Flavonoid Synthesis Pathway Response to Low-Temperature Stress in a Desert Medicinal Plant, Agriophyllum Squarrosum (Sandrice).

Background/Objectives:Agriophyllum squarrosum (L.) Moq. (A. squarrosum), also known as sandrice, is an important medicinal plant widely distributed in dunes across all the deserts of China. Common garden trials have shown content variations in flavonoids among the ecotypes of sandrice, which correlated with temperature heterogeneity in situ. However, there have not been any environmental control experiments to further elucidate whether the accumulation of flavonoids was triggered by cold stress; Methods: This study conducted a four-day ambient 4 °C low-temperature treatment on three ecotypes along with an in situ annual mean temperature gradient (Dulan (DL), Aerxiang (AEX), and Dengkou (DK)); Results: Target metabolomics showed that 12 out of 14 flavonoids in sandrice were driven by cold stress. Among them, several flavonoids were significantly up-regulated, such as naringenin and naringenin chalcone in all three ecotypes; isorhamnetin, quercetin, dihydroquercetin, and kaempferol in DL and AEX; and astragalin in DK. They were accompanied by 19 structural genes of flavonoid synthesis and 33 transcription factors were markedly triggered by cold stress in sandrice. The upstream genes, AsqAEX006535-CHS, AsqAEX016074-C4H, and AsqAEX004011-4CL, were highly correlated with the enrichment of naringenin, which could be fine-tuned by AsqAEX015868-bHLH62, AsqAEX001711-MYB12, and AsqAEX002220-MYB1R1; Conclusions: This study sheds light on how desert plants like sandrice adapt to cold stress by relying on a unique flavonoid biosynthesis mechanism that regulating the accumulation of naringenin. It also supports the precise development of sandrice for the medicinal industry. Specifically, quercetin and isorhamnetin should be targeted for development in DL and AEX, while astragalin should be precisely developed in DK.

A phase II clinical trial of toripalimab in advanced solid tumors with polymerase epsilon/polymerase delta (POLE/POLD1) mutation.

Patients carrying mutations in polymerase epsilon/polymerase delta have shown positive responses to immune checkpoint inhibitors. Yet, prospective trials exploring the efficacy in those with polymerase epsilon/polymerase delta mutations are still lacking. A phase II clinical trial was initiated to evaluate the efficacy of toripalimab, a humanized IgG4K monoclonal antibody to human PD-1, in patients with advanced solid tumors with unselected polymerase epsilon/polymerase delta mutations but without microsatellite instability-high. A total of 15 patients were enrolled, 14 of whom were assessed for treatment efficacy. There was a 21.4% overall response rate, with a disease control rate of 57.1%. The median overall survival and median progression-free survival were 17.9 (95% CI 13.5-not reach) months and 2.5 (95% CI 1.4-not reach) months, respectively. For patients with exonuclease domain mutations, the objective response rate was 66.7% (2/3), with a disease control rate of 66.7% (2/3). For those with non-exonuclease domain mutations, the rates were 9.1% (1/11) and 54.5% (6/11), respectively. Notably, patients with PBRM1 gene mutations exhibited a high response rate to toripalimab at 75.0% (3/4). This study showed that neither the exonuclease domain mutations nor non-exonuclease domain mutations could fully predict the efficacy of immunotherapy, urging the need for more investigations to clarify potential immune sensitization differences within polymerase epsilon/polymerase delta mutation variants.

Role of hydrogen sulfide-microRNA crosstalk in health and disease.

The mutual regulation between hydrogen sulfide (H2S) and microRNA (miRNA) is involved in the development of many diseases, including cancer, cardiovascular disease, inflammatory disease, and high-risk pregnancy. Abnormal expressions of endogenous H2S-producing enzyme and miRNA in tissues and cells often indicate the occurrence of diseases, so the maintenance of their normal levels in the body can mitigate damages caused by various factors. Many studies have found that H2S can promote the migration, invasion, and proliferation of cancer cells by regulating the expression of miRNA, while many H2S donors can inhibit cancer progression by interfering with the proliferation, apoptosis, cell cycle, metastasis, and angiogenesis of cancer cells. Furthermore, the mutual regulation between H2S and miRNA can also prevent cell injury in cardiovascular disease and inflammatory disease through anti-inflammation, anti-oxidation, anti-apoptosis, and pro-autophagy. In addition, H2S can promote angiogenesis and relieve vasoconstriction by regulating the expression of miRNA, thereby improving fetal growth in high-risk pregnancy. In this review, we discuss the mechanism of mutual regulation between H2S and miRNA in various diseases, which may provide reliable therapeutic targets for these diseases.

