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1.
J Chromatogr A ; 1725: 464962, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38704923

RESUMO

Because of the "enterohepatic circulation" of bile acid, liver damage can be reflected by monitoring the content of bile acid in the serum of the organism. To monitor the concentration of 15 bile acids in plasma samples, a new technique of PRiME (process, ruggedness, improvement, matrix effect, ease of use) pass-through cleanup procedure combined with high performance liquid chromatography-tandem quadrupole mass spectrometry (HPLC-MS/MS) was developed. The sorbent used in the PRiME pass-through cleanup procedure is a new type of magnetic organic resin composite nano-material modified by C18 (C18-PS-DVB-GMA-Fe3O4), which has high cleanup efficiency of plasma samples. It also shows good performance in the separation and analysis of 15 kinds of bile acids. Under the optimal conditions, the results show higher cleanup efficiency of C18-PS-DVB-GMA-Fe3O4 with recoveries in the range of 82.1-115 %. The limit of quantitative (LOQs) of 15 bile acids were in the range of 0.033 µg/L-0.19 µg/L, and the RSD values of 15 bile acids were in the range of 3.00-11.9 %. Validation results on linearity, specificity, accuracy and precision, as well as on the application to analysis of 15 bile acids in 100 human plasma samples demonstrate the applicability to clinical studies.


Assuntos
Ácidos e Sais Biliares , Limite de Detecção , Nanocompostos , Espectrometria de Massas em Tandem , Humanos , Ácidos e Sais Biliares/sangue , Ácidos e Sais Biliares/química , Espectrometria de Massas em Tandem/métodos , Nanocompostos/química , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos Testes , Polímeros/química , Nanopartículas de Magnetita/química
2.
Natl Sci Rev ; 11(4): nwae063, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38623453

RESUMO

The Chinese Bayan Obo deposit is a world-class rare earth element (REE) deposit with considerable niobium (Nb) and iron (Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead (U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites-key Nb-bearing minerals-are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma (n = 99), 438 ± 7 Ma (n = 93), and 268 ± 5 Ma (n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

3.
Sci Adv ; 10(14): eadj8379, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579008

RESUMO

Magnetic tunnel junctions (MTJs) are the core element of spintronic devices. Currently, the mainstream writing operation of MTJs is based on electric current with high energy dissipation, and it can be notably reduced if an electric field is used instead. In this regard, it is promising for electric field control of MTJ in the multiferroic heterostructure composed of MTJ and ferroelectrics via strain-mediated magnetoelectric coupling. However, there are only reports on MTJs with in-plane anisotropy so far. Here, we investigate electric field control of the resistance state of MgO-based perpendicular MTJs with easy-cone anisotropic free layers through strain-mediated magnetoelectric coupling in multiferroic heterostructures. A remarkable, nonvolatile, and reversible modulation of resistance at room temperature is demonstrated. Through local reciprocal space mapping under different electric fields for Pb(Mg1/3Nb2/3)0.7Ti0.3O3 beneath the MTJ pillar, the modulation mechanism is deduced. Our work represents a crucial step toward electric field control of spintronic devices with non-in-plane magnetic anisotropy.

4.
Sci Adv ; 10(16): eadl4633, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640249

RESUMO

Magnetic tunnel junctions (MTJs) are the core elements of spintronic devices. Now, the mainstream writing operation of MTJs mainly relies on electric current with high energy dissipation, which can be greatly reduced if an electric field is used instead. In this regard, strain-mediated multiferroic heterostructure composed of MTJ and ferroelectrics are promising with the advantages of room temperature and magnetic field-free as already demonstrated by MTJ with in-plane magnetic anisotropy. However, there is no such report on the perpendicular MTJs (p-MTJs), which have been commercialized. Here, we investigate electric-field control of resistance state of MgO-based p-MTJs in multiferroic heterostructures. A remarkable and nonvolatile manipulation of resistance is demonstrated at room temperature without magnetic field assistance. Through various characterizations and micromagnetic simulation, the manipulation mechanism is uncovered. Our work provides an effective avenue for manipulating p-MTJ resistance by electric fields and is notable for high density and ultralow power spintronic devices.

