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1.
Front Immunol ; 15: 1371662, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39221249

RESUMO

Background: The relationship between peripheral immune cells and immunoglobulin A nephropathy (IgAN) is widely known; however, causal evidence of this link is lacking. Here, we aimed to determine the causal effect of peripheral immune cells, specifically total white blood cells, lymphocytes, monocytes, basophils, eosinophils, and neutrophils, as well as lymphocyte subset traits, on the IgAN risk using a Mendelian randomization (MR) analysis. Methods: The inverse-variance weighted (IVW) method was used for the primary analysis. We applied three complementary methods, including the weighted median, MR-Egger regression, and MR-PRESSO, to detect and correct for the effect of horizontal pleiotropy. Additionally, we performed a multivariable MR (MVMR) analysis, adjusting for the effects of C-reactive protein (CRP) levels. The roles of specific lymphocyte subtypes and their significance have garnered interest. Bidirectional two-sample MR analysis was performed to test the potential causal relationships between immune traits, including median fluorescence intensities (MFIs) and the relative cell count (AC), and IgAN. Results: The IVW-MR analysis suggested a potential causal relationship between lymphocyte counts and IgAN in Europe (OR per 1-SD increase: 1.43, 95% CI: 1.08-1.88, P = 0.0123). The risk effect of lymphocytes remained even after adjusting for CRP levels using the MVMR method (OR per 1-SD increase: 1.44, 95% CI: 1.05-1.96, P = 0.0210). The other sensitivity analyses showed a consistent trend. The largest GWAS published to date was used for peripheral blood immunophenotyping to explore the potential causal relationship between peripheral immune cell subsets and IgAN. Six AC-IgAN and 14 MFI-IgAN pairs that reached statistical significance (P < 0.05) were detected. Notably, CD3, expressed in eight subsets of T cells, consistently showed a positive correlation with IgAN. The bidirectional MR analysis did not reveal any evidence of reverse causality. According to the sensitivity analysis, horizontal pleiotropy was unlikely to distort the causal estimates. Conclusions: Genetically determined high lymphocyte counts were associated with IgAN, supporting that high lymphocyte counts is causal risk factor for IgAN.


Assuntos
Glomerulonefrite por IGA , Análise da Randomização Mendeliana , Humanos , Glomerulonefrite por IGA/genética , Glomerulonefrite por IGA/imunologia , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único
2.
J Hazard Mater ; 479: 135607, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39208636

RESUMO

Size-resolved gas-particle partitioning of semi-volatile organic compounds (SVOCs) can affect their environmental behaviors and health effects, which has not been widely studied in comparing with the gas-total suspended particle partitioning. Herein, the size-resolved gas-particle partitioning quotient (KPi) of polycyclic aromatic hydrocarbons (PAHs) in a large temperature range (-20.6 â„ƒ ∼ 29.4 â„ƒ) was firstly comprehensively studied. The log KPi values of PAHs related to fine particles were significantly higher than those related to coarse particles. When the logarithm of subcooled liquid-vapor pressure (log PL0) ∈ [-7, -1), the regression slopes of log KPi vs log PL0 related to the particle size > 1.0 µm were shallower than those with the particle size range of 0.10-1.0 µm, which indicated the influence of particle size on KPi. Among the three previous prediction equations of gas-particle partitioning quotient, the empirical equation based on the ambient temperature matched better with the measured log KPi. Therefore, a new prediction equation including ambient temperature and particle size as the two major parameters was established. For most particle size ranges, the new equation showed better prediction performance than the three previous equations. In summary, this study provided new insights for the size-resolved gas-particle partitioning mechanism and quotient.

3.
Mult Scler Relat Disord ; 90: 105803, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39128164

RESUMO

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune-mediated primary inflammatory myelinopathy of the central nervous system that primarily affects the optic nerve and spinal cord. The aquaporin 4 antibody (AQP4-Ab) is a specific autoantibody marker for NMOSD. Most patients with NMOSD are seropositive for AQP4-Ab, thus aiding physicians in identifying ways to treat NMOSD. AQP4-Ab has been tested in many clinical and laboratory studies, demonstrating effectiveness in diagnosing NMOSD. Recently, novel assays have been developed for the rapid and accurate detection of AQP4-Ab, providing further guidance for the diagnosis and treatment of NMOSD. This article summarizes the importance of rapid and accurate diagnosis for treating NMOSD based on a review of the latest relevant literature. We discussed current challenges and methods for improvement to offer new ideas for exploring rapid and accurate AQP4-Ab detection methods, aiming for early diagnosis of NMOSD.

