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1.
Aesthetic Plast Surg ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849551

RESUMO

BACKGROUND: Recipient-area perifollicular erythema (RPE) may delay graft growth after hair transplantation. However, there is currently a lack of observational clinical studies of RPE. OBJECTIVE: To study the clinical features and risk factors associated with RPE while analyzing its correlation with graft growth. METHODS: We conducted a multicenter retrospective cohort study between June 2020 and January 2023. RESULTS: A total of 1090 participants were included, 178 (16.33%) showed mild RPE, 56 (5.14%) showed moderate RPE, and 10 (0.92%) showed severe RPE. Patients with RPE had severe hair shaft shedding (P < 0.001) and a lower survival rate (P < 0.001) of grafts. Logistic regression analysis showed that folliculitis is a significant risk factor for mild RPE (OR 6.061, 95% CI 3.343-10.991, P < 0.001) and moderate RPE (OR 3.397, 95% CI 1.299-8.882, P = 0.013). Besides, untimely first postoperative hair washing was associated with the development of moderate RPE (OR 0.724, 95% CI 0.553-0.947, P = 0.018) and severe RPE (OR 1.553, 95% CI 1.156-2.086, P = 0.003). CONCLUSION: RPE is a postoperative complication closely related to high hair shaft shedding proportion and low graft survival rate. Both postoperative folliculitis and untimely first postoperative hair washing may induce the occurrence of RPE. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

2.
J Colloid Interface Sci ; 673: 616-627, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38897063

RESUMO

Oxygen evolution reaction (OER) is the efficiency limiting half-reaction in water electrolysis for green hydrogen production due to the 4-electron multistep process with sluggish kinetics. The electrooxidation of thermodynamically more favorable organics accompanied by CC coupling is a promising way to synthesize value-added chemicals instead of OER. Efficient catalyst is of paramount importance to fulfill such a goal. Herein, a molybdenum iron carbide-copper hybrid (Mo2C-FeCu) was designed as anodic catalyst, which demonstrated decent OER catalytic capability with low overpotential of 238 mV at response current density of 10 mA cm-2 and fine stability. More importantly, the Mo2C-FeCu enabled electrooxidation assisted aldol condensation of phenylcarbinol with α-H containing alcohol/ketone in weak alkali electrolyte to selective synthesize cinnamaldehyde/benzalacetone at reduced potential. The hydroxyl and superoxide intermediate radicals generated at high potential are deemed to be responsible for the electrooxidation of phenylcarbinol and aldol condensation reactions to afford cinnamaldehyde/benzalacetone. The current work showcases an electrochemical-chemical combined CC coupling reaction to prepare organic chemicals, we believe more widespread organics can be synthesized by tailored electrochemical reactions.

3.
J Med Virol ; 96(5): e29650, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38727133

RESUMO

To analyze the epidemiological characteristics of group A rotavirus (RVA) diarrhea in Beijing between 2019 and 2022 and evaluate the effectiveness of the RV5 vaccine. Stool specimens were collected from patients with acute diarrhea, and RVA was detected and genotyped. The whole genome of RVA was sequenced by fragment amplification and Sanger sequencing. Phylogenetic trees were constructed using Bayesian and maximum likelihood methods. Descriptive epidemiological methods were used to analyze the characteristics of RVA diarrhea. Test-negative design was used to evaluate the vaccine effectiveness (VE) of the RV5. Compared with 2011-2018, RVA-positive rates in patients with acute diarrhea under 5 years of age and adults decreased significantly between 2019 and 2022, to 9.45% (249/634) and 3.66% (220/6016), respectively. The predominant genotype of RVA had changed from G9-VIP[8]-III between 2019 and 2021 to G8-VP[8]-III in 2022, and P[8] sequences from G8-VP[8]-III strains formed a new branch called P[8]-IIIb. The complete genotype of G8-VP[8]-III was G8-P[8]-I2-R2-C2-M2-A2-N2-T2-E2-H2. The VE of 3 doses of RV5 was 90.4% (95% CI: 28.8%-98.7%) against RVA diarrhea. The prevalence of RVA decreased in Beijing between 2019 and 2022, and the predominant genotype changed to G8P[8], which may be related to RV5 vaccination. Continuous surveillance is necessary to evaluate vaccine effectiveness and improve vaccine design.


