Potential Regulatory Networks and Heterosis for Flavonoid and Terpenoid Contents in Pak Choi: Metabolomic and Transcriptome Analyses.

Pak choi exhibits a diverse color range and serves as a rich source of flavonoids and terpenoids. However, the mechanisms underlying the heterosis and coordinated regulation of these compounds-particularly isorhamnetin-remain unclear. This study involved three hybrid combinations and the detection of 528 metabolites from all combinations, including 26 flavonoids and 88 terpenoids, through untargeted metabolomics. Analysis of differential metabolites indicated that the heterosis for the flavonoid and terpenoid contents was parent-dependent, and positive heterosis was observed for isorhamnetin in the two hybrid combinations (SZQ, 002 and HMG, ZMG). Moreover, there was a high transcription level of flavone 3'-O-methyltransferase, which is involved in isorhamnetin biosynthesis. The third group was considered the ideal hybrid combination for investigating the heterosis of flavonoid and terpenoid contents. Transcriptome analysis identified a total of 12,652 DEGs (TPM > 1) in various groups that were used for comparison, and DEGs encoding enzymes involved in various categories, including "carotenoid bio-synthesis" and "anthocyanin biosynthesis", were enriched in the hybrid combination (SZQ, 002). Moreover, the category of anthocyanin biosynthesis also was enriched in the hybrid combination (HMG, ZMG). The flavonoid pathway demonstrated more differential metabolites than the terpenoid pathway did. The WGCNA demonstrated notable positive correlations between the dark-green modules and many flavonoids and terpenoids. Moreover, there were 23 ERF genes in the co-expression network (r ≥ 0.90 and p < 0.05). Thus, ERF genes may play a significant role in regulating flavonoid and terpenoid biosynthesis. These findings enhance our understanding of the heterosis and coordinated regulation of flavonoid and terpenoid biosynthesis in pak choi, offering insights for genomics-based breeding improvements.

Elaborate Report of Allium sativum Clove Brown Rot Caused by Fusarium solani in China.

In September 2023, brown rot disease was observed on cloves of garlic (Allium sativum) variety "Zipi-1" (purple skin) collected from Jinxiang County, China during scientific research at the Beijing Academy of Agricultural and Forestry Sciences after being planted in nutrient soil for approximately 2 weeks in a growth chamber maintaining 22℃, 60% relative humidity, and 16 hours of light. Out of the 90 garlic cloves investigated, 18 showed signs of decay, characterized by a brown color and rot, with the surface covered in blue and white mold layers. Six symptomatic cloves were collected for isolating the pathogen using the method described in a previous study (Wu et al. 2021). After 2 d of incubation, individual spores were harvested from the fungal colonies and recultured. Single-spore cultures growing on PDA medium appeared white and flocculent when viewed from the top, and yellowish-brown when viewed from the bottom. After 5 d of cultivation, the colonies had a diameter of approximately 5.8 cm and microscopic examination revealed that the mycelium had a diameter of about 9-13 µm (Fig. S1a, b and c). Isolate As1 produced three types of spores: oval-shaped chlamydospores with a diameter of approximately 6 µm, while spindle-shaped microconidia and sickle-shaped macroconidia measuring approximately 6-7 × 20-30 µm and 8 × 50 µm, respectively (Fig. S1d and e). The mycelial characteristics and reproductive structures of the isolates fit the morphological description of Fusarium solani (Xie et al. 2022). To confirm the identification, TEF1, RPB1 and RPB2 regions of the genome were amplified from three separate isolates (As1, As2, and As3) using EF1/EF2, RPB1-Fa/G2R, RPB2-5F2/7cR, and RPB2-7cF/11aR primer pairs (O'Donnell et al. 2022). The results indicated that the sequences of the three isolates were completely identical. Furthermore, the BLASTn comparison results of the TEF1 (OR916018, 710bp, 100%), RPB1 (OR916019, 1797bp, 99.8%), and RPB2 (OR916020, 1874bp, 100%) sequences in the FUSARIUM-ID v.3.0 database revealed that As1 was identified as F. solani species complex 5 (O'Donnell et al. 2022). To assess the pathogenicity of As1, the surface of healthy garlic cloves (n = 30) was spread with 106 microconidia/mL As1 suspension, while a control group (n = 30) was inoculated with sterile water. All inoculated cloves were placed in an artificial climate chamber under same conditions described above. After 10 d, all inoculated cloves exhibited rot symptoms consistent with those of the initially infected cloves identified in September 2023, while the control plant cloves remained asymptomatic (Fig. S2). Based on morphological and molecular characters (TEF1, RPB1, and RPB2), the reisolated pathogen from diseased plants was identical to the As1 isolate used for inoculation, and the disease assays were repeated twice. Fusarium spp. has been reported as the causal agent of garlic rot disease in several countries such as Mexico, America, and Russia (Gálvez and Palmero 2022). Tai (1979) previously published a report on the presence of F. solani in garlic; however, the content in the book is rather basic, lacking detailed information on the isolation, identification, and the potential for causing garlic diseases, whether postharvest or during growth. Our research can be considered a supplement and improvement to the study by Tai (1979) and lays the groundwork for future studies on management strategies to combat plant diseases caused by F. solani.

