Correction: Recent advances in the chemistry of isolable carbene analogues with group 13-15 elements.

Correction for 'Recent advances in the chemistry of isolable carbene analogues with group 13-15 elements' by Mian He et al., Chem. Soc. Rev., 2024, https://doi.org/10.1039/D3CS00784G.

The novel HLA-B*15:659 allele, identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

HLA-B*15:659 differs from HLA-B*15:02:01:01 by one nucleotide in exon 2.

Carbene-Stabilized Phosphagermylenylidene: A Heavier Analog of Isonitrile.

Phosphagermylenylidenes (R-P═Ge), as heavier analogs of isonitriles, whether in their free state or as complexes with a Lewis base, have not been previously identified as isolable entities. In this study, we report the synthesis of a stable monomeric phosphagermylenylidene within the coordination sphere of a Lewis base under ambient conditions. This species was synthesized by Lewis base-induced dedimerization of a cyclic phosphagermylenylidene dimer or via Me3SiCl elimination from a phosphinochlorogermylene framework. The deliberate integration of a bulky, electropositive N-heterocyclic boryl group at the phosphorus site, combined with coordination stabilization by a cyclic (alkyl)(amino)carbene at the low-valent germanium site, effectively mitigated its natural tendency toward oligomerization. Structural analyses and theoretical calculations have demonstrated that this unprecedented species features a P═Ge double bond, characterized by conventional electron-sharing π and σ bonds, complemented by lone pairs at both the phosphorus and germanium atoms. Preliminary reactivity studies show that this base-stabilized phosphagermylenylidene demonstrates facile release of ligands at the Ge atom, coordination to silver through the lone pair on P, and versatile reactivity including both (cyclo)addition and cleavage of the P═Ge double bond.

Recent advances in the chemistry of isolable carbene analogues with group 13-15 elements.

Carbenes (R2C:), compounds with a divalent carbon atom containing only six valence shell electrons, have evolved into a broader class with the replacement of the carbene carbon or the RC moiety with main group elements, leading to the creation of main group carbene analogues. These analogues, mirroring the electronic structure of carbenes (a lone pair of electrons and an empty orbital), demonstrate unique reactivity. Over the last three decades, this area has seen substantial advancements, paralleling the innovations in carbene chemistry. Recent studies have revealed a spectrum of unique carbene analogues, such as monocoordinate aluminylenes, nitrenes, and bismuthinidenes, notable for their extraordinary properties and diverse reactivity, offering promising applications in small molecule activation. This review delves into the isolable main group carbene analogues that are in the forefront from 2010 and beyond, spanning elements from group 13 (B, Al, Ga, In, and Tl), group 14 (Si, Ge, Sn, and Pb) and group 15 (N, P, As, Sb, and Bi). Specifically, this review focuses on the potential amphiphilic species that possess both lone pairs of electrons and vacant orbitals. We detail their comprehensive synthesis and stabilization strategies, outlining the reactivity arising from their distinct structural characteristics.

Toxicological evaluation and concentration of airborne PM0.1 in high air pollution period in Guangzhou, China.

The emissions and exposure limits for airborne PM0.1 are lacking, with limited scientific data for toxicity. Therefore, we continuously monitored and calculated the number and mass concentrations of airborne PM0.1 in December 2017, January 2018 and March 2018 during the high pollution period in Guangzhou. We collected PM0.1 from the same period and analyzed their chemical components. A549, THP-1 and A549/THP-1 co-cultured cells were selected for exposure to PM0.1, and evaluated for toxicological responses. Our aims are to 1) measure and analyze the number and mass concentrations, and chemical components of PM0.1; 2) evaluate and compare PM0.1 toxicity to different airway cells models at different time points. Guangzhou had the highest mass concentration of PM0.1 in December 2017, while the number concentration was the lowest. Chemical components in PM0.1 vary significantly at different time periods, and the correlation between the chemical composition or source of PM0.1 and the mass and number concentration of PM0.1 was dissimilar. Exposure to PM0.1 disrupted cell membranes, impaired mitochondrial function, promoted the expression of inflammatory mediators, and interfered with DNA replication in the cell cycle. The damage caused by exposure to PM0.1 at different times exhibited variations across different types of cells. PM0.1 in March 2018 stimulated co-cultured cells to secrete more inflammatory mediators, and CMA was significantly related to the expression of them. Our study indicates that it is essential to monitor both the mass and number concentrations of PM0.1 throughout all seasons annually, as conventional toxicological experiments and the internal components of PM0.1 may not effectively reveal the health damages caused by elevated number levels of PM0.1.

