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1.
Chem Commun (Camb) ; 60(53): 6753-6756, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38863330

RESUMO

An efficient Rh(III)-catalyzed enantioselective C-H alkynylation of isoquinolines is disclosed. The C-H alkynylation of 1-aryl isoquinolines with hypervalent iodine-alkyne reagents proceeded in DMA at room temperature in the presence of 2.5 mol% chiral SCpRh(III) complex along with 20 mol% AgSbF6, providing axially chiral alkynylated 1-aryl isoquinolines in excellent yields (up to 93%) and enantioselectivity (up to 95% ee). The diverse transformations of the product further enhance the potential utility of this reaction.

2.
Environ Int ; 190: 108841, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38917626

RESUMO

OBJECTIVES: Evidence on the link between long-term ambient particulate matter (PM) exposures and childhood sleep disorders were scarce. We examined the associations between long-term exposures to PM2.5 and PM1 (PM with an aerodynamic equivalent diameter <2.5 µm and <1 µm, respectively) with sleep disorders in children. METHODS: We performed a population-based cross-sectional survey in 177,263 children aged 6 to 18 years in 14 Chinese cities during 2012-2018. A satellite-based spatiotemporal model was employed to estimate four-year annual average PM2.5 and PM1 exposures at residential and school addresses. Parents or guardians completed a checklist using the Sleep Disturbance Scale for Children. We estimated the associations using generalized linear mixed models with adjustment for characteristics of children, parents, and indoor environments. RESULTS: Long-term PM2.5 and PM1 exposures were positively associated with odds of sleep disorders for almost all domains. For example, increments in PM2.5 and PM1 per 10 µg/m3 were associated with odds ratios of global sleep disorder of 1.24 (95 % confidence interval [CI]: 1.14, 1.35) and 1.31 (95 %CI: 1.18, 1.46), respectively. Similar results were observed for subtypes of sleep disorder. These associations were heterogeneous regionally, with stronger associations among children residing in southeast region than in northeast and northwest regions. Moreover, larger estimates of PM1 were found than that of PM2.5 in southeast region. CONCLUSION: Long-term PM2.5 and PM1 exposures are independently associated with higher risks of childhood sleep disorders, and these associations vary by geographical region.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38898267

RESUMO

BACKGROUND: Obesity is a major health concern worldwide. Previous studies have suggested that phthalate plasticizers are obesogens. However, the relationship between early-life phthalate exposure and long-term obesity development remains unknown. OBJECTIVE: We investigated the association between prenatal phthalate exposure and children's body mass index (BMI) patterns in an 18-year birth cohort follow-up study in Taiwan. METHODS: Our analytical lab quantified seven phthalate metabolites in maternal urine during pregnancy using quantitative liquid chromatography-tandem mass spectrometry. In addition, we calculated BMI z scores for participated children at each follow-up, utilized trajectory analysis to describe children's BMI z-score patterns at 2-18 years of age, and adopted generalized estimating equations (GEE) and multivariate logistic regression models to assess the association between prenatal phthalate exposure and BMI z scores in children. RESULTS: A total of 208 mother-child pairs were included in the analysis. Maternal urinary diethyl phthalate (DEP) metabolites were associated with the increase of BMI z scores in children aged 2-18 years in the GEE model. Doubled maternal urinary ∑mDEHP (3 mono hexyl-metabolites of di-ethyl-hexyl phthalate (DEHP) increased the risk of children being in the stable-high BMI trajectory group until the age of eighteen. IMPACT STATEMENT: We observed that BMI trajectories of children remained stable after the age of 5 years. During each follow-up, a higher frequency of overweight or obese was observed in children, ranging from 15.9% to 35.6% for girls and 15.2-32.0% for boys, respectively. Prenatal phthalate exposure was associated with increasing BMI z scores in children. Prenatal DEHP exposure was associated with a stable-high BMI trajectory in children up to the age of 18 years.

