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1.
J Fluoresc ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38460097

RESUMO

A novel nanocomposite fluorescent probe consisting of quantum dots and a silica molecularly imprinted polymer (MIPs-capped ZnS:Mn QDs) was synthesized and applied for the rapid detection of teflubenzuron (TBZ) based on the fluorescence quenching of a composite probe via TBZ. The fluorescence quenching efficiency of MIP@SiO2@ZnS:Mn QDs displayed a linear relationship over the concentration range of 0-26.24 µmol/L with a correlation coefficient of 0.9857 and the limit of detection was 2.4 µg/L. The selectivity test showed that the nanocomposite had good selectively rebind TBZ with higher imprinting factor of 3.06 compared with four structurally similar compounds. In addition, the probe was successfully applied to the detection of TBZ in vegetable samples with a recovery of 90.3~97.1% and with a relative standard deviation below 3.2%. This developed method has the advantages of simple preparation, fast response and low toxicity for trace TBZ detection.

2.
BMC Pediatr ; 24(1): 136, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38383331

RESUMO

OBJECTIVE: To explore the effect of repetitive transcranial magnetic stimulation (rTMS)-assisted training on lower limb motor function in children with hemiplegic cerebral palsy (HCP). METHOD: Thirty-one children with HCP who met the inclusion criteria were selected and randomly divided into a control group (n = 16) and an experimental group (n = 15). The control group received routine rehabilitation treatment for 30 min each time, twice a day, 5 days a week for 4 weeks. Based on the control group, the experimental group received rTMS for 20 min each time, once a day, 5 days a week for 4 weeks. The outcome measures included a 10-metre walk test (10MWT), a 6-minute walk distance (6MWD) test, D- and E-zone gross motor function measurements (GMFM), the symmetry ratio of the step length and stance time and the muscle tone of the triceps surae and the hamstrings (evaluated according to the modified Ashworth scale), which were obtained in both groups of children before and after treatment. RESULTS: After training, the 10MWT (P < 0.05), 6MWD (P < 0.01), GMFM (P < 0.001) and the symmetry ratio of the step length and stance time of the two groups were significantly improved (P < 0.05), there was more of an improvement in the experimental group compared with the control group. There was no significant change in the muscle tone of the hamstrings between the two groups before and after treatment (P > 0.05). After treatment, the muscle tone of the triceps surae in the experimental group was significantly reduced (P < 0.05), but there was no significant change in the control group (P > 0.05). CONCLUSION: Repetitive TMS-assisted training can improve lower limb motor function in children with HCP.


Assuntos
Paralisia Cerebral , Estimulação Magnética Transcraniana , Criança , Humanos , Hemiplegia/etiologia , Extremidade Inferior , Caminhada
3.
Mar Pollut Bull ; 200: 116140, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342000

RESUMO

China's coastal waters are confronting serious water quality problems, particularly the Hangzhou Bay in the Yangtze River Delta. To find out the underlying cause, we use the Regional Ocean Modeling System (ROMS) to simulate the hydrodynamic characteristics and the evolution of water pollutants. The results show that the hydrodynamic conditions are complicated and the semi-exchange time is 46 days, significantly hindering the dilution and diffusion of water pollutants. Concentrations of each typical pollutant as chemical oxygen demand (COD), dissolved inorganic nitrogen (DIN), and phosphate (PO4) decrease from west to east, showing an obvious enrichment in the coastal region. Source-oriented results show that the inland water pollution of the Yangtze River and the Qiantang River is the key contributor, and the sewage outfalls on the coast near the bay worsen the pollution. This suggests that the government needs to strengthen the management of sources that affect water security.


Assuntos
Poluentes Químicos da Água , Poluentes da Água , Monitoramento Ambiental/métodos , Baías , Hidrodinâmica , Poluentes Químicos da Água/análise , China , Nitrogênio/análise , Rios
4.
Artigo em Inglês | MEDLINE | ID: mdl-38414718