[Identification and expression analysis of whole gene family of Isatis indigotica 4-coumarate: CoA ligase].

The 4-coumarate: CoA ligase(4CL) is a key enzyme in the upstream pathway of phenylpropanoids such as flavonoids, soluble phenolic esters, lignans, and lignins in plants. In this study, 13 4CL family members of Arabidopsis thaliana were used as reference sequences to identify the 4CL gene family candidate members of Isatis indigotica from the reported I. indigotica genome. Further bioinformatics analysis and analysis of the expression pattern of 4CL genes and the accumulation pattern of flavonoids were carried out. Thirteen 4CL genes were obtained, named Ii4CL1-Ii4CL13, which were distributed on chromosomes 1, 2, 3, 4, and 6. The analysis of the gene structure and conserved structural domains revealed the intron number of I. indigotica 4CL genes was between 1 and 12 and the protein structural domains were highly conserved. Cis-acting element analysis showed that there were multiple response elements in the promoter sequence of I. indigotica 4CL gene family, and jasmonic acid had the largest number of reaction elements. The collinearity analysis showed that there was a close relationship between the 4CL gene family members of I. indigotica and A. thaliana. As revealed by qPCR results, the expression analysis of the 4CL gene family showed that 10 4CL genes had higher expression levels in the aboveground part of I. indigotica. The content assay of flavonoids in different parts of I. indigotica showed that flavonoids were mainly accumulated in the aboveground part of plants. This study provides a basis for further investigating the roles of the 4CL gene family involved in the biosynthesis of flavonoids in I. indigotica.

The relationship between dysphagia and frailty among Chinese hospitalized older patients: a serial mediation model through self-perceived oral health and self-reported nutritional status.

BACKGROUND: Frailty contributes to adverse outcomes in older adults and places a heavy burden on healthcare resources. Dysphagia is associated with frailty, but the mechanisms by which dysphagia affects frailty in older adults are unclear. This study aimed to investigate a serial mediating effect of self-perceived oral health and self-reported nutritional status in the relationship between dysphagia and frailty among hospitalized older patients in China. METHODS: This cross-sectional study included 1200 patients aged ≥ 65 years in the Department of Geriatrics, Shaanxi Provincial People's Hospital. A structured face-to-face interview was used to survey the following questionnaires: General Information Questionnaire, Tilburg Frailty Indicators (TFI), Eating Assessment Tool-10 (EAT-10), 30mL Water Swallow Test (WST), Geriatric Oral Health Assessment Index (GOHAI), and Short-Form Mini-Nutritional Assessment (MNA-SF). A total of 980 participants with complete data were included in the analysis. Statistical analysis was performed using SPSS 26.0 and Amos 28.0 software. Spearman's correlation analysis was used for correlation analysis of study variables. The results of the multivariate linear regression analysis for frailty were used as covariates in the mediation analysis, and the structural equation model (SEM) was used to analyze the mediating effects among the study variables. RESULTS: Dysphagia, self-perceived oral health, self-reported nutritional status, and frailty were significantly correlated (P<0.001). Dysphagia was found to directly affect frailty (ß = 0.161, 95%CI = 0.089 to 0.235) and through three significant mediation pathways: (1) the path through self-perceived oral health (ß = 0.169, 95%CI = 0.120 to 0.221), accounting for 36.98% of the total effect; (2) the path through self-reported nutritional status (ß = 0.050, 95%CI = 0.023 to 0.082), accounting for 10.94% of the total effect; (3) the path through self-perceived oral health and self-reported nutritional status (ß = 0.077, 95%CI = 0.058 to 0.102), accounting for 16.85% of the total effect. The total mediation effect was 64.77%. CONCLUSIONS: This study indicated that dysphagia was significantly associated with frailty. Self-perceived oral health and self-reported nutritional status were serial mediators of this relationship. Improving the oral health and nutritional status of hospitalized older patients may prevent or delay the frailty caused by dysphagia.