Adaptative responses of Neurospora crassa by histidine kinases upon the attack of the arthropod Sinella curviseta.

Histidine kinases (HKs) are important sensor proteins in fungi and play an essential role in environmental adaptation. However, the mechanisms by which fungi sense and respond to fungivores attack via HKs are not fully understood. In this study, we utilized Neurospora crassa to investigate the involvement of HKs in responding to fungivores attack. We found that the 11 HKs in N. crassa not only affected the growth and development, but also led to fluctuations in antioxidant production. Ten mutants in the genes encoding HKs (except ∆phy1) showed increased production of reactive oxygen species (ROS), especially upon Sinella curviseta attack. The ROS burst triggered changes in conidia and perithecial beaks formation, as well as accumulation of ß-glucan, ergothioneine, ergosterol, and carotenoids. ß-glucan was increased in ∆hk9, ∆os1, ∆hcp1, ∆nik2, ∆sln1, ∆phy1 and ∆phy2 mutants compared to the wild-type strain. In parallel, ergothioneine accumulation was improved in ∆phy1 and ∆hk16 mutants and further increased upon attack, except in ∆os1 and ∆hk16 mutants. Additionally, fungivores attack stimulated ergosterol and dehydroergosterol production in ∆hk9 and ∆os1 mutants. Furthermore, deletion of these genes altered carotenoid accumulation, with wild-type strain, ∆hk9, ∆os1, ∆hcp1, ∆sln1, ∆phy2, and ∆dcc1mutants showing an increase in carotenoids upon attack. Taken together, HKs are involved in regulating the production of conidia and antioxidants. Thus, HKs may act as sensors of fungivores attack and effectively improve the adaptive capacity of fungi to environmental stimuli.

New Meroterpenes from South China Sea Soft Coral Litophyton brassicum.

A chemical investigation of the extracts from the soft coral Litophyton brassicum led to the isolation and identification of four new meroterpenes, brassihydroxybenzoquinone A and B (1 and 2) and brassinaphthoquinone A and B (3 and 4), along with two known related meroterpenes (5 and 6). Their structures were elucidated using high-resolution electrospray ionization mass spectrometry (HRESIMS), nuclear magnetic resonance (NMR) spectroscopy, and a comparison with the literature data. All compounds were evaluated for antibacterial activity against six pathogenic bacterial strains and for cytotoxic activity against three cancer cell lines. In the cytotoxic assay, all compounds were inactive at 10 µM against the A549, HeLa, and MDA-MB-231 cell lines. In the antibacterial assay, compounds 1 and 2 exhibited moderate inhibitory activity with minimum inhibitory concentrations (MIC) ranging from 8 to 64 µg/mL.

Correlative analysis of transcriptome and 16S rDNA in Procambarus clarkii reveals key signaling pathways are involved in Chlorantraniliprole stress response by phosphoinositide 3-kinase (PI3K).

Chlorantraniliprole (CAP), a diamide insecticide, is extensively used in agricultural production. With the increasing adoption of the rice-crayfish integrated farming model, pesticide application has become more frequent. However, the potential risk of CAP to crayfish (Procambarus clarkii) remains unclear. In this study, crayfish were exposed to 30, 60, 90 mg/L CAP for 96 h. As CAP exposure time and concentration increased, crayfish survival rates and total hemocyte counts (THC) decreased. Biochemical indicators revealed that CAP exposure induced oxidative stress and immunosuppression in crayfish, leading to metabolic disorders and reduced ATP content. Additionally, pathological analysis and 16S rDNA sequencing demonstrated that CAP exposure compromised the intestinal barrier of crayfish, altered the intestinal microbial community structure, and caused apoptosis. Differential gene expression analysis showed that CAP exposure significantly suppressed the expression of genes related to immune and energy metabolism pathways, resulting in immune dysfunction and insufficient energy supply, while activating the PI3K/AKT/mTOR signaling pathway. PI3K knockdown reduced antioxidant and digestive activities, increased the expression of proinflammatory and apoptosis genes, and exacerbated CAP-induced intestinal toxicity. This study is the first to explore the characterization and function of PI3K in crustaceans, providing new insights for further research on crustacean antioxidants and defense mechanisms.