4.
Psychiatry Res ; 338: 115979, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38850891

RESUMO

The depression response trajectory after a course of repetitive transcranial magnetic stimulation(rTMS) remains understudied. We searched for blinded randomized controlled trials(RCTs) that examined conventional rTMS over left dorsolateral prefrontal cortex(DLPFC) for major depressive episodes(MDE). The effect size was calculated as the difference in depression improvement, between active and sham rTMS. We conducted a random-effects dose-response meta-analysis to model the response trajectory from the beginning of rTMS to the post-treatment follow-up phase. The area under curve (AUC) of the first 8-week response trajectory was calculated to compare antidepressant efficacy between different rTMS protocols. We included 40 RCTs(n = 2012). The best-fitting trajectory model exhibited a logarithmic curve(X2=17.7, P < 0.001), showing a gradual ascent with tapering off around the 3-4th week mark and maintaining until week 16. The maximum effect size was 6.1(95 %CI: 1.25-10.96) at week 16. The subgroup analyses showed distinct trajectories across different rTMS protocols. Besides, the comparisons of AUC showed that conventional rTMS protocols with more pulse/session group or more total pulses were associated with greater efficacy than those with fewer pulse/session or fewer total pulses, respectively. A course of conventional left DLPFC rTMS could lead to both acute antidepressant effects and sustained after-effects, which were modeled by different rTMS protocols in MDE.


Assuntos
Transtorno Depressivo Maior , Córtex Pré-Frontal Dorsolateral , Estimulação Magnética Transcraniana , Humanos , Transtorno Depressivo Maior/terapia , Estimulação Magnética Transcraniana/métodos , Córtex Pré-Frontal Dorsolateral/fisiologia , Córtex Pré-Frontal , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
J Am Chem Soc ; 146(25): 16982-16989, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38870424

RESUMO

Catalytic asymmetric dearomatization (CADA) reactions have evolved into an efficient strategy for accessing chiral polycyclic and spirocyclic scaffolds from readily available planar aromatics. Despite the significant developments, the CADA reaction of naphthalenes remains underdeveloped. Herein, we report a Gd(III)-catalyzed asymmetric dearomatization reaction of naphthalene with a chiral PyBox ligand via visible-light-enabled [4 + 2] cycloaddition. This reaction features application of a chiral Gd/PyBox complex, which regulates the reactivity and selectivity simultaneously, in excited-state catalysis. A wide range of functional groups is compatible with this protocol, giving the highly enantioenriched bridged polycycles in excellent yields (up to 96%) and selectivity (up to >20:1 chemoselectivity, >20:1 dr, >99% ee). The synthetic utility is demonstrated by a 2 mmol scale reaction, removal of directing group, and diversifications of products. Preliminary mechanistic experiments are performed to elucidate the reaction mechanism.

6.
Child Care Health Dev ; 50(3): e13270, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38706405

RESUMO

INTRODUCTION: Chronic physical disease (CPD) makes life filled with many negative events in adolescents, but not all adolescents experiencing negative life events proceed to develop emotional distress, only those with low emotional distress tolerance (EDT). A valid and reliable scale to measure EDT in CPD adolescents is important for caring for their emotional distress. Therefore, the purpose of this study is to translate the 15-item English version Distress Tolerance Scale (DTS) into a Chinese version and then validate the scale for measuring EDT of adolescents with CPD. METHODS: The 15-item English version DTS was translated into a Chinese version using the translation guidelines for cross-cultural research. Two cohorts of adolescents with CPD were recruited from four hospitals in southern Taiwan, with the first cohort including 124 adolescents with CPD employed to conduct exploratory factor analysis, corrected item-total correlation and reliability testing, while the second cohort, consisting of 238 adolescents with CPD, was utilized to examine confirmatory factor analysis and concurrent validity. RESULTS: The two-factor nine-item Chinese version DTS for Adolescents with CPD (C-DTS-A) was developed. Lower scores of the C-DTS-A were significantly associated with higher diabetes distress, poorer self-management, and worse glycaemic control; their correlation coefficients sequentially were -.40, .17 and -.23. Cronbach's α and the test-retest reliability of the two-factor C-DTS-A ranged from .81 to .87 and from .79 to .89, respectively. CONCLUSION: The two-factor nine-item C-DTS-A with good cross-cultural translation quality was a reliable and valid scale to assess EDT for adolescents with CPD.