5.
Molecules ; 29(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38474519

RESUMO

A series of NH2-functionalized nano-sized magnetic metal-organic frameworks (MOFs) were prepared in this study for Cr(VI) removal from wastewater. It was observed that not only the morphological, i.e., orientation growth of N-doped and iron-based metal-organic frameworks, but also the adsorption of magnetic MOFs is largely related to the used amount of ammonium hydroxide in preparation. For example, with increasing amounts of ammonium hydroxide used in preparation, the morphology of magnetic MOFs changed from spherical to cube and triangular cone. Moreover, the maximum adsorption capacity of spherical-magnetic MOFs, cubic-magnetic MOFs and triangular cone-magnetic MOFs could be up to 204.08 mg/g, 232.56 mg/g and 270.27 mg/g, respectively. Under optimal conditions, the adsorption process of magnetic MOFs for Cr(VI) was consistent with the pseudo-second-order rate equation (R2 = 1) and Langmuir isotherm model (R2 > 0.99). Therefore, magnetic MOFs developed in this work offered a viable option for the removal of Cr(VI) from wastewater.

6.
ACS Omega ; 9(11): 12676-12688, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38524470

RESUMO

Although oil and gas from coaly source rocks have been widely discovered worldwide, the role of oil generated from coal measures in marine-continental coaly deposits during the Carboniferous-Permian period in the Bohai Bay Basin has long been a subject of debate. The recent discovery of a condensate reservoir in the Wumaying buried hill within the Huanghua Depression of the Bohai Bay Basin offers new potential insights into this issue. In this study, we employed organic geochemical methods to explore the possibility of the Carboniferous-Permian coal deposit being a primary source of the condensate. The distribution of light hydrocarbons and the biomarker assemblage indicate that the condensate did not undergo significant secondary alterations such as thermal cracking, gas invasion fractionation, or biodegradation. The hydrocarbon generation potential of the Carboniferous-Permian coaly source rocks suggests that they could be an important contributor to the formation of condensate. High pristine/phytane ratios (1.0-7.5), an abundant presence of benzene series, and the dominance of C29 steranes (>50%) within the condensate could be indicative of coaly organic matter. These features are comparable to those found in coaly source rocks. Moreover, the stable carbon isotopic compositions of n-alkanes in the condensate, ranging from -26.0 to -30.0‰, correlate well with those from coaly mudstone (-25.4 to -30.0‰). This suggests that the condensate of the Wumaying buried hill may predominantly originate from the Carboniferous-Permian coaly mudstone. When integrated with the geological background, the results distinctly demonstrate that the Carboniferous-Permian coaly source rocks have significantly contributed to the formation of the condensate reservoir in the Wumaying buried hill. This provides an essential reference for future exploration of oil and gas resources derived from the carboniferous-Permian coaly source rocks in the Bohai Bay Basin.

7.
CNS Neurosci Ther ; 30(3): e14687, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38497517

RESUMO

AIMS: This study aimed to compare the clinical outcomes and safety of endovascular treatment (EVT) in patients with primary versus secondary medium vessel occlusion (MeVO). METHODS: From the endovascular treatment for acute ischemic stroke in the China registry, we collected consecutive patients with MeVO who received EVT. The primary endpoint was a good outcome, defined as a modified Rankin Scale (mRS) 0 to 2 at 90 days. RESULTS: 154 patients were enrolled in the final analysis, including 74 primary MeVO and 80 secondary MeVO. A good outcome at 90 days was achieved in 42 (56.8%) patients with primary MeVO and 33 (41.3%) patients with secondary MeVO. There was a higher probability of good outcomes in patients with the primary vs secondary MeVO (adjusted odds ratio, 2.16; 95% confidence interval, 1.04 to 4.46; p = 0.04). There were no significant differences in secondary and safety outcomes between MeVO groups. In the multivariable analysis, baseline ASPECTS (p = 0.001), final modified thrombolysis in cerebral infarction score (p = 0.01), and any ICH (p = 0.03) were significantly associated with good outcomes in primary MeVO patients, while baseline National Institutes of Health Stroke Scale (p = 0.002), groin puncture to recanalization time (p = 0.02), and early neurological improvement (p < 0.001) were factors associated with good outcome in secondary MeVO patients. CONCLUSION: In MeVO patients who received EVT, there was a higher likelihood of poor outcomes in patients with secondary versus primary MeVO.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Estados Unidos , Humanos , Acidente Vascular Cerebral/cirurgia , Acidente Vascular Cerebral/etiologia , Isquemia Encefálica/cirurgia , Isquemia Encefálica/etiologia , Resultado do Tratamento
8.
Pharmaceutics ; 16(1)2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38276519