A stable rhodium-coordinated carbene with a σ0π2 electronic configuration.

Isolable singlet carbenes have universally adopted a σ2π0 electronic state, making them σ-donors and π-acceptors. We present a rhodium-coordinated, cationic cyclic diphosphinocarbene with a σ0π2 ground state configuration. Nuclear magnetic resonance spectroscopy studies show a carbene carbon chemical shift below -30.0 parts per million. X-ray crystallography reveals a planar RhP2C configuration. Quantum chemical calculations rationalize how σ-electron delocalization/donation and π-electron negative hyperconjugation together stabilize the formally vacant σ orbital and the filled π orbital at the carbene center. In contrast to traditional carbene counterparts this carbene can undergo synthetic transformations with both a Lewis base and a silver salt, producing a Lewis acid/base adduct and a silver π-complex, respectively. Exhibiting ambiphilic reactivity, it can also form a ketenimine through reaction with an isocyanide.

Genomic and phenotypic signatures provide insights into the wide adaptation of a global plant invader.

Invasive alien species are primary drivers of biodiversity loss and species extinction. Smooth cordgrass (Spartina alterniflora) is one of the most aggressive invasive plants in coastal ecosystems around the world. However, the genomic bases and evolutionary mechanisms underlying its invasion success have remained largely unknown. Here, we assembled a chromosome-level reference genome and performed phenotypic and population genomic analyses between native US and introduced Chinese populations. Our phenotypic comparisons showed that introduced Chinese populations have evolved competitive traits, such as early flowering time and greater plant biomass, during secondary introductions along China's coast. Population genomic and transcriptomic inferences revealed distinct evolutionary trajectories of low- and high-latitude Chinese populations. In particular, genetic mixture among different source populations, together with independent natural selection acting on distinct target genes, may have resulted in high genome dynamics of the introduced Chinese populations. Our study provides novel phenotypic and genomic evidence showing how smooth cordgrass rapidly adapts to variable environmental conditions in its introduced ranges. Moreover, candidate genes related to flowering time, fast growth, and stress tolerance (i.e., salinity and submergence) provide valuable genetic resources for future improvement of cereal crops.

Alkylation and Arylation at Boron in NHC-Stabilized Phosphaborenes.

Phosphaborenes, featuring a phosphorus-boron multiple bond, remain a relatively untapped area in chemical research due to the limited synthetic methods. Introducing leaving groups as substituents to the phosphorus or boron can pave the way for enhanced functionalization and modification. In this study, we present the synthesis of phosphaborenes featuring an N-heterocyclic boryl group on phosphorus and halogen substituent on boron, with stabilization provided by an N-heterocyclic carbene. Straightforward alkylation/arylation of these phosphaborenes is achieved by substituting the halogen with benzyl and aryl groups at the boron terminus. Our approach offers an efficient route to produce a diverse array of phosphaborene structures.

The performance of interferon gamma release assays in patients with nontuberculous mycobacterial infection: a systematic review and meta-analysis.