Assuntos
Comparação Transcultural , Angústia Psicológica , Psicometria , Traduções , Humanos , Adolescente , Feminino , Masculino , Reprodutibilidade dos Testes , Doença Crônica , Taiwan , Inquéritos e Questionários/normas , Estresse Psicológico/diagnóstico , Análise Fatorial , Tradução
7.
Huan Jing Ke Xue ; 45(5): 3098-3106, 2024 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-38629570

RESUMO

In recent years, the environmental pollution of microplastics in Poyang Lake has received increasing attention. Baisha Lake of Poyang Lake was selected as the study area, and samples of water and sediments of Baisha Lake and the microplastics therein were collected, and the polymer types of microplastics were identified as polyethylene (PE), polyester (PET), polypropylene (PP), and polystyrene (PS) using Fourier infrared spectroscopy. We also analyzed the structural composition of bacterial communities in water, in sediments, and on microplastic surfaces using 16S high-throughput sequencing. The species richness and diversity of bacteria on the microplastic surfaces were lower than those in the surrounding water and sediments. The results of NMDS analysis showed that the bacterial community structures on the microplastic surfaces differed greatly from those in the surrounding sediments and water. The bacterial community composition in water and sediment differed from that on the microplastic surfaces, and the dominant bacterial phyla on the microplastic surfaces were Proteobacteria and Bacteroidota, and their relative abundance on the microplastic surfaces was higher than that in sediment. The relative abundance of Proteobacteria was higher than that in water. The relative abundances of Bacteroidota and Actinobacteriota were significantly lower than that of water. Massilia and Pseudomonas were the dominant genera on the microplastic surfaces, and their relative abundances were significantly higher than those in the surrounding water and sediments. BugBase phenotype prediction revealed that the relative abundance of contains mobile elements, biofilm formation, potential pathogenicity, and stress tolerance phenotypes of microplastic bacterial communities were significantly higher than those of the surrounding water and sediments. The results revealed that microplastics may have contributed to the spread of harmful bacteria, including pathogenic bacteria, and increased the potential pathogenicity of bacterial communities. Additionally, microplastic surface bacterial communities had higher phenotypes of mobile gene element content. Revealing the potential harm of microplastic pollution to wetland ecology at the micro level may provide a scientific reference for maintaining the ecological stability of wetlands.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos/análise , Lagos/química , Monitoramento Ambiental , Água/análise , Bactérias/genética , Proteobactérias , China , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química
8.
J Hazard Mater ; 470: 134226, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38593665

RESUMO

Contaminants may induce immune response polarization, leading to immune diseases, such as allergic diseases. Evidence concerning the effects of chlorinated paraffins (CPs), an emerging persistent organic pollutant, on immune system is scarce, particularly for epidemiological evidence. This study explores the association between CPs exposure and allergic diseases (allergic rhinitis, atopic eczema, and allergic conjunctivitis) in children and adolescents in the Pearl River Delta (PRD) in China. Herein, 131,304 children and adolescents from primary and secondary schools in the PRD were included and completed the questionnaire survey. The particulate matter (PM) samples were collected in the PRD and the PM2.5-bound CP concentrations were analyzed. In the multivarious adjustment mixed effect model (MEM), an IQR increase in ∑CPs was significantly associated with allergic diseases (rhinitis, eczema, and conjunctivitis) with the estimated odds ratios (ORs) for 1.11 (95% CI: 1.10, 1.13), 1.17 (95% CI: 1.15, 1.19), and 1.82 (95% CI: 1.76, 1.88), respectively. Interaction analysis indicated that overweight and obese individuals might have greater risk. Similar effect estimates were observed in several sensitivity analyses. This study provided epidemiological evidence on the immunotoxicity of CPs. More studies to confirm our findings and investigate mechanisms are needed.