4.
Chemosphere ; 363: 142953, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39089337

RESUMO

In this study, we have utilized theoretical calculations to predict the reaction active sites of naproxen when reacting with radicals and to further study the thermodynamics and kinetics of the reactions with ·OH and SO4-·. The evidence, derived from the average local ionization energy and electrostatic potential, points to the naphthalene ring as the preferred site of attack, especially for the C2, C6, C9, and C10 sites. The changes in Gibbs free energy and enthalpy of the reactions initiated by ·OH and SO4-· ranged between -19.6 kcal/mol - 26.3 kcal/mol and -22.3 kcal/mol -18.5 kcal/mol, respectively. More in-depth investigation revealed that RA2 pathway for ·OH exhibited the lowest free energy of activation, suggesting this reaction is more inclined to proceed. The second-order rate constant results indicate the ·OH attacking reaction is faster than reactions initiated by SO4·-, yet controlled by diffusion. The consistency between theoretical findings and experimental data underscores the validity of this computational method for our study.


Assuntos
Radical Hidroxila , Naproxeno , Sulfatos , Termodinâmica , Naproxeno/química , Cinética , Radical Hidroxila/química , Sulfatos/química , Água/química , Modelos Químicos
5.
Nature ; 632(8027): 1032-1037, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39198671

RESUMO

Superconductivity in a highly correlated kagome system has been theoretically proposed for years (refs. 1-5), yet the experimental realization is hard to achieve6,7. The recently discovered vanadium-based kagome materials8, which exhibit both superconductivity9-11 and charge-density-wave orders12-14, are nonmagnetic8,9 and weakly correlated15,16. Thus these materials are unlikely to host the exotic superconductivity theoretically proposed. Here we report the discovery of a chromium-based kagome metal, CsCr3Sb5, which is contrastingly featured with strong electron correlations, frustrated magnetism and characteristic flat bands close to the Fermi level. Under ambient pressure, this kagome metal undergoes a concurrent structural and magnetic phase transition at 55 K, with a stripe-like 4a0 structural modulation. At high pressure, the phase transition evolves into two transitions, possibly associated with charge-density-wave and antiferromagnetic spin-density-wave orderings. These density-wave-like orders are gradually suppressed with pressure and, remarkably, a superconducting dome emerges at 3.65-8.0 GPa. The maximum of the superconducting transition temperature, Tcmax = 6.4 K, appears when the density-wave-like orders are completely suppressed at 4.2 GPa, and the normal state exhibits a non-Fermi-liquid behaviour, reminiscent of unconventional superconductivity and quantum criticality in iron-based superconductors17,18. Our work offers an unprecedented platform for investigating superconductivity in correlated kagome systems.

6.
Transgenic Res ; 33(4): 195-210, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39105946

RESUMO

Ethylene response factors have been shown to be involved in the effects of plant developmental processes and to regulate stress tolerance. The aim of this study was to recognize the regulatory mechanisms of ethylene response factors on tobacco plant height. In this study, a gene-edited mutant (ERF10-KO) and wild type (WT) were utilized as experimental materials. Transcriptome and metabolome analyses were used to investigate the regulatory mechanism of NtERF10 gene editing on plant height in tobacco. Here, through the analysis of differentially expressed genes (DEGs), 2051 genes were upregulated and 1965 genes were downregulated. We characterized the different ERF10-KO and WT plant heights and identified key genes for photosynthesis, the plant hormone signal transduction pathway and the terpene biosynthesis pathway. NtERF10 was found to affect the growth and development of tobacco by regulating the expression levels of the PSAA, PSBA, GLY17 and GGP3 genes. Amino acid metabolism was analyzed by combining analyses of differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs). In addition, we found that members of the bHLH, NAC, MYB, and WRKY transcription factor families have vital roles in regulating plant height. This study not only provides important insights into the positive regulation of the ethylene response factor NtERF10 on plant height during plant growth and development but also provides new research ideas for tobacco molecular breeding.