RESUMO

The unique properties of ionic liquids (ILs), such as structural tunability, good solubility, chemical/thermal stability, favorable biocompatibility, and simplicity of preparation, have led to a wide range of applications in the pharmaceutical and biomedical fields. ILs can not only speed up the chemical reaction process, improve the yield, and reduce environmental pollution but also improve many problems in the field of medicine, such as the poor drug solubility, product crystal instability, poor biological activity, and low drug delivery efficiency. This paper presents a systematic and concise analysis of the recent advancements and further applications of ILs in the pharmaceutical field from the aspects of drug synthesis, drug analysis, drug solubilization, and drug crystal engineering. Additionally, it explores the biomedical field, covering aspects such as drug carriers, stabilization of proteins, antimicrobials, and bioactive ionic liquids.

9.
Eur J Mass Spectrom (Chichester) ; 30(1): 47-59, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37807771

RESUMO

To further understand the complexation and fragmentation during the extraction process, the formation of 2,9-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-12,4-benzotriazin-3-yl)-1,10-phenanthroline (CyMe4-BTPhen) complexes with lanthanides (Ln = La, Ce, Nd, Sm, Eu, Yb) and actinides (UO22+, Th4+) was observed by electrospray ionization mass spectrometry (ESI-MS) technique and density functional theory (DFT) calculations. Mass spectrometry titrations showed the variation relationship of different complexes in acetonitrile. For lanthanides, the major complexes were 1:2 species ([Ln(L)2]3+ and [Ln(L)2(NO3)]2+) with a ratio of 1:2, which were observed at the initial addition of Ln3+, whereas the species ([Ln(L)(NO3)2]+) with a ratio of 1:1 was detected when the [Ln]/[L] concentration ratio reached 1.0. For UO22+ and Th4+ complexes, 1:1 or 1:2 species ([UO2L(NO3)]+, Th(L)2(NO3)3+ and Th(L)2(NO3)22+) were formed. The fragmentation chemistry of both the ligand and the complex cations was characterized in detail by collision-induced dissociation. The fragmentation process of CyMe4-BTPhen was unfolded sequentially on both sides of the ligand by cleavage of C-C and C-N bonds. DFT calculations provided a detailed analysis of the structures and thermodynamics of those complexes, which indicated that the stable complexes formed in acetonitrile solution were consistent with the ESI-MS results.

10.
Methods ; 220: 106-114, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37972913

RESUMO

Discovering new indications for existing drugs is a promising development strategy at various stages of drug research and development. However, most of them complete their tasks by constructing a variety of heterogeneous networks without considering available higher-order connectivity patterns in heterogeneous biological information networks, which are believed to be useful for improving the accuracy of new drug discovering. To this end, we propose a computational-based model, called SFRLDDA, for drug-disease association prediction by using semantic graph and function similarity representation learning. Specifically, SFRLDDA first integrates a heterogeneous information network (HIN) by drug-disease, drug-protein, protein-disease associations, and their biological knowledge. Second, different representation learning strategies are applied to obtain the feature representations of drugs and diseases from different perspectives over semantic graph and function similarity graphs constructed, respectively. At last, a Random Forest classifier is incorporated by SFRLDDA to discover potential drug-disease associations (DDAs). Experimental results demonstrate that SFRLDDA yields a best performance when compared with other state-of-the-art models on three benchmark datasets. Moreover, case studies also indicate that the simultaneous consideration of semantic graph and function similarity of drugs and diseases in the HIN allows SFRLDDA to precisely predict DDAs in a more comprehensive manner.


