Yoda1 exhibited regression of atherosclerosis, enhanced stability of advanced lesions, reduced plaque size and necrotic core, increased collagen content, and reduced expression levels of inflammatory markers. Our findings propose PIEZO1 as a novel and potential therapeutic target in atherosclerosis.

RPLP1 restricts HIV-1 transcription by disrupting C/EBPß binding to the LTR.

Long-term non-progressors (LTNPs) of HIV-1 infection may provide important insights into mechanisms involved in viral control and pathogenesis. Here, our results suggest that the ribosomal protein lateral stalk subunit P1 (RPLP1) is expressed at higher levels in LTNPs compared to regular progressors (RPs). Functionally, RPLP1 inhibits transcription of clade B HIV-1 strains by occupying the C/EBPß binding sites in the viral long terminal repeat (LTR). This interaction requires the α-helixes 2 and 4 domains of RPLP1 and is evaded by HIV-1 group M subtype C and group N, O and P strains that do not require C/EBPß for transcription. We further demonstrate that HIV-1-induced translocation of RPLP1 from the cytoplasm to the nucleus is essential for antiviral activity. Finally, knock-down of RPLP1 promotes reactivation of latent HIV-1 proviruses. Thus, RPLP1 may play a role in the maintenance of HIV-1 latency and resistance to RPLP1 restriction may contribute to the effective spread of clade C HIV-1 strains.

Myeloid cannabinoid CB1 receptor deletion confers atheroprotection in male mice by reducing macrophage proliferation in a sex-dependent manner.

AIMS: Although the cannabinoid CB1 receptor has been implicated in atherosclerosis, its cell-specific effects in this disease are not well understood. To address this, we generated a transgenic mouse model to study the role of myeloid CB1 signaling in atherosclerosis. METHODS AND RESULTS: Here, we report that male mice with myeloid-specific Cnr1 deficiency on atherogenic background developed smaller lesions and necrotic cores than controls, while only minor genotype differences were observed in females. Male Cnr1 deficient mice showed reduced arterial monocyte recruitment and macrophage proliferation with less inflammatory phenotype. The sex-specific differences in proliferation were dependent on estrogen receptor (ER)α-estradiol signaling. Kinase activity profiling identified a CB1-dependent regulation of p53 and cyclin-dependent kinases. Transcriptomic profiling further revealed chromatin modifications, mRNA processing and mitochondrial respiration among the key processes affected by CB1 signaling, which was supported by metabolic flux assays. Chronic administration of the peripherally-restricted CB1 antagonist JD5037 inhibited plaque progression and macrophage proliferation, but only in male mice. Finally, CNR1 expression was detectable in human carotid endarterectomy plaques and inversely correlated with proliferation, oxidative metabolism and inflammatory markers, suggesting a possible implication of CB1-dependent regulation in human pathophysiology. CONCLUSION: Impaired macrophage CB1 signaling is atheroprotective by limiting their arterial recruitment, proliferation and inflammatory reprogramming in male mice. The importance of macrophage CB1 signaling appears to be sex-dependent.

Weight Indices, Cognition, and Mental Health From Childhood to Early Adolescence.

This cohort study evaluates the association between weight indices in childhood and changes in cognition and psychopathology.

Effect of Mechanical Damage in Green-Making Process on Aroma of Rougui Tea.

Rougui Tea (RGT) is a typical Wuyi Rock Tea (WRT) that is favored by consumers for its rich taste and varied aroma. The aroma of RGT is greatly affected by the process of green-making, but its mechanism is not clear. Therefore, in this study, fresh leaves of RGT in spring were picked, and green-making (including shaking and spreading) and spreading (unshaken) were, respectively, applied after sun withering. Then, they were analyzed by GC-TOF-MS, which showed that the abundance of volatile compounds with flowery and fruity aromas, such as nerolidol, jasmine lactone, jasmone, indole, hexyl hexanoate, (E)-3-hexenyl butyrate and 1-hexyl acetate, in green-making leaves, was significantly higher than that in spreading leaves. Transcriptomic and proteomic studies showed that long-term mechanical injury and dehydration could activate the upregulated expression of genes related to the formation pathways of the aroma, but the regulation of protein expression was not completely consistent. Mechanical injury in the process of green-making was more conducive to the positive regulation of the allene oxide synthase (AOS) branch of the α-linolenic acid metabolism pathway, followed by the mevalonate (MVA) pathway of terpenoid backbone biosynthesis, thus promoting the synthesis of jasmonic acid derivatives and sesquiterpene products. Protein interaction analysis revealed that the key proteins of the synthesis pathway of jasmonic acid derivatives were acyl-CoA oxidase (ACX), enoyl-CoA hydratase (MFP2), OPC-8:0 CoA ligase 1 (OPCL1) and so on. This study provides a theoretical basis for the further explanation of the formation mechanism of the aroma substances in WRT during the manufacturing process.