Chitosan-crosslinked polyvinyl alcohol anti-swelling hydrogel designed to prevent abdominal wall adhesion.

Abdominal adhesion is a frequent clinical issue with a high incidence rate and consequences following intra-abdominal surgery. Although many anti-adhesion materials have been used in surgical procedures, additional research is still needed to determine which ones have the most robust wet tissue adhesion, the best anti-postoperative adhesion, and the best anti-inflammatory properties. We have developed an excellent tissue adhesion and anti-swelling polyvinyl alcohol-chitosan hydrogel (AS hydrogel). According to in vitro cell testing, AS hydrogel significantly decreased inflammation around cells and exhibited good biocompatibility. Further, we assessed how well AS hydrogel prevented intraperitoneal adhesion using a rabbit model with cecum and abdominal wall injuries. According to the data, AS hydrogel has excellent anti-inflammatory and biodegradability properties compared to the control group. It can also prevent intestinal and abdominal wall injuries from occurring during surgery. Based on these results, hydrogel appears to be a perfect new material to prevent postoperative abdominal wall adhesion.

Comparative Study of the Structure and Height of CH4 Laminar Diffusion Flames: Effects of Fuel-Side versus Air-Side Dilution.

The strategy for introducing diluents is a critical practical concern in diluted combustion; however, a comprehensive understanding of the effects of fuel-side dilution versus air-side dilution is currently lacking. This numerical investigation systematically studied the effects of dilution strategies on methane coflow diffusion flames, with a focus on the flame structure and flame length. Common additives in practical combustion, specifically H2O and CO2, were introduced to either the fuel or the air streams, with dilution ratios (Z) ranging from 0 to 0.2, and the impacts of four dilution strategies were quantified and ranked. Detailed simulations were conducted using a well-validated two-dimensional (2D) flame code to gain a deep understanding of OH formation, flame attachment, temperature of the burner nozzle, and flame height. Systematic analyses in terms of heat transfer, molecular diffusion, and chemical kinetics were conducted. Results demonstrate that introducing diluents into the air stream exerts a more profound influence on suppressing OH formation compared with fuel-side dilution. Moreover, air-side dilution has a negligible influence on flame attachment, while increasing Z on fuel side significantly inhibits flame attachment, and the latter behavior is attributed to the diminished mass diffusion of CH4 toward the oxidizer side. As the flame attachment weakens, it causes a consequential reduction in heat transfer from the flame base to the burner. Accordingly, the nozzle temperature exhibits a more remarkable decrease with the fuel-side dilution ratio than with the air-side dilution ratio. Simultaneously, a more profound influence of Z on flame length was observed for fuel-side dilution than for air-side dilution, and the underlying mechanisms governing these two distinct dilution strategies were theoretically elucidated.

Biological control of wheat powdery mildew disease by the termite-associated fungus Aspergillus chevalieri BYST01 and potential role of secondary metabolites.

