-
Journal of Agricultural and Food... Jun 2024Flupyradifurone (FPF) is considered the latest generation of neonicotinoid insecticides. Here, we investigated the toxicity and ecological risk of FPF and its aerobic...
Flupyradifurone (FPF) is considered the latest generation of neonicotinoid insecticides. Here, we investigated the toxicity and ecological risk of FPF and its aerobic transformation products (TPs) to aquatic species using the method of prediction. We found that FPF exhibited moderate or high toxicity to some aquatic species. The 5% hazardous concentration of FPF was 3.84 μg/L for aquatic organisms. We obtained 91 aerobic TPs for FPF, and almost half of FPF TPs exhibited toxicity to fish or . Eleven of the TPs of FPF exhibited a high or moderate risk to aquatic ecosystems. All FPF TPs with high and moderate risks contained a 6-chloropyridine ring structure, indicating that the derivant of a pyridine ring exhibits potential risks to aquatic ecosystems. Our results provide insight into the potential risk of FPF to aquatic ecosystems and could be used to help set criteria to control pollution caused by FPF.
PubMed: 38941616
DOI: 10.1021/acs.jafc.4c03004 -
The Journal of Physical Chemistry... Jun 2024The gas phase protonation sites of six naturally occurring nicotinoids, namely nicotine (NIC), nornicotine (NOR), anabasine (ANB), anatabine (ANT), cotinine (COT), and...
The gas phase protonation sites of six naturally occurring nicotinoids, namely nicotine (NIC), nornicotine (NOR), anabasine (ANB), anatabine (ANT), cotinine (COT), and myosmine (MYO), consisting of a common Pyridine and differing -Pyridine rings, have been determined for the first time at the physiological temperature from cryogenic ion trap infrared spectroscopy and electronic structure calculations. The protonation site on either of these two rings is related to the nicotinoid's biological activity. At room temperature, NIC is a mixture of Pyridine and Pyrrolidine (-Pyridine) protomers, whereas NOR, ANB, ANT, and COT are pure Pyridine protomers and finally MYO is mostly a Pyroline (-Pyridine) protomer. The nearly planar structure of MYO-H, induced by the presence of a conjugated π system and confirmed from calculations and the UV absorption spectra, breaks from the trends observed for NIC, NOR, and ANB, since its structure is drastically different from the structures of the other nicotinoids.
PubMed: 38940770
DOI: 10.1021/acs.jpclett.4c01206 -
ChemPlusChem Jun 2024The new ligand 3,3'-bis(((2-(3,6,9-triaza-1(2,6)-pyridinacyclodecaphane-6-yl)ethyl)amino)methyl)-[1,1'-biphenyl]-2,2'-diol (L) has been synthesized and characterized. It...
The new ligand 3,3'-bis(((2-(3,6,9-triaza-1(2,6)-pyridinacyclodecaphane-6-yl)ethyl)amino)methyl)-[1,1'-biphenyl]-2,2'-diol (L) has been synthesized and characterized. It contains two pyridinacyclophane macrocycles spaced by a 2,2'-biphenol moiety. The acid-base behaviour of L as well as its binding properties towards Zn2+ ion have been investigated. This work is inserted in the field of fluorescent ditopic receptors, formed by two polyamines spaced by a aromatic fragments. This ligand represents a new example of a peculiar case of polyamine fluorescent receptor in which the interaction with Zn2+ is translated into a deactivation of the emission. Enough data to describe and explain this unusual behaviour was obtained through potentiometric, UV-Vis, fluorescence and NMR titrations as well as theoretical calculations. This studies have shown that the metal cation is indirectly affecting the emission favouring a conformation in which the fluorophore is at stacking distance from the electron poor pyridine moieties. This gives rise to an oxidative photoinduced electron transfer from the excited state of the fluorophore to the electron-poor Zn2+ coordined pyridine.
PubMed: 38940317
DOI: 10.1002/cplu.202400342 -
G-quadruplex-guided cisplatin triggers multiple pathways in targeted chemotherapy and immunotherapy.Chemical Science Jun 2024G-quadruplexes (G4s) are atypical nucleic acid structures involved in basic human biological processes and are regulated by small molecules. To date, pyridostatin and...
G-quadruplexes (G4s) are atypical nucleic acid structures involved in basic human biological processes and are regulated by small molecules. To date, pyridostatin and its derivatives [, PyPDS (4-(2-aminoethoxy)- , -bis(4-(2-(pyrrolidin-1-yl) ethoxy) quinolin-2-yl) pyridine-2,6-dicarboxamide)] are the most widely used G4-binding small molecules and considered to have the best G4 specificity, which provides a new option for the development of cisplatin-binding DNA. By combining PyPDS with cisplatin and its analogs, we synthesize three platinum complexes, named PyPDSplatins. We found that cisplatin with PyPDS (CP) exhibits stronger specificity for covalent binding to G4 domains even in the presence of large amounts of dsDNA compared with PyPDS either extracellularly or intracellularly. Multiomics analysis reveals that CP can effectively regulate G4 functions, directly damage G4 structures, activate multiple antitumor signaling pathways, including the typical cGAS-STING pathway and AIM2-ASC pathway, trigger a strong immune response and lead to potent antitumor effects. These findings reflect that cisplatin-conjugated specific G4 targeting groups have antitumor mechanisms different from those of classic cisplatin and provide new strategies for the antitumor immunity of metals.