Assuntos
Diarreia , Fezes , Genótipo , Filogenia , Infecções por Rotavirus , Vacinas contra Rotavirus , Rotavirus , Humanos , Rotavirus/genética , Rotavirus/classificação , Rotavirus/imunologia , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Infecções por Rotavirus/prevenção & controle , Diarreia/virologia , Diarreia/epidemiologia , Vacinas contra Rotavirus/administração & dosagem , Vacinas contra Rotavirus/imunologia , Pré-Escolar , Prevalência , Pequim/epidemiologia , Masculino , Lactente , Feminino , Adulto , Fezes/virologia , Pessoa de Meia-Idade , Criança , Adulto Jovem , Adolescente , Eficácia de Vacinas , Idoso , Genoma Viral , Recém-Nascido
4.
Angew Chem Int Ed Engl ; 63(23): e202403464, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38581155

RESUMO

Herein, two atomically precise silver nanoclusters, Ag54 and Ag33, directed by inner anion templates (CrO4 2- and/or Cl-), are initially isolated as a mixed phase from identical reactants across a wide temperature range (20-80 °C). Interestingly, fine-tuning the reaction temperature can realize pure phase synthesis of the two nanoclusters; that is, a metastable Ag54 is kinetically formed at a low temperature (20 °C), whereas such a system is steered towards a thermodynamically stable Ag33 at a relatively high temperature (80 °C). Electrospray ionization mass spectrometry illustrates that the stability of Ag33 is superior to that of Ag54, which is further supported by density functional theory calculations. Importantly, the difference in structural stability can influence the pathway of 1,4-bis(pyrid-4-yl)benzene induced transformation reaction starting from Ag54 and Ag33. The former undergoes a dramatic breakage-reorganization process to form an Ag31 dimer (Ag31), while the same product can be also achieved from the latter following a noninvasive ligand exchange process. Both the Ag54 and Ag33 have the potential for further remote laser ignition applications. This work not only demonstrates how temperature controls the isolation of a specific phase, but also sheds light on the structural transformation pathway of nanoclusters with different stability.

5.
J Am Chem Soc ; 146(15): 10767-10775, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38591723

RESUMO

Atomically precise superatomic copper nanoclusters (Cu NCs) have been the subject of immense interest for their intriguing structures and diverse properties; nonetheless, the variable oxidation state of copper ions and complex solvation effects in wet synthesis systems pose significant challenges for comprehending their synthesis and crystallization mechanism. Herein, we present a solvent-mediated approach for the synthesis of two Cu NCs, namely, superatomic Cu26 and pure-Cu(I) Cu16. They initially formed as a hetero-phase and then separated as a homo-phase via modulating binary solvent composition. In situ UV/vis absorption and electrospray ionization mass spectra revealed that the solvent-mediated assembly was determined to be the underlying mechanism of hetero/homo-phase crystallization. Cu26 is a 2-electron superatom with a kernel-shell structure that includes a [Cu20Se12]4- shell and [Cu6]4+ kernel, containing two 1S jellium electrons. Conversely, Cu16 is a pure-Cu(I) Cu/Se nanocluster that features a [Cu16Se6]4+ core protected by extra dimercaptomaleonitrile ligands. Remarkably, Cu26 exhibits unique near-infrared phosphorescence (NIR PH) at 933 nm due to the presence of a superatomic kernel-related charge transfer state (3MM(Cu)CT). Overall, this work not only showcases the hetero/homo-phase crystallization of Cu NCs driven by a solvent-mediated assembly mechanism but also enables the rare occurrence of NIR PH within the 2-electron copper superatom family.