BACKGROUND: Wheat powdery mildew, caused by the biotrophic pathogen Blumeria graminis f. sp. tritici (Bgt) is a serious fungal disease. Natural metabolites produced by microorganisms are beneficial biological control agents to inhibit Bgt. In the present study, we investigated the effects of Aspergillus chevalieri BYST01 on wheat powdery mildew. RESULTS: A strain isolated from the termite was identified as A. chevalieri BYST01 by morphological characteristics and phylogenetic analysis. The fermentation broth of BYST01 showed good biocontrol effect on the Bgt in vivo with the control efficiencies of 81.59% and 71.34% under the protective and therapeutic tests, respectively. Four known metabolites, including the main compound physcion (30 mg/L), were isolated from the fermentation broth of BYST01 extracted with ethyl acetate. Importantly, under a concentration of 0.1 mM, physcion repressed conidial germination of Bgt with an inhibition rate of 77.04% in vitro and showed important control efficiencies of 80.36% and 74.64% in vivo under the protective and therapeutic tests, respectively. Hence, the BYST01 showed important potential as a microbial cell factory for the high yield of the green natural fungicide physcion. Finally, the biosynthetic gene clusters responsible for physicon production in BYST01 was predicted by analyzing a chromosome-scale genome obtained using a combination of Illumina, PacBio, and Hi-C sequencing technologies. CONCLUSION: Aspergillus chevalieri BYST01 and its main metabolite physcion had a significant control effect on wheat powdery mildew. The biosynthesis pathway of physcion in BYST01 was predicted. © 2023 Society of Chemical Industry.

Urolithin B Attenuates Cerebral Ischemia-reperfusion Injury by Modulating Nrf2-regulated Anti-oxidation in Rats.

Ischemia-reperfusion (IR) induces a wide range of irreversible injuries. Cerebral IR injury (IRI) refers to additional brain tissue damage that occurs after blood flow is restored following cerebral ischemia. Currently, no established methods exist for treating IRI. Oxidative stress is recognized as a primary mechanism initiating IRI and a crucial focal target for its treatment. Urolithin B, a metabolite derived from ellagitannins, antioxidant polyphenols, has demonstrated protective effects against oxidative stress in various disease conditions. However, the precise mechanism underlying UB's effect on IRI remains unclear. In our current investigation, we assessed UB's ability to mitigate neurological functional impairment induced by IR using a neurological deficit score. Additionally, we examined cerebral infarction following UB administration through TTC staining and neuron Nissl staining. UB's inhibition of neuronal apoptosis was demonstrated through the TUNEL assay and Caspase-3 measurement. Additionally, we examined UB's effect on oxidative stress levels by analyzing malondialdehyde (MDA) concentration, superoxide dismutase (SOD) activity, and immunohistochemistry analysis of inducible nitric oxide synthase (iNOS) and 8-hydroxyl-2'-deoxyguanosine (8-OHdG). Notably, UB demonstrated a reduction in oxidative stress levels. Mechanistically, UB was found to stimulate the Nrf2/HO-1 signaling pathway, as evidenced by the significant reduction in UB's neuroprotective effects upon administration of ATRA, an Nrf2 inhibitor. In summary, UB effectively inhibits oxidative stress induced by IR through the activation of the Nrf2/HO-1 signaling pathway. These findings suggest that UB holds promise as a therapeutic agent for the treatment of IRI.

Spatiotemporal variations and its driving factors of NDVI in Northwest China during 2000-2021.