Assuntos
Algoritmos , Semântica , Serviços de Informação
11.
Poult Sci ; 102(12): 103074, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37856909

RESUMO

This study aimed to investigate the association of insulin-like growth factor 1 receptor (IGF-1R) gene single nucleotide polymorphisms (SNPs) with growth traits and carcass traits of quail by PCR amplification and direct sequencing technology. Genomic DNA was extracted from blood samples collected from 49 female French Giant (FG) quails and 36 female Savimalt (SV) quails as part of this study. Growth traits and carcass traits were measured and assessed for IGF-1R gene analysis in the 2 meat-type quail strains. The results showed that 2 SNPs (A57G and A72T) of the IGF-1R gene were detected in the 2 quail strains. The A57G (P = 0.002) and A72T (P = 0.026) were significantly associated with breastbone length (BBL) in FG. Whereas A57G was significantly associated with chest weight (CW, P = 0.004), BBL (P = 0.009), and body length (BL, P = 0.009) in SV, while A72T was significantly associated with BBL (P = 0.014) and BL (P = 0.028) in SV. Haplotypes based on these 2 SNPs showed significant effects on BBL in FG strain (P = 0.000), and they also had significant effects on CW (P = 0.007), BBL (P = 0.004), and BL (P = 0.001) in SV strain. Additionally, A57G was significantly associated with liver rate (LR) in FG strain (P = 0.017). A72T showed significant associations with dressed carcass weight (DCW, P = 0.048) and breast muscle weight (BMW, P = 0.018) in FG strain. A57G was significantly associated with DCW (P = 0.048), whole net carcass weight (WNCW, P = 0.048), BMW (P = 0.036), and liver muscle rate (LMR, P = 0.003) in SV strain. Haplotypes also displayed significant effects on BMW (P = 0.029) and LMR (P = 0.010) in FG strain. These findings indicated that the IGF-1R gene could serve as a valuable molecular genetic marker for enhancing growth traits and carcass traits in meat-type quails.


Assuntos
Codorniz , Feminino , Animais , Codorniz/genética , Galinhas , Polimorfismo de Nucleotídeo Único , Carne/análise
12.
J Mass Spectrom ; 58(11): e4979, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37903512

RESUMO

Electrospray Ionization Mass Spectrometry (ESI-MS) technique and density functional theory (DFT) calculations were combined to study the formation of the complexes of lanthanides (Ln = La, Ce, Nd, Sm, Eu, Yb) and actinides (UO2 2+ , Th4+ ) with CyMe4 -BTBP (6,6'-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-benzo-[1,2,4-]triazin-3-yl)-[2,2']bipyridine) to understand the mechanisms during the extraction process. Mass spectrometry titrations showed the formation of the complexation in acetonitrile. For lanthanides, only 1:2 complexes ([Ln(L)2 ]3+ , [Ln(L)2 (CH3 CN)]3+ ), [Ln(L)2 (NO3 )]2+ ) were found at low [Ln]/[L] concentration ratios, whereas the 1:1 complexes ([Ln(L)(NO3 )2 ]+ ) were observed when the [Ln]/[L] concentration ratio reached 1.0. For uranyl complexes, 1:1 complex ([UO2 L(NO3 )]+ ) was the only species within the measuring range. Th4+ complexes had two compositions: 1:1 and 1:2, in which 1:2 species was the dominant complex. Collision-induced dissociation (CID) was employed to characterize the fragmentation process. The fragmentation process was unfolded sequentially on both sides of CyMe4 -BTBP ligand with the loss of alkyl groups and cleavage of triazinyl rings. The CID results of CyMe4 -BTBP complexes revealed a slight difference depending on the metal center. The DFT calculations showed that the stable complexes formed in acetonitrile solution were consistent with the ESI-MS results.

13.
Poult Sci ; 102(12): 103047, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37812872

RESUMO

The leptin receptor (LEPR) gene is a member of the class I cytokine receptor family, which plays an important role in weight regulation, fat accumulation and neuroendocrine function in animals. This study aimed to explore the association of single nucleotide polymorphisms (SNPs) of the LEPR gene with growth and carcass traits in meat-type quail by PCR amplification and DNA direct sequencing. In this study, genomic DNA was extracted from blood samples of 36 female Savimalt (SV) quails and 49 female French Giant (FG) quails. Growth traits (measured at 3 or 5 wk) and carcass traits (measured at 5 wk) were used for LEPR gene association analysis. The results showed the existence of 9 SNPs (T81C, G90T, C187A, A191G, A219G, G258A, C286T, G346A, and G373A) of the LEPR gene in the 2 quail strains. The statistical analyses indicated that these SNPs of LEPR gene was significantly associated with shank circumference (SC), shank length (SL), breastbone length (BBL), heart rate (HR), and whole net carcass rate (WNCR) of FG (P < 0.05); chest width (CW), body length (BL), leg muscle rate (LMR), whole net carcass rate (WNCR), and heart rate (HR) of SV (P < 0.05). While haplotypes showed significant effect on SL, BBL, heart weight (HW), WNCR, and HR of FG (P < 0.05). Therefore, the LEPR gene may serve as a molecular genetic marker for improving growth and carcass traits in quails.