6.
J Colloid Interface Sci ; 665: 152-162, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38520932

RESUMO

H2 and formate are important energy carriers in fuel-cells and feedstocks in chemical industry. The hydrogen evolution reaction (HER) coupling with electro-oxidative cleavage of thermodynamically favorable polyols is a promising way to coproduce H2 and formate via electrochemical means, highly active catalysts for HER and electrooxidative cleavage of polycols are the key to achieve such a goal. Herein, molybdenum (Mo), tungsten (W) doped cobalt phosphides (Co2P) deposited onto nickel foam (NF) substrate, denoted as Mo-Co2P/NF and W-Co2P/NF, respectively, were investigated as catalytic electrodes for HER and electrochemical glycerol oxidation reaction (GOR) to yield H2 and formate. The W-Co2P/NF electrode exhibited low overpotential (η) of 113 mV to attain a current density (J) of -100 mA cm-2 for HER, while the Mo-Co2P/NF electrode demonstrated high GOR efficiency for selective production of formate. In situ Raman and infrared spectroscopic characterizations revealed that the evolved CoO2 from Co2P is the genuine catalytic sites for GOR. The asymmetric electrolyzer based on W-Co2P/NF cathode and Mo-Co2P/NF anode delivered a J = 100 mA cm-2 at 1.8 V voltage for glycerol electrolysis, which led to 18.2 % reduced electricity consumption relative to water electrolysis. This work highlights the potential of heteroelement doped phosphide in catalytic performances for HER and GOR, and opens up new avenue to coproduce more widespread commodity chemicals via gentle and sustainable electrocatalytic means.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38376963

RESUMO

Video compression is indispensable to most video analysis systems. Despite saving the transportation bandwidth, it also deteriorates downstream video understanding tasks, especially at low-bitrate settings. To systematically investigate this problem, we first thoroughly review the previous methods, revealing that three principles, i.e., task-decoupled, label-free, and data-emerged semantic prior, are critical to a machine-friendly coding framework but are not fully satisfied so far. In this paper, we propose a traditional-neural mixed coding framework that simultaneously fulfills all these principles, by taking advantage of both traditional codecs and neural networks (NNs). On one hand, the traditional codecs can efficiently encode the pixel signal of videos but may distort the semantic information. On the other hand, highly non-linear NNs are proficient in condensing video semantics into a compact representation. The framework is optimized by ensuring that a transportation-efficient semantic representation of the video is preserved w.r.t. the coding procedure, which is spontaneously learned from unlabeled data in a self-supervised manner. The videos collaboratively decoded from two streams (codec and NN) are of rich semantics, as well as visually photo-realistic, empirically boosting several mainstream downstream video analysis task performances without any post-adaptation procedure. Furthermore, by introducing the attention mechanism and adaptive modeling scheme, the video semantic modeling ability of our approach is further enhanced. Fianlly, we build a low-bitrate video understanding benchmark with three downstream tasks on eight datasets, demonstrating the notable superiority of our approach. All codes, data, and models will be open-sourced for facilitating future research.

8.
Gene ; 906: 148256, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38341003

RESUMO

Nucleotide-binding sites and leucine-rich repeat proteins (NLRs) act as critical intracellular immune receptors. Previous studies reported an Arabidopsis-resistant gene L3 (AT1G15890), which encoded a coiled-coil (CC) NLR that conferred cell death in bacteria; however, its function in planta remains unclear. This study describes a comprehensive structure-function analysis of L3 in Nicotiana benthamiana. The results of the transient assay showed that the L3 CC domain is sufficient for cell-death induction. The first 140 amino acid segment constituted the minimal function region that could cause cell death. The YFP-labeled L3 CC domain was localized to the plasma membrane, which was considered crucial for the function and self-interaction of the L3 CC domain. The results of point mutations analysis showed that L3 CC domain function is affected by mutations in some specific residues, and loss-of-function mutations in the CC domain affected the function of full-length L3. These study results offered considerable evidence to understand the activation mechanism of L3.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Nicotiana/genética , Sequência de Aminoácidos , Expressão Ectópica do Gene , Proteínas de Transporte/genética , Proteínas de Arabidopsis/metabolismo , Morte Celular/genética , Doenças das Plantas/genética , Proteínas de Plantas/metabolismo
9.
Viruses ; 16(1)2024 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-38275961

RESUMO

Norovirus (NoV) is a major cause of acute gastroenteritis outbreaks worldwide. A comprehensive understanding of the transmission mode is of great significance for the prevention and control of the NoV infection. Currently, the transmission modes of NoV include contact, food-borne, water-borne and aerosol transmission. The first three modes are more common, while aerosol transmission is seldom reported. In this paper, the source, generation mechanism, infectivity, sampling and related outbreaks of NoV aerosol are summarized and discussed.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Humanos , Surtos de Doenças
10.
J Colloid Interface Sci ; 656: 485-494, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38007940

