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2.
Chem Soc Rev ; 2024 May 29.
Article in English | MEDLINE | ID: mdl-38808658

ABSTRACT

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.

3.
J Am Chem Soc ; 146(20): 14341-14348, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38726476

ABSTRACT

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.

4.
Cancer Cell ; 2024 May 23.
Article in English | MEDLINE | ID: mdl-38788718

ABSTRACT

Neuroendocrine carcinomas (NECs) are extremely lethal malignancies that can arise at almost any anatomic site. Characterization of NECs is hindered by their rarity and significant inter- and intra-tissue heterogeneity. Herein, through an integrative analysis of over 1,000 NECs originating from 31 various tissues, we reveal their tissue-independent convergence and further unveil molecular divergence driven by distinct transcriptional regulators. Pan-tissue NECs are therefore categorized into five intrinsic subtypes defined by ASCL1, NEUROD1, HNF4A, POU2F3, and YAP1. A comprehensive portrait of these subtypes is depicted, highlighting subtype-specific transcriptional programs, genomic alterations, evolution trajectories, therapeutic vulnerabilities, and clinicopathological presentations. Notably, the newly discovered HNF4A-dominated subtype-H exhibits a gastrointestinal-like signature, wild-type RB1, unique neuroendocrine differentiation, poor chemotherapeutic response, and prevalent large-cell morphology. The proposal of uniform classification paradigm illuminates transcriptional basis of NEC heterogeneity and bridges the gap across different lineages and cytomorphological variants, in which context-dependent prevalence of subtypes underlies their phenotypic disparities.

5.
Environ Sci Technol ; 2024 May 28.
Article in English | MEDLINE | ID: mdl-38804824

ABSTRACT

The relaxation of restrictions on Chinese Spring Festival (SF) firework displays in certain regions has raised concerns due to intensive emissions exacerbating air quality deterioration. To evaluate the impacts of fireworks on air quality, a comparative investigation was conducted in a city between 2022 (restricted fireworks) and 2023 SF (unrestricted), utilizing high time-resolution field observations of particle chemical components and air quality model simulations. We observed two severe PM2.5 pollution episodes primarily triggered by firework emissions and exacerbated by static meteorology (contributing approximately 30%) during 2023 SF, contrasting with its absence in 2022. During firework displays, freshly emitted particles containing more primary inorganics (such as chloride and metals like Al, Mg, and Ba), elemental carbon, and organic compounds (including polycyclic aromatic hydrocarbons) were predominant; subsequently, aged particles with more secondary components became prevalent and continued to worsen air quality. The primary emissions from fireworks constituted 54% of the observed high PM2.5 during the displays, contributing a peak hourly PM2.5 concentration of 188 µg/m3 and representing over 70% of the ambient PM2.5. This study underscores that caution should be exercised when igniting substantial fireworks under stable meteorological conditions, considering both the primary and potential secondary effects.