RESUMO

Purpose: The study comprehensively evaluated the prognostic roles of the platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), basophil-to-lymphocyte ratio (BLR), and eosinophil-to-lymphocyte ratio (ELR) in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). Patients and Methods: Six hundred and nineteen patients with AECOPD and 300 healthy volunteers were retrospectively included into the study. The clinical characteristics of the patients with AECOPD and the complete blood counts (CBCs) of the healthy volunteers were collected. The associations of PLR, NLR, MLR, BLR, and ELR with airflow limitation, hospital length of stay (LOS), C-reactive protein (CRP), and in-hospital mortality in patients with AECOPD were analyzed. Results: Compared with the healthy volunteers, PLR, NLR, MLR, BLR, and ELR were all elevated in COPD patients under stable condition. PLR, NLR, MLR, and BLR were further elevated while ELR was lowered during exacerbation. In the patients with AECOPD, PLR, NLR, and MLR were positively correlated with hospital LOS as well as CRP. In contrast, ELR was negatively correlated with hospital LOS as well as CRP. Elevated PLR, NLR, and MLR were all associated with more severe airflow limitation in AECOPD. Elevated PLR, NLR, and MLR were all associated with increased in-hospital mortality while elevated ELR was associated with decreased in-hospital mortality. Binary logistic regression analysis showed that smoking history, FEV1% predicted, pneumonia, pulmonary heart disease (PHD), uric acid (UA), albumin, and MLR were significant independent predictors ofin-hospital mortality. These predictors along with ELR were used to construct a nomogram for predicting in-hospital mortality in AECOPD. The nomogram had a C-index of 0.850 (95% CI: 0.799-0.901), and the calibration curve, decision curve analysis (DCA), and clinical impact curve (CIC) further demonstrated its good predictive value and clinical applicability. Conclusion: In summary, PLR, NLR, MLR, and ELR served as useful biomarkers in patients with AECOPD.


Assuntos
Neutrófilos , Doença Pulmonar Obstrutiva Crônica , Humanos , Monócitos , Eosinófilos , Estudos Retrospectivos , Linfócitos , Biomarcadores , Prognóstico , Proteína C-Reativa/análise
5.
Brain Res ; 1828: 148790, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38272156

RESUMO

A strong relationship between Alzheimer's disease (AD) and vascular dysfunction has been the focus of increasing attention in aging societies. In the present study, we examined the long-term effect of scallop-derived plasmalogen (sPlas) on vascular remodeling-related proteins in the brain of an AD with cerebral hypoperfusion (HP) mouse model. We demonstrated, for the first time, that cerebral HP activated the axis of the receptor for advanced glycation endproducts (RAGE)/phosphorylated signal transducer and activator of transcription 3 (pSTAT3)/provirus integration site for Moloney murine leukemia virus 1 (PIM1)/nuclear factor of activated T cells 1 (NFATc1), accounting for such cerebral vascular remodeling. Moreover, we also found that cerebral HP accelerated pSTAT3-mediated astrogliosis and activation of the nucleotide-binding domain and leucine-rich repeat protein 3 (NLRP3) inflammasome, probably leading to cognitive decline. On the other hand, sPlas treatment attenuated the activation of the pSTAT3/PIM1/NFATc1 axis independent of RAGE and significantly suppressed NLRP3 inflammasome activation, demonstrating the beneficial effect on AD.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Plasmalogênios , Fatores de Transcrição NFI/metabolismo , Inflamassomos/metabolismo , Fator de Transcrição STAT3/metabolismo , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Remodelação Vascular
6.
Anal Chem ; 96(2): 847-855, 2024 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-38159051

RESUMO

RNA molecules undergo various chemical modifications that play critical roles in a wide range of biological processes. N6,N6-Dimethyladenosine (m6,6A) is a conserved RNA modification and is essential for the processing of rRNA. To gain a deeper understanding of the functions of m6,6A, site-specific and accurate quantification of this modification in RNA is indispensable. In this study, we developed an AlkB-facilitated demethylation (AD-m6,6A) method for the site-specific detection and quantification of m6,6A in RNA. The N6,N6-dimethyl groups in m6,6A can cause reverse transcription to stall at the m6,6A site, resulting in truncated cDNA. However, we found that Escherichia coli AlkB demethylase can effectively demethylate m6,6A in RNA, generating full-length cDNA from AlkB-treated RNA. By quantifying the amount of full-length cDNA produced using quantitative real-time PCR, we were able to achieve site-specific detection and quantification of m6,6A in RNA. Using the AD-m6,6A method, we successfully detected and quantified m6,6A at position 1851 of 18S rRNA and position 937 of mitochondrial 12S rRNA in human cells. Additionally, we found that the level of m6,6A at position 1007 of mitochondrial 12S rRNA was significantly reduced in lung tissues from sleep-deprived mice compared with control mice. Overall, the AD-m6,6A method provides a valuable tool for easy, accurate, quantitative, and site-specific detection of m6,6A in RNA, which can aid in uncovering the functions of m6,6A in human diseases.