RESUMO

Interface engineering of heterostructures has emerged as a promising approach to enhance the catalytic activity of nonprecious electrocatalysts. Herein, a novel amorphous cobalt sulfide-crystalline nickel iron layered double hydroxide (a-CoS@NiFe-LDH) hybrid material is presented for application as an electrocatalyst for oxygen evolution reaction (OER). Benefitting from the well-matched energy level structures, the a-CoS@NiFe-LDH catalyst delivers a low overpotential of 221 ± 14 mV at an OER current density of 20 mA cm-2 and a small Tafel slope of 83.1 mV dec-1, showing good OER properties. First-principle computations reveal that the electronic interaction between amorphous cobalt sulfide (a-CoS) and crystalline nickel iron layered double hydroxide (NiFe-LDH) components within a-CoS@NiFe-LDH promotes the adsorbate evolution mechanism and reduces the adsorption energies for oxygen intermediates, thereby enhancing the activity and stability for OER. This work opens up a new avenue to enhance the OER catalytic efficiency via the construction of amorphous-crystalline heterostructures.

11.
Langmuir ; 39(51): 19027-19036, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38088916

RESUMO

Deciphering the facet-dependent surface properties of clay minerals holds vital significance in both fundamental research and practical engineering applications. To date, the anisotropic local charge density of serpentine surfaces still remains elusive, and thus, the interaction energies and associated aggregate structures between different crystal planes of serpentine cannot be quantitatively determined. In this work, different crystal planes of serpentine (i.e., SiO basal, MgOH basal, and edge) were selectively exposed, and their surface potentials and charge densities were determined using atomic force microscopy (AFM) force measurements coupled with Derjaguin-Landau-Verwey-Overbeek (DLVO) theory fitting. The SiO and edge planes consistently exhibited a permanently negative surface charge, whereas the point of zero charge (PZC) on the MgOH plane was estimated to be pH 9.0-11.0. Based on the interaction energy calculation between different serpentine planes, the aggregation structures of serpentine were predicted. Combined with scanning electron microscopy observation of freeze-dried samples, SiO-MgOH and MgOH-edge associations were found to dominate the aggregate structures at pH ≤ 9.0, thereby resulting in a stacking or "card-houses" structures. In contrast, all of the plane associations exhibited the repulsive interaction energy at pH 11.0, which led to a completely dispersed system, ultimately causing the most severe fine particle entrainment during froth flotation. Our work provides quantitative clarification of facet-dependent surface properties and aggregate structures of serpentine under different pH conditions, which will help improve the fundamental understanding of colloidal behaviors of clay minerals.

12.
Virol J ; 20(1): 263, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37964283

RESUMO

Human astroviruses (HAstV) are etiologic agents of acute gastroenteritis that most often afflict young children and elderly adults. Most studies of HAstV have focused on epidemiology. In this study, we collected 10 stool samples from a diarrhea outbreak from a diarrhea sentinel surveillance hospital in Beijing. Samples were evaluated immediately using parallel multiplex RT-qPCR and nanopore sequencing, and were then amplified by designed primers and Sanger sequencing to obtain whole genome sequences. Six isolates were categorized as HAstV-5 and subjected to whole genome analysis to characterize their genetic variation and evolution. Full genome analysis revealed low genetic variation (99.38-100% identity) among isolates. Phylogenetic analysis showed that all isolates were closely related to domestic strains Yu/1-CHN and 2013/Fuzhou/85. The recombination breakpoint of the six isolates was located at 2741 bp in the overlap region of ORF1a and ORF1b, similar to those of Yu/1-CHN and 2013/Fuzhou/85. Overall, our study highlights the combined use of RT-qPCR and sequencing as an important tool in rapid diagnosis and acquisition of whole genome sequences of HAstV.