PubMed: 38939132
DOI: 10.1039/d4sc00643g -
Organometallics Jun 2024A series of U(IV) complexes bearing alkyl and chloride ligands in the configuration was synthesized and characterized. Starting with the diastereopure U(IV) -dichloride...
A series of U(IV) complexes bearing alkyl and chloride ligands in the configuration was synthesized and characterized. Starting with the diastereopure U(IV) -dichloride complex -( ONO)UCl(dtbpy) (, ONO = 2,6-bis((di--butylphosphino)methanolato)pyridine), four distinct alkyl groups were employed to prepare ( ONO)U(R)Cl(dtbpy), where R = (trimethylsilyl)methyl (neosilyl), , R = 2,2-dimethyl propyl (neopentyl), , and R = 2-methyl-2-phenyl propyl (neophyl), . Alkylation occurs with specificity but generates a predominant species and a minor species corresponding to / regioisomers relative to the P groups of the ligand. For synthesis using R = methyl, the dimethyl complex ( ONO)U(Me)(dtbpy), , was prepared; the addition of 1 equiv of MeLi produced a mixture of products. Complexes - were characterized using single crystal X-ray diffraction (SC-XRD), UV-vis-nIR, and H and P NMR spectroscopies.
PubMed: 38938898
DOI: 10.1021/acs.organomet.4c00069 -
JACS Au Jun 2024Chalcogen bonding interactions (ChBIs) have been widely employed to create ordered noncovalent assemblies in solids and liquids. Yet, their ability to engineer molecular...
Chalcogen bonding interactions (ChBIs) have been widely employed to create ordered noncovalent assemblies in solids and liquids. Yet, their ability to engineer molecular self-assembly on surfaces has not been demonstrated. Here, we report the first demonstration of on-surface molecular recognition solely governed by ChBIs. Scanning tunneling microscopy and calculations reveal that a pyrenyl derivative can undergo noncovalent chiral dimerization on the Au(111) surface through double Ch···N interactions involving Te- or Se-containing chalcogenazolo pyridine motifs. In contrast, reference chalcogenazole counterparts lacking the pyridyl moiety fail to form regular self-assemblies on Au, resulting in disordered assemblies.
PubMed: 38938818
DOI: 10.1021/jacsau.4c00325 -
Analytical Chemistry Jun 2024Breath analysis with secondary electrospray ionization (SESI) coupled to mass spectrometry (MS) is a sensitive method for breath metabolomics. To enable quantitative...
Breath analysis with secondary electrospray ionization (SESI) coupled to mass spectrometry (MS) is a sensitive method for breath metabolomics. To enable quantitative assessments using SESI-MS, a system was developed to introduce controlled amounts of gases into breath samples and carry out standard addition experiments. The system combines gas standard generation through controlled evaporation, humidification, breath dilution, and standard injection with the help of mass-flow controllers. The system can also dilute breath, which affects the signal of the detected components. This response can be used to filter out contaminating compounds in an untargeted metabolomics workflow. The system's quantitative capabilities have been shown through standard addition of pyridine and butyric acid into breath in real time. This system can improve the quality and robustness of breath data.
PubMed: 38937865
DOI: 10.1021/acs.analchem.4c01924 -
Journal of Cardiothoracic Surgery Jun 2024Thoracic endovascular aortic repair (TEVAR) is a minimally invasive technique used to treat type B aortic dissections. Left subclavian artery (LSA) reconstruction is...
BACKGROUND
Thoracic endovascular aortic repair (TEVAR) is a minimally invasive technique used to treat type B aortic dissections. Left subclavian artery (LSA) reconstruction is required when treating patients with involvement of LSA. The best antiplatelet therapy after LSA reconstruction is presently uncertain.
METHODS
This study retrospectively analyzed 245 type B aortic dissection patients who underwent left subclavian artery revascularization during TEVAR. Out of 245 patients, 159 (64.9%) were in the single antiplatelet therapy (SAPT) group, receiving only aspirin, and 86 (35.1%) were in the dual antiplatelet therapy (DAPT) group, receiving aspirin combined with clopidogrel. During the 6-month follow-up, primary endpoints included hemorrhagic events (general bleeding and hemorrhagic strokes), while secondary endpoints comprised ischemic events (left upper limb ischemia, ischemic stroke, and thrombotic events), as well as death and leakage events. Both univariate and multivariate Cox regression analyses were performed on hemorrhagic and ischemic events, with the Kaplan-Meier method used to generate the survival curve.