Assuntos
Parafina , Humanos , Adolescente , Criança , Masculino , Feminino , China/epidemiologia , Parafina/toxicidade , Parafina/análise , Hipersensibilidade/epidemiologia , Exposição Ambiental/efeitos adversos , Hidrocarbonetos Clorados/toxicidade , Hidrocarbonetos Clorados/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Material Particulado/toxicidade , Material Particulado/análise , Dermatite Atópica/epidemiologia , Dermatite Atópica/induzido quimicamente , Rinite Alérgica/epidemiologia , Rinite Alérgica/induzido quimicamente
9.
PLoS One ; 19(3): e0297631, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38483929

RESUMO

BACKGROUND: Newborn anogenital distance (AGD) has been associated with prenatal exposure of phthalates. The association between prenatal phthalate exposure and sex steroid hormones in newborns is unclear. OBJECT: This study aimed to examine whether cord-blood sex hormone levels were associated with prenatal phthalate exposure and newborn anogenital distance (AGD). METHODS: In the Taiwan Maternal and Infant Cohort Study, we recruited 1,676 pregnant women in their third trimester in 2012-2015 in Taiwan. We determined 11 urinary phthalate metabolites in pregnant women, three maternal and five cord-blood steroid sex-hormone concentrations. Five hundred and sixty-five mother-infant pairs with sufficient data were included. Trained neonatologists measured 263 newborns' AGD. We examined the associations of prenatal phthalate metabolite levels with AGD and hormones using linear regression models and evaluated correlations between maternal and cord-blood sex hormone levels and AGD. RESULTS: Compared with the male newborns exposed to maternal phthalate metabolites at the first tertile, AGD was -3.75, -3.43, and -3.53 mm shorter among those exposed at the median tertile of di-2-ethylhexyl phthalate (DEHP) metabolites, monobenzyl phthalate (MBzP), and monomethyl phthalate (MMP), respectively. Compared with those who had exposed at the first tertile, cord-blood follicle-stimulating hormone (FSH) decreased among male newborns exposed at higher levels of MMP, mono-n-butyl phthalate (MnBP), MBzP and DEHP, and among female newborns exposed at higher levels of MMP, MBzP and mono(2-ethyl-5-hydroxyhexyl) phthalate. However, we did not observe significant correlations of maternal or cord-blood sex steroid hormones with newborns' AGDs. CONCLUSIONS: Alterations in cord-blood sex steroid hormone levels were associated with prenatal phthalate exposures, particularly in male newborns. Women aspiring to be pregnant should be alerted of the need of reducing phthalate exposure.


Assuntos
Dietilexilftalato , Poluentes Ambientais , Ácidos Ftálicos , Lactente , Humanos , Masculino , Feminino , Recém-Nascido , Gravidez , Estudos de Coortes , Taiwan , Ácidos Ftálicos/toxicidade , Ácidos Ftálicos/urina , Hormônios Esteroides Gonadais , Exposição Materna/efeitos adversos , Exposição Ambiental , Poluentes Ambientais/efeitos adversos
10.
Nat Commun ; 15(1): 2462, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38503749

RESUMO

Medium-sized-ring compounds have been recognized as challenging synthetic targets in organic chemistry. Especially, the difficulty of synthesis will be augmented if an E-olefin moiety is embedded. Recently, photo-induced dearomative cycloaddition reactions that proceed via energy transfer mechanism have witnessed significant developments and provided powerful methods for the organic transformations that are not easily realized under thermal conditions. Herein, we report an intramolecular dearomative [5 + 4] cycloaddition of naphthalene-derived vinylcyclopropanes under visible-light irradiation and a proper triplet photosensitizer. The reaction affords dearomatized polycyclic molecules possessing a nine-membered-ring with an E-olefin moiety in good yields (up to 86%) and stereoselectivity (up to 8.8/1 E/Z). Detailed computational studies reveal the origin behind the favorable formation of the thermodynamically less stable isomers. Diverse derivations of the dearomatized products have also been demonstrated.