Molecular basis of bacterial DSR2 anti-phage defense and viral immune evasion.

Defense-associated sirtuin 2 (DSR2) systems are widely distributed across prokaryotic genomes, providing robust protection against phage infection. DSR2 recognizes phage tail tube proteins and induces abortive infection by depleting intracellular NAD+, a process that is counteracted by another phage-encoded protein, DSR Anti Defense 1 (DSAD1). Here, we present cryo-EM structures of Bacillus subtilis DSR2 in its apo, Tube-bound, and DSAD1-bound states. DSR2 assembles into an elongated tetramer, with four NADase catalytic modules clustered in the center and the regulatory-sensing modules distributed at four distal corners. Interestingly, monomeric Tube protein, rather than its oligomeric states, docks at each corner of the DSR2 tetramer to form a 4:4 DSR2-Tube assembly, which is essential for DSR2 NADase activity. DSAD1 competes with Tube for binding to DSR2 by occupying an overlapping region, thereby inhibiting DSR2 immunity. Thus, our results provide important insights into the assembly, activation and inhibition of the DSR2 anti-phage defense system.

Multiple E3 ligases act as antiviral factors against SARS-CoV-2 via inducing the ubiquitination and degradation of ORF9b.

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) open reading frame 9b (ORF9b) antagonizes the antiviral type I and III interferon (IFN) responses and is ubiquitinated and degraded via the ubiquitin-proteasome pathway. However, E3 ubiquitin ligases that mediate the polyubiquitination and degradation of ORF9b remain unknown. In this study, we identified 14 E3 ligases that specifically bind to SARS-CoV-2 ORF9b. Specifically, three E3 ligases, HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 (HUWE1), ubiquitin protein ligase E3 component n-recognin 4 (UBR4), and UBR5, induced K48-linked polyubiquitination and degradation of ORF9b, thereby attenuating ORF9b-mediated inhibition of the IFN response and SARS-CoV-2 replication. Moreover, each E3 ligase performed this function independent of the other two E3 ligases. Therefore, the three E3 ligases identified in this study as anti-SARS-CoV-2 host factors provide novel molecular insight into the virus-host interaction.IMPORTANCEUbiquitination is an important post-translational modification that regulates multiple biological processes, including viral replication. Identification of E3 ubiquitin ligases that target viral proteins for degradation can provide novel targets for antagonizing viral infections. Here, we identified multiple E3 ligases, including HECT, UBA, and WWE domain-containing E3 ubiquitin protein ligase 1 (HUWE1), ubiquitin protein ligase E3 component n-recognin 4 (UBR4), and UBR5, that ubiquitinated and induced the degradation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) open reading frame 9b (ORF9b), an interferon (IFN) antagonist, thereby enhancing IFN production and attenuating SARS-CoV-2 replication. Our study provides new possibilities for drug development targeting the interaction between E3 ligases and ORF9b.

Duck compound probiotics fermented diet alters the growth performance by shaping the gut morphology, microbiota and metabolism.