6.
Front Pharmacol ; 15: 1359832, 2024.
Article in English | MEDLINE | ID: mdl-38650628

ABSTRACT

Background: Acute myeloid leukemia (AML) is the most common form of leukemia among adults and is characterized by uncontrolled proliferation and clonal expansion of hematopoietic cells. There has been a significant improvement in the treatment of younger patients, however, prognosis in the elderly AML patients remains poor. Methods: We used computational methods and machine learning (ML) techniques to identify and explore the differential high-risk genes (DHRGs) in AML. The DHRGs were explored through multiple in silico approaches including genomic and functional analysis, survival analysis, immune infiltration, miRNA co-expression and stemness features analyses to reveal their prognostic importance in AML. Furthermore, using different ML algorithms, prognostic models were constructed and validated using the DHRGs. At the end molecular docking studies were performed to identify potential drug candidates targeting the selected DHRGs. Results: We identified a total of 80 DHRGs by comparing the differentially expressed genes derived between AML patients and normal controls and high-risk AML genes identified by Cox regression. Genetic and epigenetic alteration analyses of the DHRGs revealed a significant association of their copy number variations and methylation status with overall survival (OS) of AML patients. Out of the 137 models constructed using different ML algorithms, the combination of Ridge and plsRcox maintained the highest mean C-index and was used to build the final model. When AML patients were classified into low- and high-risk groups based on DHRGs, the low-risk group had significantly longer OS in the AML training and validation cohorts. Furthermore, immune infiltration, miRNA coexpression, stemness feature and hallmark pathway analyses revealed significant differences in the prognosis of the low- and high-risk AML groups. Drug sensitivity and molecular docking studies revealed top 5 drugs, including carboplatin and austocystin-D that may significantly affect the DHRGs in AML. Conclusion: The findings from the current study identified a set of high-risk genes that may be used as prognostic and therapeutic markers for AML patients. In addition, significant use of the ML algorithms in constructing and validating the prognostic models in AML was demonstrated. Although our study used extensive bioinformatics and machine learning methods to identify the hub genes in AML, their experimental validations using knock-out/-in methods would strengthen our findings.

7.
J Mech Behav Biomed Mater ; 155: 106553, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38640694

ABSTRACT

Developing a gradient porous scaffold similar to bone structure is gaining increasing attention in bone tissue engineering. The GelMA/HAP hydrogel has demonstrated potential in bone repair. Although 3D printing can build GelMA/HAP with porous structure, fabricating porous GelMA/HAP with gradient porosity and pore size in one step remains challenging. In this paper, a gradient porous structure with controllable pore size, based on gelatin methacryloyl (GelMA) and hydxroxyapatite (HAP), was engineered and printed using stereolithography. Firstly, the GelMA and HAP were mixed to prepare a hydrogel with a solid content ranging from 10 wt% to 50 wt% for stereolithography. Taking advantage of the sol-gel characteristics of GelMA/HAP hydrogel, GelMA/HAP was fed on the workbench through a combination of extrusion and paving to form a thin layer. During the curing of each layer, the hydrogel exposed to the curing of a single UV beam immediately solidified, forming a highly interconnected porous structure. Additionally, the hydrogel outside the scanning range could be further polymerized to form a relatively dense structure due to the residual laser energy. Finally, without gradient structural design or changing printing parameters, the gradient porous structure of bone-like could be printed in a single-step process. By adjusting the curing parameters of the single UV beam and the concentration and size of ceramic in the hydrogel, the printed pore diameter of the spongy structure could be controlled within the range of 50-260 µm, while the thickness of the compact area could be adjusted within 130-670 µm.


Subject(s)
Biocompatible Materials , Durapatite , Gelatin , Methacrylates , Printing, Three-Dimensional , Porosity , Gelatin/chemistry , Biocompatible Materials/chemistry , Durapatite/chemistry , Methacrylates/chemistry , Tissue Scaffolds/chemistry , Hydrogels/chemistry , Tissue Engineering
8.
Environ Res ; 251(Pt 1): 118569, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38431069

ABSTRACT

Topography of a place has a significant impact on soil characteristics that ultimately influence soil iodine levels. Lower Himalayan region (LHR) in Pakistan has a wide range of climatic and geological variations. Hence, an investigation was conducted to analyze the iodine concentration and other physicochemical properties of soils in two LHR districts, Haripur and Mansehra. Spatial analysis indicated a decrease in iodine levels in the mountainous regions in comparison to the flat portions of LHR. Soil samples obtained from different locations across Haripur had a stronger affinity for iodine due to variations in solubility and adsorption of iodine to soil clay components, which can be attributed to lower pH, higher organic matter, and a higher cation exchange capacity (CEC). In contrast to the plains of Haripur, elevated locations in the Mansehra district had decreased levels of iodine, along with a higher soil pH and reduced soil organic matter. The soil erosion and depletion of soil micronutrients in the hilly region of Mansehra may be attributed to the unfavorable soil conditions and excessive precipitation. Presence of clay, iron (Fe), and aluminum (Al) in the soil led to a rise in iodine levels. Iodine concentrations exhibited an inverse relationship with soil acidity. Study revealed a direct correlation between soil iodine levels and their cation exchange capacity (CEC) and clay content. This study aims to gather fundamental data for the chosen regions of LHR to address illnesses caused by iodine deficiency.


