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1.
Dig Dis Sci ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965159

ABSTRACT

BACKGROUND: Chronic hepatitis C (CHC) increases the risk of liver cirrhosis (LC) and hepatocellular carcinoma (HCC). This nationwide cohort study assessed the effectiveness of viral eradication of CHC. METHODS: The Taiwanese chronic hepatitis C cohort and Taiwan hepatitis C virus (HCV) registry are nationwide HCV registry cohorts incorporating data from 23 and 53 hospitals in Taiwan, respectively. This study included 27,577 individuals from these cohorts that were given a diagnosis of CHC and with data linked to the Taiwan National Health Insurance Research Database. Patients received either pegylated interferon and ribavirin or direct-acting antiviral agent therapy for > 4 weeks for new-onset LC and liver-related events. RESULTS: Among the 27,577 analyzed patients, 25,461 (92.3%) achieved sustained virologic response (SVR). The mean follow-up duration was 51.2 ± 48.4 months, totaling 118,567 person-years. In the multivariable Cox proportional hazard analysis, the hazard ratio (HR) for incident HCC was 1.39 (95% confidence interval [CI]: 1.00-1.95, p = 0.052) among noncirrhotic patients without SVR compared with those with SVR and 1.82 (95% CI 1.34-2.48) among cirrhotic patients without SVR. The HR for liver-related events, including HCC and decompensated LC, was 1.70 (95% CI 1.30-2.24) among cirrhotic patients without SVR. Patients with SVR had a lower 10-year cumulative incidence of new-onset HCC than those without SVR did (21.7 vs. 38.7% in patients with LC, p < 0.001; 6.0 vs. 18.4% in patients without LC, p < 0.001). CONCLUSION: HCV eradication reduced the incidence of HCC in patients with and without LC and reduced the incidence of liver-related events in patients with LC.

2.
Magnes Res ; 36(4): 54-68, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38953415

ABSTRACT

To evaluate the analgesic effects of intravenous magnesium in patients undergoing thoracic surgery. Randomised clinical trials (RCTs) were systematically identified from MEDLINE, EMBASE, Google Scholar and the Cochrane Library from inception to May 1st, 2023. The primary outcome was the effect of intravenous magnesium on the severity of postoperative pain at 24 hours following surgery, while the secondary outcomes included association between intravenous magnesium and pain severity at other time points, morphine consumption, and haemodynamic changes. Meta-analysis of seven RCTs published between 2007 and 2019, involving 549 adults, showed no correlation between magnesium and pain scores at 1-4 (standardized mean difference [SMD]=-0.06; p=0.58), 8-12 (SMD=-0.09; p=0.58), 24 (SMD=-0.16; p=0.42), and 48 (SMD=-0.27; p=0.09) hours post-surgery. Perioperative magnesium resulted in lower equivalent morphine consumption at 24 hours post-surgery (mean difference [MD]=-25.22 mg; p=0.04) and no effect at 48 hours (MD=-4.46 mg; p=0.19). Magnesium decreased heart rate (MD = -5.31 beats/min; p=0.0002) after tracheal intubation or after surgery, but had no effect on postoperative blood pressure (MD=-6.25 mmHg; p=0.11). There was a significantly higher concentration of magnesium in the magnesium group compared with that in the placebo group (MD = 0.91 mg/dL; p<0.00001). This meta-analysis provides evidence supporting perioperative magnesium as an analgesic adjuvant at 24 hours following thoracic surgery, but no opioid-sparing effect at 48 hours post-surgery. The severity of postoperative pain did not significantly differ between any of the postoperative time points, irrespective of magnesium. Further research on perioperative magnesium in various surgical settings is needed.