Dietary absorption and digestion are influenced by the microbiota, morphology, and digestive enzymes of intestines, and fermentation is a popular and effective technique to enhance animal rearing growth performance. This study aims to explore the pivotal role of Muscovy duck probiotics fermented feedstuff (FF) in altering the growth performance by reshaping gut morphology, microorganisms and metabolism. The findings showed that FF considerably raised the levels of fatty acids (FA) and small peptides (7-19AA) in the diet. Further feeding trial data reveals that FF greatly increased the Muscovy duck average daily gain (ADG) but had no effect on their daily feed intake (DFI), and the FCR significantly dropped (P < 0.05). Additionally, it was evident that FF improved the integrity of the intestinal mucosa in Muscovy duck by increasing villus height, villus height-to-crypt depth ratio, and lowering crypt depth. Then, in comparison to the control group (NC), there was a significant increase in the gene expression of the mucosal tight junction proteins Occludin, Claudin-1, and Zo-1 in the intestine of Muscovy duck. Additionally, there was higher expression of the mucosal transport channels SGLT-1, PepT1, AQP2, AQP3, and AQP10 in the similarly colon site, jejunum, and duodenum. Furthermore, in AB-PAS/PAS-stained duodenum, jejunum, ileum, and similarly colon site, FF markedly increased relative mucus output and goblet cells while decreasing epithelial cell apoptosis. Following 16S sequencing data indicated that the intestinal microbiota was altered and the diversity and richness of gut microbes was greatly enhanced by FF. Particularly, the boost of core probiotics, such as Rothia of duodenum, Limosilactobacillus and Lentilactobacillus of jejunum, Lactococcus and Rothia of ileum, Ligilactobacillus and Entocuccus of similarly colon site, Gallibacterium of caecum. And reduced potentially pathogenic bacteria (Campylobacter, Prevotellaceae, Clostridia-vadinBB60, and Oscillospira). Nontargeted metabolomics assay for intestinal content confirmed an increased organic acids (oxidanesulfonic acid, cholic acid, gallic acid, coumaric acid, pipecollc acid, 13s-hydroxyoctadecadienoic acid) and glycosides metabolites (5-hydroxydantrolene, 3-hydroxyguanfacine glucuronide, acetylleucine, astragalin, xanthosine, taxiphylin, sinapine, denudatine, penylalanyl-tyrosine and phenylalanyl-valine). These findings demonstrated that FF, a viable option to improve Muscovy duck growth performance through reconstructed intestinal morphology, microorganisms, and metabolism, subsequently promoted the gut health and increased diet digestion and absorption. The study that is being presented offers scientific proof that FF might be a useful strategy for improving Muscovy duck growth performance.

Transapical intramyocardial septal microwave ablation in treatment of hypertrophic obstructive cardiomyopathy: 12-month outcomes of a swine model.

BACKGROUND: To date, the extended Morrow procedure is considered the gold standard treatment for patients with obstructive hypertrophic cardiomyopathy who experience severe symptoms and are unresponsive to medication treatment. We therefore aimed to perform transapical intramyocardial septal microwave ablation to reduce the thickness of the interventricular septum myocardium in a minimally invasive method. METHODS: Fourteen swine were divided to form either a microwave ablation group (n = 7) or a sham group (n = 7). In the microwave ablation group, a transapical microwave antenna was inserted into the septum to ablate each myocardial segment at 40 W for 1 min, while in the sham group, the same operation was performed but without power output. We used echocardiography, electrocardiogram, during the operation. And added computerized tomography, cardiac nuclear magnetic resonance during follow-up. RESULTS: Segment hypokinesis was observed in all swine immediately following ablation. Compared with the sham group, the thickness of ablated segments in the ablation group decreased significantly 1 month post-operation (ablation group, 5.53 ± 1.00 mm vs. 8.03 ± 1.15 mm, respectively, P < 0.01; sham group, 8.40 ± 0.94 mm vs. 8.21 ± 1.09 mm, respectively, P = 0.081), and the outcome was still observed 1 year post-operation (ablation group, 3.36 ± 0.85 mm vs. 8.03 ± 1.15 mm, respectively, P < 0.01). No perforation of the septum was observed during the procedure or follow-up, and no heart failure or sudden cardiac death occurred during postoperative feeding. CONCLUSIONS: Transapical intramyocardial septal microwave ablation can effectively and safely produce a large region of necrosis. This technique can potentially mimic surgical myectomy while avoiding cardiopulmonary bypass and median sternotomy in high-risk hypertrophic obstructive cardiomyopathy patients.

Serine enrichment in tumors promotes regulatory T cell accumulation through sphinganine-mediated regulation of c-Fos.