BACKGROUND: The actual positive rate of interferon gamma release assays (IGRAs) in patients with nontuberculous mycobacteria (NTM) infections remains unclear. This review and meta-analysis present the prevalence of positive IGRAs (T-SPOT.TB and QuantiFERON [QFT] tests) among patients infected with NTM isolates (with or without ESAT-6/CFP-10). METHODS: Several databases, including PubMed, Scopus, Embase, and Web of Science were searched (until June 18th, 2022). Studies that had the following data were included: (1) results of T-SPOT.TB, QuantiFERON (QFT) test, or both, (2) NTM species, and (3) NTM diseases, or NTM colonization. The metaprop command that incorporates a Freeman-Tukey double arcsine transformation is used for pooling proportions. RESULTS: A total of 11 articles (n = 929) were deemed eligible for inclusion. Meta-analysis identified that the overall pooled positive and indeterminate rates of IGRA results in patients with NTM infections was 16% and 5%, respectively. Subgroup analysis showed that the positive rate of IGRAs in patients infected with NTM (without ESAT-6/CFP-10) was 7% (95% CI, 1%-18%), and 44% (95%CI, 22%-68%) in patients infected with NTM (with ESAT-6/CFP-10). In addition, the indeterminate rate of QFT (7%, 95% CI: 4%-12%) was higher than that of T-SPOT.TB (0%; 95% CI, 0%-2%) among the overall population with NTM infections. CONCLUSIONS: The IGRAs have a moderate positive rate for the diagnosis of NTM (expressing ESAT-6/CFP-10) infections, and a significant indeterminate rate is observed among the overall population infected with NTM. However, these findings should be interpreted with caution because of the high heterogeneity among studies.

[Ferroptosis:Mechanism and Role in Malignant Tumors].

Ferroptosis is a new type of programmed cell death different from other cell death pathways such as apoptosis,autophagy,necrosis,and pyroptosis in terms of initiation,mechanisms,and molecular characteristics.As the accumulation of phospholipid hydroperoxides is the hallmark of ferroptosis,the balance between oxidative damage and antioxidant defense is critical to the regulatory mechanism of ferroptosis.In cancer,the upregulation of antioxidant defense pathways can inhibit ferroptosis,thereby promoting cancer cells to survive the oxidative stress and develop drug resistance.This review systematically introduces the main features and regulatory mechanisms of ferroptosis.In addition,we summarize the role of ferroptosis in the progression and drug resistance of malignant tumors,providing novel implications for further research on the pathogenesis of malignant tumors and discovery of new targets for anti-cancer therapy.

Evolutionary roles of polyploidization-derived structural variations in the phenotypic diversification of Panax species.

Genomic structural variations (SVs) are widespread in plant and animal genomes and play important roles in phenotypic novelty and species adaptation. Frequent whole genome duplications followed by (re)diploidizations have resulted in high diversity of genome architecture among extant species. In this study, we identified abundant genomic SVs in the Panax genus that are hypothesized to have occurred through during the repeated polyploidizations/(re)diploidizations. Our genome-wide comparisons demonstrated that although these polyploidization-derived SVs have evolved at distinct evolutionary stages, a large number of SV-intersecting genes showed enrichment in functionally important pathways related to secondary metabolites, photosynthesis and basic cellular activities. In line with these observations, our metabolic analyses of these Panax species revealed high diversity of primary and secondary metabolites both at the tissue and interspecific levels. In particular, genomic SVs identified at ginsenoside biosynthesis genes, including copy number variation and large fragment deletion, appear to have played important roles in the evolution and diversification of ginsenosides. A further herbivore deterrence experiment demonstrated that, as major triterpenoidal saponins found exclusively in Panax, ginsenosides provide protection against insect herbivores. Our study provides new insights on how polyploidization-derived SVs have contributed to phenotypic novelty and plant adaptation.

Post-hybridization introgression and natural selection promoted genomic divergence of Aegilops speltoides and the four S*-genome diploid species.

Understanding how different driving forces have promoted biological divergence and speciation is one of the central issues in evolutionary biology. The Triticum/Aegilops species complex contains 13 diploid species belonging to the A-, B- and D-lineages and offers an ideal system to address the evolutionary dynamics of lineage fusion and splitting. Here, we sequenced the whole genomes of one S-genome species (Aegilops speltoides) of the B-lineage and four S*-genome diploid species (Aegilops bicornis, Aegilops longissima, Aegilops sharonensis and Aegilops searsii) of the D-lineage at the population level. We performed detailed comparisons of the five species and with the other four representative A-, B- and D-lineage species. Our estimates identified frequent genetic introgressions from A- and B-lineages to the D-lineage species. A remarkable observation is the contrasting distributions of putative introgressed loci by the A- and B-lineages along all the seven chromosomes to the extant D-lineage species. These genetic introgressions resulted in high levels of genetic divergence at centromeric regions between Ae. speltoides (B-lineage) and the other four S*-genome diploid species (D-lineage), while natural selection is a potential contributor to divergence among the four S*-genome species at telomeric regions. Our study provides a genome-wide view on how genetic introgression and natural selection acted together yet chromosome-regionally divided to promote genomic divergence among the five S- and S*-genome diploid species, which provides new and nuanced insights into the evolutionary history of the Triticum/Aegilops species complex.