Subject(s)
Iodine , Soil , Soil/chemistry , Iodine/analysis , Iodine/chemistry , Pakistan , Hydrogen-Ion Concentration
9.
Chem Soc Rev ; 53(8): 3896-3951, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38436383

ABSTRACT

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.

10.
Environ Int ; 185: 108487, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38367554

ABSTRACT

Particulate organic nitrates (pONs) have drawn growing interests due to their effects on nitrogen cycling, air pollution, and regional climate. While secondary formation is typically considered as the major source of pONs, direct emissions from various sources remain poorly explored. Ship exhausts have been known as an important source of reactive nitrogen species, yet pONs emissions from ship have been rarely characterized. In this study, we conducted atmospheric measurement of pONs during a ship-based cruise measurement campaign in the East China Sea and also emission measurement of pONs from ship exhausts. During the ship-based cruise, total five typical kinds of pONs were determined and the average total concentrations of five pONs were 479 ± 193 and 250 ± 139 ng m-3 when sampling was influenced by ship emissions or not, respectively, indicating the notable impact of ship exhaust plumes on ambient pONs. Further, five typical pONs were successfully identified and quantified from ship exhausts, with the average total concentration of 1123 ± 406 µg m-3. The much higher pONs levels in ship exhausts than in ambient particulate matters demonstrated ship emission as an important source for pONs. Additionally, their emission factors from ship exhausts were determined as at a range of 0.1-12.6 mg kWh-1. The chemical transport model simulations indicate that direct pONs emissions from ship exert a significant contribution to atmospheric pONs, especially in the clean marine atmosphere. These findings provide compelling evidence for direct emission of pONs from ship and its considerable effects. We call for further studies to better characterize the direct pONs emissions from ship and other potential sources, which should be incorporated into global and regional models.


Subject(s)
Air Pollutants , Air Pollution , Air Pollutants/analysis , Ships , Environmental Monitoring , Particulate Matter/analysis , Air Pollution/analysis , Vehicle Emissions/analysis , Dust , Coal , China
11.
Front Oncol ; 14: 1338634, 2024.
Article in English | MEDLINE | ID: mdl-38333684

ABSTRACT

Background: Lung cancer is the leading cause of cancer deaths globally, with lung adenocarcinoma (LUAD) and squamous cell carcinoma (LUSC) being major subtypes. Immunotherapy has emerged as a promising approach for the treatment of lung cancer, but understanding the underlying mechanisms of immune dysregulation is crucial for the development of effective therapies. This study aimed to investigate the distinctive cellular features of LUAD and LUSC and identify potential biomarkers associated with the pathogenesis and clinical outcomes of each subtype. Methods: We used digital cytometry techniques to analyze the RNA-Seq data of 1128 lung cancer patients from The Cancer Genome Atlas (TCGA) database. The abundance of cell subtypes and ecotypes in LUAD and LUSC patients was quantified. Univariate survival analysis was used to investigate their associations with patient overall survival (OS). Differential gene expression analysis and gene co-expression network construction were carried out to explore the gene expression patterns of LUSC patients with distinct survival outcomes. Scratch wound-healing assay, colony formation assay, and transwell assay were used to validate the candidate drugs for LUSC treatment. Results: We found differential expression of cell subtypes between LUAD and LUSC, with certain cell subtypes being prognostic for survival in both subtypes. We also identified differential gene expression and gene co-expression modules associated with macrophages.3/PCs.2 ratio in LUSC patients with distinct survival outcomes. Furthermore, ecotype ratios were found to be prognostic in both subtypes and machine learning models showed that certain cell subtypes, such as epithelial.cells.1, epithelial.cells.5, and endothelial.cells.2 are important for predicting LUSC. Ginkgolide B and triamterene can inhibit the proliferation, invasion, and migration of LUSC cell lines. Conclusion: We provide insight into the distinctive cellular features of LUAD and LUSC, and identify potential biomarkers associated with the pathogenesis and clinical outcomes of each subtype. Ginkgolide B and triamterene could be promising drugs for LUSC treatment.