CD4+ regulatory T (Treg) cells accumulate in the tumor microenvironment (TME) and suppress the immune system. Whether and how metabolite availability in the TME influences Treg cell differentiation is not understood. Here, we measured 630 metabolites in the TME and found that serine and palmitic acid, substrates required for the synthesis of sphingolipids, were enriched. A serine-free diet or a deficiency in Sptlc2, the rate-limiting enzyme catalyzing sphingolipid synthesis, suppressed Treg cell accumulation and inhibited tumor growth. Sphinganine, an intermediate metabolite in sphingolipid synthesis, physically interacted with the transcription factor c-Fos. Sphinganine c-Fos interactions enhanced the genome-wide recruitment of c-Fos to regions near the transcription start sites of target genes including Pdcd1 (encoding PD-1), which promoted Pdcd1 transcription and increased inducible Treg cell differentiation in vitro in a PD-1-dependent manner. Thus, Sptlc2-mediated sphingolipid synthesis translates the extracellular information of metabolite availability into nuclear signals for Treg cell differentiation and limits antitumor immunity.

Prediction of intraoperative red blood cell transfusion in valve replacement surgery: machine learning algorithm development based on non-anemic cohort.

Background: Our study aimed to develop machine learning algorithms capable of predicting red blood cell (RBC) transfusion during valve replacement surgery based on a preoperative dataset of the non-anemic cohort. Methods: A total of 423 patients who underwent valvular replacement surgery from January 2015 to December 2020 were enrolled. A comprehensive database that incorporated demographic characteristics, clinical conditions, and results of preoperative biochemistry tests was used for establishing the models. A range of machine learning algorithms were employed, including decision tree, random forest, extreme gradient boosting (XGBoost), categorical boosting (CatBoost), support vector classifier and logistic regression (LR). Subsequently, the area under the receiver operating characteristic curve (AUC), accuracy, recall, precision, and F1 score were used to determine the predictive capability of the algorithms. Furthermore, we utilized SHapley Additive exPlanation (SHAP) values to explain the optimal prediction model. Results: The enrolled patients were randomly divided into training set and testing set according to the 8:2 ratio. There were 16 important features identified by Sequential Backward Selection for model establishment. The top 5 most influential features in the RF importance matrix plot were hematocrit, hemoglobin, ALT, fibrinogen, and ferritin. The optimal prediction model was CatBoost algorithm, exhibiting the highest AUC (0.752, 95% CI: 0.662-0.780), which also got relatively high F1 score (0.695). The CatBoost algorithm also showed superior performance over the LR model with the AUC (0.666, 95% CI: 0.534-0.697). The SHAP summary plot and the SHAP dependence plot were used to visually illustrate the positive or negative effects of the selected features attributed to the CatBoost model. Conclusions: This study established a series of prediction models to enhance risk assessment of intraoperative RBC transfusion during valve replacement in no-anemic patients. The identified important predictors may provide effective preoperative interventions.

CRL4B E3 ligase recruited by PRPF19 inhibits SARS-CoV-2 infection by targeting ORF6 for ubiquitin-dependent degradation.

The accessory protein ORF6 of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a key interferon (IFN) antagonist that strongly suppresses the production of primary IFN as well as the expression of IFN-stimulated genes. However, how host cells respond to ORF6 remains largely unknown. Our research of ORF6-binding proteins by pulldown revealed that E3 ligase components such as Cullin 4B (CUL4B), DDB1, and RBX1 are potential ORF6-interacting proteins. Further study found that the substrate recognition receptor PRPF19 interacts with CUL4B, DDB1, and RBX1 to form a CRL4B-based E3 ligase, which catalyzes ORF6 ubiquitination and subsequent degradation. Overexpression of PRPF19 promotes ORF6 degradation, releasing ORF6-mediated IFN inhibition, which inhibits SARS-CoV-2 replication. Moreover, we found that activation of CUL4B by the neddylation inducer etoposide alleviates lung lesions in a SARS-CoV-2 mouse infection model. Therefore, targeting ORF6 for degradation may be an effective therapeutic strategy against SARS-CoV-2 infection.IMPORTANCEThe cellular biological function of the ubiquitin-proteasome pathway as an important modulator for the regulation of many fundamental cellular processes has been greatly appreciated. The critical role of the ubiquitin-proteasome pathway in viral pathogenesis has become increasingly apparent. It is a powerful tool that host cells use to defend against viral infection. Some cellular proteins can function as restriction factors to limit viral infection by ubiquitin-dependent degradation. In this research, we identificated of CUL4B-DDB1-PRPF19 E3 Ubiquitin Ligase Complex can mediate proteasomal degradation of ORF6, leading to inhibition of viral replication. Moreover, the CUL4B activator etoposide alleviates disease development in a mouse infection model, suggesting that this agent or its derivatives may be used to treat infections caused by SARS-CoV-2. We believe that these results will be extremely useful for the scientific and clinic communities in their search for cues and preventive measures to combat the COVID-19 pandemic.