Northwest China (WTL) is an essential ecological barrier zone of China, an important node of the "Silk Road Economic Belt," and a crucial bearing area for China's execution of the "One Road and One Belt" and "Going Global" strategies. However, its ecology is exceedingly fragile and particularly vulnerable to climate change and human interference. This study explored the spatiotemporal evolution characteristics of vegetation in WTL using NDVI data and investigated its drive mechanisms by geodetector, partial correlation analysis, and residual trend analysis methods. As well as forecasting the trend for vegetation changes. The findings demonstrated that (1) the change in NDVI manifested an overall improvement trend and the distribution in space of NDVI rose from the center to the periphery. 57.07% of the area had a sparse cover of vegetation (NDVI between 0 and 0.2). In addition, about 49% of regions had deterioration tendencies, which were mainly aggregated in HX, QCXDB, QCXDN, and the eastern of QCXQN and QCXXB. (2) The NDVI's shifting trend was unsustainability, and the region of uncertain future accounted for 57.45% of the total, with apparent unsustainability features. (3) The key parameters influencing NDVI spatial distribution were Pre (precipitation), vegetation type, land use type, and soil type. The interaction between two factors enhanced the influence of any single element, which appeared as bivariate and nonlinear enhancements. (4) Both climate variations and human activities have been recognized as key variables affecting NDVI growth. NDVI variance in 73.02% of areas was influenced by the combined effects of climate variations and human activities. However, human activities were the most influential element in NDVI growth, with the relative contributions of 80.28% (19.72% of which was caused by climate variations). These results can be conducive to deepening insights into the local vegetation status, identifying the mechanisms driving vegetation change, and providing scientific recommendations for WTL's ecosystem restoration measures based on actual situations.

Mutant RB1 enhances therapeutic efficacy of PARPis in lung adenocarcinoma by triggering the cGAS/STING pathway.

Poly (ADP-ribose) polymerase inhibitors (PARPis) are approved for cancer therapy according to their synthetic lethal interactions, and clinical trials have been applied in non-small cell lung cancer. However, the therapeutic efficacy of PARPis in lung adenocarcinoma (LUAD) is still unknown. We explored the effect of a mutated retinoblastoma gene (RB1) on PARPi sensitivity in LUAD. Bioinformatic screening was performed to identify PARPi-sensitive biomarkers. Here, we showed that viability of LUAD cell lines with mutated RB1 was significantly decreased by PARPis (niraparib, rucaparib, and olaparib). RB1 deficiency induced genomic instability, prompted cytosolic double-stranded DNA (dsDNA) formation, activated the cGAS/STING pathway, and upregulated downstream chemokines CCL5 and CXCL10, triggering immune cell infiltration. Xenograft experiments indicated that PARPi treatment reduced tumorigenesis in RB1-KO mice. Additionally, single-cell RNA sequencing analysis showed that malignant cells with downregulated expression of RB1 had more communications with other cell types, exhibiting activation of specific signaling such as GAS, IFN response, and antigen-presenting and cytokine activities. Our findings suggest that RB1 mutation mediates the sensitivity to PARPis through a synthetic lethal effect by triggering the cGAS/STING pathway and upregulation of immune infiltration in LUAD, which may be a potential therapeutic strategy.

Heterogeneous catalytic oxidation of glycerol over a UiO-66-derived ZrO2@C supported Au catalyst at room temperature.

The catalytic conversion of biomass-derived glycerol into high-value-added products, such as glyceric acid (GLYA), using catalyst-supported Au nanoparticles (Au NPs) at room temperature presents a significant challenge. In this study, we constructed a series of supported Au catalysts, including Au/ZrO2@C, Au/C, Au/ZrO2, and Au/ZrO2-C, and investigated their effectiveness in selectively catalytic oxidizing glycerol to GLYA at room temperature. Among these catalysts, the Au/ZrO2@C catalyst exhibited the best catalytic performance, achieving a glycerol conversion rate of 73% and a GLYA selectivity of 79% under the optimized reaction conditions (reaction conditions: 30 mL 0.1 M glycerol, glycerol/Au = 750 mol mol-1, T = 25 °C, p(O2) = 10 bar, stirring speed = 600 rpm, time = 6 h). Physical adsorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and other characterization methods were employed to analyze the texture properties of the catalyst. The findings indicated that the support structure, the strong metal-support interactions between Au NPs and the support, and the presence of small metallic Au NPs were the primary factors contributing to the catalyst's high activity and selectivity. Moreover, the reusability of the Au/ZrO2@C catalyst was investigated, and a probable reaction mechanism for the oxidation of glycerol was proposed.

3D-Printed lattice-inspired composites for bone reconstruction.