Roseobacter weihaiensis sp. nov., a cellulose-degrading bacterium isolated from intestinal content of Nipponacmea schrenckii collected from golden beach in Weihai, China.

A Gram-staining-negative, dark pink, rod-shaped, amastigote and cellulose-degrading strain, designated H9T, was isolated from intestinal contents of Nipponacmea schrenckii. The isolate was able to grow at 4-42 °C (optimum, 25 °C), at pH 6.5-9.0 (optimum, pH 7.0), and with 0.0-11.0% (w/v) NaCl (optimum, 3.0-5.0%). Phylogenetic analysis of the 16S rRNA gene sequence suggested that isolate H9T belongs to the genus Roseobacter, neighboring Roseobacter insulae YSTF-M11T, Roseobacter cerasinus AI77T and Roseobacter ponti MM-7 T, and the pairwise sequence showed the highest similarity of 99.1% to Roseobacter insulae YSTF-M11T. The major fatty acid was summed feature 8 (C18:1ω7c and/or C18:1ω6c; 81.08%). The predominant respiratory quinone was Q-10. The polar lipids consisted of phosphatidylcholine, phosphatidylglycerol, an unknown lipid, and a small amount of an unknown phospholipid. The genome of strain H9T was 5,351,685 bp in length, and the DNA G + C content was 59.8%. The average amino acid identity (AAI), average nucleotide identity (ANI), and digital DNA hybridization (dDDH) values between strain H9T and closely related strains were 63.4-76.8%, 74.7-78.8%, and 13.4-19.7%, respectively. On the basis of the phenotypic, chemical taxonomic, and phylogenetic data, it is suggested that strain H9T should represent a novel species in the genus Roseobacter, for which the name Roseobacter weihaiensis sp. nov. is proposed. The type strain is H9T (= KCTC 82507 T = MCCC 1K04354T).

Seed coating with biocontrol bacteria encapsulated in sporopollenin exine capsules for the control of soil-borne plant diseases.

Coating seeds with biocontrol agents represents an effective approach for managing soil-borne plant diseases. However, improving the viability of biocontrol microorganisms on the seed surface or in the rhizosphere remains a big challenge due to biotic and abiotic stresses. In this work, we developed a microbial seed coating strategy that uses sporopollenin exine capsules (SECs) as carriers for the encapsulation of the biofilm-like biocontrol bacteria. SECs was extracted from camellia bee pollen, and then characterized by Fourier Transform infrared spectroscopy (FTIR), elemental analysis and thermal gravity analysis (TG). The Paenibacillus polymyxa ZF129, a biocontrol bacterium, was introduced into SECs using the vacuum-incubation method and characterized by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). Notably, the ZF129 cell formed a biofilm-like structure inside the SECs, which enhanced their tolerance to acidic stress. As a proof of concept, we applied ZF129-loaded SECs to coat pak choi seeds using a straightforward plate-shaking technique. The coated seeds demonstrated a high control efficacy of up to 60.46 % against clubroot disease. Overall, this study sheds light on the application of SECs as promising carrier for the encapsulation of biofilm-like biocontrol bacteria, further augmenting the biocontrol functionality of microbial seed coating.

Retinal ischemia-reperfusion injury and pretreatment with Lycium barbarum glycopeptide.