Subject(s)
Magnesium , Pain, Postoperative , Randomized Controlled Trials as Topic , Humans , Pain, Postoperative/prevention & control , Pain, Postoperative/drug therapy , Magnesium/administration & dosage , Magnesium/therapeutic use , Thoracic Surgical Procedures/adverse effects , Analgesia/methods
3.
Transl Pediatr ; 13(6): 877-888, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38984032

ABSTRACT

Background: The clinical features and prognosis of intussusception in children vaccinated against rotavirus were undefined. Hence, we conducted the study to explore the clinical characteristics and outcomes of primary intussusception patients who received rotavirus vaccine. Methods: A single-center retrospective study was performed in 327 primary intussusception patients between January 2019 and December 2021. Of these, 168 were vaccinated against rotavirus and 159 were not, the latter serving as the control group. Data on patients' clinical characteristics, commonly used inflammatory biomarkers, treatment, and outcomes were collected and evaluated. Results: Most of the vaccination group received pentavalent rotavirus vaccine produced by Merck, USA (89.88%). There were no differences in demographic characteristics, time from onset to hospital attendance, clinical symptoms and signs between the vaccination group and the control group. The success rate of air enema reduction in the vaccination group was higher than that in the control group (98.21% vs. 88.68%, q=0.01). The vaccination group had lower rates of surgery and complication (1.79% vs. 11.32%, q=0.008; 2.98% vs. 12.58%, q=0.006). Both platelet-lymphocyte ratio (PLR) and C-reactive protein (CRP) levels were lower in the vaccinated group (q=0.02, q=0.004). Higher CRP level [odds ratio (OR): 1.635; 95% confidence interval (CI): 1.248-2.143; P=0.006] and the longer time from onset to hospital attendance (OR: 3.040; 95% CI: 2.418-12.133; P=0.01) were associated with increased adverse events. Rotavirus vaccination (OR: 0.527; 95% CI: 0.103-0.751; P=0.02) was associated with a reduction in the probability of adverse events. Conclusions: Adverse events such as surgery and complications were lower in the vaccination group. Rotavirus vaccination was an independent protective factor for adverse events in patients with primary intussusception.

4.
Heliyon ; 10(12): e32494, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38948030

ABSTRACT

Objective: To explore the potential targets for melatonin in the treatment of periodontitis through network pharmacologic analysis and experimental validation via in vivo animal models and in vitro cellular experiments. Materials and methods: In this study, we first screened melatonin targets from Pharm Mapper for putative targets, Drug Bank, and TCMSP databases for known targets. Then, disease database was searched and screened for differential expressed genes associated with periodontitis. The intersection of disease and melatonin-related genes yielded potential target genes of melatonin treatment for periodontitis. These target genes were further investigated by protein-protein interaction network and GO/KEGG enrichment analysis. In addition, the interactions between melatonin and key target genes were interrogated by molecular docking simulations. Then, we performed animal studies to validate the therapeutic effect of melatonin by injecting melatonin into the peritoneal cavity of ligation-induced periodontitis (LIP) mice. The effects of melatonin on the predicted target proteins were also analyzed using Western blot and immunofluorescence techniques. Finally, we constructed an in vitro cellular model and validated the direct effect of melatonin on the predicted targets by using qPCR. Results: We identified 8 potential target genes by network pharmacology analysis. Enrichment analysis suggests that melatonin may treat periodontitis by inhibiting the expression of three potential targets (MPO, MMP8, and MMP9). Molecular docking results showed that melatonin could effectively bind to MMP8 and MMP9. Subsequently, melatonin was further validated in a mouse LIP model to inhibit the expression of MPO, MMP8, and MMP9 in the periodontal tissue. Finally, we verified the direct effect of melatonin on the mRNA expression of MPO, MMP8, and MMP9 in an in vitro cellular model. Conclusions: Through a combination of network pharmacology and experimental validation, this study provides a more comprehensive understanding of the mechanism of melatonin to treat periodontitis. Our study suggests that MPO, MMP8, and MMP9 as key target genes of melatonin to treat periodontitis. These findings present a more comprehensive basis for further investigation into the mechanisms of pharmacological treatment of periodontitis by melatonin.