Assuntos
Infecções por Astroviridae , Mamastrovirus , Nanoporos , Criança , Adulto , Humanos , Pré-Escolar , Idoso , Filogenia , Infecções por Astroviridae/diagnóstico , Infecções por Astroviridae/epidemiologia , Genótipo , Fezes , Diarreia/epidemiologia , Surtos de Doenças
13.
Curr Neuropharmacol ; 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37859307

RESUMO

BACKGROUND: It has been hypothesized that smoking is associated with the severity of negative symptoms. Until now, no studies have investigated whether the impact of smoking on negative symptoms is dependent on antioxidants. This study was designed to evaluate the effect of smoking on therapeutic response and total antioxidants capacity (TAOC) in antipsychotic-naïve first-episode (ANFE) patients. METHODS: The severity of the patient's symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS). A total of 237 ANFE patients were recruited and treated with risperidone (oral tablets, 4-6 mg/day twice a day) for 12 weeks. PANSS was assessed at baseline and a 12-week follow-up. Plasma TAOC levels were also assayed at baseline and week 12. RESULTS: Relative to nonsmokers with ANFE SZ, smokers had higher PANSS negative subscores. There was no significant difference in TAOC changes after 12 weeks of treatment with risperidone between smokers and non-smokers. However, we found greater improvement in negative symptoms in smokers compared to non-smokers. Further analysis in smokers with SZ demonstrated that improvements in negative symptoms were not associated with changes in TAOC. CONCLUSION: Our study suggested that smoking affected the severity of baseline negative symptoms and further contributed to their reduction after risperidone treatment. However, improvement in negative symptoms was not dependent on the changes in TAOC.

14.
Nat Commun ; 14(1): 6413, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828068

RESUMO

The assembly of cluster-based π-stacked porous supramolecular frameworks presents daunting challenges, including the design of suitable cluster building units, control of the sufficient C-H···π interactions, trade-off between structural dynamics and stability as well as understanding the resulting collective properties. Herein, we report a cluster-based C-H···π interaction-stacked porous supramolecular framework, namely, Cu12a-π, consisting of Cu12 nanocluster as a 6-connected node, which is further propagated to a dynamic porous supramolecular frameworks via dense intralayer C-H···π interactions, yielding permanent porosity. In addition, Cu12a-π can be transformed into cluster-based nonporous adaptive crystals (Cu12b-NACs) via ligand-exchange following a dissociation-reassembly mechanism. Moreover, Cu12a-π can efficiently remove 97.2% of iodine from saturated iodine aqueous solutions with a high uptake capacity of 2.96 g·g-1. These prospective results positioned at cluster-based porous supramolecular framework and enlighten follow-up researchers to design and synthesize such materials with better performance.

15.
J Med Virol ; 95(10): e29153, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37804388

RESUMO

The transmissibility is a crucial feature for norovirus, yet its quantitative estimation has been limited. Our objective was to estimate the basic reproduction number (R0 ) of norovirus and investigate its variation characteristics. Norovirus outbreaks reported from September 2016 to August 2021 in Beijing were analyzed. The susceptible-infected-removed compartment model was established to estimate R0 . Linear regression models and logistic regression models were used to explore the factors affecting the transmissibility of norovirus. The overall median R0 of norovirus was estimated as 2.1 (interquartile range [IQR] 1.8-2.5), with 650 norovirus outbreaks. The transmissibility of norovirus varied by year, outbreak setting and genotype. The R0 of norovirus during September 2019 to August 2020 (median 2.1, IQR 1.8-2.4) and September 2020 to August 2021 (median 2.0, IQR 1.7-2.3) was lower than that of September 2016 to August 2017 (median 2.3, IQR 1.8-2.7) (ß = 0.94, p = 0.05; ß = 0.93, p = 0.008). The R0 of norovirus for all other settings was lower than that for kindergarten (median 2.4, IQR 2.0-2.9) (primary school: median 2.0, IQR 1.7-2.4, ß = 0.94, p = 0.001; secondary school: median 1.7, IQR 1.5-2.0, ß = 0.87, p < 0.001; college: median 1.7, IQR 1.5-1.8, ß = 0.89, p = 0.03; other closed settings: median 1.8, IQR 1.5-2.0, ß = 0.90, p = 0.004). GⅡ.2[P16] outbreaks had a median R0 of 2.2 (IQR 1.8-2.7), which was higher than that for GⅡ.6[P7] outbreaks (median 1.8, IQR: 1.8-2.0, odds ratio = 0.19, p = 0.03; GⅡ.2[P16] as reference) and mixed-genotype outbreaks (median 1.7, IQR: 1.5-1.8, ß = 0.92, p = 0.02; mixed-genotype as reference). In kindergartens and primary schools, norovirus shows increased transmissibility, emphasizing the vulnerable population and high-risk settings. Furthermore, the transmissibility of norovirus may change over time and with virus evolution, necessitating additional research to uncover the underlying mechanisms.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Humanos , Pequim/epidemiologia , Norovirus/genética , Gastroenterite/epidemiologia , Infecções por Caliciviridae/epidemiologia , China/epidemiologia , Surtos de Doenças , Genótipo
16.
Micromachines (Basel) ; 14(9)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37763849