AIM: To investigate the antioxidant protective effect of Lycium barbarum glycopeptide (LbGP) pretreatment on retinal ischemia-reperfusion (I/R) injury (RIRI) in rats. METHODS: RIRI was induced in Sprague Dawley rats through anterior chamber perfusion, and pretreatment involved administering LbGP via gavage for 7d. After 24h of reperfusion, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatinine (CREA) levels, retinal structure, expression of Caspase-3 and Caspase-8, superoxide dismutase (SOD) activity, and malondialdehyde (MDA) in the retina were measured. RESULTS: The pretreatment with LbGP effectively protected the retina and retinal tissue from edema and inflammation in the ganglion cell layer (GCL) and nerve fiber layer (NFL) of rats subjected to RIRI, as shown by light microscopy and optical coherence tomography (OCT). Serum AST was higher in the model group than in the blank group (P=0.042), but no difference was found in ALT, AST, and CREA across the LbGP groups and model group. Caspase-3 expression was higher in the model group than in the blank group (P=0.006), but no difference was found among LbGP groups and the model group. Caspase-8 expression was higher in the model group than in the blank group (P=0.000), and lower in the 400 mg/kg LbGP group than in the model group (P=0.016). SOD activity was lower in the model group than in the blank group (P=0.001), and the decrease was slower in the 400 mg/kg LbGP group than in the model group (P=0.003). MDA content was higher in the model group than in the blank group (P=0.001), and lower in the 400 mg/kg LbGP group than in the model group (P=0.016). The pretreatment with LbGP did not result in any observed liver or renal toxicity in the model. CONCLUSION: LbGP pretreatment exhibits dose-dependent anti-inflammatory, and antioxidative effects by reducing Caspase-8 expression, preventing declines of SOD activity, and decreasing MDA content in the RIRI rat model.

Transcriptome analysis provides new insight into the mechanism of Bombyx mori under zinc exposure.

Zinc is a significant source of heavy metal pollution that poses risks to both human health and biodiversity. Excessive concentrations of zinc can hinder the growth and development of insects and trigger cell death through oxidative damage. The midgut is the main organ affected by exposure to heavy metals. The silkworm, a prominent insect species belonging to the Lepidoptera class and widely used in China, serves as a model for studying the genetic response to heavy metal stress. In this study, high-throughput sequencing technology was employed to investigate detoxification-related genes in the midgut that are induced by zinc exposure. A total of 11,320 unigenes and 14,723 transcripts were identified, with 553 differentially expressed genes (DEGs) detected, among which 394 were up-regulated and 159 were down-regulated. The Gene Ontology (GO) analysis revealed that 452 DEGs were involved in 18 biological process subclasses, 14 cellular component subclasses and 8 molecular functional subclasses. Furthermore, the KEGG analysis demonstrated enrichment in pathways such as Protein digestion, absorption and Lysosome. Validation of the expression levels of 9 detoxification-related DEGs through qRT-PCR confirmed the accuracy of the RNA-seq results. This study not only contributes new insights into the detoxification mechanisms mechanism of silkworms against zinc contamination, but also serves as a foundation basis for understanding the molecular detoxification processes in lepidopteran insects.

Phylogeographic analysis reveals multiple origins of the desert shrub Reaumuria songarica in northern Xinjiang, involving homoploid and tetraploid hybrids.

Hybrid speciation plays an important role in species diversification. The establishment of reproductive isolation is crucial for hybrid speciation, and the identification of diverse types of hybrids, particularly homoploid hybrid species, contributes to a comprehensive understanding of this process. Reaumuria songarica is a constructive shrub widespread in arid Central Asia. Previous studies have inferred that the R. songarica populations in the Gurbantunggut Desert (GuD) originated from homoploid hybridizations between its eastern and western lineages and may have evolved into an incipient species. To further elucidate the genetic composition of different hybrid populations and to determine the species boundary of this hybrid lineage, we investigated the overall phylogeographic structure of R. songarica based on variation patterns of five cpDNA and one nrITS sequences across 32 populations. Phylogenetic analyses demonstrated that within the GuD lineage, the Wuerhe population evolved directly from ancestral lineages, whereas the others originated from hybridizations between the eastern and western lineages. PCoA and genetic barrier analysis supported the subdivision of the GuD lineage into the southern (GuD-S) and northern (GuD-N) groups. Populations in the GuD-S group had a consistent genetic composition and the same ancestral female parent, indicating that they belonged to a homoploid hybrid lineage. However, the GuD-N group experienced genetic admixture of the eastern and western lineages on nrITS and cpDNA, with some populations inferred to be allopolyploid based on ploidy data. Based on cpDNA haplotypes, BEAST analyses showed that the GuD-S and GuD-N groups originated after 0.5 Ma. Our results suggest that multiple expansions and contractions of GuD, driven by Quaternary climatic oscillations and the Kunlun-Yellow River tectonic movement, are important causes of the complex origins of R. songarica populations in northern Xinjiang. This study highlights the complex origins of the Junggar Basin flora and the underappreciated role of hybridization in increasing its species diversity.