Mechanical performance is crucial for biomedical applications of scaffolds. In this study, the stress distribution of six lattice-inspired structures was investigated using finite element simulations, and scaffolds with pre-designed structures were prepared using selective laser sintering (SLS) technology. The results showed that scaffolds with face-centered cubic (FCC) structures exhibited the highest compressive strength. Moreover, scaffolds composed of polylactic acid/anhydrous calcium hydrogen phosphate (PLA/DCPA) showed good mechanical properties and bioactivity. An in vitro study showed that these scaffolds promoted cell proliferation significantly and showed excellent osteogenic performance. Composite scaffolds with FCC structures are promising for bone tissue engineering.

Downregulated calmodulin expression contributes to endothelial cell impairment in diabetes.

Endothelial dysfunction, a central hallmark of cardiovascular pathogenesis in diabetes mellitus, is characterized by impaired endothelial nitric oxide synthase (eNOS) and NO bioavailability. However, the underlying mechanisms remain unclear. Here in this study, we aimed to identify the role of calmodulin (CaM) in diabetic eNOS dysfunction. Human umbilical vein endothelial cells and murine endothelial progenitor cells (EPCs) treated with high glucose (HG) exhibited downregulated CaM mRNA/protein and vascular endothelial growth factor (VEGF) expression with impeded eNOS phosphorylation and cell migration/tube formation. These perturbations were reduplicated in CALM1-knockdown cells but prevented in CALM1-overexpressing cells. EPCs from type 2 diabetes animals behaved similarly to HG-treated normal EPCs, which could be rescued by CALM1-gene transduction. Consistently, diabetic animals displayed impaired eNOS phosphorylation, endothelium-dependent dilation, and CaM expression in the aorta, as well as deficient physical interaction of CaM and eNOS in the gastrocnemius. Local CALM1 gene delivery into a diabetic mouse ischemic hindlimb improved the blunted limb blood perfusion and gastrocnemius angiogenesis, and foot injuries. Diabetic patients showed insufficient foot microvascular autoregulation, eNOS phosphorylation, and NO production with downregulated CaM expression in the arterial endothelium, and abnormal CALM1 transcription in genome-wide sequencing analysis. Therefore, our findings demonstrated that downregulated CaM expression is responsible for endothelium dysfunction and angiogenesis impairment in diabetes, and provided a novel mechanism and target to protect against diabetic endothelial injury.

Genome-Wide Analysis of the BAHD Family in Welsh Onion and CER2-LIKEs Involved in Wax Metabolism.

BAHD acyltransferases (BAHDs), especially those present in plant epidermal wax metabolism, are crucial for environmental adaptation. Epidermal waxes primarily comprise very-long-chain fatty acids (VLCFAs) and their derivatives, serving as significant components of aboveground plant organs. These waxes play an essential role in resisting biotic and abiotic stresses. In this study, we identified the BAHD family in Welsh onion (Allium fistulosum). Our analysis revealed the presence of AfBAHDs in all chromosomes, with a distinct concentration in Chr3. Furthermore, the cis-acting elements of AfBAHDs were associated with abiotic/biotic stress, hormones, and light. The motif of Welsh onion BAHDs indicated the presence of a specific BAHDs motif. We also established the phylogenetic relationships of AfBAHDs, identifying three homologous genes of CER2. Subsequently, we characterized the expression of AfCER2-LIKEs in a Welsh onion mutant deficient in wax and found that AfCER2-LIKE1 plays a critical role in leaf wax metabolism, while all AfCER2-LIKEs respond to abiotic stress. Our findings provide new insights into the BAHD family and lay a foundation for future studies on the regulation of wax metabolism in Welsh onion.

Bismuth Nanoparticle-Embedded Carbon Microrod for High-Rate Electrochemical Magnesium Storage.

