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1.
J Biol Chem ; 300(8): 107529, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38960039

ABSTRACT

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.

2.
J Biol Chem ; 300(8): 107528, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38960038

ABSTRACT

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.

3.
J Perianesth Nurs ; 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38980240

ABSTRACT

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.

4.
Chem Commun (Camb) ; 60(35): 4667-4670, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38591607

ABSTRACT

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.

6.
Small ; 20(8): e2303834, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37867216

ABSTRACT

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.

7.
Brain Sci ; 13(7)2023 Jul 06.
Article in English | MEDLINE | ID: mdl-37508965

ABSTRACT

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.

8.
J Chromatogr A ; 1700: 464046, 2023 Jul 05.
Article in English | MEDLINE | ID: mdl-37167804

ABSTRACT

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.


Subject(s)
Molecular Imprinting , Molecularly Imprinted Polymers , Animals , Polymers/chemistry , Tandem Mass Spectrometry , Milk/chemistry , Chromatography, Liquid , Water/chemistry , Sulfonamides/analysis , Solid Phase Extraction/methods , Molecular Imprinting/methods , Adsorption , Chromatography, High Pressure Liquid/methods
9.
Chem Commun (Camb) ; 59(35): 5237-5240, 2023 Apr 27.
Article in English | MEDLINE | ID: mdl-37040199

ABSTRACT

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.

10.
Front Psychol ; 13: 1047936, 2022.
Article in English | MEDLINE | ID: mdl-36571010

ABSTRACT

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.

11.
Chem Commun (Camb) ; 58(71): 9906-9909, 2022 Sep 01.
Article in English | MEDLINE | ID: mdl-35975808

ABSTRACT

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%).

12.
Front Neurosci ; 16: 929273, 2022.
Article in English | MEDLINE | ID: mdl-35979336

ABSTRACT

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.

13.
Front Plant Sci ; 13: 897528, 2022.
Article in English | MEDLINE | ID: mdl-35783961

ABSTRACT

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.

14.
Org Lett ; 24(19): 3471-3476, 2022 05 20.
Article in English | MEDLINE | ID: mdl-35546086

ABSTRACT

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.


Subject(s)
Deamination , Alkylation
15.
Chin Med ; 17(1): 35, 2022 Mar 05.
Article in English | MEDLINE | ID: mdl-35248086

ABSTRACT

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.

16.
Nanomedicine ; 41: 102522, 2022 04.
Article in English | MEDLINE | ID: mdl-35032631

ABSTRACT

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.


Subject(s)
Metal Nanoparticles , Silicon Dioxide , Gold , Immunoassay , Limit of Detection , Spectrum Analysis, Raman
17.
Am J Phys Med Rehabil ; 101(5): 446-453, 2022 05 01.
Article in English | MEDLINE | ID: mdl-34261896

ABSTRACT

OBJECTIVE: The purpose of this study was to investigate the therapeutic effects of transcranial direct current stimulation on swallowing function in poststroke patients. DESIGN: We searched for potentially eligible randomized controlled trials from electronic databases, including the PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Wanfang, and Chinese Science and Technology Periodical (VIP) databases, from their inception to January 15, 2021. All statistical analyses were performed using RevMan 5.4, and the standardized mean difference with 95% confidence intervals was estimated for the swallowing function outcomes and to understand the mean effect size. RESULTS: Ten studies involving 343 participants were included in this meta-analysis. The overall analyses demonstrated a significant effect size for swallowing function. Subgroup analyses suggested that both acute and chronic stroke patients showed significant effects on swallowing function after transcranial direct current stimulation. Furthermore, compared with sham stimulation, transcranial direct current stimulation anodal to the affected, unaffected, and bilateral hemispheres can produce a significant effect size for swallowing function in stroke patients. CONCLUSIONS: This meta-analysis showed that transcranial direct current stimulation is likely to be effective for the recovery of dysphagia in poststroke patients, in the acute or chronic phase, and that the effect of anodal transcranial direct current stimulation to unaffected hemispheres is larger.