12.
Health Qual Life Outcomes ; 22(1): 23, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38413940

ABSTRACT

BACKGROUND: Multimorbidity, body pain, sleep disturbance, and depression are major clinical and public health challenges. This paper aimed to examine the associations of multimorbidity with body pain, sleep duration, and depression; and whether the associations varied by socioeconomic status. METHODS: Data was derived from four waves of the nationally representative China Health and Retirement Longitudinal Study (CHARLS), including participants aged 45 years and older in 2011. 12 physical non-communicable diseases and 1 mental chronic disease were used to measure multimorbidity. Educational attainment and annual per-capita household consumption expenditure were employed as proxies for socioeconomic status. RESULTS: Of the 16,931 participants aged 45 + years old, the proportion of people with multimorbidity was 37.87% at baseline. The number of multimorbidity increased with older age and higher socioeconomic status. Multimorbidity was associated with more body pain (incidence rate ratio (IRR) = 1.53, 95% CI = 1.45-1.61), and decreased sleep duration (ß = -0.26, 95% CI = -0.36--0.15). Furthermore, multimorbidity was associated with increased depression risks (odds ratio (OR) = 1.54, 95% CI = 1.44-1.64, adjusted for sociodemographic variables), with the mediating effects of the number of body pain and sleep duration. The associations between multimorbidity and depression persisted among different socioeconomic groups. CONCLUSIONS: Multimorbidity was associated with increased body pain, decreased sleep duration, and further led to increased depression risks. It is necessary to pay attention to the multimorbidity of middle-aged and older adults, relieve their body pain, guarantee sufficient sleep, so as to reduce depression risks.


Subject(s)
Depression , Multimorbidity , Middle Aged , Humans , Aged , Longitudinal Studies , Depression/epidemiology , Sleep Duration , Quality of Life , Pain/epidemiology , China/epidemiology
13.
J Ethnopharmacol ; 326: 117865, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38369066

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: 2,3,5,4'-tetrahydroxystilbene-2-O-ß-D-glucopyranoside (TSG) as the primary constituent of Polygonum multiflorum Thumb. (PM) possesses anti-oxidative, antihypercholesterolemic, anti-tumor and many more biological activities. The root of PM has been used as a tonic medicine for thousands of years. However, cases of PM-induced liver injury are occasionally reported, and considered to be related to the host immune status. AIM OF THE STUDY: The primary toxic elements and specific mechanisms PM causing liver damage are still not thoroughly clear. Our study aimed to investigate the influences of TSG on the immune response in idiosyncratic hepatotoxicity of PM. MATERIALS AND METHODS: The male C57BL/6 mice were treated with different doses of TSG and the alterations in liver histology, serum liver enzyme levels, proportions of T cells and cytokines secretion were evaluated by hematoxylin and eosin (HE), RNA sequencing, quantitative real time polymerase chain reaction (qRT-PCR), Flow cytometry (FCM), and enzyme-linked immunosorbent assay (ELISA), respectively. Then, primary spleen cells from drug-naive mice were isolated and cultured with TSG in vitro. T cell subsets proliferation and cytokines secretion after treated with TSG were assessed by CCK8, FCM and ELISA. In addition, mice were pre-treated with anti-CD25 for depleting regulatory T cells (Tregs), and then administered with TSG. Liver functions and immunological alterations were analyzed to evaluate liver injury. RESULTS: Data showed that TSG induced liver damage, and immune cells infiltration in the liver tissues. FCM results showed that TSG could activate CD4+T and CD8+T in the liver. Results further confirmed that TSG notably up-regulated the levels of inflammatory cytokines including TNF-α, IFN-γ, IL-18, perforin and granzyme B in the liver tissues. Furthermore, based on transcriptomics profiles, some immune system-related pathways including leukocyte activation involved in inflammatory response, leukocyte cell-cell adhesion, regulation of interleukin-1 beta production, mononuclear cell migration, antigen processing and presentation were altered in TSG treated mice. CD8+T/CD4+T cells were also stimulated by TSG in vitro. Interestingly, increased proportion of Tregs was observed after TSG treatment in vitro and in vivo. Foxp3 and TGF-ß1 mRNA expressions were up-regulated in the liver tissues. Depletion of Tregs moderately enhanced TSG induced the secretion of inflammatory cytokines in serum. CONCLUSIONS: Our findings showed that TSG could trigger CD4+T and CD8+T cells proliferation, promote cytokines secretion, which revealed that adaptive immune response associated with the mild liver injury cause by TSG administration. Regulatory T cells (Tregs) mainly sustain immunological tolerance, and in this study, the progression of TSG induced liver injury was limited by Tregs. The results of our investigations allow us to preliminarily understand the mechanisms of PM related idiosyncratic hepatotoxicity.