Bismuth metal is regarded as a promising magnesium storage anode material for magnesium-ion batteries due to its high theoretical volumetric capacity and a low alloying potential versus magnesium metal. However, the design of highly dispersed bismuth-based composite nanoparticles is always used to achieve efficient magnesium storage, which is adverse to the development of high-density storage. Herein, a bismuth nanoparticle-embedded carbon microrod (Bi⊂CM), which is prepared via annealing of the bismuth metal-organic framework (Bi-MOF), is developed for high-rate magnesium storage. The use of the Bi-MOF precursor synthesized at an optimized solvothermal temperature of 120 °C benefits the formation of the Bi⊂CM-120 composite with a robust structure and a high carbon content. As a result, the as-prepared Bi⊂CM-120 anode compared to pure Bi and other Bi⊂CM anodes exhibits the best rate performance of magnesium storage at various current densities from 0.05 to 3 A g-1. For example, the reversible capacity of the Bi⊂CM-120 anode at 3 A g-1 is ∼17 times higher than that of the pure Bi anode. This performance is also competitive among those of the previously reported Bi-based anodes. Importantly, the microrod structure of the Bi⊂CM-120 anode material remained upon cycling, indicative of good cycling stability.

Cystathionine-γ-lyase attenuates inflammatory response and pain of osteoarthritis.

The chronic articular disease osteoarthritis (OA) is characterized by osteophyte generation, subchondral bone remodeling, and cartilage deterioration. Low levels of H2S catalyzed by cystathionine-γ-lyase (CSE) encoded by Cthhas neuroprotective, cardioprotective, anti-apoptotic, and anti-inflammatory effects thus, Cth is being developed as a potential therapy for the management of the pathogenesis and symptoms of osteoarthritis. Single-cell RNA sequencing (scRNA-seq) and immunohistochemistry of human cartilage revealed that the expression of CTH was decreased in OA patients. We found that Cthoverexpression decrease IL-1ß-induced overactivation of the NF-κB signaling pathway. In vivo, Cthoverexpression relieved pain response and cartilage damage in the anterior cruciate ligament transection (ACLT) rat model. In vitro, CSE alleviated chondrocytes catabolism, inflammation, apoptosis, and senescence, and suppressed the NF-κB pathway. We postulate that CSE has therapeutic effects in suppressing inflammation and degeneration in OA and should be further investigated clinically.

Improving tyrosol production efficiency through shortening the allosteric signal transmission distance of pyruvate decarboxylase.

Tyrosol is an important chemical in medicine and chemical industries, which can be synthesized by a four-enzyme cascade pathway constructed in our previous study. However, the low catalytic efficiency of pyruvate decarboxylase from Candida tropicalis (CtPDC) in this cascade is a rate-limiting step. In this study, we resolved the crystal structure of CtPDC and investigated the mechanism of allosteric substrate activation and decarboxylation of this enzyme toward 4-hydroxyphenylpyruvate (4-HPP). In addition, based on the molecular mechanism and structural dynamic changes, we conducted protein engineering of CtPDC to improve decarboxylation efficiency. The conversion of the best mutant, CtPDCQ112G/Q162H/G415S/I417V (CtPDCMu5), had over two-fold improvement compared to the wild-type. Molecular dynamic (MD) simulation revealed that the key catalytic distances and allosteric transmission pathways were shorter in CtPDCMu5 than in the wild type. Furthermore, when CtPDC in the tyrosol production cascade was replaced with CtPDCMu5, the tyrosol yield reached 38 g·L-1 with 99.6% conversion and 1.58 g·L-1·h-1 space-time yield in 24 h through further optimization of the conditions. Our study demonstrates that protein engineering of the rate-limiting enzyme in the tyrosol synthesis cascade provides an industrial-scale platform for the biocatalytic production of tyrosol. KEY POINTS: • Protein engineering of CtPDC based on allosteric regulation improved the catalytic efficiency of decarboxylation. • The application of the optimum mutant of CtPDC removed the rate-limiting bottleneck in the cascade. • The final titer of tyrosol reached 38 g·L-1 in 24 h in 3 L bioreactor.

Xp22.31 copy number variations in 87 fetuses: refined genotype-phenotype correlations by prenatal and postnatal follow-up.