5.
Cell Mol Life Sci ; 81(1): 294, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38977495

ABSTRACT

The obligate intracellular parasite Toxoplasma gondii causes life-threatening toxoplasmosis to immunocompromised individuals. The pathogenesis of Toxoplasma relies on its swift dissemination to the central nervous system through a 'Trojan Horse' mechanism using infected leukocytes as carriers. Previous work found TgWIP, a protein secreted from Toxoplasma, played a role in altering the actin cytoskeleton and promoting cell migration in infected dendritic cells (DCs). However, the mechanism behind these changes was unknown. Here, we report that TgWIP harbors two SH2-binding motifs that interact with tyrosine phosphatases Shp1 and Shp2, leading to phosphatase activation. DCs infected with Toxoplasma exhibited hypermigration, accompanying enhanced F-actin stress fibers and increased membrane protrusions such as filopodia and pseudopodia. By contrast, these phenotypes were abrogated in DCs infected with Toxoplasma expressing a mutant TgWIP lacking the SH2-binding motifs. We further demonstrated that the Rho-associated kinase (Rock) is involved in the induction of these phenotypes, in a TgWIP-Shp1/2 dependent manner. Collectively, the data uncover a molecular mechanism by which TgWIP modulates the migration dynamics of infected DCs in vitro.


Subject(s)
Cell Movement , Dendritic Cells , Protein Tyrosine Phosphatase, Non-Receptor Type 11 , Protein Tyrosine Phosphatase, Non-Receptor Type 6 , Protozoan Proteins , Toxoplasma , Toxoplasma/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 11/metabolism , Protein Tyrosine Phosphatase, Non-Receptor Type 11/genetics , Dendritic Cells/metabolism , Dendritic Cells/parasitology , Animals , Protein Tyrosine Phosphatase, Non-Receptor Type 6/metabolism , Protozoan Proteins/metabolism , Protozoan Proteins/genetics , Humans , Mice , rho-Associated Kinases/metabolism , Toxoplasmosis/metabolism , Toxoplasmosis/parasitology , Toxoplasmosis/pathology , Mice, Inbred C57BL
6.
Res Sq ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38978596

ABSTRACT

The obligate intracellular parasite Toxoplasma gondii causes life-threatening toxoplasmosis to immunocompromised individuals. The pathogenesis of Toxoplasma relies on its swift dissemination to the central nervous system through a 'Trojan Horse' mechanism using infected leukocytes as carriers. Previous work found TgWIP, a protein secreted from Toxoplasma, played a role in altering the actin cytoskeleton and promoting cell migration in infected dendritic cells (DCs). However, the mechanism behind these changes was unknown. Here, we report that TgWIP harbors two SH2-binding motifs that interact with tyrosine phosphatases Shp1 and Shp2, leading to phosphatase activation. DCs infected with Toxoplasma exhibited hypermigration, accompanying enhanced F-actin stress fibers and increased membrane protrusions such as filopodia and pseudopodia. By contrast, these phenotypes were abrogated in DCs infected with Toxoplasma expressing a mutant TgWIP lacking the SH2-binding motifs. We further demonstrated that the Rho-associated kinase (Rock) is involved in the induction of these phenotypes, in a TgWIP-Shp1/2 dependent manner. Collectively, the data uncover a molecular mechanism by which TgWIP modulates the migration dynamics of infected DCs in vitro.

7.
Animals (Basel) ; 14(13)2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38997977

ABSTRACT

Food waste is a common issue arising from grinding of food by experimental animals, leading to excessive food scraps falling into cages. In the wild, animals grind food by gnawing vegetation and seeds, potentially damaging the ecological environment. However, limited ecology studies have focused on food grinding behavior since the last century, with even fewer on rodent food grinding, particularly recently. Although food grinding's function is partially understood, its biological purposes remain under-investigated and driving factors unclear. This review aims to explain potential causes of animal food grinding, identify influencing factors, and discuss contexts and limitations. Specifically, we emphasize recent progress on gut microbiota significance for food grinding. Moreover, we show abnormal food grinding is determined by degree of excess normal behavior, emphasizing food grinding is not meaningless. Findings from this review promote comprehensive research on the myriad factors, multifaceted roles, and intricate evolution underlying food grinding behavior, benefiting laboratory animal husbandry and ecological environment protection, and identifying potential physiological benefits yet undiscovered.

