Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
1.
Front Med (Lausanne) ; 11: 1413964, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39376649

RESUMO

Infection remains the leading cause of mortality in severe aplastic anemia (SAA) patients, with invasive fungal infections being the great threat. Aspergillus fumigatus accounts for most of the reported fungal infection cases. Here, we present a case of A. flavus infection in a patient with acute very severe aplastic anemia (VSAA) despite persistently negative clinical fungal tests. The patient was admitted to the hospital due to pancytopenia presisting for over a month and intermittent fever for 10 days. Elevated inflammatory indicators and abnormal lung imaging suggested infection, prompting consideration of fungal involvement. Despite negative results from multiple blood, sputum fungal cultures and the serum (1,3)-ß-D-glucan/galactomannan tests. Metagenomic next-generation sequencing (mNGS) on multiple blood samples, alongside clinical symptoms, confirmed A. flavus infection. Targeted antifungal treatment with liposomal amphotericin B and voriconazole significantly ameliorated pulmonary symptoms. Additionally, this study reviewed and compared the symptoms, diagnostic approaches, and treatments from prior Aspergillus infections in AA patients. It emphasizes critical role of early mNGS utilization in diagnosing and managing infectious diseases, offering insights for diagnosing and treating fungal infections in VSAA.

2.
World Neurosurg ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39278545

RESUMO

BACKGROUND: Deep brain stimulation (DBS) is a well-established treatment for Parkinson's disease (PD). However, infection following DBS surgery is a serious complication that can lead to the recurrence and worsening of Parkinson's symptoms or related hardware reimplantation, causing considerable patient suffering and financial burden. OBJECTIVE: This study aims to compare the therapeutic efficiency of different treatment approaches for scalp incision infections after DBS surgery in PD patients. METHODS: We conducted a retrospective review of patients with PD who experienced scalp infections following DBS at our hospital between January 2017 and December 2021. The patients were divided into 2 groups based on whether affected implants were removed or not. Fisher's exact test was applied to compare the reinfection rates between groups A and B. RESULTS: In group A, 4 patients underwent debridement only, and all of them experienced reinfection between 2 and 25 months after the initial treatment. In group B, 9 patients underwent debridement and removal of potentially affected implants. Among them, 8 patients underwent reimplantation of the DBS device within 3-6 months after the initial treatment, and no cases of reinfection occurred. However, 1 patient experienced reinfection in the postauricular incision and percutaneous tunnel 5 months after the initial treatment, resulting in the complete removal of the entire DBS system. The reinfection rate in group B (11.11%) was significantly lower than that in group A (100%, P = 0.007). CONCLUSIONS: Scalp incision infections following DBS surgery can affect deep tissues, and the implementation of a comprehensive treatment strategy involving local debridement and removal of potentially affected implants can significantly reduce the risk of infection recurrence and its spread.

3.
Nanomaterials (Basel) ; 14(16)2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39195397

RESUMO

As field effect transistors are reduced to nanometer dimensions, experimental and theoretical research has shown a gradual change in noise generation mechanisms. There are few studies on noise theory for small nanoscale transistors, and Monte Carlo (MC) simulations mainly focus on 2D devices with larger nanoscale dimensions. In this study, we employed MC simulation techniques to establish a 3D device simulation process. By setting device parameters and writing simulation programs, we simulated the raw data of channel current noise for a silicon-based metal-oxide-semiconductor field-effect transistor (MOSFET) with a 10 nm channel length and calculated the drain output current based on these data, thereby achieving static testing of the simulated device. Additionally, this study obtained a 3D potential distribution map of the device channel surface area. Based on the original data from the simulation analysis, this study further calculated the power spectral density of the channel current noise and analyzed how the channel current noise varies with gate voltage, source-drain voltage, temperature, and substrate doping density. The results indicate that under low-temperature conditions, the channel current noise of the 10 nm MOSFET is primarily composed of suppressed shot noise, with the proportion of thermal noise in the total noise slightly increasing as temperature rises. Under normal operating conditions, the channel current noise characteristics of the 10 nm MOSFET device are jointly characterized by suppressed shot noise, thermal noise, and cross-correlated noise. Among these noise components, shot noise is the main source of noise, and its suppression degree decreases as the bias voltage is reduced. These findings are consistent with experimental observations and theoretical analyses found in the existing literature.