[Hydrochemical Characteristics and Control Factors of Groundwater in Shunping County, Hebei Province].

In order to study the chemical characteristics and ion source of groundwater and further serve the scientific development and management of water resources in Shunping County. A total of 33 groups of karst water and 12 groups of pore water samples were collected systematically in Shunping County, and the hydrochemical types, composition characteristics, and main controlling factors of various types of groundwater were analyzed by using Gibbs diagram, ion ratio relation, and multivariate statistical analysis methods, and the contribution rates of various sources to groundwater solutes were evaluated. The results showed that the pore water and karst water in the study area were weakly alkaline, with TDS ranging from 245.89 to 430.00 mg·L-1 and 223.54 to 1347.80 mg·L-1, respectively. The anion components of groundwater were mainly HCO3- and Ca2+. Groundwater in the study area could be grouped into PW1 and PW2 pore water and KW1, KW2, and KW3 karst water. PW1 and KW1 were HCO3-Ca·Mg type, PW2 was HCO3·Cl-Ca·Mg type, KW2 was HCO3·NO3-Ca·Mg type, and KW3 was SO4-Ca·Mg type with high salinity. The weathering of carbonate rock mainly composed of dolomite and silicate rock mainly composed of albiar and potassium feldspar were the main material sources of groundwater, and their contributions to each water body were 39.69% to 66.13% and 11.87% to 58.38%. Sewage discharge and fertilizer use in human activities had significant effects on KW2 groundwater and PW1, PW2, and KW1 groundwater, respectively. In addition, the contribution rate of atmospheric precipitation to each water body ranged from 1.09% to 7.94% on average.

[Hydrochemical Characteristics and Control Factors of Pore-water in the Middle and Upper Reaches of Muwen River].

In order to study the hydrochemical characteristics and ion sources of pore water in the middle and upper reaches of the Mouwen River, 29 groups of pore-water samples were collected in the Laiwu Basin. The main ion characteristics and their controlling factors of pore-water in this area were analyzed by using correlation and principal component analysis, Piper trigram, and Gibbs diagram methods. The main material sources of pore water in this area were revealed. The results showed that HCO3-, NO3-, SO42-, and Ca2+ were the main anions and cations in the pore water of the middle and upper reaches of the Mouwen River. With TDS >1000 mg·L-1 as the standard, the normal water chemistry type was mainly HCO3·NO3·SO4-Ca and HCO3·SO4-Ca·Mg, whereas the abnormal water chemistry type was mainly NO3·Cl-Ca. The chemical evolution of groundwater was mainly influenced by rock weathering, cation alternation adsorption, and human activities. Na++K+ mainly came from silicate weathering and dissolution, and HCO3-, Ca2+, and Mg2+ came from calcite weathering and dissolution involving carbonate and sulfuric acid. Alternation adsorption of cations and weathering of silicate rock provided a surplus of Ca2+ and Mg2+ for pore water. Industrial and mining activities such as domestic sewage mixing, agricultural planting activities, and iron and coal mining changed the chemical composition of pore water, especially NO3- exceeding the standard, which has become the main problem of the local groundwater chemical environment.

Stable Ketenyl Anions via Ligand Exchange at an Anionic Carbon as Powerful Synthons.

Under an atmosphere of carbon monoxide (CO), a (phosphino)diazomethyl anion salt [[P]-CN2 ][K(18-C-6)(THF)] (1) ([P]=[(CH2 )(NDipp)]2 P; 18-C-6=18-crown-6; Dipp=2,6-diisopropylphenyl) undergoes a facile N2 /CO exchange reaction giving the (phosphino)ketenyl anion salt [[P]-CCO][K(18-C-6)] (2). Oxidation of 2 with elemental Se affords the (selenophosphoryl)ketenyl anion salt [P](Se)-CCO][K(18-C-6)] (3). These ketenyl anions feature a strongly bent geometry at the P-bound carbon and this carbon atom is highly nucleophilic. The electronic structure of the ketenyl anion [[P]-CCO]- of 2 is examined by theoretical studies. Reactivity investigations demonstrate 2 as a versatile synthon for derivatives of ketene, enolate, acrylate and acrylimidate moieties.