Assuntos
Proteínas de Escherichia coli , RNA , Humanos , Animais , Camundongos , RNA/química , Adenosina/química , DNA Complementar , Metilação , Escherichia coli/genética , Escherichia coli/metabolismo , Desmetilação , Oxigenases de Função Mista
7.
Acta Pharm Sin B ; 13(12): 4963-4982, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38045063

RESUMO

Endocrine-resistance remains a major challenge in estrogen receptor α positive (ERα+) breast cancer (BC) treatment and constitutively active somatic mutations in ERα are a common mechanism. There is an urgent need to develop novel drugs with new mode of mechanism to fight endocrine-resistance. Given aberrant ERα activity, we herein report the identification of novel covalent selective estrogen receptor degraders (cSERDs) possessing the advantages of both covalent and degradation strategies. A highly potent cSERD 29c was identified with superior anti-proliferative activity than fulvestrant against a panel of ERα+ breast cancer cell lines including mutant ERα. Crystal structure of ERα‒29c complex alongside intact mass spectrometry revealed that 29c disrupted ERα protein homeostasis through covalent targeting C530 and strong hydrophobic interaction collied on H11, thus enforcing a unique antagonist conformation and driving the ERα degradation. These significant effects of the cSERD on ERα homeostasis, unlike typical ERα degraders that occur directly via long side chains perturbing the morphology of H12, demonstrating a distinct mechanism of action (MoA). In vivo, 29c showed potent antitumor activity in MCF-7 tumor xenograft models and low toxicity. This proof-of-principle study verifies that novel cSERDs offering new opportunities for the development of innovative therapies for endocrine-resistant BC.

8.
Life (Basel) ; 13(11)2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-38004274

RESUMO

Reduced-oxidation-state phosphorus (reduced P, hereafter) compounds were likely available on the early Earth via meteorites or through various geologic processes. Due to their reactivity and high solubility, these compounds could have played a significant role in the origin of various organophosphorus compounds of biochemical significance. In the present work, we study the reactions between reduced P compounds and their oxidation products, with the three nucleosides (uridine, adenosine, and cytidine), with organic alcohols (glycerol and ethanolamine), and with the tertiary ammonium organic compound, choline chloride. These reactions were studied in the non-aqueous solvent formamide and in a semi-aqueous solvent comprised of urea: ammonium formate: water (UAFW, hereafter) at temperatures of 55-68 °C. The inorganic P compounds generated through Fenton chemistry readily dissolve in the non-aqueous and semi-aqueous solvents and react with organics to form organophosphites and organophosphates, including those which are identified as phosphate diesters. This dual approach (1) use of non-aqueous and semi-aqueous solvents and (2) use of a reactive inorganic P source to promote phosphorylation and phosphonylation reactions of organics readily promoted anhydrous chemistry and condensation reactions, without requiring any additive, catalyst, or other promoting agent under mild heating conditions. We also present a comparative study of the release of P from various prebiotically relevant phosphate minerals and phosphite salts (e.g., vivianite, apatite, and phosphites of iron and calcium) into formamide and UAFW. These results have direct implications for the origin of biological P compounds from non-aqueous solvents of prebiotic provenance.

9.
Brain Behav ; 13(12): e3298, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37872861

RESUMO

INTRODUCTION: Numerous studies have found that expert players anticipate better than novices. If more accurate prediction represents performance monitoring of experts, what are the advantages of elite basketball players in identifying and processing available cues? There is still a lack of sufficient evidence. This study examined the visual search in basketball players and explored the performance monitoring of action anticipation, adopting an expert-novice paradigm and eye-movement technology. METHODS: Forty basketball players were recruited in this study: 20 in the expert group and 20 in the novice group. Participants were asked to predict the outcome of videotaped basketball throws and their accuracy and eye-movement characteristics were record. RESULTS: The accuracy of the expert was significantly higher than that of the novice. The experts were able to instantly search and identify important cues in anticipation, and the gaze area of the experts was concentrated on the area of interest of the body. Additionally, the expert group showed long, repetitive, and rapid visual search of vital information, and improved their performance of the task. CONCLUSION: The experts could monitor the performance of prediction by grabbing vital shooting information (such as the body of a player). The results suggest the athletes and coaches that if they want to improve the ability of prediction, it may be useful to shift their focus of attention from ball trajectory to body action.