Subject(s)
Deglutition Disorders , Stroke Rehabilitation , Stroke , Transcranial Direct Current Stimulation , Deglutition , Deglutition Disorders/etiology , Deglutition Disorders/therapy , Humans
18.
Talanta ; 237: 122919, 2022 Jan 15.
Article in English | MEDLINE | ID: mdl-34736655

ABSTRACT

Diazepam (DZP) was routinely prescribed to a large population troubled with anxiety disorders. However, due to the overuse and misuse, DZP and its chlorination disinfection byproduct 2-methylamino-5-chlorobenzophenone (MACB) caused environmental pollution and can be detected ubiquitously in drinking water in Beijing, China. However, little information is known about the metabolic dynamics of MACB. Here, we established desorption electrospray ionization mass spectrometry (DESI-MS) imaging method to visually and quantitatively assess the distribution and metabolism of MACB in zebrafish. The results showed that MACB specifically accumulated in spinal cord particularly in female zebrafish. Meanwhile, the accumulation of MACB could pass through the blood-brain barrier (BBB) and induced microglial phagocytosis of neurons. Therefore, the intervention strategies should be explored to restrict the release of such substances, eliminating the potential risks for both human beings and the eco-environment.


Subject(s)
Spectrometry, Mass, Electrospray Ionization , Zebrafish , Animals , Diazepam , Disinfection , Female , Halogenation , Humans
19.
Front Hum Neurosci ; 15: 707816, 2021.
Article in English | MEDLINE | ID: mdl-34512294

ABSTRACT

BACKGROUND: Hardware-related infection in deep brain stimulation (DBS) is one of the most commonly reported complications frequently resulting in the removal of implantable pulse generator (IPG). OBJECTIVE: The aim of this study was to establish a useful strategy to better prevent and treat those infections and to improve the preservation rates of IPG. METHODS: We conducted a retrospective and historical controlled study of all adult patients (≥18 years old) who had undergone initial DBS implantation at a single center. All participants were enrolled in the control group (between June 2005 and June 2014) or intervention group (between July 2014 and May 2019) based on their surgery dates. We used the intraoperative irrigation with hydrogen dioxide solution in the intervention group. Based on the dates of diagnosis, patients with hardware-related infection after DBS were enrolled in group A (between June 2005 and June 2014) or group B (between July 2014 and May 2019). IPG-sparing algorithm (Isa) was applied for group B. The early-onset IPG infections of the control and intervention groups were evaluated. The IPG preservation rates in both groups A and B were statistically analyzed. RESULTS: Six cases of early IPG infection and subsequent IPG removal occurred in the control group, while none occurred after intraoperative usage of the hydrogen dioxide in the intervention group. IPG preservation rate of infected cases in group B was significantly higher than that in group A (70% vs.16%, p = 0.004). CONCLUSION: The combined application of hydrogen dioxide solution and Isa seems to be an effective strategy to prevent IPG infection.

20.
Mikrochim Acta ; 188(6): 206, 2021 05 27.
Article in English | MEDLINE | ID: mdl-34046739

ABSTRACT

A portable surface-enhanced Raman scattering (SERS)-lateral flow immunoassay (LFIA) detector has been developed for the automatic and highly sensitive detection of West Nile virus (WNV) non-structural protein 1 (NS1) and actual WNV samples. Au@Ag nanoparticles (Au@Ag NPs) labeled with double-layer Raman molecules were used as SERS tags to prepare WNV-specific SERS-LFIA strips. On this platform, the WNV-specific antigen NS1 protein was quantitatively and sensitively detected. The detection limit for the WNV NS1 protein was 0.1 ng/mL, which was 100-fold more sensitive than visual signals. The detection limit for inactivated WNV virions was 0.2 × 102 copies/µL. The sensitivity of the SERS-LFIA detector was comparable to that of the fluorescence quantitative reverse transcription-polymerase chain reaction assay. The prepared SERS-LFIA strips exhibited high sensitivity and good specificity for WNV. Thus, the strips developed herein have clinical application value. Moreover, the portable SERS-LFIA detector enabled automatic and rapid detection of the SERS-LFIA strips. The platform established herein is expected to make a substantial contribution to the diagnosis and control of outbreaks of emerging infectious diseases, including WNV.


Subject(s)
Immunoassay/methods , Spectrum Analysis, Raman/methods , Viral Nonstructural Proteins/analysis , West Nile virus/chemistry , Antibodies, Immobilized/immunology , Gold/chemistry , Limit of Detection , Metal Nanoparticles/chemistry , Silver/chemistry , Viral Nonstructural Proteins/immunology , West Nile Fever/diagnosis
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