Assuntos
Regulação da Expressão Gênica de Plantas , Nicotiana , Proteínas de Plantas , Fatores de Transcrição , Nicotiana/genética , Nicotiana/crescimento & desenvolvimento , Nicotiana/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/genética , Etilenos/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Transcriptoma
7.
Zhonghua Nan Ke Xue ; 30(2): 128-131, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-39177345

RESUMO

Objective: To explore the influence of environment temperature on the incidence of testicular torsion. METHODS: We collected the clinical data on 172 cases of testicular torsion diagnosed in the Second Hospital of Hebei Medical University from December 2013 to December 2020. According to the local environment temperature on the day of onset, we divided the patients into groups A (below 0℃), B (0-10℃), C (10-20℃) and D (above 20℃), and compared the incidence rates of testicular torsion among the four groups, followed by correlation analysis. RESULTS: The incidence rate of testicular torsion was 12.8% (n = 22) in group A, 35.5% (n = 61) in B, 34.9% (n = 60) in C and 16.9% (n = 29) in D, the highest at 0-10℃ in group B, with statistically significant difference among the four groups (χ2 = 29.07, P <0.001). Spearman correlation analysis indicated that the incidence of testicular torsion was negatively correlated with the environment temperature (r = -0.261, P <0.01), with no statistically significant difference among different seasons (χ2 = 5.349, P >0.05), but higher in autumn and winter than in the other two seasons. CONCLUSION: The incidence of testicular torsion is negatively correlated with the environment temperature, elevated when the temperature decreases, but has no statistically significant difference among different seasons, though relatively higher in autumn and winter.


Assuntos
Estações do Ano , Torção do Cordão Espermático , Temperatura , Torção do Cordão Espermático/epidemiologia , Humanos , Masculino , Incidência
8.
Oncol Lett ; 28(3): 445, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39099584

RESUMO

Microsatellite instability (MSI) status is a prognostic biomarker for immunotherapy in certain types of cancers, such as colorectal cancers (CRCs) and endometrial cancers (ECs). Tumors that are categorized as having high MSI (MSI-H) express high levels of neoantigens for immune recognition. The typical MSI test measures the length of short mononucleotide repeats (SMR) poly(A) 21-27; however, a limitation of this test is the difficulty in determining the shift size, particularly in endometrial cancer. To investigate an MSI detection assay with improved performance, the present study analyzed the use of poly(A) 40-44 mononucleotide repeats to detect the MSI status of 100 patients with either CRC (n=50) or EC (n=50). Capillary electrophoresis was used to evaluate five long mononucleotide repeat (LMR) markers, including poly(A) 40-A, 40-B, 40-C, 40-D and 44. The concordance rate of the LMR-MSI assay compared with an immunohistochemistry MSI detection assay was 96.0 and 95.1% for CRCs and ECs respectively, with the detection limit of the LMR-MSI assay demonstrated to be 2.5% MSI-H in HCT116 colorectal carcinoma cell lines. The LMR-MSI assay yielded a 95.1% concordance rate in ECs compared with that in the SMR-MSI test (87.8%). The LMR-MSI test identified a significantly higher mean shift size (13 bp) in MSI-H tumors compared with the SMR-MSI test (10 bp), in both EC and CRC tissue samples. Together, the present study suggested that the LMR-MSI test could potentially be a sensitive and practical technology for molecular laboratory testing, particularly in the use of immunotherapy for patients with CRCs and ECs.