Assuntos
Basquetebol , Desempenho Psicomotor , Humanos , Movimentos Oculares , Atletas , Sinais (Psicologia)
10.
Adv Sci (Weinh) ; 10(36): e2304905, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37897312

RESUMO

The asymmetrical growth of a single-wall carbon nanotube (SWCNT) by introducing a change of a local atomic structure, is usually inevitable and supposed to have a profound effect on the chirality control and property tailor. However, the breaking of the symmetry during SWCNT growth remains unexplored and its origins at the atomic-scale are elusive. Here, environmental transmission electron microscopy is used to capture the process of breaking the symmetry of a growing SWCNT from a sub-2-nm platinum catalyst nanoparticle in real-time, demonstrating that topological defects formed on the side of a SWCNT can serve as a buffer for stress release and inherently break its axis-symmetrical growth. Atomic-level details reveal the importance of the tube-catalyst interface and how the atom rearrangement of the solid-state platinum catalyst around the interface influences the final tubular structure. The active sites responsible for trapping carbon dimers and providing enough driving force for carbon incorporation and asymmetric growth are shown to be low-coordination step edges, as confirmed by theoretical simulations.

11.
JMIR Public Health Surveill ; 9: e47272, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37819703

RESUMO

BACKGROUND: As the SARS-CoV-2 attenuates and antibodies from the COVID-19 vaccine decline, long-term attention should be paid to the durability of primary booster administration and the preventive effect of the second or multiple booster doses of the COVID-19 vaccine. OBJECTIVE: This study aimed to explore the durability of primary booster administration and the preventive effect of second or multiple booster doses of the COVID-19 vaccine. METHODS: We established a bidirectional cohort in Guizhou Province, China. Eligible participants who had received the primary booster dose were enrolled for blood sample collection and administration of the second booster dose. A retrospective cohort for the time of administration was constructed to evaluate antibody attenuation 6-12 months after the primary booster dose, while a prospective cohort on the vaccine effect of the second booster dose was constructed for 4 months after the second administration. RESULTS: Between September 21, 2022, and January 30, 2023, a total of 327 participants were included in the final statistical analysis plan. The retrospective cohort revealed that approximately 6-12 months after receiving the primary booster, immunoglobulin G (IgG) slowly declined with time, while immunoglobulin A (IgA) remained almost constant. The prospective cohort showed that 28 days after receiving the second booster, the antibody levels were significantly improved. Higher levels of IgG and IgA were associated with better protection against COVID-19 infection for vaccine recipients. Regarding the protection of antibody levels against post-COVID-19 symptoms, the increase of the IgG had a protective effect on brain fog and sleep quality, while IgA had a protective effect on shortness of breath, brain fog, impaired coordination, and physical pain. CONCLUSIONS: The IgG and IgA produced by the second booster dose of COVID-19 vaccines can protect against SARS-CoV-2 infection and may alleviate some post-COVID-19 symptoms. Further data and studies on secondary booster administration are required to confirm these conclusions.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Estudos de Coortes , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Retrospectivos , Estudos Prospectivos , SARS-CoV-2 , Imunoglobulina A , Imunoglobulina G
12.
Nat Commun ; 14(1): 6467, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37833286

RESUMO

Herein, a metal-free electrochemical dihydroxylation of unactivated alkenes is described. The transformation proceeds smoothly under mild conditions with a broad range of unactivated alkenes, providing valuable and versatile dihydroxylated products in moderate to good yields without the addition of costly transition metals and stoichiometric amounts of chemical oxidants. Moreover, this method can be applied to a range of natural products and pharmaceutical derivatives, further demonstrating its synthetic utility. Mechanistic studies have revealed that iodohydrin and epoxide intermediate are formed during the reaction process.

13.
Huan Jing Ke Xue ; 44(10): 5823-5831, 2023 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-37827797

RESUMO

Applying organic fertilizer can increase the contents of soil organic carbon (SOC) and active organic carbon, which are crucial for strengthening soil quality and fertility. Four treatments were established:no fertilization (CK), single application of organic fertilizer (M), single application of chemical fertilizer (NPK), and combined application of organic and inorganic fertilizers (MNPK). The changes in SOC and active components under long-term combined application of organic and inorganic fertilizers were investigated, as were the effects of various fertilization measures on greenhouse gas emissions. Moreover, we evaluated the variation in the soil carbon pool management index (CPMI). Total organic carbon (TOC), microbial biomass carbon (MBC), dissolved organic carbon (DOC), easily oxidized organic carbon (EOC), and particulate organic carbon (POC) increased by 82.84%, 66.30%, 21.12%, 93.28%, and 145.80%, respectively, when compared to those in the CK treatment. The NPK treatment had no discernible effect on SOC and organic carbon components. The combined application of organic and inorganic materials could enhance LI, CPI, and the soil carbon pool management index, with the increase in LI and CPI being the primary reason for the increase in CPMI. Correlation analyses revealed that soil organic carbon components and CPMI were significantly positively correlated with greenhouse gas emissions. The combined application of organic and inorganic materials enhanced cumulative CO2 emissions and warming potential (GWP) but decreased GHGI and yielded a maximum of 56365 kg·hm-2. Compared with that in the CK treatment (29073 kg·hm-2), apple yield in MNPK increased by 93.87%. Therefore, applying organic and inorganic fertilizers in dryland apple orchards can improve the accumulation of organic carbon and stabilize the soil carbon pool, which is more beneficial to the sustainable development of orchards.