4.
Small ; : e2403659, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39169702

RESUMO

The shrinkage of metal oxide semiconductor field effect transistor (MOSFET) to the small size of the nanoscale results in changes in their channel current noise composition. This paper determines the channel current noise composition of 90 nm MOSFET through experiments, and according to the device material and noise characteristics analysis, the channel current noise of 90 nm and below is obtained, which not only contains thermal noise and suppressed channel shot noise, but also adds suppressed gate tunneling shot noise and cross-correlation noise. Then, Monte Carlo simulation of 10 nm MOSFET noise is further used to determine the channel current composition of small size nanoscale devices. Subsequently, based on the device structure and fundamental characteristics of channel current noise, the channel current noise model is established. Finally, this model is employed to analyze the relationship between thermal noise, suppressed shot noise, cross-correlation noise, and channel current noise in relation to bias parameters and device characteristics. The theoretical results are basically consistent with the experimental and the simulated results, and the channel noise increases with the increase of bias voltage. This achievement holds promise for enhancing the operational efficiency, reliability, and lifetime of nanoscale small-sized MOSFET devices.

5.
J Biol Chem ; 300(8): 107528, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38960038

RESUMO

Therapeutic inhibition of the viral protein Nef is an intriguing direction of antiretroviral drug discovery-it may revitalize immune mechanisms to target, and potentially clear, HIV-1-infected cells. Of the many cellular functions of Nef, the most conserved is the downregulation of surface CD4, which takes place through Nef hijacking the clathrin adaptor protein complex 2 (AP2)-dependent endocytosis. Our recent crystal structure has unraveled the molecular details of the CD4-Nef-AP2 interaction. Guided by the new structural knowledge, we have developed a fluorescence polarization-based assay for inhibitor screening against Nef's activity on CD4. In our assay, AP2 is included along with Nef to facilitate the proper formation of the CD4-binding pocket and a fluorescently labeled CD4 cytoplasmic tail binds competently to the Nef-AP2 complex generating the desired polarization signal. The optimized assay has a good signal-to-noise ratio, excellent tolerance of dimethylsulfoxide and detergent, and the ability to detect competitive binding at the targeted Nef pocket, making it suitable for high-throughput screening.


Assuntos
Antígenos CD4 , Regulação para Baixo , Polarização de Fluorescência , HIV-1 , Ensaios de Triagem em Larga Escala , Produtos do Gene nef do Vírus da Imunodeficiência Humana , Produtos do Gene nef do Vírus da Imunodeficiência Humana/metabolismo , Produtos do Gene nef do Vírus da Imunodeficiência Humana/antagonistas & inibidores , Produtos do Gene nef do Vírus da Imunodeficiência Humana/química , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética , Antígenos CD4/metabolismo , Antígenos CD4/química , Humanos , Polarização de Fluorescência/métodos , HIV-1/metabolismo , HIV-1/efeitos dos fármacos , Ensaios de Triagem em Larga Escala/métodos , Regulação para Baixo/efeitos dos fármacos , Complexo 2 de Proteínas Adaptadoras/metabolismo , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/química , Ligação Proteica
6.
J Biol Chem ; 300(8): 107529, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38960039

RESUMO

The multifunctional, HIV-1 accessory protein Nef enables infected cells to evade host immunity and thus plays a key role in viral pathogenesis. One prominent function of Nef is the downregulation of major histocompatibility complex class I (MHC-I), which disrupts antigen presentation and thereby allows the infected cells to evade immune surveillance by the cytotoxic T cells. Therapeutic inhibition of this Nef function is a promising direction of antiretroviral drug discovery as it may revitalize cytotoxic T cells to identify, and potentially clear, hidden HIV-1 infections. Guided by the crystal structure of the protein complex formed between Nef, MHC-I, and the hijacked clathrin adaptor protein complex 1, we have developed a fluorescence polarization-based assay for inhibitor screening against Nef's activity on MHC-I. The optimized assay has a good signal-to-noise ratio, substantial tolerance of dimethylsulfoxide, and excellent ability to detect competitive inhibition, indicating that it is suitable for high-throughput screening.


Assuntos
Regulação para Baixo , Polarização de Fluorescência , HIV-1 , Ensaios de Triagem em Larga Escala , Antígenos de Histocompatibilidade Classe I , Produtos do Gene nef do Vírus da Imunodeficiência Humana , Produtos do Gene nef do Vírus da Imunodeficiência Humana/metabolismo , Produtos do Gene nef do Vírus da Imunodeficiência Humana/antagonistas & inibidores , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética , Produtos do Gene nef do Vírus da Imunodeficiência Humana/química , HIV-1/efeitos dos fármacos , HIV-1/metabolismo , Humanos , Polarização de Fluorescência/métodos , Ensaios de Triagem em Larga Escala/métodos , Regulação para Baixo/efeitos dos fármacos , Antígenos de Histocompatibilidade Classe I/metabolismo , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/química
7.
J Perianesth Nurs ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980240