9.
Front Pharmacol ; 15: 1399598, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39108760

RESUMO

The liver, a complex parenchymal organ, possesses a distinctive microcirculatory system crucial for its physiological functions. An intricate interplay exists between hepatic microcirculatory disturbance and the manifestation of pathological features in diverse liver diseases. This review updates the main characteristics of hepatic microcirculatory disturbance, including hepatic sinusoidal capillarization, narrowing of sinusoidal space, portal hypertension, and pathological angiogenesis, as well as their formation mechanisms. It also summarized the detection methods for hepatic microcirculation. Simultaneously, we have also reviewed the characteristics of microcirculatory disturbance in diverse liver diseases such as acute liver failure, hepatic ischemia-reperfusion injury, viral hepatitis, non-alcoholic fatty liver disease, hepatic fibrosis, hepatic cirrhosis, and hepatocellular carcinoma. Finally, this review also summarizes the advancement in hepatic microcirculation attributed to traditional Chinese medicine (TCM) and its active metabolites, providing novel insights into the application of TCM in treating liver diseases.

10.
World J Clin Cases ; 12(22): 5067-5082, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39109018

RESUMO

BACKGROUND: Currently, traditional Chinese medicine (TCM) formulas are commonly being used as adjunctive therapy for ulcerative colitis in China. Network meta-analysis, a quantitative and comprehensive analytical method, can systematically compare the effects of different adjunctive treatment options for ulcerative colitis, providing scientific evidence for clinical decision-making. AIM: To evaluate the clinical efficacy and safety of commonly used TCM for the treatment of ulcerative colitis (UC) in clinical practice through a network meta-analysis. METHODS: Clinical randomized controlled trials of these TCM formulas used for the adjuvant treatment of UC were searched from the establishment of the databases to July 1, 2022. Studies that met the inclusion criteria were screened and evaluated for literature quality and risk of bias according to the Cochrane 5.1 standard. The methodological quality of the studies was assessed using ReviewManager (RevMan) 5.4, and a funnel plot was constructed to test for publication bias. ADDIS 1.16 statistical software was used to perform statistical analysis of the treatment measures and derive the network relationship and ranking diagrams of the various intervention measures. RESULTS: A total of 64 randomized controlled trials involving 5456 patients with UC were included in this study. The adjuvant treatment of UC using five TCM formulations was able to improve the clinical outcome of the patients. Adjuvant treatment with Baitouweng decoction (BTWT) showed a significant effect [mean difference = 36.22, 95% confidence interval (CI): 7.63 to 65.76]. For the reduction of tumor necrosis factor in patients with UC, adjunctive therapy with BTWT (mean difference = -9.55, 95%CI: -17.89 to -1.41), Shenlingbaizhu powder [SLBZS; odds ratio (OR) = 0.19, 95%CI: 0.08 to 0.39], and Shaoyao decoction (OR = -23.02, 95%CI: -33.64 to -13.14) was effective. Shaoyao decoction was more effective than BTWT (OR = 0.12, 95%CI: 0.03 to 0.39), SLBZS (OR = 0.19, 95%CI: 0.08 to 0. 39), and Xi Lei powder (OR = 0.34, 95%CI: 0.13 to 0.81) in reducing tumor necrosis factor and the recurrence rate of UC. CONCLUSION: TCM combined with mesalazine is more effective than mesalazine alone in the treatment of UC.

12.
Toxics ; 12(7)2024 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-39058157

RESUMO

Phthalate acid esters (PAEs) are one of the most widely used plasticizers globally, extensively employed in various decoration materials. However, studies on the impact of these materials on indoor environmental PAE pollution and their effects on human health are limited. In this study, forty dust samples were collected from four types of stores specializing in decoration materials (flooring, furniture boards, wall coverings, and household articles). The levels, sources, exposure doses, and potential health risks of PAEs in dust from decoration material stores were assessed. The total concentrations of Σ9PAE (the sum of nine PAEs) in dust from all decoration-material stores ranged from 46,100 ng/g to 695,000 ng/g, with a median concentration of 146,000 ng/g. DMP, DEP, DBP, and DEHP were identified as the predominant components. Among all stores, furniture board stores exhibited the highest Σ9PAE (159,000 ng/g, median value), while flooring stores exhibited the lowest (95,300 ng/g). Principal component analysis (PCA) showed that decoration materials are important sources of PAEs in the indoor environment. The estimated daily intakes of PAEs through non-dietary dust ingestion and dermal-absorption pathways among staff in various decoration-material stores were 60.0 and 0.470 ng/kg-bw/day (flooring stores), 113 and 0.780 ng/kg-bw/day (furniture board stores), 102 and 0.510 ng/kg-bw/day (wall covering stores), and 114 and 0.710 ng/kg-bw/day (household article stores). Particularly, staff in wall-covering and furniture-board stores exhibited relatively higher exposure doses of DEHP. Risk assessment indicated that although certain PAEs posed potential health risks, the exposure levels for staff in decoration material stores were within acceptable limits. However, staff in wall covering stores exhibited relatively higher risks, necessitating targeted risk-management strategies. This study provides new insights into understanding the risk associated with PAEs in indoor environments.