11.
Eur J Med Res ; 29(1): 203, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38539276

RESUMO

OBJECTIVES: To investigate the association of albumin-corrected anion gap (ACAG) with non-alcoholic fatty liver disease (NAFLD) and clinically significant fibrosis (CSF) defined by vibration-controlled transient elastography measurements. METHODS: This cross-sectional study including 4531 participants was conducted using the data from the NHANES database of cycles 2017-2018. The outcomes were set as NAFLD vs. non-NAFLD and NAFLD with CSF vs. NAFLD without CSF. The generalized additive model and restricted cubic spline analyses were used to assess the nonlinear relationship. The generalized linear models, logistic regression models, sensitivity analysis, P trend test, subgroup analysis, and mediation analysis were employed to analyze the association. Finally, an ACAG-based model was constructed and evaluated. RESULTS: A higher ACAG level was an independent risk factor for NAFLD (P < 0.05), but not for CSF (P > 0.05). The sensitivity analysis and P trend test results substantiated the significantly positive relationship between ACAG and NAFLD (P < 0.05). Interestingly, the obvious connection between ACAG and NAFLD varied in different waist circumference groups and played a central role in the central obesity group. In addition, alanine aminotransferase and waist circumference were the mediators in their relationship. Moreover, the ACAG-based model performed well in predicting NAFLD. CONCLUSIONS: ACAG level is independently associated with NAFLD but not CSF. ACAG might be a novel and reliable biomarker for predicting NAFLD clinically especially in the central obesity population.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Estudos Transversais , Obesidade Abdominal/complicações , Inquéritos Nutricionais , Circunferência da Cintura , Equilíbrio Ácido-Base , Obesidade/complicações , Albuminas
12.
Chem Sci ; 15(11): 4114-4120, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38487217

RESUMO

C-H functionalization and dearomatization constitute fundamental transformations of aromatic compounds, which find wide applications in various research areas. However, achieving both transformations from the same substrates with a single catalyst by operating a distinct mechanism remains challenging. Here, we report a photocatalytic strategy to modulate the reaction pathways that can be directed toward either C-H functionalization or dearomatization under redox-neutral or net-reductive conditions, respectively. Two sets of indoles and indolines bearing tertiary alcohols are divergently furnished with good yields and high selectivity. The key to success is the introduction of isoazatruxene ITN-2 as a novel photocatalyst (PC), which outperforms the commonly used PCs. The ready synthesis and high modulability of isoazatruxene type PCs indicate their great application potential.

13.
J Am Chem Soc ; 146(7): 4333-4339, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38324359

RESUMO

Ru/Cu dual catalysis has been applied for Z-retentive asymmetric allylic substitution reactions of aldimine esters. This reaction provides an enantioselective synthesis of chiral Z-olefins in high yields (up to 91% yield) with excellent enantioselectivity (up to 98% ee) under mild conditions. The previously unreacted trisubstituted allylic electrophiles under Ir catalytic system are found to be compatible, affording the stereoretentive products in either Z- or E-form. Both linear and branched allylic electrophiles are suitable substrates with excellent reaction outcomes. Notably, Ru and Cu complexes are added in one-pot and simplifies the manipulation of this protocol and self-sorting phenomena could be observed in this Ru/Cu dual catalytic system.