9.
Environ Pollut ; 357: 124412, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38908678

ABSTRACT

The transport and retention data in environmental media are indispensable for the hazard evaluations of graphene materials. Due to the complexity of soil, the transport of graphene is hard to quantify without isotope labeling. Herein, we developed 2D Raman mapping as a label-free technique to quantify graphene oxide (GO) in soil. After pre-treatment by hydrazine hydrate to quench its fluorescence, the quantification of GO in soil was achieved in the range of 0.1-1000 mg/L by measuring the average G-band intensity. In column transport experiment, the transport and retention of GO in soil depended on the solution chemistry. Lower pH and higher ionic strength hindered the transport of GO. In particular, Ca2+ showed the most obvious retardation on the transport of GO. GO enriched in the surficial soil layer by several folds of the initial concentrations, and higher GO concentration led to more surficial enrichment. The sowing manner of seeds affected the soil enrichment of GO, too. The surficial enrichment of GO reduced its direct contact with seedling roots, resulting in the alleviation of GO toxicity. Our results provided a facile method to study the environmental behaviors of graphene and highlighted the crucial impacts of environmental media on the graphene toxicity.

10.
Sci Rep ; 14(1): 14796, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38926523

ABSTRACT

In traditional von Neumann computing architecture, the efficiency of the system is often hindered by the data transmission bottleneck between the processor and memory. A prevalent approach to mitigate this limitation is the use of non-volatile memory for in-memory computing, with spin-orbit torque (SOT) magnetic random-access memory (MRAM) being a leading area of research. In this study, we numerically demonstrate that a precise combination of damping-like and field-like spin-orbit torques can facilitate precessional magnetization switching. This mechanism enables the binary memristivity of magnetic tunnel junctions (MTJs) through the modulation of the amplitude and width of input current pulses. Building on this foundation, we have developed a scheme for a reconfigurable spintronic logic gate capable of directly implementing Boolean functions such as AND, OR, and XOR. This work is anticipated to leverage the sub-nanosecond dynamics of SOT-MRAM cells, potentially catalyzing further experimental developments in spintronic devices for in-memory computing.

11.
J Neuroophthalmol ; 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38829714

ABSTRACT

BACKGROUND: The coronavirus disease (COVID-19) pandemic broke out in March 2020, causing tremendous damage to public health and more than 6 million deaths. After authorization for the emergency use of COVID-19 vaccines, various adverse events have been reported, including optic neuritis. COVID-19 vaccination was implemented in Taiwan in March 2021. METHODS: We report patients who developed optic neuritis after COVID-19 vaccination at one university-affiliated tertiary hospital, between March 2021 and December 2022. We also provided a literature review of optic neuritis cases after COVID-19 vaccination. RESULTS: Five patients who developed optic neuritis after COVID-19 vaccination have been identified. Four brands of vaccine used were as follows: Moderna, Pfizer-BioNTech, Medigen, and Oxford AstraZeneca. Optic neuritis developed after the first dose of vaccination in 4 patients, whereas in 1 patient, it developed after the second shot. In the 3 patients with poor initial visual acuity, intravenous methylprednisolone pulse therapy achieved substantial improvement. CONCLUSIONS: Optic neuritis is a rare but potentially vision-threatening adverse effect of COVID-19 vaccination. We suggest early diagnosis and treatment to maximize visual outcomes.