BACKGROUND: Xp22.31 deletion and duplication have been described in various studies, but different laboratories interpret pathogenicity differently. OBJECTIVES: Our study aimed to refine the genotype-phenotype associations between Xp22.31 copy number variants in fetuses, with the aim of providing data support to genetic counseling. METHODS: We retrospectively analyzed karyotyping and single nucleotide polymorphism array results from 87 fetuses and their family members. Phenotypic data were obtained through follow-up visits. RESULTS: The percentage of fetuses carrying the Xp22.31 deletions (9 females, 12 males) was 24.1% (n = 21), while duplications (38 females, 28 males) accounted for 75.9% (n = 66). Here, we noted that the typical region (from 6.4 to 8.1 Mb, hg19) was detected in the highest ratio, either in the fetuses with deletions (76.2%, 16 of 21) or duplications (69.7%, 46 of 66). In female deletion carriers, termination of pregnancy was chosen for two fetuses, and the remaining seven were born without distinct phenotypic abnormalities. In male deletion carriers, termination of pregnancy was chosen for four fetuses, and the remaining eight of them displayed ichthyosis without neurodevelopmental anomalies. In two of these cases, the chromosomal imbalance was inherited from the maternal grandfathers, who also only had ichthyosis phenotypes. Among the 66 duplication carriers, two cases were lost at follow-up, and pregnancy was terminated for eight cases. There were no other clinical findings in the rest of the 56 fetuses, including two with Xp22.31 tetrasomy, for either male or female carriers. CONCLUSION: Our observations provide support for genetic counseling in male and female carriers of Xp22.31 copy number variants. Most of them are asymptomatic in male deletion carriers, except for skin findings. Our study is consistent with the view that the Xp22.31 duplication may be a benign variant in both sexes.

Clinical application of noninvasive prenatal testing in twin pregnancies: a single-center experience.

OBJECTIVES: To evaluate the clinical efficiency of noninvasive prenatal testing (NIPT) for fetal chromosomal aneuploidy screening in twin pregnancies. METHODS: A total of 1650 women with twin pregnancies were enrolled in the study, which underwent NIPT at the Southwest Hospital, Army Medical University, Chongqing, China from January 2013 to June 2022. Fetal karyotyping analysis was conducted in high-risk patients, with subsequent follow-up on pregnancy outcomes. RESULTS: In 1650 pregnancies, NIPT results showed ten cases of the fetal chromosome aneuploidy, of which six cases were true positive and four cases were false positive. The sensitivity, specificity, positive predictive value (PPV), and false-positive rate (FPR) of trisomy 21 were 100%, 99.79%, 57.14%, and 0.18%, respectively. Sensitivity, specificity, PPV, and FPR of trisomy 18 were 100%, 99.94%, 50%, and 0.06%, respectively. The sensitivity, specificity, PPV, and FPR of trisomy 13 were 100%, 100%, 100%, and 0%, respectively. No false negatives were detected and the negative predictive value (NPV) was 100% of the total. Eleven pregnancies failed the NIPT test with no-call due to the low fetal fraction (< 4%). CONCLUSIONS: NIPT is a high-performing routine primary prenatal screening test in twin pregnancies, with high sensitivity and specificity in screening for fetal aneuploidy.

Targeting the TNF-α-TNFR interaction with EGCG to block NF-κB signaling in human synovial fibroblasts.

The tumor necrosis factor alpha (TNF-α)-TNF-α receptor (TNFR) interaction plays a central role in the pathogenesis of various autoimmune diseases, particularly rheumatoid arthritis, and is therefore considered a key target for drug discovery. However, natural compounds that can specifically block the TNF-α-TNFR interaction are rarely reported. (-)-Epigallocatechin-3-gallate (EGCG) is the most active, abundant, and thoroughly investigated polyphenolic compound in green tea. However, the molecular mechanism by which EGCG ameliorates autoimmune arthritis remains to be elucidated. In the present study, we found that EGCG can directly bind to TNF-α, TNFR1, and TNFR2 with similar µM affinity and disrupt the interactions between TNF-α and TNFR1 and TNFR2, which inhibits TNF-α-induced L929 cell death, blocks TNF-α-induced NF-κB activation in 293-TNF-α response cell line, and eventually leads to inhibition of TNF-α-induced NF-κB signaling pathway in HFLS and MH7A cells. Thus, regular consumption of EGCG in green tea may represent a potential therapeutic agent for the treatment of TNF-α-associated diseases.