14.
Sci Total Environ ; 921: 171224, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38402960

RESUMO

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.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Material Particulado/toxicidade , Material Particulado/análise , China , Mediadores da Inflamação , Tamanho da Partícula , Monitoramento Ambiental
15.
Chem Biodivers ; 21(3): e202400017, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38321767

RESUMO

Three undescribed isosteroidal alkaloids, przewalskines A-C (1-3), as well as seven known alkaloids (4-10) were obtained from Fritillaria przewalskii bulbs. Their structures were deduced by extensive HRESIMS, 1D NMR, and 2D NMR analyses, and their bioactivities were evaluated involving the anti-inflammatory and inhibitory potencies on AChE, BChE, and Aß aggregation. Compound 4 revealed the potent effect on inhibiting Aß aggregation activity with IC50 value of 33.1 µM, AChE activity with IC50 value of 6.9 µM, and also showed NO release inhibitory acitivity with IC50 value of 32.6 µM. These findings contribute new multi-.target anti-AD agents and embody the chemical diversity of F. przewalskii.


Assuntos
Alcaloides , Fritillaria , Fritillaria/química , Alcaloides/farmacologia , Alcaloides/química
16.
Org Lett ; 26(7): 1501-1505, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38349077

RESUMO

Asymmetric C-H trifluoromethylalkylation represents a novel and straightforward synthetic method for the construction of chiral CF3-containing compounds. However, the reported examples remain limited, given the challenges of reactivity and enantioselective control. Herein, we report a SCpRh(III)-catalyzed asymmetric aryl and alkenyl C-H trifluoromethylalkylation reaction with ß-trifluoromethyl-α,ß-unsaturated ketones. The chiral CF3-bearing adducts were obtained in moderate to good yields with high enantioselectivity (up to 81% yield and 96% ee). The reaction features mild conditions and broad substrate scope. The chiral CF3-bearing products could undergo diverse functional group transformations.

17.
Am J Cancer Res ; 14(1): 1-15, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38323271

RESUMO

Mast cells (MCs) have emerged as pivotal contributors to both the defensive immune response and immunomodulation. They also exhibit regulatory functions in modulating pathological processes across various allergic diseases. The impact of MC presence within tumor tissues has garnered considerable attention, yielding conflicting findings. While some studies propose that MCs within tumor tissues promote tumor initiation and progression, others advocate an opposing perspective. Notably, evidence emphasizes the dual role of MCs in cancer, both as promoters and suppressors, is crucial for optimizing cancer treatment strategies. These conflicting viewpoints have generated substantial controversy, underscoring the need for a comprehensive understanding of MC's role in tumor immune responses.

18.
Angew Chem Int Ed Engl ; 63(18): e202402109, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38421344

RESUMO

This review explores the pivotal role of sulfur in advancing sustainable carbon-carbon (C-C) coupling reactions. The unique electronic properties of sulfur, as a soft Lewis base with significant mesomeric effect make it an excellent candidate for initiating radical transformations, directing C-H-activation, and facilitating cycloaddition and C-S bond dissociation reactions. These attributes are crucial for developing waste-free methodologies in green chemistry. Our mini-review is focused on existing sulfur-directed C-C coupling techniques, emphasizing their sustainability and comparing state-of-the-art methods with traditional approaches. The review highlights the importance of this research in addressing current challenges in organic synthesis and catalysis. The innovative use of sulfur in photocatalytic, electrochemical and metal-catalyzed processes not only exemplifies significant advancements in the field but also opens new avenues for environmentally friendly chemical processes. By focusing on atom economy and waste minimization, the analysis provides broad appeal and potential for future developments in sustainable organic chemistry.