Emerging roles of hydrogen sulfide in colorectal cancer.

Hydrogen sulfide (H2S), an endogenous gasotransmitter, plays a key role in several critical physiological and pathological processes in vivo, including vasodilation, anti-infection, anti-tumor, anti-inflammation, and angiogenesis. In colorectal cancer (CRC), aberrant overexpression of H2S-producing enzymes has been observed. Due to the important role of H2S in the proliferation, growth, and death of cancer cells, H2S can serve as a potential target for cancer therapy. In this review, we thoroughly analyzed the underlying mechanism of action of H2S in CRC from the following aspects: the synthesis and catabolism of H2S in CRC cells and its effect on cell signal transduction pathways; the inhibition effects of exogenous H2S donors with different concentrations on the growth of CRC cells and the underlying mechanism of H2S in garlic and other natural products. Furthermore, we elucidate the expression characteristics of H2S in CRC and construct a comprehensive H2S-related signaling pathway network, which has important basic and practical significance for promoting the clinical research of H2S-related drugs.

Coating seeds with biocontrol bacteria-loaded sodium alginate/pectin hydrogel enhances the survival of bacteria and control efficacy against soil-borne vegetable diseases.

Microbial seed coatings serve as effective, labor-saving, and ecofriendly means of controlling soil-borne plant diseases. However, the survival of microbial agents on seed surfaces and in the rhizosphere remains a crucial challenge. In this work, we embedded a biocontrol bacteria (Bacillus subtilis ZF71) in sodium alginate (SA)/pectin (PC) hydrogel as a seed coating agent to control Fusarium root rot in cucumber. The formula of SA/PC hydrogel was optimized with the highest coating uniformity of 90 % in cucumber seeds. SA/PC hydrogel was characterized using rheological, gel content, and water content tests, thermal gravimetric analysis, and Fourier transform infrared spectroscopy. Bacillus subtilis ZF71 within the SA/PC hydrogel network formed a biofilm-like structure with a high viable cell content (8.30 log CFU/seed). After 37 days of storage, there was still a high number of Bacillus subtilis ZF71 cells (7.23 log CFU/seed) surviving on the surface of cucumber seeds. Pot experiments revealed a higher control efficiency against Fusarium root rot in ZF71-SA/PC cucumber seeds (53.26 %) compared with roots irrigated with a ZF71 suspension. Overall, this study introduced a promising microbial seed coating strategy based on biofilm formation that improved performance against soil-borne plant diseases.

Hydrogen Sulfide in Musculoskeletal Diseases: Molecular Mechanisms and Therapeutic Opportunities.

SIGNIFICANCE: Musculoskeletal diseases seriously affect global health, but their importance is greatly underestimated. These diseases often afflict the elderly, leading to disability, paralysis, and other complications. Hydrogen sulfide (H2S) plays an important role in the occurrence and development of musculoskeletal diseases, which may have potential ther-apeutic significance for these diseases. RECENT ADVANCES: Recently, it has been found that many musculoskeletal diseases, such as osteoporosis, periodontitis, muscle atrophy, muscle ischemia-reperfusion injury, mus-cle contraction under high fever, arthritis, and disc herniation, can be alleviated by sup-plementing H2S. H2S may be conducive to the development of multiple myeloma. The mechanism of H2S effect on the musculoskeletal system has been elucidated. A variety of H2S donors and nano-delivery systems provide prospects for H2S-based therapies. CRITICAL ISSUES: Related research remains at the level of cell or animal experiments, and clinical research is lacking. The role of H2S in more musculoskeletal disorders remains largely unknown. The importance of musculoskeletal diseases has not been widely con-cerned. Targeted delivery of H2S remains a challenging task. FUTURE DIRECTION: Develop therapeutic drugs for musculoskeletal diseases based on H2S and test their safety, efficacy, and tolerance. Explore the combination of current musculo-skeletal disease drugs with H2S releasing components to improve efficacy and avoid side effects. Carry out relevant clinical trials to verify the possibility of its widespread use.