13.
Transl Stroke Res ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028413

RESUMO

Ischemic stroke can lead to systemic inflammation, which can activate peripheral immune cells, causing neuroinflammation and brain injury. Meningeal lymphatics play a crucial role in transporting solutes and immune cells out of the brain and draining them into cervical lymph nodes (CLNs). However, the role of meningeal lymphatics in regulating systemic inflammation during the reperfusion stage after ischemia is not well understood. In this study, we demonstrated that brain infarct size, neuronal loss, and the effector function of inflammatory macrophage subsets were reduced after ischemia-reperfusion and disruption of meningeal lymphatics. Spatial memory function was improved in the late stage of ischemic stroke following meningeal lymphatic disruption. Brain-infiltrating immune cells, including neutrophils, monocytes, and T and natural killer cells, were reduced after cerebral ischemia-reperfusion and meningeal lymphatic disruption. Single-cell RNA sequencing analysis revealed that meningeal lymphatic disruption reprogrammed the transcriptome profile related to chemotaxis and leukocyte migration in CLN lymphatic endothelial cells (LECs), and it also decreased chemotactic CCN1 expression in floor LECs. Replenishment of CCN1 through intraventricular injection increased brain infarct size and neuronal loss, while restoring numbers of macrophages/microglia in the brains of meningeal lymphatic-disrupted mice after ischemic stroke. Blocking CCN1 in cerebrospinal fluid reduced brain infarcts and improves spatial memory function after ischemia-reperfusion injury. In summary, this study indicates that CCN1-mediated detrimental inflammation was alleviated after cerebral ischemia-reperfusion injury and meningeal lymphatic disruption. CCN1 represents a novel therapeutic target for inhibiting systemic inflammation in the brain-CLN axis after ischemia-reperfusion injury.

14.
Food Res Int ; 190: 113905, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945555

RESUMO

Bee bread is a product of honeybees, which collect and ferment pollen, that contains highly nutritious and easily digestible active substances. However, its nutritional composition varies significantly with fermentation strains and seasonal changes. To unveil the patterns of microbial community and nutritional component changes in bee bread across seasons, we employed high-throughput techniques to assess the diversity of bacteria and fungi in bee bread. The results indicated that the compositions of bacteria and fungi in bee bread undergo significant seasonal variation, with noticeable changes in the microbial diversity of bee bread from different bee species. Subsequently, metabolomic analysis revealed high activity of glycerophospholipid metabolism in bee bread. Furthermore, our analysis identifaied noteworthy differences in nutritional components, including pH values, sugar content, and free amino acid levels, in bee bread across different seasons.


Assuntos
Bactérias , Microbiota , Valor Nutritivo , Estações do Ano , Abelhas/microbiologia , Animais , Bactérias/classificação , Fermentação , Aminoácidos/análise , Fungos/classificação , Pólen/química , Pão/análise , Pão/microbiologia , Concentração de Íons de Hidrogênio , Metabolômica
15.
Chemosphere ; 362: 142565, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38871187