12.
Plant Commun ; : 101000, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38859586

ABSTRACT

Hybrid crops often exhibit increased yield and greater resilience, yet the genomic mechanism(s) underlying hybrid vigor or heterosis remain unclear, hindering our ability to predict the expression of phenotypic traits in hybrid breeding. Here, we generated haplotype-resolved T2T genome assemblies of two pear hybrid varieties 'Yuluxiangli' (YLX) and 'Hongxiangsu' (HXS) that share the same maternal parent, but differ in their paternal parents. We then used these assemblies to explore genome-scale landscape of allele-specific expression and create a pangenome graph for pear. Allele specific expression (ASE) was observed for close to 6000 genes in both hybrid cultivars. A subset of ASEGs related to fruit quality including sugar, organic acid and cuticular wax were identified, suggesting their important contributions to heterosis. Specifically, Ma1, a gene regulating fruit acidity, was absent in the paternal haplotypes of HXS and YLX. Further, a pangenome graph was built based on our assemblies and eight published pear genomes. Resequencing data for 139 cultivated pear genotypes (including 97 genotypes sequenced here) were subsequently aligned to the pangenome graph, revealing numerous SV hotspots and selective sweeps during pear diversification. As predicted, the Ma1 allele was found to be absent in varieties with low organic acid content, an association that was functionally validated by Ma1 over-expression in pear fruit and calli. Overall, the results unraveled contributions of allele-specific expression to heterosis involving fruit quality and provided a robust pangenome reference for high resolution allele discovery and association mapping.

13.
Food Chem ; 457: 140186, 2024 Jun 23.
Article in English | MEDLINE | ID: mdl-38924911

ABSTRACT

Qu-aroma is of great significance for evaluation the quality of Daqu starter. This study aimed to decode the Qu-aroma of medium-temperature Daqu (MT-Daqu) via "top-down" and "bottom-up" approaches. Firstly, 52 aroma descriptors were defined to describe the MT-Daqu aroma by quantitative descriptive analysis. Secondly, 193 volatile organic compounds (VOCs) were identified from 42 MT-Daqu samples by HS-SPME-GC-MS, and 43 dominant VOCs were screened out by frequence of occurrence or abundance. By Thin Film (TF)-SPME-GC-O-MS, 27 odors and 90 VOCs were detected in MT-Daqu mixture, and 14 odor-active VOCs were screened out by odor intensity. Thirdly, a five-level MT-Daqu aroma wheel was constructed by matching 52 aroma descriptors and 37 aroma-active VOCs. Finally, Qu-aroma of MT-Daqu was reconstructed with 37 aroma-active VOCs and evaluated by omission experiments. Hereinto, 26 key aroma-active VOCs were determined by OAV value ≥1, including isovaleric acid, 1-hexanol, isovaleraldehyde, 2-octanone, trimethylpyrazine, γ-nonalactone, 4-vinylguaiacol, etc.

14.
Br J Clin Pharmacol ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38925586

ABSTRACT

AIMS: The recommended dosage of pegylated recombinant human granulocyte-colony stimulating factor (PEG-rhG-CSF) for Western chemotherapy patients is 6 mg per cycle. However, for Eastern Asians, the optimal dose remains unknown. METHODS: This open-label, randomized, non-inferiority trial (NCT05283616) enrolled Chinese female breast cancer patients receiving adjuvant chemotherapy. Participants were randomized to receive either 3 or 6 mg of PEG-rhG-CSF per cycle, stratified by body weight (BW; ≤60 kg vs. >60 kg). The primary endpoint was timely absolute neutrophil count (ANC) recovery before the second cycle of chemotherapy. RESULTS: A total of 122 patients were randomized and 116 were included for efficacy analyses. The timely ANC recovery rate in the 3 mg arm was 89.8%, compared to 93.0% in the 6 mg arm (one-sided 95% confidence interval [CI] lower limit for difference: -11.7%), meeting the prespecified non-inferiority margin of 15%. The rate was 93.3% with PEG-rhG-CSF 3 mg and 96.6% with 6 mg in patients with BW ≤ 60 kg, and 86.2% and 89.3%, respectively, in those with BW > 60 kg. Although the incidence of severe neutropenia was similar across arms, the occurrence of excessively high ANC and white blood cell counts was higher in the 6 mg arm. No grade ≥3 adverse events related to PEG-rhG-CSF occurred. CONCLUSION: Three milligrams of PEG-rhG-CSF per cycle provided non-inferior neutrophil protection and attenuated neutrophil overshoot compared to 6 mg doses. This low-dose regimen could be a new supportive care option for Chinese breast cancer patients receiving anthracycline-based adjuvant chemotherapy.