Disulfide-stabilized trimeric hemagglutinin ectodomains provide enhanced heterologous influenza protection.

Influenza virus infection poses a continual menace to public health. Here, we developed soluble trimeric HA ectodomain vaccines by establishing interprotomer disulfide bonds in the stem region, which effectively preserve the native antigenicity of stem epitopes. The stable trimeric H1 ectodomain proteins exhibited higher thermal stabilities in comparison with unmodified HAs and showed strong binding activities towards a panel of anti-stem cross-reactive antibodies that recognize either interprotomer or intraprotomer epitopes. Negative stain transmission electron microscopy (TEM) analysis revealed the stable trimer architecture of the interprotomer disulfide-stapled WA11#5, NC99#2, and FLD#1 proteins as well as the irregular aggregation of unmodified HA molecules. Immunizations of mice with those trimeric HA ectodomain vaccines formulated with incomplete Freund's adjuvant elicited significantly more potent cross-neutralizing antibody responses and offered broader immuno-protection against lethal infections with heterologous influenza strains compared to unmodified HA proteins. Additionally, the findings of our study indicate that elevated levels of HA stem-specific antibody responses correlate with strengthened cross-protections. Our design strategy has proven effective in trimerizing HA ectodomains derived from both influenza A and B viruses, thereby providing a valuable reference for designing future influenza HA immunogens.

Green fabrication of modified lignin/zeolite/chitosan-based composite membranes for preservation of perishable foods.

Chitosan, as a kind of naturally occurring green and degradable material for the preservation of perishable foods, was investigated in this study with the objective of enhancing its preservation performances. Herein, lignin was modified using the solvent fractionation method (modified lignin, ML, including ML1-ML3), while natural clinoptilolite zeolite was modified using the alkali modification method (modified clinoptilolite zeolite, MCZ, including MCZ1-MCZ5). After optimizing the conditions, it was discovered that incorporating both ML3 and MCZ3 into pure chitosan-based membranes might be conducive to fabricate chitosan-based composite membranes for the preservation of perishable foods. As-prepared composite membranes possessed better visible light transmittance, antioxidant activity, and carbon dioxide/oxygen selectivity, resulting in improved preservation effects on the model perishable foods such as bananas, cherry tomatoes, and cheeses. These findings might indicate promising applications for chitosan-based composite membranes with modified lignin and zeolite in the field of eco-friendly degradable materials for the preservation of perishable foods.

Multi-omic characterization of air pollution effects: Applications of AirSigOmniTWP Hub.

Air pollution, particularly fine particulate matter and gaseous pollutants including NO2 and NOx, presents significant public health challenges. While the harmful effects of these pollutants are well-documented, the molecular mechanisms underlying their impact on health remain incompletely understood. In this study, we utilized genome-wide association study (GWAS) data from the UK Biobank, expression quantitative trait loci (eQTL) data from the Genotype-Tissue Expression (GTEx) project, and protein quantitative trait loci (pQTL) data from the Atherosclerosis Risk in Communities (ARIC) study to conduct comprehensive analyses using the Unified Test for Molecular Signatures (UTMOST), Transcriptome-wide Association Studies (TWAS), and Proteome-wide Association Studies (PWAS). To integrate and synthesize these analyses, we developed the AirSigOmniTWP Hub, a specialized platform designed to consolidate and interpret the results from UTMOST, TWAS, and PWAS. TWAS analysis identified a significant association between PM10 exposure and the gene INO80E in females (P = 4.37×10⁻5, FDR = 0.0383), suggesting a potential role in chromatin remodeling. PWAS analysis revealed a significant association between NOx exposure and the gene PIP in females (P = 2.28×10⁻5, FDR = 0.0299), implicating its involvement in inflammatory pathways. Additionally, UTMOST analyses uncovered significant associations between various pollutants and genes including NCOA4P3 and SPATS2L with PM2.5 exposure, indicating potential mechanisms related to transcriptional regulation and gene-environment interactions.

Reactivity of Atomic Oxygen Radical Anions in Metal Oxide Clusters.