RESUMO

Compared to the particle-gas partition coefficients (KPG), the rain-gas (KRG) and snow-gas (KSG) partition coefficients are also essential in studying the environmental behavior and fate of chemicals in the atmosphere. While the temperature dependence for the KPG have been extensively studied, the study for KRG and KSG are still lacking. Adsorption coefficients between water surface-air (KIA) and snow surface-air (KJA), as well as partition coefficients between water-air (KWA) and octanol-air (KOA) are vital in calculating KRG and KSG. These four basic adsorption and partition coefficients are also temperature-dependent, given by the well-known two-parameters Antoine equation logKXY = AXY + BXY/T, where KXY is the adsorption or partition coefficients, AXY and BXY are Antoine parameters (XY stand for IA, JA, WA, and OA), and T is the temperature in Kelvin. In this study, the parameters AXY and BXY are calculated for 943 chemicals, and logKXY can be estimated at any ambient temperature for these chemicals using these Antoine parameters. The results are evaluated by comparing these data with published experimental and modeled data, and the results show reasonable accuracy. Based on these coefficients, temperature-dependence of logKRG and logKSG is studied. It is found that both logKRG and logKSG are linearly related to 1/T, and Antoine parameters for logKRG and logKSG are also estimated. Distributions of the 943 chemicals in the atmospheric phases (gas, particle, and rain/snow), are illustrated in a Chemical Space Map. The findings reveal that, at environmental temperatures and precipitation days, the dominant state for the majority of chemicals is the gaseous phase. All the AXY and BXY values for logKSG, logKRG, and basic adsorption and partition coefficients, both modeled by this study and collected from published work, are systematically organized into an accessible dataset for public utilization.


Assuntos
Chuva , Neve , Temperatura , Neve/química , Chuva/química , Adsorção , Gases/química , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/química , Atmosfera/química , Monitoramento Ambiental/métodos , Água/química
16.
J Obstet Gynaecol Can ; : 102585, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38878822

RESUMO

OBJECTIVES: This study investigates experiences of medical students across Canada related to consent for educational sensitive (i.e., pelvic, rectal) exams under anesthesia (EUAs). METHODS: A bilingual online questionnaire was developed and distributed to medical students across Canada. RESULTS: Of 134 respondents, 63% had performed a pelvic EUA, 35% a rectal EUA, and 11% another sensitive EUA during their training. For those who had performed pelvic EUA, 28% were unsure if consent had taken place, 26% reported no specific consent, 20% reported specific consent, and 25% had mixed experiences of consent. For rectal EUAs, 48% reported no specific consent, 37% were unsure if consent had taken place, 13% reported that there had been specific consent, and 2% reported mixed experiences. Most respondents were uncomfortable (36%) or not sure if they were comfortable (32%) with how the consent process was handled for student pelvic EUAs; 31% were comfortable. In open-ended responses, respondents described experiences related to variability, discomfort, and authority. CONCLUSIONS: Non-consensual educational sensitive EUAs continue to take place in medical training across Canada, although practices of consent are highly variable. The majority of respondents reported being uncomfortable or unsure if they were comfortable with how consent for educational sensitive EUAs was practised during their training, and some respondents struggled to express their discomfort given the power dynamics at play.

17.
Chem Commun (Camb) ; 60(51): 6556-6559, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38845407

RESUMO

Herein, a novel strategy is presented for the photoinduced decarboxylative and dehydrogenative cross-coupling of a wide range of α-fluoroacrylic acids with hydrogermanes. This methodology provides an efficient and robust approach for producing various germylated monofluoroalkenes with excellent stereoselectivity within a brief photoirradiation period. The feasibility of this reaction has been demonstrated through gram-scale reaction, conversion of germylated monofluoroalkenes, and modification of complex organic molecules.

18.
ACS Chem Biol ; 19(6): 1237-1242, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38723147

RESUMO

As an important functional monosaccharide, glucosamine (GlcN) is widely used in fields such as medicine, food nutrition, and health care. Here, we report a distinct GlcN biosynthesis method that utilizes engineered Bacillus subtilis glucosamine-6-phosphate synthase (BsGlmS) to convert D-fructose to directly generate GlcN. The best variant obtained by using a combinatorial active-site saturation test/iterative saturation mutagenesis (CAST/ISM) strategy was a quadruple mutant S596D/V597G/S347H/G299Q (BsGlmS-BK19), which has a catalytic activity 1736-fold that of the wild type toward D-fructose. Upon using mutant BK19 as a whole-cell catalyst, D-fructose was converted into GlcN with 65.32% conversion in 6 h, whereas the wild type only attained a conversion rate of 0.31% under the same conditions. Molecular docking and molecular dynamics simulations were implemented to provide insights into the mechanism underlying the enhanced activity of BK19. Importantly, the BsGlmS-BK19 variant specifically catalyzes D-fructose without the need for phosphorylated substrates, representing a significant advancement in GlcN biosynthesis.