Assuntos
Galinhas , Codorniz , Feminino , Animais , Codorniz/genética , Carne/análise , Polimorfismo de Nucleotídeo Único , DNA
14.
J Glob Antimicrob Resist ; 35: 149-158, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37709140

RESUMO

OBJECTIVES: The various sequence types (STs) of Pseudomonas aeruginosa (P. aeruginosa) high-risk clones (HiRiCs) have been sporadically reported in China, but the systematic analysis of genomes for these STs remains limited. This study aimed to address the evolutionary pathways underlying the emergence of HiRiCs and their routes of dissemination from Chinese and global perspectives. METHODS: The phylogenetic analysis was performed based on 416 newly sequenced clinical P. aeruginosa strains from Guangdong (GD), published genome sequences of 282 Chinese isolates, and 868 HiRiCs isolates from other countries. The genomic comparison study of global HiRiC ST244 was conducted to detect the model of global dissemination and local separation driven by association regional-specific antibiotic resistance genes. Furthermore, the evolutionary route of the emerging, China-specific HiRiC ST1971 was explored using Most Recent Common Ancestor (MRCA) analysis. RESULTS: Based on comparative genomics analysis, we found a clear geographical separation of ST244 isolates, yet with an association between ST244 isolates from GD and America. We identified a set of 38 AMR genes that contribute to the geographical separation in ST244, and we identified genetic determinants either positively (MexB) and negatively (opmD) associated with GD ST244. For the China-unique HiRiC ST1971, its evolutionary history across different continents before emerging as ST1971 in China was also deduced. CONCLUSION: This study provides insight into the specific genetics underlying regional differences among globally disseminated P. aeruginosa HiRiCs (ST244) as well as new understanding of the dissemination and evolution of a regional HiRiC (ST1971). Understanding the genetics of these and other HiRiCs may assist in controlling their emergence and further spread.


Assuntos
Antibacterianos , Pseudomonas aeruginosa , Filogenia , Antibacterianos/farmacologia , Genômica , China/epidemiologia
15.
Front Neurol ; 14: 1155269, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143999

RESUMO

Background and purpose: The first-pass recanalization of endovascular treatment (EVT) is closely correlated with clinical outcome of patients with large vessel occlusion (LVO) stroke. The aim of the study was to explore whether intra-arterial tenecteplase (TNK) during the first pass of EVT can increase first-pass successful reperfusion and improve the neurological outcome in AIS-LVO patients. Materials and methods: The BRETIS-TNK trial (ClinicalTrials.gov Identifier: NCT04202458) was a prospective, single-arm, single center study. Twenty-six eligible AIS-LVO patients with large-artery atherosclerosis etiology were consecutively enrolled from December 2019 to November 2021. Intra-arterial TNK (4 mg) after microcatheter navigation through the clot was administered, followed by TNK (0.4 mg/min) given continuously for 20 min after the first retrieval attempt of EVT without confirmation of the reperfusion status by DSA. The 50 control patients comprised of a historical cohort before the BRETIS-TNK trial (from March 2015 to November 2019). Successful reperfusion was defined as modified Thrombolysis In Cerebral Infarction (mTICI) ≥2b. Results: The first-pass successful reperfusion rate was higher in the BRETIS-TNK vs. control group (53.8% vs. 36%, p = 0.14), and the difference became statistically significant after propensity score matching (53.8% vs. 23.1%, p = 0.03). There was no difference in symptomatic intracranial hemorrhage between the BRETIS-TNK and control groups (7.7% vs. 10.0%, p = 0.92). There was a trend toward higher proportion of functional independence at 90 days in the BRETIS-TNK comparing with the control group (50% vs. 32%, p = 0.11). Conclusion: This is the first study to report that intra-arterial TNK during the first pass of EVT seems safe and feasible in AIS-LVO patients.