RESUMO

PURPOSE: There are currently no pediatric studies examining the effects of deep breathing on perioperative pain and anxiety. This study sought to determine the effect of short-term deep breathing exercises on perioperative anxiety and pain in pediatric patients and their parents. DESIGN: A randomized controlled trial was conducted in the Department of Orthopaedic Surgery where pediatric patients about to undergo surgery were allocated to a control group or a deep breathing group. In the intervention group, patients and their main guardian were guided to practice 10 minutes of deep breathing exercises twice a day for 3 to 4 days prior to surgery. Perioperative anxiety and pain were measured for both the children and parents as outcome indicators. METHODS: Perioperative anxiety was measured using the modified Yale Preoperative Anxiety Scale-Short Form (mYPAS-SF) and state anxiety was measured using the State-Trait Anxiety Inventory (STAI). Patients reported their pain levels daily using the Wong-Baker FACES Pain Rating Scale. The following cutoffs were determined as high levels of anxiety: STAI (adult) > 44, STAI (child) > 36, and mYPAS-SF ≥ 30. FINDINGS: No significant differences were found in the STAI, mYPAS-SF, and Wong-Baker FACES Pain Rating Scale scores of the patients between the intervention and control group. Overall statistics showed that parents had significantly higher postoperative state anxiety levels toward female children (44.93 ± 9.01) compared to male children (40.18 ± 9.89). Preoperative and postoperative parental state anxiety levels were correlated with the child's postoperative anxiety. Furthermore, children's postoperative state anxiety was slightly correlated with postoperative pain. CONCLUSIONS: Short-term use of our deep breathing exercises was ineffective in reducing incidences of perioperative pain and anxiety in pediatric orthopedic patients. A longer period of deep breathing administration may be required for the intervention to be effective. Parental anxiety may have an effect on anxiety levels in children, and postoperative parental anxiety may be affected by the gender of the child.

8.
Chem Commun (Camb) ; 60(35): 4667-4670, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38591607

RESUMO

Rh-catalyzed hydroaminomethylation has been developed with acid sulfoxantphos and ZSM-5. Linear amines were obtained in good yields (71-95%) with high l/b ratios (up to 132.4) and excellent TON values (up to 23 760). The ZSM-5 and SO3H group of ligands improved the performances of hydroformylation and reductive amination.

10.
Small ; 20(8): e2303834, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37867216

RESUMO

A porous noncovalent organic framework with AIE effect is designed and synthesized as the support for gold nanoparticles (AuNPs). The framework is fabricated through the electrostatic complexation between carboxymethyl cellulose and tetraphenylethene-containing ammonium surfactant, which can complex AuNPs via the noncovalent interactions to offer a heterogeneous catalyst. Compared to the covalent modification on cellulose, this noncovalent framework gains superiorities in the catalyst synthesis and the size control of AuNPs. The AIE property and water-insolubility allow such heterogeneous catalysts to be easily detected, separated, and recycled, opening a new pathway for the reduction of nitrobenzene compounds and some dye compounds in aqueous conditions, which present the features of green chemistry. The use of cellulose for developing new heterogeneous metal catalysts, especially in a noncovalent way, would promote the value-added utilization of cellulose. This work provides a design strategy for gaining heterogeneous metal catalysts by taking advantage of natural bioresources.

11.
Brain Sci ; 13(7)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37508965

RESUMO

Compound words in psycholinguistics pose a significant challenge for researchers as their meaning involves more than the sum of their parts. The role of semantic relations in this process is crucial, and studies have reported a phenomenon known as relation priming. It suggests that previously encountered relations enhance the processing of subsequent words with the same relation. Notably, this priming effect is limited to cases where there is morpheme repetition between the priming and target words. In the present study, 33 samples from the target group were selected, and the within-subject design of 3 morphemes (modifier-shared, head-shared, non-repeated) × 2 relations (relation-same, relation-different) was adopted to explore whether the relation priming effect would occur without morpheme repetition and its time course. Significant relation priming effects were found in both behavioral and electrophysiological experimental results. These findings indicating relation priming can occur independently of morpheme repetition, and it has been activated at a very early stage (about 200 ms). As the word processing progresses, this activation gradually strengthens, indicating that the relation role is slowly increasing in the process of compound word recognition. It may first be used as context information to help determine the constituent morphemes' meaning. After the meaning access of the constituent morphemes, they begin to play a role in the semantic composition process. This study uses electrophysiological technology to precisely describe the representation of relation and its time course for the first time, which gives us a deeper understanding of the relation priming process, and at the same time, sheds light on the meaning construction process of compounds.