Assuntos
Bacillus subtilis , Glucosamina , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante) , Engenharia de Proteínas , Glucosamina/biossíntese , Glucosamina/metabolismo , Glucosamina/química , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/química , Bacillus subtilis/enzimologia , Bacillus subtilis/metabolismo , Bacillus subtilis/genética , Simulação de Acoplamento Molecular , Frutose/metabolismo , Frutose/química , Frutose/biossíntese , Simulação de Dinâmica Molecular , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Domínio Catalítico
19.
J Hazard Mater ; 473: 134643, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38776815

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) have the capability for solar radiation absorption related to climate forcing. Herein, pollution characteristics and absorption spectra of size-resolved PAHs in atmospheric particles in a cold megacity were comprehensively investigated. The mean concentrations of Σ18PAHs in all the 11 particle size ranges were 3.95 ± 4.77 × 104 pg/m3 and 2.17 ± 1.54 × 103 pg/m3 in heating period (HP) and non-heating period (NHP), respectively. Except for most PAHs with 2 and 3 benzene rings in NHP, most other PAHs showed a unimodal distribution pattern with the peak at 0.56-1.0 µm in both periods, which was caused by PAH emission sources. The PAH-related climate forcing was mainly caused by the solar radiation absorptions at ∼325 (∼330) nm and ∼365 nm. In general, the absorption intensities were higher in HP than NHP. The absorption intensity in the particle size range of 0.56-1.0 µm was the highest, and benzo[e]pyrene was the dominant contributor. In colder periods in HP, higher PAH concentrations caused more intensive PAH-related climate forcing. This study provided new insights for pollution characteristics and absorption spectra of size-resolved PAHs in atmospheric particles, which will be useful for better understanding PAH-related climate forcing.

20.
Surgery ; 176(2): 499-510, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38811326

RESUMO

BACKGROUND: Emodin, a natural anthraquinone derivative found in various Chinese medicinal herbs, has been proved to be an effective therapeutic agent in the treatment of many diseases. However, its effect on lung injury after intestinal ischemia/reperfusion injury remains unknown. This research was designed to investigate whether emodin protects against intestinal ischemia/reperfusion-induced lung injury and to elucidate the underlying molecular mechanisms in vivo and in vitro. METHODS: Intestinal ischemia/reperfusion injury was induced by occluding the superior mesenteric artery in mice, and mouse lung epithelial-12 cells were subjected to oxygen-glucose deprivation and reoxygenation to establish an in vitro model. RESULTS: Our data indicated that emodin treatment reduced intestinal ischemia/reperfusion-induced oxidative stress, inflammation and apoptosis in lung tissues and alleviated lung injury. However, the protective effects of emodin on intestinal ischemia/reperfusion-induced lung injury were reversed by the protein kinase B inhibitor triciribine or the heme oxygenase-1 inhibitor tin protoporphyrin IX. The protein kinase inhibitor triciribine also downregulated the expression of heme oxygenase-1. CONCLUSION: In conclusion, our data suggest that emodin treatment protects against intestinal ischemia/reperfusion-induced lung injury by enhancing heme oxygenase-1 expression via activation of the PI3K/protein kinase pathway. Emodin may act as a potential therapeutic agent for the prevention and treatment of lung injury induced by intestinal ischemia/reperfusion.


Assuntos
Emodina , Heme Oxigenase-1 , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Traumatismo por Reperfusão , Transdução de Sinais , Regulação para Cima , Animais , Emodina/farmacologia , Emodina/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/tratamento farmacológico , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Heme Oxigenase-1/metabolismo , Masculino , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Intestinos/irrigação sanguínea , Intestinos/patologia , Intestinos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Lesão Pulmonar/etiologia , Lesão Pulmonar/prevenção & controle , Lesão Pulmonar/metabolismo , Lesão Pulmonar/tratamento farmacológico , Lesão Pulmonar/patologia , Modelos Animais de Doenças , Estresse Oxidativo/efeitos dos fármacos , Proteínas de Membrana
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