RESUMO

As an inertial sensor with excellent performance, the hemispherical resonator gyro is widely used in aerospace, weapon navigation and other fields due to its advantages of high precision, high reliability, and long life. Due to the uneven distributions of material properties and mass of the resonator in the circumferential direction, the frequencies of the two 4-antinodes vibration modes (operational mode) of resonator in different directions are different, which is called frequency splitting. Frequency splitting is the main error source affecting the accuracy of the hemispherical resonator gyro and must be suppressed. The frequency splitting is related to the structure of the resonator. For the planar-electrode-type hemispherical resonator gyro, in order to suppress the frequency splitting from the structure, improve the accuracy of the hemispherical resonator gyro, and determine and optimize the equivalent bottom angle parameters of the hemispherical resonator, this paper starts from the thin shell theory, and the 4-antinodes vibration mode and waveform precession model of the hemispherical resonator are researched. The effect of the equivalent bottom angle on the 4-antinodes vibration mode frequency value under different boundary conditions is theoretically analyzed and simulated. The simulation results show that the equivalent bottom angle affects the 4-antinodes vibration mode of the hemispherical resonator through radial constraints. The hemispherical resonator with mid-surface radius R=15 mm and shell thickness h=1 mm is the optimization object, and the stem diameter D and fillet radius R1 are experimental factors, with the 4-antinodes vibration mode frequency value and mass sensitivity factor as the response indexes. The central composite design is carried out to optimize the equivalent bottom angle parameters. The optimized structural parameters are: stem diameter D=7 mm, fillet radii R1=1 mm, R2=0.8 mm. The simulation results show that the 4-antinodes vibration mode frequency value is 5441.761 Hz, and the mass sensitivity factor is 3.91 Hz/mg, which meets the working and excitation requirements wonderfully. This research will provide guidance and reference for improving the accuracy of the hemispherical resonator gyro.

17.
J Am Chem Soc ; 145(36): 19523-19532, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37646485

RESUMO

Structural transformation of metal nanoclusters (NCs) is of great ongoing interest regarding their synthesis, stability, and reactivity. Although sporadic examples of cluster transformations have been reported, neither the underlying transformation mechanism nor the intermediates are unambiguous. Herein, we have synthesized a flexible 54-nuclei silver cluster (Ag54) by combining soft (tBuC≡C-) and hard (nPrCOO-) ligands. The existence of weakly coordinated nPrCOO- enhances the reactivity of Ag54, thus facilitating the dicarboxylic acid to induce structural transformation. X-ray structural analyses reveal that Ag54 transforms to Ag28 cluster-based 2D networks (Ag28a and Ag28b) induced by H2suc (succinic acid) and H2glu (glutaric acid), whereas with H2pda (2,2'-(1,2-phenylene)diacetic acid), a discrete Ag28 cluster (Ag28c) is isolated. The key intermediate Ag17 that emerges during the self-dissociation of Ag54 was isolated by using cryogenic recrystallization and characterized by X-ray crystallography. The "tandem transformation" mechanism for the structure evolution from Ag54 to Ag28a is established by time-dependent electrospray ionization mass spectrometry (ESI-MS) and UV-vis spectroscopy. In addition, the catalytic activity in the 4-nitrophenol reduction follows the sequence Ag28c > Ag28b > Ag28a > Ag54 due to more bare silver sites on the surface of the Ag28 cluster unit. Our findings not only open new avenues to the synthesis of silver NCs but also shed light on a better understanding of the structural transformation mechanism from one cluster to another or cluster-based metal-organic networks induced by dicarboxylates.