12.
J Chromatogr A ; 1700: 464046, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37167804

RESUMO

To solve the problems of unstable adsorption performance and high organic solvent consumption of traditional molecular imprinting materials, we developed a water-resistant and highly adsorptive molecularly imprinted sulfamethazine polymer (MIP) through a novel synthetic strategy consisting of the application of mixed functional monomers combined with hydrophobic crosslinkers. The results showed that the imprinting factor of the prepared MIP was increased from 0.93 to 4.38, and that the relative selection coefficient k' was 5.59. With the application of the material to be developed as a solid-phase extraction (SPE) filler for sulfonamides (SAs) in milk combined with UPLC-MS/MS, the validated method showed a sensitive quantification limit (0.89 µg/kg), a steady recovery (95.55%-97.97%) and an excellent precision (0.08%-2.92% RSD). Moreover, after 5 times usage, the recovery rate of MIP-SPE was still above 90%. Therefore, the prepared materials showed high performance of molecular adsorption and were water-resistant, which was also considered an excellent filler of SPE for SAs extraction in food or other fields.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Animais , Polímeros/química , Espectrometria de Massas em Tandem , Leite/química , Cromatografia Líquida , Água/química , Sulfonamidas/análise , Extração em Fase Sólida/métodos , Impressão Molecular/métodos , Adsorção , Cromatografia Líquida de Alta Pressão/métodos
13.
Chem Commun (Camb) ; 59(35): 5237-5240, 2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37040199

RESUMO

The Rh/BINAPa and ZSM-35(10) co-catalyzed tandem hydroformylation-acetalization of olefins has been developed. A series of olefins with various alcohols performed well in the process, affording the corresponding acetals with high regioselectivities (l/b ≥ 30.5) and excellent catalytic activities (TON of the Rh catalyst up to 4.3 × 104). Control experiments and DFT calculations indicated that the Rh/L11-catalyzed hydroformylation occurred in the solvent outside the molecular sieve, while the acetalization of intermediate aldehydes with alcohols takes place mainly in the interior of the molecular sieve.

14.
Front Psychol ; 13: 1047936, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36571010

RESUMO

Recent years have seen a heated discussion on what influences employees' recognition of enterprise brand equity among the psychological community. Some empirical evidence suggests that the brand equity of consumers and brand equity of sales are two categories that should be studied. However, more recent discussions have focused more on the former. In contrast, this study discusses the factors influencing brand equity based on the employee level. Moreover, this paper examines whether FinTech can help companies get out of financing difficulties and thus improve employees' brand equity recognition. This research illustrates how FinTech has become an essential driver of brand equity value. Based on micro panel data on enterprises from 2011 to 2019, we analyze the transmission mechanism between the two factors and the mediating role of financing constraints. FinTech's development promotes employees' recognition of corporate brand equity, and financing constraints are an essential transmission path between the two factors. Furthermore, the impact of financing constraints on employee brand equity identity is characterized by cross-regional economic heterogeneity. In contrast, the development of FinTech characterizes the cross-enterprise heterogeneity in employees' recognition of brand equity value. Altogether, this study demonstrates the promising application of FinTech in influencing the mechanisms of employee brand equity.

15.
Chem Commun (Camb) ; 58(71): 9906-9909, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35975808

RESUMO

Benefiting from a high overpotential of the competitive hydrogen evolution reaction with a carbon paper cathode, the desired electrochemical reduction of imines was achieved with high faradaic efficiency by using H2O as a H-source. With this sustainable atom-economic strategy, a series of potentially versatile amines were obtained in medium-to-high yields (49-86%).

16.
Front Neurosci ; 16: 929273, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35979336

RESUMO

Multiple system atrophy with predominant parkinsonism (MSA-P) is a highly incapacitating disease with a short life expectancy and symptomatic therapy is still limited. In this report, we presented the case of a 65-year-old woman with a 3-year history of severe rigidity, bradykinesia, and gait dysfunction alongside severe freezing of gait diagnosed with MSA-P. She underwent combined therapy of bilateral subthalamic nucleus deep brain stimulation (DBS) and low-thoracic spinal cord stimulation (SCS). The double-blind evaluation of the Movement Disorder Society Sponsored Revision of the Unified Parkinson's Disease Rating Scale part III and 7-m Timed Up and Go at follow-ups showed her cardinal parkinsonian symptoms benefit significantly from DBS stimulation, while the improvement of SCS was mainly embodied in lower-limb symptoms. The combined stimulation achieved a better improvement of motor function than either DBS or SCS stimulation alone. Most notably, the improvement of lower-limb symptoms was significantly enhanced by the combined stimulation.