Subject(s)
Chemical and Drug Induced Liver Injury, Chronic , Fallopia multiflora , Polygonum , Stilbenes , Mice , Male , Animals , Chemical and Drug Induced Liver Injury, Chronic/drug therapy , Mice, Inbred C57BL , Cytokines/genetics , Immunity , Stilbenes/toxicity , Stilbenes/therapeutic use
14.
Sci Total Environ ; 921: 171224, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38402960

ABSTRACT

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.


Subject(s)
Air Pollutants , Air Pollution , Air Pollutants/analysis , Particulate Matter/toxicity , Particulate Matter/analysis , China , Inflammation Mediators , Particle Size , Environmental Monitoring
15.
Plant Commun ; 5(4): 100820, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38221758

ABSTRACT

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.


Subject(s)
Ecosystem , Plants , Poaceae/genetics , Genomics , Introduced Species
16.
Hum Genet ; 143(1): 49-58, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38180560

ABSTRACT

Observational studies have revealed that ischemic heart disease (IHD) has a unique manifestation on electrocardiographic (ECG). However, the genetic relationships between IHD and ECG remain unclear. We took 12-lead ECG as phenotypes to conduct genome-wide association studies (GWAS) for 41,960 samples from UK-Biobank (UKB). By leveraging large-scale GWAS summary of ECG and IHD (downloaded from FinnGen database), we performed LD score regression (LDSC), Mendelian randomization (MR), and polygenic risk score (PRS) regression to explore genetic relationships between IHD and ECG. Finally, we constructed an XGBoost model to predict IHD by integrating PRS and ECG. The GWAS identified 114 independent SNPs significantly (P value < 5 × 10-8/800, where 800 denotes the number of ECG features) associated with ECG. LDSC analysis indicated significant (P value < 0.05) genetic correlations between 39 ECG features and IHD. MR analysis performed by five approaches showed a putative causal effect of IHD on four S wave related ECG features at lead III. Integrating PRS for these ECG features with age and gender, the XGBoost model achieved Area Under Curve (AUC) 0.72 in predicting IHD. Here, we provide genetic evidence supporting S wave related ECG features at lead III to monitor the IHD risk, and open up a unique approach to integrate ECG with genetic factors for pre-warning IHD.


Subject(s)
Genome-Wide Association Study , Myocardial Ischemia , Humans , Mendelian Randomization Analysis/methods , Myocardial Ischemia/genetics , Polymorphism, Single Nucleotide , Phenotype , Genetic Risk Score
17.
Science ; 383(6678): 81-85, 2024 Jan 05.
Article in English | MEDLINE | ID: mdl-38175894

ABSTRACT

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.