14.
Angew Chem Int Ed Engl ; 62(44): e202311941, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37708153

RESUMO

Herein, an electrochemically driven NiH-catalyzed reductive coupling of alkyl halides and alkyl alkenes for the construction of Csp3 -Csp3 bonds is firstly reported. Notably, alkyl halides serve dual function as coupling substrates and as hydrogen sources to generate NiH species under electrochemical conditions. The tunable nature of this reaction is realized by introducing an intramolecular coordinating group to the substrate, where the product can be easily adjusted to give the desired branched products. The method proceeds under mild conditions, exhibits a broad substrate scope, and affords moderate to excellent yields with over 70 examples, including late-stage modification of natural products and drug derivatives. Mechanistic insights offer evidence for an electrochemically driven coupling process. The sp3 -carbon-halogen bonds can be activated through single electron transfer (SET) by the nickel catalyst in its low valence state, generated by cathodic reduction, and the generation of NiH species from alkyl halides is pivotal to this transformation.

15.
J Am Chem Soc ; 145(40): 22232-22242, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37772932

RESUMO

N4-Acetylcytidine (ac4C) has been found to affect a variety of cellular and biological processes. For a mechanistic understanding of the roles of ac4C in biology and disease, we present an antibody-free, fluorine-assisted metabolic sequencing method to detect RNA ac4C, called "FAM-seq". We successfully applied FAM-seq to profile ac4C landscapes in human 293T, HeLa, and MDA cell lines in parallel with the reported acRIP-seq method. By comparison with the classic ac4C antibody sequencing method, we found that FAM-seq is a convenient and reliable method for transcriptome-wide mapping of ac4C. Because this method holds promise for detecting nascent RNA ac4C modifications, we further investigated the role of ac4C in regulating chemotherapy drug resistance in chronic myeloid leukemia. The results indicated that drug development or combination therapy could be enhanced by appreciating the key role of ac4C modification in cancer therapy.

16.
Angew Chem Int Ed Engl ; 62(45): e202312803, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37698174

RESUMO

Despite widespread use of the deuterium isotope effect, selective deuterium labeling of chemical molecules remains a major challenge. Herein, a facile and general electrochemically driven, organic mediator enabled deuteration of styrenes with deuterium oxide (D2 O) as the economical deuterium source was reported. Importantly, this transformation could be suitable for various electron rich styrenes mediated by triphenylphosphine (TPP). The reaction proceeded under mild conditions without transition-metal catalysts, affording the desired products in good yields with excellent D-incorporation (D-inc, up to >99 %). Mechanistic investigations by means of isotope labeling experiments and cyclic voltammetry tests provided sufficient support for this transformation. Notably, this method proved to be a powerful tool for late-stage deuteration of biorelevant compounds.

17.
Cell Transplant ; 32: 9636897231193069, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37615293

RESUMO

Human cord blood-endothelial progenitor cells (hCB-EPCs) isolated from the human umbilical cord can be used to repair damaged arteries. In this study, we used an animal model with pathological changes that mimics artery wall damage caused by stent retrievers in humans. We injected hCB-EPCs to investigate their effect on endothelial hyperplasia and dysfunction during intimal repair. Four groups were established based on the length of reperfusion (3 and 28 days), as well as the presence or absence of hCB-EPC therapy. Damage to the internal carotid artery was evaluated by hematoxylin-eosin and immunohistochemical staining. Stroke volume was not significantly different between non-EPC and EPC groups although EPC treatment alleviated intimal hyperplasia 28 days after intimal damage. Vascular endothelial growth factor (VEGF) and eNOS expression were significantly higher in the EPC-treated group than in the non-EPC group 3 days after intimal damage. In addition, MMP9 and 4HNE expression in the EPC-treated group was significantly lower than in the non-EPC group. Ultimately, this study found that venous transplantation of hCB-EPCs could inhibit neointimal hyperplasia, alleviate endothelial dysfunction, suppress intimal inflammation, and reduce oxidative stress during healing of intimal damage.