Atomic oxygen radical anion (O•-) represents an important type of reactive centre that exists in both chemical and biological systems. Gas-phase atomic clusters can be studied under isolated and well controlled conditions. Studies of O•--containing clusters in the gas-phase provide a unique strategy to interpret the chemistry of O•- radicals at a strictly molecular level. This review summarizes the research progresses made since 2013 for the reactivity of O•- radicals in the atomically precise metal oxide clusters including negatively charged, nanosized, and neutral heteronuclear clusters benefitting from the development of advanced experimental techniques. New electronic and geometric factors to control the reactivity and product selectivity of O•- radicals under dark and photo-irradiation conditions have been revealed. The detailed mechanisms of O•- generation have been discussed for the reaction systems of nanosized and heteroatom-doped metal oxide clusters. The catalytic reactions mediated by the O•- radicals in metal clusters have also been successfully established and the microscopic mechanisms about the dynamic generation and depletion of O•- radicals have been clearly understood. The studies of O•- containing metal oxide clusters in the gas-phase provided new insights into the chemistry of reactive oxygen species in related condensed-phase systems.

Impact of different concentration iodinated contrast media on pain and comfort in abdominal computed tomography.

OBJECTIVES: To investigate whether high concentration iodinated contrast media (CM), compared with low concentration CM, could reduce pain and discomfort levels in patients who had level II and III venous conditions. METHODS: This prospective, single-center study enrolled patients who had level II and III venous conditions and underwent abdominal contrast-enhanced CT scan between July 2021 and February 2022. The venous condition to establish peripheral venous access for CM injection was graded using the Intravenous Access Scoring system, of which level II and III indicated poor venous condition and difficult venous access. Patients received iomeprol 400 in high concentration group and ioversol 320 in low group at an identical iodine delivery rate of 1.12 gI/s. The primary outcomes were pain and comfort levels. The secondary outcomes included adverse events and image quality. Patients rated pain intensity via Numerical Rating Scale and comfort level via Visual Analogue Scale with higher scores indicating higher levels of pain and discomfort. Quantitative and qualitative image assessment were compared between two groups. Continuous variables were compared using Student's t test or Mann-Whitney U test. Categorical variables were compared using χ2 test, χ2 test for trend or Fisher's exact test. RESULTS: A total of 206 patients (mean age, 60.13 ± 12.14 years; 81 males) were included with 99 in the high concentration group and 107 in the low concentration group. The high group had significantly lower pain scores (median 1 [IQR: 0-2] vs 2 (IQR 2-4), p < 0.001) and comfort scores (1 [IQR: 0-3] vs 3 [IQR: 2-5], p < 0.001) than the low group. Incidence of CM extravasation did not significantly differ (1.0 % vs 4.5 %, p = 0.214). No hypersensitivity reaction was observed. Qualitative assessment showed higher clarity scores of intrahepatic hepatic artery and portal vein in the high group. Quantitative assessment results were comparable between two groups. CONCLUSION: High concentration iodinated CM could lower pain intensity and improve comfort levels without comprising image quality of CT scan. High concentration CM is a preferable choice in patients with poor venous conditions during contrast-enhanced CT scan.

Dry Reforming of Methane to Syngas Mediated by Rhodium-Cobalt Oxide Cluster Anions Rh2CoO.

Dry reforming of methane (DRM) to syngas is an important route to co-convert CH4 and CO2. However, the highly endothermic nature of DRM induces the thermocatalysis to commonly operate at high temperatures that inevitably causes coke deposition through pyrolysis of methane. Herein, benefiting from the mass spectrometric experiments complemented with quantum chemical calculations, we have discovered that the bimetallic oxide cluster Rh2CoO- can mediate the co-conversion of CH4 and CO2 at room temperature giving rise to two free H2 molecules and two adsorbed CO molecules (COads). The only elementary step requiring the input of external energy (e.g., high temperature) is desorption of COads from the reaction intermediate Rh2CoOC2O2-. The doping effect of Co has also been clarified that the Co could tune the charge distribution and orbital energy of the active metal Rh, enabling the enhancement of cluster reactivity toward C-H activation, which is essential to facilitating the DRM to syngas. This work not only underlines the importance of temperature control over elementary steps in practical thermocatalysis but also identifies a promising active species containing the late 3d transition metal to drive DRM to syngas. The findings could provide novel insights into design of bimetallic catalysts for co-conversion of CH4 and CO2 at low temperatures.