18.
Environ Pollut ; 344: 123368, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38246217

ABSTRACT

Nitrophenols have received extensive attention due to their strong light-absorbing ability in the near-ultraviolet-visible region, which could be influenced by the atmospheric processes of nitrophenols. However, our knowledge and understanding of the formation and evolution of nitrophenols are still in the nascent stages. In the present study, the mixing states of four mononitrophenol particles (i.e., nitrophenol, methynitrophenol, nitrocatechol, and methoxynitrophenol), and one nitropolycyclic aromatic hydrocarbon particles (i.e., nitronaphthol (NN)) were investigated using a single-particle aerosol mass spectrometer (SPAMS) in November 2019 in Qingdao, China. The results showed, for the first time, that mononitrophenols and NN exhibit different mixing states and diurnal variations. Four mononitrophenols were internally mixed well with each other, and with organic acids, nitrates, potassium, and naphthalene. The diurnal variation in the number fraction of mononitrophenols presented two peaks at 07:00 to 09:00 and 18:00 to 20:00, and a valley at noon. Atmospheric environmental conditions, including NO2, O3, relative humidity, and temperature, can significantly influence the diurnal variation of mononitrophenols. Multiple linear regression and random forest regression models revealed that the main factors controlling the diurnal variation of mononitrophenols were photochemical reactions during the day and aqueous-phase reactions during the night. Unlike mononitrophenols, about 62-83% of NN were internally mixed with [NH4]+ and [H(NO3)2]-, but not with organic acids and potassium. The diurnal variation of NN was also different from that of mononitrophenols, generally increased from 17:00 to 10:00 and then rapidly decreaed from 11:00 to 16:00. These results imply that NN may have sources and atmospheric processes that are different from mononitrophenols. We speculate that this is mostly controlled by photochemical reactions and mixing with [NH4]+, which may influence the diurnal variation of NN in the ambient particles; however, this requires further confirmation. These findings extend our current understanding of the atmospheric formation and evolution of nitrophenols.


Subject(s)
Air Pollutants , Nitrophenols , Potassium , Circadian Rhythm , Antifungal Agents , China , Dust , Aerosols , Environmental Monitoring , Particulate Matter , Seasons
19.
Aging (Albany NY) ; 16(3): 2340-2361, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38277218

ABSTRACT

Acute myeloid leukemia (AML) is a highly heterogeneous malignant disease of the blood cell. The current therapies for AML are unsatisfactory and the molecular mechanisms underlying AML are unclear. 5-methylcytosine (m5C) is an important posttranscriptional modification of mRNA, and is involved in the regulation of mRNA stability, translation, and other aspects of RNA metabolism. However, based on our knowledge of published literature, the role of the m5C regulators has not been explored in AML till date. In this study, we clarified the expression and gene variants of m5C regulators in AML and found that most m5C regulators were differentially expressed and correlated with disease prognosis. We also found that the methylation status of certain m5C regulators (e.g., DNMT3A, DNMT3B) affects the survival of AML patients. Two m5C modification subtypes, and high- and low-risk subgroups identified based on the expression of m5C regulators showed significant differences in the prognosis as well as immune cell infiltration. In addition, most of the m5C regulators were found to be correlated with miRNA expression in AML, as well as IC50 values of many drugs. The miRNA and GSVA analysis were used to identify the different miRNAs and KEGG or hallmark pathways between high- and low-risk subgroups. We also built a prognostic model based on m5C regulators, which was validated by two GSE databases. To verify the reliability of our analysis and conclusions, qPCR was used to identify the expressions of m5C regulators between normal and AML. In summary, we comprehensively explored the molecular characteristics of m5C regulators and built a prognostic model in AML. We proposed new mechanistic insights into the role of m5C in multiple databases and clinical data, which may pave novel ways for the development of therapeutic strategies.


Subject(s)
Leukemia, Myeloid, Acute , MicroRNAs , Humans , RNA , 5-Methylcytosine , Reproducibility of Results , Leukemia, Myeloid, Acute/genetics , RNA, Messenger , Tumor Microenvironment/genetics
20.
Chem Asian J ; 19(1): e202300794, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-37937445

ABSTRACT

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.

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