16.
Front Microbiol ; 14: 1117017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37125174

RESUMO

The ever-increasing prevalence of infections produced by multidrug-resistant or extensively drug-resistant Pseudomonas aeruginosa is commonly linked to a limited number of aptly-named epidemical 'high-risk clones' that are widespread among and within hospitals worldwide. The emergence of new potential high-risk clone strains in hospitals highlights the need to better and further understand the underlying genetic mechanisms for their emergence and success. P. aeruginosa related high-risk clones have been sporadically found in China, their genome sequences have rarely been described. Therefore, the large-scale sequencing of multidrug-resistance high-risk clone strains will help us to understand the emergence and transmission of antibiotic resistances in P. aeruginosa high-risk clones. In this study, 212 P. aeruginosa strains were isolated from 2 tertiary hospitals within 3 years (2018-2020) in Guangdong Province, China. Whole-genome sequencing, multi-locus sequence typing (MLST) and antimicrobial susceptibility testing were applied to analyze the genomic epidemiology of P. aeruginosa in this region. We found that up to 130 (61.32%) of the isolates were shown to be multidrug resistant, and 196 (92.45%) isolates were Carbapenem-Resistant Pseudomonas aeruginosa. MLST analysis demonstrated high diversity of sequence types, and 18 reported international high-risk clones were identified. Furthermore, we discovered the co-presence of exoU and exoS genes in 5 collected strains. This study enhances insight into the regional research of molecular epidemiology and antimicrobial resistance of P. aeruginosa in China. The high diversity of clone types and regional genome characteristics can serve as a theoretical reference for public health policies and help guide measures for the prevention and control of P. aeruginosa resistance.

17.
Int J Biol Macromol ; 242(Pt 3): 125043, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37224909

RESUMO

The investigation of interaction mechanism of U(VI) selective removal on amidoxime-functionalized metal organic framework (i.e., UiO-66(Zr)-AO) derived from macromolecular carbohydrate is conducive to apply metal organic frameworks in actual environmental remediation. The batch experiments showed that UiO-66(Zr)-AO displayed the fast removal rate (equilibrium time of 0.5 h), high adsorption capacity (384.6 mg/g), excellent regeneration performance (<10 % decrease after three cycles) towards U(VI) removal due to the unprecedented chemical stability, large surface area and simple fabrication. U(VI) removal at different pH can be satisfactorily fitted by diffuse layer modeling with cation exchange at low pH and an inner-sphere surface complexation at high pH. The inner-sphere surface complexation was further demonstrated by X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) analysis. These findings revealed that UiO-66(Zr)-AO can be an effective adsorbent to remove the radionuclides from aqueous solution, which is crucial for recycling of uranium resource and decreasing the uranium harm to the environment.


Assuntos
Estruturas Metalorgânicas , Urânio , Urânio/química , Porosidade , Adsorção
18.
Microbiol Spectr ; 11(3): e0426122, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37078855

RESUMO

Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is a bacterial pathogen that may cause serious drug-resistant infections that are potentially fatal. To investigate the genetic characteristics of these organisms, we tested 416 P. aeruginosa strains recovered from 12 types of clinical samples collected in 29 different hospital wards in 10 hospitals in Guangdong Province, China, from 2017 to 2020. These strains were found to belong to 149 known sequence types (STs) and 72 novel STs, indicating that transmission of these strains involved multiple routes. A high rate of resistance to imipenem (89.4%) and meropenem (79.4%) and a high prevalence of pathogenic serotypes (76.4%) were observed among these strains. Six STs of global high-risk clones (HiRiCs) and a novel HiRiC strains, ST1971, which exhibited extensive drug resistance, were identified. Importantly, ST1971 HiRiC, which was unique in China, also exhibited high virulence, which alarmed the further surveillance on this highly virulent and highly resistant clone. Inactivation of the oprD gene and overexpression of efflux systems were found to be mainly responsible for carbapenem resistance in these strains; carriage of metallo-ß-lactamase (MBL)-encoding genes was less common. Interestingly, frameshift mutations (49.0%) and introduction of a stop codon (22.4%) into the oprD genes were the major mechanisms of imipenem resistance. On the other hand, expression of the MexAB-OprM efflux pump and MBL-encoding genes were mechanisms of resistance in >70% of meropenem-resistant strains. The findings presented here provide insights into the development of effective strategies for control of worldwide dissemination of CRPA. IMPORTANCE Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is a major concern in clinical settings worldwide, yet few genetic and epidemiological studies on CRPA strains have been performed in China. Here, we sequence and analyze the genomes of 416 P. aeruginosa strains from hospitals in China to elucidate the genetic, phenotypic, and transmission characteristics of CRPA strains and to identify the molecular signatures responsible for the observed increase in the prevalence of CRPA infections in China. These findings may provide new insight into the development of effective strategies for worldwide control of CRPA and minimize the occurrence of untreatable infections in clinical settings.