19.
Huan Jing Ke Xue ; 45(1): 470-479, 2024 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-38216496

RESUMO

Contaminants such as microplastics (MPs) and heavy metals are commonly found in soils, both of which are extremely difficult to degrade and can easily form compound contamination, altering the physicochemical properties of the soil and thus potentially changing the growth and physiological and ecological characteristics of plants. In order to study the effects of the combined contamination of soil MPs and heavy metals on soil properties and plant growth, polystyrene microplastics (PS-MPs) with a particle size of 3 µm and the heavy metal cadmium were selected in the study. The changes in the physicochemical properties of soil and their effects on lettuce (Lactuca sativa) seed germination and seedling growth were studied at various exposure concentrations of PS-MPs (0, 10, 50, 100, 200, and 400 mg·kg-1) and combined with different Cd contamination concentrations (0, 1.2, and 6.0 mg·kg-1), respectively. The results showed that soil organic matter (SOM), available phosphorus (AP), alkali-hydrolysable nitrogen (AHN), and available kalium (AK) showed significant decreases as the intensity of PS-MPs combined with Cd contamination increased. Simultaneously, PS-MPs combined with Cd contamination also significantly reduced the germination rate of lettuce seeds, but low concentrations of PS-MPs slowed down the effect of Cd (6.0 mg·kg-1) contamination on lettuce seeds, and high concentrations of PS-MPs enhanced the effect of Cd (6.0 mg·kg-1). The fresh weight, dry weight, and plant height of lettuce seedlings showed an increasing and then decreasing trend with increasing exposure to PS-MPs. Chlorophyll content, superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) showed a decreasing trend, whereas malondialdehyde (MDA) content showed an overall increasing trend under different Cd concentrations. The main physicochemical indicators of the soil were negatively correlated with MDA of lettuce seedlings, whereas other indicators of the seedlings were positively correlated. The combined contamination of PS-MPs and Cd could affect the germination of plant seeds and the physiological and ecological characteristics of seedlings by changing the physicochemical properties of the soil. Both exposure to single PS-MPs contaminants and the combination of PS-MPs with Cd inhibited the germination of lettuce seeds and affected the physiological activities of their seedlings, and the inhibition was significantly increased with increasing exposure. Low exposure to PS-MPs or the combination of PS-MPs with Cd contamination exhibited a promotive effect on lettuce seedling growth. High exposure to PS-MPs combined with Cd contamination exhibited significant ecological effects on lettuce seedlings, and high exposure to PS-MPs exacerbated the ecotoxicological effects of Cd contaminants on lettuce seedlings, and PS-MPs and Cd exhibited synergistic effects. The results can provide some reference for assessing the ecological effects of MPs and heavy metal pollution in soil-plant systems.


Assuntos
Metais Pesados , Poluentes do Solo , Cádmio/toxicidade , Cádmio/metabolismo , Microplásticos , Lactuca , Plásticos , Poliestirenos , Solo , Metais Pesados/metabolismo , Plântula , Poluentes do Solo/análise
20.
J Med Virol ; 96(1): e29323, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38164047

RESUMO

Enteroviruses (EVs), single-stranded, positive-sense RNA viruses, can be classified into four species (A-D), which have previously been linked to a diverse range of disease manifestations and infections affecting the central nervous system. In the Enterovirus species B (EV-B), Echovirus type 11 (E11) has been observed to occasionally circulate in Taiwan, which was responsible for an epidemic of enterovirus infections in 2018. Here, 48 clinical specimens isolated in 2003, 2004, 2009, and 2018 were collected for the high-throughput sequencing. Notably, we identified 2018 Taiwanese strains having potential recombinations in the 3D gene, as well as one 2003 strain having a double recombination with E6 and Coxsackievirus B5 in the P2 and P3 regions, respectively. Additionally, one amino acid signature mutated from the Histidine (H) in throat swab specimens to the Tyrosine (Y) in cerebral spinal fluid specimens was detected at position 1496 (or 57) of the genomic coordinate (or 3A gene) to further demonstrate intra-host evolution in different organs. In conclusion, this study identifies potential intertypic recombination events and an intra-host signature mutation in E11 strains, isolated during a 2018 neurological disease outbreak in Taiwan, contributing to our understanding of its evolution and pathogenesis.


Assuntos
Infecções por Enterovirus , Enterovirus , Humanos , Filogenia , Enterovirus Humano B/genética , Enterovirus/genética , Infecções por Enterovirus/epidemiologia , Recombinação Genética
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