Assuntos
Células Progenitoras Endoteliais , Acidente Vascular Cerebral , Humanos , Ratos , Animais , Hiperplasia/metabolismo , Células Progenitoras Endoteliais/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Sangue Fetal , Artérias , Acidente Vascular Cerebral/terapia , Acidente Vascular Cerebral/metabolismo
18.
Environ Pollut ; 335: 122347, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37562528

RESUMO

The strict emission control measures have profoundly changed the air pollution in the Yangtze River Delta (YRD) region, China. However, the impacts of decreasing fine particulates (PM2.5) and nitrogen oxide (NOx) on summer ozone (O3) formation still remain disputable. We perform simulations in the 2018 summer over the YRD using the WRF-Chem model that considers the aerosol radiative forcing (ARF) and HO2 heterogeneous loss on aerosol surface. The model reasonably reproduces the measured spatiotemporal surface O3 and PM2.5 concentrations and aerosol compositions. Model sensitivity experiments show that the NOx mitigation during recent years changes daytime O3 formation in summer from the transition regime to the NOx-sensitive regime in the YRD. The decreasing NOx emission generally weakens O3 formation and lowers ambient O3 levels in summer during recent years, except for some urban centers of megacities. While, the haze alleviation characterized by a decline in ambient PM2.5 concentration in the past years largely counteracts the daytime O3 decrease caused by NOx mitigation, largely contributing to the persistently high levels of summertime O3. The counteracting effect is dominantly attributed to the attenuated ARF and minorly contributed by the suppressed HO2 uptake and heterogeneous loss on aerosol surface. These results highlight that the repeated O3 pollution in the YRD is closely associated with NOx and haze alleviation and more efforts must be taken to achieve lower O3 levels.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Ozônio/análise , Poluentes Atmosféricos/análise , Rios , Monitoramento Ambiental , Óxidos de Nitrogênio/análise , Óxido Nítrico , China , Poeira , Aerossóis/análise
19.
Front Cell Infect Microbiol ; 13: 1208473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520438

RESUMO

Introduction: Pantoea anthophila (P. anthophila) is a Gram-negative bacterium initially isolated from Impatiens balsamina in India. P. anthophila has been characterized with low pathogenicity, and no human infections caused by this organism have been reported yet. We report the first case of urinary tract infection caused by P. anthophila in a 73-year-old man after bladder cancer surgery. Methods: The bacterial isolate gained from urine was named UI705 and identified as P. anthophila by MALDI-TOF mass spectrometry. The genome sequencing and analysis were performed to further characterize the pathogenesis of the clinical isolate. Result and discussion: To the best of our knowledge, this is the first report of human infection caused by P. anthophila in China. The draft genome sequence of P. anthophila UI705 provides a fundamental resource for subsequent investigation of its virulence factors, antibiotic resistance, host-pathogen interactions, and comparative genomics of genus Pantoea.


Assuntos
Pantoea , Infecções Urinárias , Masculino , Humanos , Idoso , Pantoea/genética , Infecções Urinárias/microbiologia , Genômica , Sequência de Bases
20.
Life (Basel) ; 13(6)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37374080

RESUMO

The formose reaction is a plausible prebiotic chemistry, famed for its production of sugars. In this work, we demonstrate that the Cannizzaro process is the dominant process in the formose reaction under many different conditions, thus necessitating a catalyst for the formose reaction under various environmental circumstances. The investigated formose reactions produce primarily organic acids associated with metabolism, a protometabolic system, and yield very little sugar left over. This is due to many of the acids forming from the degradation and Cannizaro reactions of many of the sugars produced during the formose reaction. We also show the heterogeneous Lewis-acid-based catalysis of the formose reaction by mineral systems associated with serpentinization. The minerals that showed catalytic activity include olivine, serpentinite, and calcium, and magnesium minerals including dolomite, calcite, and our Ca/Mg-chemical gardens. In addition, computational studies were performed for the first step of the formose reaction to investigate the reaction of formaldehyde, to either form methanol and formic acid under a Cannizzaro reaction or to react to form glycolaldehyde. Here, we postulate that serpentinization is therefore the startup process necessary to kick off a simple proto metabolic system-the formose protometabolic system.

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