Assuntos
Antibacterianos , Infecções por Pseudomonas , Humanos , Meropeném/farmacologia , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Carbapenêmicos/farmacologia , Carbapenêmicos/metabolismo , Pseudomonas aeruginosa , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Imipenem/farmacologia , Imipenem/metabolismo , beta-Lactamases/genética , beta-Lactamases/metabolismo , Testes de Sensibilidade Microbiana
19.
Biomater Sci ; 11(11): 3878-3892, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37078909

RESUMO

An artificial periosteum has emerged as an encouraging candidate for bone defect repair. Currently, it remains a great challenge to develop a multifaceted biomimetic periosteum integrating multifunctional features of bioactivities and unique mechanical properties. Here, we successfully fabricated an artificial periosteum (AP) composed of hierarchically assembled Mg-doped mineralized collagen microfibrils with a biomimetically rotated lamellar structure via a "multiscale cascade regulation" strategy combining multiple techniques such as molecular self-assembly, electrospinning, and pressure-driven fusion from molecular to macroscopic levels. The AP has excellent mechanical properties with an ultimate strength and a tensile modulus of 15.9 MPa and 1.1 GPa, respectively. The involvement of Mg-doped nano-hydroxyapatite endowed the AP with good osteogenic and angiogenic activities to promote osteogenic differentiation of bone marrow mesenchymal stem cells and human umbilical vein endothelial cell differentiation into capillary-like structures in vitro. In addition, the results of in vivo evaluations in a rat cranial bone defect model including micro-CT morphology, histological staining, and immunohistochemical analysis showed that Mg-doped mineralized collagen-based AP (MgMC@AP) significantly facilitated cranial bone regeneration and fast vascularization. Our findings suggest that the AP mimicked the composition, lamellar structure, mechanical properties, and biological activities of natural periosteum/lamellae, showing great promise for bone tissue regeneration.


Assuntos
Osteogênese , Periósteo , Ratos , Animais , Humanos , Periósteo/química , Alicerces Teciduais/química , Biomimética , Regeneração Óssea , Colágeno , Crânio , Engenharia Tecidual/métodos
20.
J Phys Condens Matter ; 35(30)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37102208

RESUMO

Fe-based superconductors are one of the current research focuses. FeTe is unique in the series of FeSe1-xTex, since it is nonsuperconducting near the FeTe side in the phase diagram in contrast to the presence of superconductivity in other region. However, FeTe thin films become superconducting after oxygen annealing and the mechanism remains elusive. Here, we report the temperature dependences of resistivity, Hall effect and magnetoresistance (MR) of a series of FeTe thin films with different amounts of excess Fe and oxygen. These properties show dramatic changes with excess Fe and oxygen incorporation. We found the Hall coefficients are positive for the oxygen-annealed samples, in contrast to the transition from positive to negative below 50 K for the vacuum-annealed samples. For all samples, both the resistivity and Hall coefficient show a dramatic drop, respectively, at around 50 K-75 K, implying coexistence of superconductivity and antiferromagnetic order for the oxygen-annealed samples. The vacuum-annealed samples show both positive and negative values of MR depending on temperature, while negative MR dominates for the oxygen-annealed samples. We also found that oxygen annealing reduces the excess Fe in FeTe, which has been neglected before. The results are discussed in terms of several contributions, and a comparison is made between the oxygen-annealed FeTe thin films and FeSe1-xTex. This work is helpful for shedding light on the understanding of oxygen-annealed FeTe thin films.

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