Magnetite-boosted syntrophic conversion of acetate to methane during thermophilic anaerobic digestion.

Using a batch thermophilic anaerobic system established with 60 mL serum bottles, the mechanism on how microbial enrichments obtained from magnetite-amended paddy soil via repeated batch cultivation affected methane production from acetate was investigated. Magnetite-amended enrichments (MAEs) can improve the methane production rate rather than the methane yield. Compared with magnetite-unamended enrichments, the methane production rate in MAE was improved by 50%, concomitant with the pronounced electrochemical response, high electron transfer capacity, and fast acetate degradation. The promoting effects might be ascribed to direct interspecies electron transfer facilitated by magnetite, where magnetite might function as electron conduits to link the acetate oxidizers (Anaerolineaceae and Peptococcaceae) with methanogens (Methanosarcinaceae). The findings demonstrated the potential application of MAE for boosting methanogenic performance during thermophilic anaerobic digestion.

Deubiquitinase USP1 regulates sarbecovirus ORF6 protein function.

SARS-CoV-2 belongs to the subgenus Sarbecovirus, which universally encodes the accessory protein ORF6. SARS-CoV-2 ORF6 is an antagonist of the interferon (IFN)-mediated antiviral response and plays an important role in viral infections. However, the mechanism by which the host counteracts the function of ORF6 to restrict viral replication remains unclear. In this study, we found that most ORF6 proteins encoded by sarbecoviruses could be ubiquitinated and subsequently degraded via the proteasome pathway. Through extensive screening, we identified that the deubiquitinase USP1, which effectively and broadly deubiquitinates sarbecovirus ORF6 proteins, stabilizes ORF6 proteins, resulting in enhanced viral replication. Therefore, ubiquitination and deubiquitination of ORF6 are important for antagonizing IFN-mediated antiviral signaling and influencing the virulence of SARS-CoV-2. These findings highlight an essential molecular mechanism and may provide a novel target for therapeutic interventions against viral infections.IMPORTANCEThe ORF6 proteins encoded by sarbecoviruses are essential for effective viral replication and infection and are important targets for developing effective intervention strategies. In this study, we confirmed that sarbecovirus ORF6 proteins are important antagonists of the host immune response and identified the regulatory mechanisms of ubiquitination and deubiquitination of most sarbecovirus ORF6 proteins. Moreover, we revealed that DUB USP1 prevents the proteasomal degradation of all ORF6 proteins, thereby promoting the virulence of SARS-CoV-2. Thus, impeding ORF6 function is helpful for attenuating the virulence of sarbecoviruses. Therefore, our findings provide a deeper understanding of the molecular mechanisms underlying sarbecovirus infections and offer potential new therapeutic targets for the prevention and treatment of these infections.

Utilization of an Artery-on-a-Chip to Unravel Novel Regulators and Therapeutic Targets in Vascular Diseases.

In this study, organ-on-chip technology is used to develop an in vitro model of medium-to-large size arteries, the artery-on-a-chip (AoC), with the objective to recapitulate the structure of the arterial wall and the relevant hemodynamic forces affecting luminal cells. AoCs exposed either to in vivo-like shear stress values or kept in static conditions are assessed to generate a panel of novel genes modulated by shear stress. Considering the crucial role played by shear stress alterations in carotid arteries affected by atherosclerosis (CAD) and abdominal aortic aneurysms (AAA) disease development/progression, a patient cohort of hemodynamically relevant specimens is utilized, consisting of diseased and non-diseased (internal control) vessel regions from the same patient. Genes activated by shear stress follow the same expression pattern in non-diseased segments of human vessels. Single cell RNA sequencing (scRNA-seq) enables to discriminate the unique cell subpopulations between non-diseased and diseased vessel portions, revealing an enrichment of flow activated genes in structural cells originating from non-diseased specimens. Furthermore, the AoC served as a platform for drug-testing. It reproduced the effects of a therapeutic agent (lenvatinib) previously used in preclinical AAA studies, therefore extending the understanding of its therapeutic effect through a multicellular structure.