15.
Ibrain ; 10(2): 197-216, 2024.
Article in English | MEDLINE | ID: mdl-38915944

ABSTRACT

This review comprehensively assesses the epidemiology, interaction, and impact on patient outcomes of perioperative sleep disorders (SD) and perioperative neurocognitive disorders (PND) in the elderly. The incidence of SD and PND during the perioperative period in older adults is alarmingly high, with SD significantly contributing to the occurrence of postoperative delirium. However, the clinical evidence linking SD to PND remains insufficient, despite substantial preclinical data. Therefore, this study focuses on the underlying mechanisms between SD and PND, underscoring that potential mechanisms driving SD-induced PND include uncontrolled central nervous inflammation, blood-brain barrier disruption, circadian rhythm disturbances, glial cell dysfunction, neuronal and synaptic abnormalities, impaired central metabolic waste clearance, gut microbiome dysbiosis, hippocampal oxidative stress, and altered brain network connectivity. Additionally, the review also evaluates the effectiveness of various sleep interventions, both pharmacological and nonpharmacological, in mitigating PND. Strategies such as earplugs, eye masks, restoring circadian rhythms, physical exercise, noninvasive brain stimulation, dexmedetomidine, and melatonin receptor agonists have shown efficacy in reducing PND incidence. The impact of other sleep-improvement drugs (e.g., orexin receptor antagonists) and methods (e.g., cognitive-behavioral therapy for insomnia) on PND is still unclear. However, certain drugs used for treating SD (e.g., antidepressants and first-generation antihistamines) may potentially aggravate PND. By providing valuable insights and references, this review aimed to enhance the understanding and management of PND in older adults based on SD.

16.
Anat Sci Educ ; 2024 Jun 09.
Article in English | MEDLINE | ID: mdl-38853404

ABSTRACT

Dental anatomy education for dental technology students should be developed in alignment with digital dental laboratory practices. We hypothesized that a virtually assisted sketching-based dental anatomy teaching module could improve students' acquisition of skills essential for digital restoration design. The second-year dental technology curriculum included a novel virtual technology-assisted sketching-based module for dental anatomy education. Pre- and post-course assessments evaluated students' skill sets and knowledge bases. Computer-aided design (CAD) scores were analyzed after one year to assess how the skills students developed through this module impacted their subsequent CAD performance. Participants who undertook the dental sketching-based teaching module demonstrated significantly improved theoretical knowledge of dental anatomy, dental aesthetic perception, and spatial reasoning skills. A partial least squares structural equation model indicated that the positive effects of this module on subsequent CAD performance were indirectly mediated by dental aesthetic perception, spatial reasoning, and practice time. A virtually assisted sketching-based dental anatomy teaching module significantly improved students' acquisition of skills and knowledge and positively mediated dental technology students' CAD performance.

17.
Nat Commun ; 15(1): 5071, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38871718

ABSTRACT

To emulate the ordered arrangement of monomer units found in natural macromolecules, single-unit monomer insertion (SUMI) have emerged as a potent technique for synthesizing sequence-controlled vinyl polymers. Specifically, numerous applications necessitate vinyl polymers encompassing both radically and cationically polymerizable monomers, posing a formidable challenge due to the distinct thiocarbonylthio end-groups required for efficient control over radical and cationic SUMIs. Herein, we present a breakthrough in the form of interconvertible radical and cationic SUMIs achieved through the manipulation of thiocarbonylthio end-groups. The transition from a trithiocarbonate (for radical SUMI) to a dithiocarbamate (for cationic SUMI) is successfully accomplished via a radical-promoted reaction with bis(thiocarbonyl) disulfide. Conversely, the reverse transformation utilizes the reaction between dithiocarbamate and bistrithiocarbonate disulfide under a cationic mechanism. Employing this strategy, we demonstrate a series of synthetic examples featuring discrete oligomers containing acrylate, maleimide, vinyl ether, and styrene, compositions unattainable through the SUMI of a single mechanism alone.