18.
Infect Genet Evol ; 114: 105491, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37597645

RESUMO

Norovirus (NoV) is the leading pathogen responsible for global acute gastroenteritis (AGE) outbreaks and sporadic cases. NoV evolves through gene mutation and recombination, leading to the emergence of new strains capable of causing global epidemics. This study aimed to learn the epidemiological characteristics of 39 GI.6[P11] NoV outbreaks in Beijing, China, from 2016 to 2019 and to analyze the genetic diversity and phylogenetic process of GI.6[P11] strains. The Bayesian phylogenetic analysis of partial VP1 and RNA-dependent RNA polymerase (RdRp) genes showed that GI.6[P11] strains were clustered into four subclades. Eleven whole genome sequences were obtained through the amplicon sequencing with 16 pairs of newly designed primers. The phylogenetic trees based on the whole genome and ORF1, 2, and 3 showed that the clustering of the 11 strains was consistent with that of partial VP1 and RdRp genes. The Bayesian inference revealed that the most recent ancestor (TMRCA) for the four subclades of the phylogenetic tree based on the whole genome sequences was 2012.42, 2014.81, 2011.74, and 2015.53, respectively. The recombination sites of GI.6[P11] strains in Beijing were located near the ORF1/2 junction. The histo-blood group antigens (HBGA) binding sites of GI.6[P11] strains in Beijing were conserved and there were some unique amino acid mutations in non-structural proteins in the ORF1 region.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Humanos , Pequim/epidemiologia , Norovirus/genética , Filogenia , Teorema de Bayes , Gastroenterite/epidemiologia , China/epidemiologia , Genótipo , Surtos de Doenças , RNA Polimerase Dependente de RNA/genética , Recombinação Genética , Infecções por Caliciviridae/epidemiologia
19.
J Int Med Res ; 51(8): 3000605231190899, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37561563

RESUMO

Laryngeal masks are widely used by anesthesiologists in clinical practice because of their advantages of no tracheal injury, minimal airway stimulation, limited airway tissue invasion, and easy implantation and airway establishment. We herein describe a patient with congenital heart disease who developed unilateral sublingual nerve paralysis after application of a laryngeal mask airway. The patient reported perioral numbness and exhibited unclear speech and slight right deviation of the tip of the tongue after surgery. On physical examination, the patient had normal muscle strength, symmetrical frontal lines, normal occlusion, and a normal nasolabial groove. We performed head computed tomography and computed tomography angiography to rule out cerebrovascular disease, and no abnormalities were found. The patient's imaging findings and clinical symptoms suggested unilateral right sublingual nerve palsy. After active treatment, the patient's symptoms improved by 75% on the third postoperative day and by 90% on the fifth postoperative day. Despite the extremely low incidence of sublingual nerve palsy after application of a laryngeal mask airway, anesthesiologists should be aware of this complication. Although the nerve palsy can resolve spontaneously, the nerve damage may be permanent.


Assuntos
Cardiopatias Congênitas , Máscaras Laríngeas , Humanos , Máscaras Laríngeas/efeitos adversos , Paralisia/etiologia , Língua , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/cirurgia , Pacientes
20.
J Biomed Mater Res B Appl Biomater ; 111(12): 2013-2024, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37477184

RESUMO

Different sterilization doses of the electron beam (E-beam) will change the properties of biomaterials and affect their clinical application. Acellular porcine cornea (APC) is a promising corneal substitute to alleviate the shortage of corneal resources. The residual DNA was significantly reduced to 18.50 ± 3.19 ng/mg, and the clearance rate of α-Gal was close to 100% after the treatment with freezing-thawing combined enzyme, indicating that the decellularization was effective. The effects of different E-beam doses at 0, 2, 8, 15, and 25 kGy on the APC were studied. With the increase in irradiation dose, the transmittance, tensile strength, and swelling ratio of APC gradually decreased, but the resistance to enzymatic degradation was stronger than that of non-irradiated APC, especially at 8 kGy. The structure of APC was denser after irradiation, but the dose of 25 kGy could cause partial collagen fiber fracture and increase the pore size. The cell viability of the APC irradiated by 15 and 25 kGy were greater than 80%. After the implantation in rabbit corneas, there was no obvious neovascularization and inflammation, but the dose of 25 kGy had a more destructive effect on the chemical bonds of collagen, which made the APC easier to be degraded. The thickness of APC in the 25 kGy group was thinner than that in the 15 kGy group 1 year after surgery, and the epithelium grew more slowly, so the E-beam dose of 15 kGy might be more suitable for the sterilization of APC.

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