Calcitriol Suppressed Isoproterenol-induced Proliferation of Cardiac Fibroblasts via Integrin ß3/FAK/Akt Pathway.

OBJECTIVE: Cardiac fibroblasts (CFs) proliferation and extracellular matrix deposition are important features of cardiac fibrosis. Various studies have indicated that vitamin D displays an anti-fibrotic property in chronic heart diseases. This study explored the role of vitamin D in the growth of CFs via an integrin signaling pathway. METHODS: MTT and 5-ethynyl-2'-deoxyuridine assays were performed to determine cell viability. Western blotting was performed to detect the expression of proliferating cell nuclear antigen (PCNA) and integrin signaling pathway. The fibronectin was observed by ELISA. Immunohistochemical staining was employed to evaluate the expression of integrin ß3. RESULTS: The PCNA expression in the CFs was enhanced after isoproterenol (ISO) stimulation accompanied by an elevated expression of integrin beta-3 (ß3). The blockade of the integrin ß3 with a specific integrin ß3 antibody reduced the PCNA expression induced by the ISO. Decreasing the integrin ß3 by siRNA reduced the ISO-triggered phosphorylation of FAK and Akt. Both the FAK inhibitor and Akt inhibitor suppressed the PCNA expression induced by the ISO in the CFs. Calcitriol (CAL), an active form of vitamin D, attenuated the ISO-induced CFs proliferation by downregulating the integrin ß3 expression, and phosphorylation of FAK and Akt. Moreover, CAL reduced the increased levels of fibronectin and hydroxyproline in the CFs culture medium triggered by the ISO. The administration of calcitriol decreased the integrin ß3 expression in the ISO-induced myocardial injury model. CONCLUSION: These findings revealed a novel role for CAL in suppressing the CFs growth by the downregulation of the integrin ß3/FAK/Akt pathway.

Sources, chemical components, and toxicological responses of size segregated urban air PM samples in high air pollution season in Guangzhou, China.

The sources, sizes, components, and toxicological responses of particulate matter (PM) have demonstrated remarkable spatiotemporal variability. However, associations between components, sources, and toxicological effects in different-sized PM remain unclear. The purposes of this study were to 1) determine the sources of PM chemical components, 2) investigate the associations between components and toxicology of PM from Guangzhou high air pollution season. We collected size-segregated PM samples (PM10-2.5, PM2.5-1, PM1-0.2, PM0.2) from December 2017 to March 2018 in Guangzhou. PM sources and components were analyzed. RAW264.7 mouse macrophages were treated with PM samples for 24 h followed by measurements of toxicological responses. The concentrations of PM10-2.5 and PM1-0.2 were relatively high in all samples. Water-soluble ions and PAHs were more abundant in smaller-diameter PM, while metallic elements were more enriched in larger-diameter PM. Traffic exhaust, soil dust, and biomass burning/petrochemical were the most important sources of PAHs, metals and ions, respectively. The main contributions to PM were soil dust, coal combustion, and biomass burning/petrochemical. Exposure to PM10-2.5 induced the most significant reduction of cell mitochondrial activity, oxidative stress and inflammatory response, whereas DNA damage, an increase of Sub G1/G0 population, and impaired cell membrane integrity were most evident with PM1-0.2 exposure. There were moderate or strong correlations between most single chemicals and almost all toxicological endpoints as well as between various toxicological outcomes. Our findings highlight those various size-segregated PM-induced toxicological effects in cells, and identify chemical components and sources of PM that play the key role in adverse intracellular responses. Although fine and ultrafine PM have attracted much attention, the inflammatory damage caused by coarse PM cannot be ignored.

Phenotypic and transcriptomic responses of the shade-grown species Panax ginseng to variable light conditions.