18.
Anal Chem ; 96(25): 10416-10425, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38861486

ABSTRACT

5,10-Dimethyl-5,10-dihydrophenazine (MP) is utilized as an effective auxochrome, leveraging its highly conjugated structure to enhance the photophysical and photochemical properties of fluorophores. As illustrated in the difluoride-boron complex and coumarin fluorophores, the extensive conjugation of MP auxochrome substantially red-shifts the absorption/emission wavelengths and increases Stokes shift due to the intensified intramolecular charge transfer effect; notably, MP auxochrome effectively improves fluorophores' photostability by mitigating photooxidative reactions through enhanced electron density delocalization on nitrogen atoms and increased ionization potential. Importantly, MP-based fluorophores demonstrate applicability in stimulated emission depletion nanomicroscopy, showcasing their utility in lipid droplet labeling.

19.
Anal Chem ; 96(27): 11061-11067, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38922611

ABSTRACT

Amplified nanoprobes based on hybridization chain reaction (HCR) have been widely developed for the detection of intracellular low abundance mRNA. However, the formed chain-like assembly decorated with fluorophore would be degraded rapidly by endogenous enzyme, resulting in failure of the long-term fluorescence imaging. To address this issue, herein, a composite signal-amplifying strategy that integrates HCR into protein-binding signal amplification (HPSA) was communicated for the in situ imaging of mRNA by avoiding signal fluctuation. Different from conventional HCR-based nanoprobes (HCR-nanoprobe), the HCR was used as the signal-triggered mode and the amplifying signal generated from in situ fluorophore-protein binding in cells, which can maintain high stability of the signal for a long time. As a proof-of-principle, a nanobeacon based on HPSA (HPSA-nanobeacon) was constructed to detect TK1 mRNA. Taking advantage of the double signal-amplifying mode, the endogenous TK1 mRNA was sensitively detected and the fluorescence signal was maintained for more than 8 h in HepG2 cells. The attempt in this work provides a new option to the current signal-amplifying strategy for sensing nucleic acid targets with high stability, significantly enhancing the acquisition of intracellular molecular information.


Subject(s)
Nucleic Acid Hybridization , RNA, Messenger , Humans , RNA, Messenger/analysis , RNA, Messenger/metabolism , RNA, Messenger/genetics , Hep G2 Cells , Optical Imaging , Fluorescent Dyes/chemistry , Protein Binding , Nucleic Acid Amplification Techniques/methods , Thymidine Kinase
20.
Nanomaterials (Basel) ; 14(12)2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38921925

ABSTRACT

This study aims to enhance the optical and thermal properties of cesium-based perovskite nanocrystals (NCs) through surface passivation with organic sulfonate (or sulfonic acid) ligands. Four different phenylated ligands, including sodium ß-styrenesulfonate (SbSS), sodium benzenesulfonate (SBS), sodium p-toluenesulfonate (SPTS), and 4-dodecylbenzenesulfonic acid (DBSA), were employed to modify blue-emitting CsPbBr1.5Cl1.5 perovskite NCs, resulting in improved size uniformity and surface functionalization. Transmission electron microscopy and X-ray photoelectron spectroscopy confirmed the successful anchoring of sulfonate or sulfonic acid ligands on the surface of perovskite NCs. Moreover, the photoluminescence quantum yield increased from 32% of the original perovskite NCs to 63% of the SPTS-modified ones due to effective surface passivation. Time-resolved photoluminescence decay measurements revealed extended PL lifetimes for ligand-modified NCs, indicative of reduced nonradiative recombination. Thermal stability studies demonstrated that the SPTS-modified NCs retained nearly 80% of the initial PL intensity when heated at 60 °C for 10 min, surpassing the performance of the original NCs. These findings emphasize the optical and thermal stability enhancement of cesium-based perovskite NCs through surface passivation with suitable sulfonate ligands.

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