RESULTS
During the six-month follow-up, the incidence of hemorrhagic events in the DAPT group was higher (8.2% vs. 30.2%, P < 0.001). No significant differences were observed in ischemic events, death, or leakage events among the different antiplatelet treatment schemes. Multivariate Cox regression analysis showed that DAPT (HR: 2.22, 95% CI: 1.07-4.60, P = 0.032) and previous chronic conditions (HR:3.88, 95% CI: 1.24-12.14, P = 0.020) significantly affected the occurrence of hemorrhagic events. Chronic conditions in this study encompassed depression, vitiligo, and cholecystolithiasis. Carotid subclavian bypass (CSB) group (HR:0.29, 95% CI: 0.12-0.68, P = 0.004) and single-branched stent graft (SBSG) group (HR:0.26, 95% CI: 0.13-0.50, P < 0.001) had a lower rate of ischemic events than fenestration TEVAR (F-TEVAR). Survival analysis over 6 months revealed a lower risk of bleeding associated with SAPT during hemorrhagic events (P = 0.043).
CONCLUSIONS
In type B aortic dissection patients undergoing LSA blood flow reconstruction after synchronous TEVAR, the bleeding risk significantly decreases with the SAPT regimen, and there is no apparent ischemic compensation within 6 months. Patients with previous chronic conditions have a higher risk of bleeding. The CSB group and SBSG group have less ischemic risk compared to F-TEVAR group.
Topics: Humans; Male; Female; Retrospective Studies; Platelet Aggregation Inhibitors; Subclavian Artery; Middle Aged; Aortic Dissection; Endovascular Procedures; Aortic Aneurysm, Thoracic; Aged; Clopidogrel; Aspirin; Aorta, Thoracic; Treatment Outcome; Blood Vessel Prosthesis Implantation; Postoperative Complications; Endovascular Aneurysm Repair
PubMed: 38937841
DOI: 10.1186/s13019-024-02932-3 -
Nature Chemistry Jun 2024Catalytic processes are largely dominated by transition-metal complexes. Main-group compounds that can mimic the behaviour of the transition-metal complexes are of great...
Catalytic processes are largely dominated by transition-metal complexes. Main-group compounds that can mimic the behaviour of the transition-metal complexes are of great interest due to their potential to substitute or complement transition metals in catalysis. While a few main-group molecular centres were shown to activate dihydrogen via the oxidative addition process, catalytic hydrogenation using these species has remained challenging. Here we report the synthesis, isolation and full characterization of the geometrically constrained phosphenium cation with the 2,6-bis(o-carborano)pyridine pincer-type ligand. Notably, this cation can activate the H-H bond by oxidative addition to a single P cationic centre, producing a dihydrophosphonium cation. This phosphenium cation is also capable of catalysing hydrogenation reactions of C=C double bonds and fused aromatic systems, making it a main-group compound that can both activate H at a single molecular main-group centre and be used for catalytic hydrogenation. This finding shows the potential of main-group compounds, in particular phosphorus-based compounds, to serve as metallomimetic hydrogenation catalysts.
PubMed: 38937592
DOI: 10.1038/s41557-024-01569-y -
Scientific Reports Jun 2024Delayed cerebral ischemia (DCI) after aneurysmal subarachnoid haemorrhage (aSAH) is a singular pathological entity necessitating early diagnostic approaches and both...
Delayed cerebral ischemia (DCI) after aneurysmal subarachnoid haemorrhage (aSAH) is a singular pathological entity necessitating early diagnostic approaches and both prophylactic and curative interventions. This retrospective before-after study investigates the effects of a management strategy integrating perfusion computed tomography (CTP), vigilant clinical monitoring and standardized systemic administration of milrinone on the occurrence of delayed cerebral infarction (DCIn). The period included 277 patients, and the one 453. There was a higher prevalence of Modified Fisher score III/IV and more frequent diagnosis of vasospasm in the period. Conversely, the occurrence of DCIn was reduced with the management strategy (adjusted OR 0.48, 95% CI [0.26; 0.84]). Notably, delayed ischemic neurologic deficits were less prevalent at the time of vasospasm diagnosis (24 vs 11%, ), suggesting that CTP facilitated early detection. In patients diagnosed with vasospasm, intravenous milrinone was more frequently administered (80 vs 54%, ) and associated with superior hemodynamics. The present study from a large cohort of aSAH patients suggests, for one part, the interest of CTP in early diagnosis of vasospasm and DCI, and for the other the efficacy of CT perfusion-guided systemic administration of milrinone in both preventing and treating DCIn.
Topics: Humans; Subarachnoid Hemorrhage; Milrinone; Male; Female; Middle Aged; Cerebral Infarction; Retrospective Studies; Tomography, X-Ray Computed; Aged; Vasospasm, Intracranial; Adult; Administration, Intravenous
PubMed: 38937568
DOI: 10.1038/s41598-024-65706-w