BACKGROUND AND AIMS: Elucidating how plant species respond to variable light conditions is important to understand the ecological adaptation to heterogeneous natural habitats. Plant performance and its underlying gene regulatory network have been well documented in sun-grown plants. However, the phenotypic and molecular responses of shade-grown plants under variable light conditions have remained largely unclear. METHODS: We assessed the differences in phenotypic performance between Panax ginseng (shade-grown) and Arabidopsis thaliana (sun-grown) under sunlight, shade and deep-shade conditions. To further address the molecular bases underpinning the phenotypic responses, we compared time-course transcriptomic expression profiling and candidate gene structures between the two species. KEY RESULTS: Our results show that, compared with arabidopsis, ginseng plants not only possess a lower degree of phenotypic plasticity among the three light conditions, but also exhibit higher photosynthetic efficiency under shade and deep-shade conditions. Further comparisons of the gene expression and structure reveal that differential transcriptional regulation together with increased copy number of photosynthesis-related genes (e.g. electron transfer and carbon fixation) may improve the photosynthetic efficiency of ginseng plants under the two shade conditions. In contrast, the inactivation of phytochrome-interacting factors (i.e. absent and no upregulation of the PIF genes) are potentially associated with the observed low degree of phenotypic plasticity of ginseng plants under variable light conditions. CONCLUSIONS: Our study provides new insights into how shade-grown plants respond to variable light conditions. Candidate genes related to shade adaptation in ginseng provide valuable genetic resources for future molecular breeding of high-density planting crops.

Winter and spring variation in sources, chemical components and toxicological responses of urban air particulate matter samples in Guangzhou, China.

The sources and chemical components of urban air particles exhibit seasonal variations that may affect their hazardousness to human health. Our aims were to investigate winter and spring variation in particulate matter (PM) sources, components and toxicological responses of different PM size fractions from samples collected in Guangzhou, China. Four size-segregated PM samples (PM10-2.5, PM2.5-1, PM1-0.2, and PM0.2) were collected separately during winter (December 2017 and January 2018) and spring (March 2018). All PM samples were analyzed for chemical components and characterized by source. RAW 264.7 macrophages were exposed to four doses of PM samples for 24 h. Cytotoxicity, oxidation, cell cycle, genotoxicity and inflammatory parameters were tested. PM concentrations were higher in the winter samples and caused more severe cytotoxicity and oxidative damage than to PM in the spring samples. PM in winter and spring led to increases in cell cycle and genotoxicity. The trends of size-segregated PM components were consistent in winter and spring samples. Metallic elements and PAHs were found in the largest concentrations in winter PM, but ions were found in the largest concentrations in spring PM. metallic elements, PAHs and ions in size-segregated PM samples were associated with most toxicological endpoints. Soil dust and biomass burning were the main sources of PM in winter, whereas traffic exhaust and biomass burning was the main source with of spring PM. Our results suggest that the composition of PM samples from Guangzhou differed during winter and spring, which led to strong variations in toxicological responses. The results demonstrate the importance of examining a different particle sizes, compositions and sources across different seasons, for human risk assessment.

[Treatment of avulsion fracture of inferior pole of patella with improved angle of anchor and double pulley technique].

OBJECTIVE: To evaluate the angle of modified anchor nail placement and the curative effect of double pulley technology for the treatment of extreme avulsion fracture of lower patella. METHODS: From December 2015 to December 2018, a total of 22 patients(10 males and 12 females) with avulsion fracture of the inferior pole of patella were retrospectively analyzed. The average age was (44.00±15.24) years old(range, 19 to 70 years). All patients were treated with modified anchor angle and double pulley technique. The range of motion(ROM) and Bostman score system were used to evaluate the functional recovery of knee joint. RESULTS: All 22 cases were followed up with an average of (30.86±8.00) weeks (18 to 46 weeks). At the last follow-up, ROM of the affected knee was (130.82±4.69) °, and the contralateral knee was (133.23 ± 3.15) °, there was no significant difference between two groups (P>0.05). The average Bostman score was (28.45±1.41) scores, 18 cases were excellent results, 4 cases were good. CONCLUSION: Improved anchor placement angle and double pulley technique for treatment of extreme avulsion fracture of lower patella is easy to operate, with satisfactory curative effect and good recovery of knee joint function.