17.
Front Plant Sci ; 13: 897528, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783961

RESUMO

For a long history, herbal medicines have made significant contributions to human health all around the world. However, the exploration of an effective approach to illustrate their inner quality remains a challenge. So, it is imperative to develop new methods and technologies to characterize and identify quality markers of herbal medicines. Taking Isatidis Radix, the dried root of Isatis indigotica as an example, desorption electrospray ionization (DESI), in combination with quadrupole-time-of-flight mass spectrometry (Q-TOF/MS), was applied in this work for the first time to reveal the comprehensive spatial distribution of metabolites and, further, to illustrate quality characters of this herbal medicine. After simple pretreatment, 102 metabolites including alkaloids, sulfur-containing compounds, phenylpropanoids, nucleosides, amino acids, organic acids, flavonoids, phenols, terpenes, saccharides, peptides, and sphingolipids were characterized, some of which were successfully localized and visualized in the transverse section of the root. Based on the ion images, samples with different quality characters were distinguished unambiguously by the pattern recognition method of orthogonal partial least squares discrimination analysis (OPLS-DA). Simultaneously, 11 major influencing components exerting higher ion intensities in superior samples were identified as the potential quality markers of Isatidis Radix. Desorption electrospray ionization (DESI) mass spectrometry imaging (MSI), together with chemometric analysis could not only improve the understanding of the plant biology of herbal medicines but also be beneficial in the identification of quality markers, so as to carry out better quality control of herbal medicines.

18.
Org Lett ; 24(19): 3471-3476, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35546086

RESUMO

Molecular electrophotocatalysis has emerged as a powerful strategy for the development of sustainable synthetic protocols. With the proof-of-concept, we exploited a versatile electrophotocatalytic deaminative alkylation approach. Mechanistic investigation indicated that in situ recycling of the alkyl radicals was the key point. Notably, ligand modification and late-stage functionalization of pharmaceuticals were also established, highlighting its feasibility in practical utilization.


Assuntos
Desaminação , Alquilação
19.
Chin Med ; 17(1): 35, 2022 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-35248086

RESUMO

Mass spectrometry imaging is a frontier technique which connects classical mass spectrometry with ion imaging. Various types of chemicals could be visualized in their native tissues using mass spectrometry imaging. Up to now, the most commonly applied mass spectrometry imaging techniques are matrix assisted laser desorption ionization mass spectrometry imaging, desorption electrospray ionization mass spectrometry imaging and secondary ion mass spectrometry imaging. This review gives an introduction to the principles, development and applications of commonly applied mass spectrometry imaging techniques, and then illustrates the application of mass spectrometry imaging in the investigation of traditional Chinese medicine. Recently, mass spectrometry imaging has been adopted to explore the spatial distribution of endogenous metabolites in traditional Chinese medicine. Data collected from mass spectrometry imaging can be further utilized to search for marker components of traditional Chinese medicine, discover new compounds from traditional herbs, and differentiate between medicinal plants that are similar in botanical features. Moreover, mass spectrometry imaging also plays a role in revealing the pharmacological and toxicological mechanisms of traditional Chinese medicine.

20.
Nanomedicine ; 41: 102522, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35032631

RESUMO

We developed surface-enhanced Raman scattering-lateral flow immunoassay (SERS-LFIA) biosensor strips based on SiO2@Au nanoparticles (NPs) for the specific and highly sensitive detection of ricin, staphylococcal enterotoxin B (SEB), and botulinum neurotoxin type A (BoNT/A). SiO2@Au NPs were used to prepare SERS tags with useful properties, such as light weight, uniform particle size, good dispersion, and high SERS performance. The detection limit of the SERS-LFIA strips developed herein for ricin, SEB, and BoNT/A was 0.1, 0.05, and 0.1 ng/mL. Their sensitivity was 100-fold higher than that of colloidal gold-LFIA strips, and the same batch of strips had good repeatability. Moreover, the test was completed within 15 min, indicating that the strips are suitable for the rapid and on-site detection of the said toxins. The SERS-LFIA strips based on SiO2@Au NPs developed herein for the detection of toxins are important to the prevention of bioterrorism attacks.


Assuntos
Nanopartículas Metálicas , Dióxido de Silício , Ouro , Imunoensaio , Limite de Detecção , Análise Espectral Raman
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA