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1.
Cell Rep ; 43(5): 114180, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38733581

ABSTRACT

Macrophage activation is a hallmark of atherosclerosis, accompanied by a switch in core metabolism from oxidative phosphorylation to glycolysis. The crosstalk between metabolic rewiring and histone modifications in macrophages is worthy of further investigation. Here, we find that lactate efflux-associated monocarboxylate transporter 4 (MCT4)-mediated histone lactylation is closely related to atherosclerosis. Histone H3 lysine 18 lactylation dependent on MCT4 deficiency activated the transcription of anti-inflammatory genes and tricarboxylic acid cycle genes, resulting in the initiation of local repair and homeostasis. Strikingly, histone lactylation is characteristically involved in the stage-specific local repair process during M1 to M2 transformation, whereas histone methylation and acetylation are not. Gene manipulation and protein hydrolysis-targeted chimerism technology are used to confirm that MCT4 deficiency favors ameliorating atherosclerosis. Therefore, our study shows that macrophage MCT4 deficiency, which links metabolic rewiring and histone modifications, plays a key role in training macrophages to become repair and homeostasis phenotypes.

2.
EBioMedicine ; 104: 105152, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38728838

ABSTRACT

BACKGROUND: The tumour stroma is associated with unfavourable prognosis in diverse solid tumours, but its prognostic and predictive value in bladder cancer (BCa) is unclear. METHODS: In this multicentre, retrospective study, we included 830 patients with BCa from six independent cohorts. Differences in overall survival (OS) and cancer-specific survival (CSS) were investigated between high-tumour stroma ratio (TSR) and low-TSR groups. Multi-omics analyses, including RNA sequencing, immunohistochemistry, and single-cell RNA sequencing, were performed to study stroma-immune interactions. TSR prediction models were developed based on pelvic CT scans, and the best performing model was selected based on receiver operator characteristic analysis. FINDINGS: Compared to low-TSR tumours, high-TSR tumours were significantly associated with worse OS (HR = 1.193, 95% CI: 1.046-1.361, P = 0.008) and CSS (HR = 1.337, 95% CI: 1.139-1.569, P < 0.001), and lower rate of pathological complete response (pCR) to neoadjuvant chemotherapy (NAC). High-TSR tumours exhibited higher infiltration of immunosuppressive cells, including Tregs and tumour-associated neutrophils, while low-TSR tumours exhibited higher infiltration of immune-activating cells such as CD8+ Teff and XCR1+ dendritic cells. The TSR prediction model was developed by combining the intra-tumour and tumour base radiomics features, and showed good performance to predict high-TSR, as indicted by area under the curve of 0.871 (95% CI: 0.821-0.921), 0.821 (95% CI: 0.731-0.911), and 0.801 (95% CI: 0.737-0.865) in the training, internal validation, and external validation cohorts, respectively. In patients with low predicted TSR, 92.3% (12/13) achieved pCR, while only 35.3% (6/17) of patients with high predicted TSR achieved pCR. INTERPRETATION: The tumour stroma was found to be significantly associated with clinical outcomes in patients with BCa as a result of tumour stroma-immune interactions. The radiomics prediction model provided non-invasive evaluation of TSR and was able to predict pCR in patients receiving NAC for BCa. FUNDING: This work was supported by National Natural Science Foundation of China (Grant No. 82373254 and 81961128027), Guangdong Provincial Natural Science Foundation (Grant No. 2023A1515010258), Science and Technology Planning Project of Guangdong Province (Grant No. 2023B1212060013). Science and Technology Program of Guangzhou (SL2022A04J01754), Sun Yat-Sen Memorial Hospital Clinical Research 5010 Program (Grant No. SYS-5010Z-202401).

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124339, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38696995

ABSTRACT

The FDA (Food and Drug Administration, (USA)) lists ZnO as a material that is widely acknowledged to be safe. ZnO NPs with a range of tiny particle sizes were made using the precipitation process. ZnO nanoparticles' surface is embellished with a tripodal sensor containing naphthol units. The assembly with the same receptor decorated on ZnO NPs is contrasted with the cation detection capabilities of the purified tripodal receptor. The UV-visible spectrophotometric analysis was conducted to study the state transitions of the receptor and the decorated ZnO receptor. A positive selectivity to Al3+ cations is determined by the fluorescence study under ideal circumstances. The particle size and surface morphologies are determined by DLS and SEM analysis for the same receptor - TP1 and embellished with a tripodal receptor TP2. Using a fluorescence switch-on Photoinduced Electron Transfer (PET) mechanism, the receptor coated on ZnO detects the presence of Al3+ ions with specificity. The binding constant value was determined using the B-H plot equation. Binding stoichiometry for [TP1-Al3+, TP2-Al3+] showed a 1:1 ratio. The fluorescence switches ON-OFF process of the ZnO surface adorned - TP2 with Tripodal receptor- TP1 was used to create molecular logic gates, which can function as a module for sensors and molecular switches. The addition of Na2EDTA in the solution of the [TP1; TP2 - Al3+] complex resulted in a noticeable reduction in the emission of fluorescence. This finding offers compelling support for the reversibility of the chemosensor. To enable the practical application of this sensor, we have developed a cassette containing receptors TP1 and TP2. Successfully, it can detect Al3+ metal ions. We performed a comprehensive assessment of the dependability and appropriateness of our approach in measuring the concentration of Al3+ ions in wastewater produced by important industrial procedures.

4.
Brain Res ; 1838: 148977, 2024 May 04.
Article in English | MEDLINE | ID: mdl-38705556

ABSTRACT

OBJECTIVE: Previous research has suggested a connection between major depressive disorder (MDD) and certain comorbidities, including gastrointestinal issues, thyroid dysfunctions, and glycolipid metabolism abnormalities. However, the relationships between these factors and asymmetrical alterations in functional connectivity (FC) in adults with MDD remain unclear. METHOD: We conducted a study on a cohort of 42 MDD patients and 42 healthy controls (HCs). Participants underwent comprehensive clinical assessments, including evaluations of blood lipids and thyroid hormone levels, as well as resting-state functional magnetic resonance imaging (Rs-fMRI) scans. Data analysis involved correlation analysis to compute the parameter of asymmetry (PAS) for the entire brain's functional connectome. We then examined the interrelationships between abnormal PAS regions in the brain, thyroid hormone levels, and blood lipid levels. RESULTS: The third-generation ultra-sensitive thyroid stimulating hormone (TSH3UL) level was found to be significantly lower in MDD patients compared to HCs. The PAS score of the left inferior frontal gyrus (IFG) decreased, while the bilateral posterior cingulate cortex (Bi-PCC) PAS increased in MDD patients relative to HCs. Notably, the PAS score of the left IFG negatively correlated with both TSH and total cholesterol (CHOL) levels. However, these correlations lose significance after the Bonferroni correction. CONCLUSION: MDD patients demonstrated abnormal asymmetry in resting-state FC (Rs-FC) within the fronto-limbic system, which may be associated with CHOL and thyroid hormone levels.

5.
J Pharm Biomed Anal ; 245: 116161, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38714135

ABSTRACT

In this study, Fe3O4@ZnCr-layered double hydroxide/zeolitic imidazolate frameworks-8 (MLDH/ZIF-8) magnetically functionalized composites were synthesized by co-precipitation and in situ growth based on the advantages of LDHs and ZIF-8 using Fe3O4 nanoparticles as a magnetic substrate to obtain adsorbents with excellent performance. Moreover, the composite was used for the efficient enrichment of flavonoids in Chinese herbal medicines. The internal structures and surface properties were characterized by SEM, Fourier transform infrared spectroscopy, X-ray diffraction and so on. MLDH/ZIF-8 exhibited a large specific surface area and good paramagnetic properties. The MLDH/ZIF-8 magnetic composite was used as a magnetic solid-phase extraction (MSPE) adsorbent, and a MLDH/ZIF-8 MSPE-pressurized capillary electrochromatography coupling method was developed for the separation and detection of flavonoids (luteolin, kaempferol and apigenin) in a sample of the Chinese herb Ohwia caudata (Thunberg) H. Ohashi. The relevant parameters affecting the extraction efficiency were optimized to determine the ideal conditions for MSPE. 5 mg of adsorbent in sample solution at pH 6, vortex extraction for 5 min, elution with 1.5 mL of ethyl acetate for 15 min. The method showed good linearity in the concentration range of 3-50 µg mL-1 with correlation coefficients of 0.9934-0.9981, and displayed a relatively LODs of 0.07-0.09 µg mL-1. The spiked recoveries of all analytes ranged from 84.5% to 122.0% with RSDs (n=3) between 4.5% and 7.7%. This method is straightforward and efficient, with promising potential in the separation and analysis of active ingredients in various Chinese herbal medicines.


Subject(s)
Drugs, Chinese Herbal , Flavonoids , Hydroxides , Solid Phase Extraction , Flavonoids/isolation & purification , Flavonoids/analysis , Flavonoids/chemistry , Solid Phase Extraction/methods , Hydroxides/chemistry , Drugs, Chinese Herbal/chemistry , Adsorption , Magnetite Nanoparticles/chemistry , Metal-Organic Frameworks/chemistry , Spectroscopy, Fourier Transform Infrared/methods
6.
Schizophr Res ; 267: 519-527, 2024 May.
Article in English | MEDLINE | ID: mdl-38704344

ABSTRACT

BACKGROUND: Previous investigations have revealed substantial differences in neuroimaging characteristics between healthy controls (HCs) and individuals diagnosed with schizophrenia (SCZ). However, we are not entirely sure how brain activity links to symptoms in schizophrenia, and there is a need for reliable brain imaging markers for treatment prediction. METHODS: In this longitudinal study, we examined 56 individuals diagnosed with 56 SCZ and 51 HCs. The SCZ patients underwent a three-month course of antipsychotic treatment. We employed resting-state functional magnetic resonance imaging (fMRI) along with fractional Amplitude of Low Frequency Fluctuations (fALFF) and support vector regression (SVR) methods for data acquisition and subsequent analysis. RESULTS: In this study, we initially noted lower fALFF values in the right postcentral/precentral gyrus and left postcentral gyrus, coupled with higher fALFF values in the left hippocampus and right putamen in SCZ patients compared to the HCs at baseline. However, when comparing fALFF values in brain regions with abnormal baseline fALFF values for SCZ patients who completed the follow-up, no significant differences in fALFF values were observed after 3 months of treatment compared to baseline data. The fALFF values in the right postcentral/precentral gyrus and left postcentral gyrus, and the left postcentral gyrus were useful in predicting treatment effects. CONCLUSION: Our findings suggest that reduced fALFF values in the sensory-motor networks and increased fALFF values in the limbic system may constitute distinctive neurobiological features in SCZ patients. These findings may serve as potential neuroimaging markers for the prognosis of SCZ patients.


Subject(s)
Antipsychotic Agents , Limbic System , Magnetic Resonance Imaging , Schizophrenia , Humans , Schizophrenia/physiopathology , Schizophrenia/diagnostic imaging , Schizophrenia/drug therapy , Male , Female , Adult , Antipsychotic Agents/pharmacology , Limbic System/diagnostic imaging , Limbic System/physiopathology , Longitudinal Studies , Young Adult , Treatment Outcome , Outcome Assessment, Health Care , Middle Aged , Support Vector Machine
7.
Small ; : e2310678, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38708801

ABSTRACT

The quality requirements of graphene depend on the applications. Some have a high tolerance for graphene quality and even require some defects, while others require graphene as perfect as possible to achieve good performance. So far, synthesis of large-area graphene films by chemical vapor deposition of carbon precursors on metal substrates, especially on Cu, remains the main way to produce high-quality graphene, which has been significantly developed in the past 15 years. However, although many prototypes are demonstrated, their performance is still more or less far from the theoretical property limit of graphene. This review focuses on how to make super graphene, namely graphene with a perfect structure and free of contaminations. More specially, this study focuses on graphene synthesis on Cu substrates. Typical defects in graphene are first discussed together with the formation mechanisms and how they are characterized normally, followed with a brief review of graphene properties and the effects of defects. Then, the synthesis progress of super graphene from the aspects of substrate, grain size, wrinkles, contamination, adlayers, and point defects are reviewed. Graphene transfer is briefly discussed as well. Finally, the challenges to make super graphene are discussed and a strategy is proposed.

8.
Adv Colloid Interface Sci ; 328: 103179, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38754212

ABSTRACT

Membrane technology has emerged as a crucial method for obtaining clean water from unconventional sources in the face of water scarcity. It finds wide applications in wastewater treatment, advanced treatment, and desalination of seawater and brackish water. However, membrane fouling poses a huge challenge that limits the development of membrane-based water treatment technologies. Characterizing the dynamics of membrane fouling is crucial for understanding its development, mechanisms, and effective mitigation. Instrumental techniques that enable in situ or real-time characterization of the dynamics of membrane fouling provide insights into the temporal and spatial evolution of fouling, which play a crucial role in understanding the fouling mechanism and the formulation of membrane control strategies. This review consolidates existing knowledge about the principal advanced instrumental analysis technologies employed to characterize the dynamics of membrane fouling, in terms of membrane structure, morphology, and intermolecular forces. Working principles, applications, and limitations of each technique are discussed, enabling researchers to select appropriate methods for their specific studies. Furthermore, prospects for the future development of dynamic characterization techniques for membrane fouling are discussed, underscoring the need for continued research and innovation in this field to overcome the challenges posed by membrane fouling.

9.
Chemistry ; : e202400803, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38752562

ABSTRACT

To meet the demand for higher energy density in lithium-ion batteries and expand their application range, coupling lithium metal anodes with high-voltage cathodes is an ideal solution. However, the compatibility between lithium metal batteries and electrolytes affects their applicability. In this study, proposes a locally concentrated electrolyte based on ethyl acetate (EA) as the solvent, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as the lithium salt, and lithium difluorooxoborate (LiDFOB) as a sacrificial agent to enhance the low-temperature and high-voltage endurance of Li//Lithium cobalt oxide (LCO) batteries. The Li//LCO battery can operate within the voltage range of 3 to 4.5 V, with an initial discharge specific capacity of 174.5 mAh g-1 at 20 oC. At -40 oC, after 200 cycles, the capacity retention rate is 87.7%. It can operate under extreme conditions of -70 oC, with a discharge specific capacity of 112.6 mAh g-1. Additionally, LCO//HC batteries using this electrolyte demonstrate excellent performance. Present work provides a new perspective for the optimization of electrolytes for low-temperature lithium-ion batteries.

10.
Minerva Urol Nephrol ; 76(2): 241-246, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38742557

ABSTRACT

BACKGROUND: To evaluate the feasibility and safety of dual-console telesurgery with the new KangDuo system in an animal experiment and clinical study. METHODS: Six canine models were performed radical prostatectomy with dual-console KanDuo surgical robot-1500 (KD-SR-1500-RARP). The perioperative outcomes, physical and mental workload of the surgeon were collected. Physical workload was evaluated with surface electromyography. Mental workload was evaluated with NASA-TLX. After conducting animal experiments to verify safety of dual-console KD-SR-1500-RARP, we conducted the clinical trial using 5G and wired networks. RESULTS: In the animal experiment, all surgeries were performed successfully. The operative time was 80.2±32.1 min. The docking time was 2.4±0.5 min. The console time was 49.7±25.3 min. There were no perioperative complications or equipment related adverse events. All dogs can micturate after catheter removal at one week postoperatively. The mental workload was at a low level (a scale ranging from 0 to 60), which scored 15.7±6.9. Among the eight recorded muscles, the fatigue degree of the right radial flexor and left biceps was the highest two (iEMG, resection, 299.8±344 uV, 109.9±16.9 uV; suture, 849.4±1252.5 uV, 423.1±621.3 uV, respectively). In the clinical study, the console time was 136 min. The mean latency time was ≤200 ms. The data pocket loss was <1%. The operation was successfully completed without malfunctions occurring throughout the entire process. CONCLUSIONS: Dual-console telesurgery with the KD-SR-1500 system was shown to be feasible and safe in radical prostatectomy using 5G and wired networks.


Subject(s)
Feasibility Studies , Prostatectomy , Robotic Surgical Procedures , Animals , Dogs , Robotic Surgical Procedures/methods , Robotic Surgical Procedures/adverse effects , Male , Prostatectomy/methods , Prostatectomy/adverse effects , Humans , Middle Aged , Equipment Design , Operative Time , Aged , Electromyography , Telemedicine/methods
11.
J Endourol ; 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38623792

ABSTRACT

PURPOSE: To investigate the feasibility, safety, and efficacy of the KangDuo Surgical Robot-01 (KD-SR-01) system for robot-assisted radical nephroureterectomy (UTUC). MATERIALS AND METHODS: This prospective, single-center, single-arm clinical study of patients with UTUC was conducted from August 2022 to July 2023 using the KD-SR-01 system. The perioperative and follow-up data were prospectively recorded. The National Aeronautics and Space Administration Task Load Index was calculated to present ergonomics. The technique was described in detail. RESULTS: A total of 13 patients underwent RARNU. None of the cases conversed to laparoscopic surgery or open surgery. The median docking time and console time were 524 (range, 139-963) seconds and 102.2 (range, 55.3-249.3) minutes, respectively. The median estimated blood loss was 40 (range, 10-100) ml. None of the patients required intraoperative blood transfusion. The median postoperative hospital stay was 4 (range, 2-7) days. Intraoperative or postoperative complications (Clavien-Dindo grade I) occurred in 9 patients. The surgeon Task Load Index global score achieved 1.05±1.86. Three patients received the single-docking technique, demonstrating similar perioperative results compared to patients with re-docking. CONCLUSIONS: The KD-SR-01 system was feasible, safe, and effective for robot-assisted radical nephroureterectomy.

13.
Cancer Invest ; : 1-19, 2024 Apr 21.
Article in English | MEDLINE | ID: mdl-38644691

ABSTRACT

This study aims to develop a prognostic signature based on m6A-related lncRNAs for clear cell renal cell carcinoma (ccRCC). Differential expression analysis and Pearson correlation analysis were used to identify m6A-related lncRNAs associated with patient outcomes in The Cancer Genome Atlas (TCGA) database. Our approach led to the development of an m6A-related lncRNA risk score (MRLrisk), formulated using six identified lncRNAs: NFE4, AL008729.2, AL139123.1, LINC02154, AC124854.1 and ARHGAP31-AS1. Higher MRLrisk was identified as a risk factor for patients' prognosis in ccRCC. Furthermore, an MRLrisk-based nomogram was developed and demonstrated as a reliable tool for prognosis prediction in ccRCC. Enrichment analysis and tumor mutation signature studies were conducted to investigate MRLrisk-related biological phenotypes. The tumor immune dysfunction and exclusion (TIDE) score was employed to infer patients' response to immunotherapy, indicating a negative correlation between high MRLrisk and immunotherapy response. Our focus then shifted to LINC02154 for deeper exploration. We assessed LINC02154 expression in 28 ccRCC/normal tissue pairs and 3 ccRCC cell lines through quantitative real-time polymerase chain reaction (qRT-PCR). Functional experiments, including EdU incorporation, flow cytometry and transwell assays, were performed to assess the role of LINC02154 in ccRCC cell functions, discovering that its downregulation hinders cancer cell proliferation and migration. Furthermore, the influence of LINC02154 on ccRCC cells' sensitivity to Sunitinib was explored using CCK-8 assays, demonstrating that decreased LINC02154 expression increases Sunitinib sensitivity. In summary, this study successfully developed an MRLrisk model with significant prognostic value for ccRCC and established LINC02154 as a critical biomarker and prospective therapeutic target in ccRCC management.

14.
Biochem Biophys Res Commun ; 715: 149979, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38678779

ABSTRACT

Endothelial dysfunction is an initiating factor in atherosclerosis. Endothelial cells (ECs) are constantly subject to blood flow shear stress, and atherosclerotic plaques tend to occur in aortic bends or bifurcations impaired by low oscillatory shear stress (OSS). However, the mechanism that how OSS affects the initiation and progression of atherosclerosis remains to be explored. Here, we first reported that OSS can promote endothelial dysfunction and atherogenesis in vivo and in vitro by activating STING pathway. Mechanistically, at atherosclerosis-prone areas, OSS caused mitochondria damage in ECs, leading to the leakage of mitochondrial DNA (mtDNA) into the cytoplasm. The cytoplasmic mtDNA was recognized by cGAS to produce cGAMP, activating the STING pathway and leading to endothelial senescence, which resulted in endothelial dysfunction and atherosclerosis. We found that STING was activated in plaques of atherosclerotic patients and in aortic arch ECs of high-fat diet (HFD)-fed ApoeKO mice, as well as in ECs exposed to OSS. STING-specific deficiency in ECs attenuates endothelial senescence and resulted in a significant reduction in aortic arch plaque area in HFD-fed ApoeKO mice. Consistently, specific deficiency or pharmacological inhibition of STING attenuated OSS-induced senescence and endothelial dysfunction. Pharmacological depletion of mtDNA ameliorated OSS-induced senescence and endothelial dysfunction. Taken together, our study linked hemodynamics and endothelial senescence, and revealed a novel mechanism by which OSS leads to endothelial dysfunction. Our study provided new insights into the development of therapeutic strategies for endothelial senescence and atherosclerosis.


Subject(s)
Atherosclerosis , Cellular Senescence , DNA, Mitochondrial , Endothelial Cells , Membrane Proteins , Mice, Inbred C57BL , Stress, Mechanical , Atherosclerosis/metabolism , Atherosclerosis/pathology , Atherosclerosis/genetics , Animals , Membrane Proteins/metabolism , Membrane Proteins/genetics , Humans , DNA, Mitochondrial/genetics , DNA, Mitochondrial/metabolism , Mice , Endothelial Cells/metabolism , Endothelial Cells/pathology , Male , Endothelium, Vascular/metabolism , Endothelium, Vascular/pathology , Mitochondria/metabolism , Mitochondria/pathology , Diet, High-Fat , Cells, Cultured
15.
Magn Reson Imaging ; 110: 86-95, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38631533

ABSTRACT

Segmentation of cerebral vasculature on MR vascular images is of great significance for clinical application and research. However, the existing cerebrovascular segmentation approaches are limited due to insufficient image contrast and complicated algorithms. This study aims to explore the potential of the emerging four-dimensional arterial spin labeling magnetic resonance angiography (4D ASL-MRA) technique for fast and accurate cerebrovascular segmentation with a simple machine-learning approach. Nine temporal features were extracted from the intensity-time signal of each voxel, and eight spatial features from the neighboring voxels. Then, the unsupervised outlier detection algorithm, i.e. Isolation Forest, is used for segmentation of the vascular voxels based on the extracted features. The total length of the centerlines of the intracranial arterial vasculature, the dice similarity coefficient (DSC), and the average Hausdorff Distance (AVGHD) on the cross-sections of small- to large-sized vessels were calculated to evaluate the performance of the segmentation approach on 4D ASL-MRA of 18 subjects. Experiments show that the temporal information on 4D ASL-MRA can largely improve the segmentation performance. In addition, the proposed segmentation approach outperforms the traditional methods that were performed on the 3D image (i.e. the temporal average intensity projection of 4D ASL-MRA) and the previously proposed frame-wise approach. In conclusion, this study demonstrates that accurate and robust segmentation of cerebral vasculature is achievable on 4D ASL-MRA by using a simple machine-learning approach with appropriate features.


Subject(s)
Algorithms , Imaging, Three-Dimensional , Machine Learning , Magnetic Resonance Angiography , Spin Labels , Humans , Magnetic Resonance Angiography/methods , Imaging, Three-Dimensional/methods , Male , Female , Adult , Cerebral Arteries/diagnostic imaging , Image Processing, Computer-Assisted/methods , Cerebrovascular Circulation , Brain/diagnostic imaging , Brain/blood supply
17.
Sensors (Basel) ; 24(7)2024 Apr 05.
Article in English | MEDLINE | ID: mdl-38610537

ABSTRACT

Conventional spherical nucleic acid enzymes (SNAzymes), made with gold nanoparticle (AuNPs) cores and DNA shells, are widely applied in bioanalysis owing to their excellent physicochemical properties. Albeit important, the crowded catalytic units (such as G-quadruplex, G4) on the limited AuNPs surface inevitably influence their catalytic activities. Herin, a hybridization chain reaction (HCR) is employed as a means to expand the quantity and spaces of G4 enzymes for their catalytic ability enhancement. Through systematic investigations, we found that when an incomplete G4 sequence was linked at the sticky ends of the hairpins with split modes (3:1 and 2:2), this would significantly decrease the HCR hybridization capability due to increased steric hindrance. In contrast, the HCR hybridization capability was remarkably enhanced after the complete G4 sequence was directly modified at the non-sticky end of the hairpins, ascribed to the steric hindrance avoided. Accordingly, the improved SNAzymes using HCR were applied for the determination of AFB1 in food samples as a proof-of-concept, which exhibited outstanding performance (detection limit, 0.08 ng/mL). Importantly, our strategy provided a new insight for the catalytic activity improvement in SNAzymes using G4 as a signaling molecule.


Subject(s)
Metal Nanoparticles , Nucleic Acids , Aflatoxin B1 , Gold , Nucleic Acid Hybridization
18.
Proc Natl Acad Sci U S A ; 121(13): e2400584121, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38502707

ABSTRACT

When faced with starvation, the bacterium Bacillus subtilis transforms itself into a dormant cell type called a "spore". Sporulation initiates with an asymmetric division event, which requires the relocation of the core divisome components FtsA and FtsZ, after which the sigma factor σF is exclusively activated in the smaller daughter cell. Compartment-specific activation of σF requires the SpoIIE phosphatase, which displays a biased localization on one side of the asymmetric division septum and associates with the structural protein DivIVA, but the mechanism by which this preferential localization is achieved is unclear. Here, we isolated a variant of DivIVA that indiscriminately activates σF in both daughter cells due to promiscuous localization of SpoIIE, which was corrected by overproduction of FtsA and FtsZ. We propose that the core components of the redeployed cell division machinery drive the asymmetric localization of DivIVA and SpoIIE to trigger the initiation of the sporulation program.


Subject(s)
Bacillus subtilis , Bacterial Proteins , Bacillus subtilis/metabolism , Transcriptional Activation , Bacterial Proteins/metabolism , Spores, Bacterial/genetics , Spores, Bacterial/metabolism , Cell Division/genetics , Sigma Factor/genetics , Sigma Factor/metabolism
19.
J Am Chem Soc ; 146(14): 9801-9810, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38551407

ABSTRACT

The sequence-controlled assembly of nucleic acids and amino acids into well-defined superstructures constitutes one of the most revolutionary technologies in modern science. The elaboration of such superstructures from carbohydrates, however, remains elusive and largely unexplored on account of their intrinsic constitutional and configurational complexity, not to mention their inherent conformational flexibility. Here, we report the bottom-up assembly of two classes of hierarchical superstructures that are formed from a highly flexible cyclo-oligosaccharide─namely, cyclofructan-6 (CF-6). The formation of coordinative bonds between the oxygen atoms of CF-6 and alkali metal cations (i) locks a myriad of flexible conformations of CF-6 into a few rigid conformations, (ii) bridges adjacent CF-6 ligands, and (iii) gives rise to the multiple-level assembly of three extended frameworks. The hierarchical superstructures present in these frameworks have been shown to modulate their nanomechanical properties. This research highlights the unique opportunities of constructing convoluted superstructures from carbohydrates and should encourage future endeavors in this underinvestigated field of science.


Subject(s)
Carbohydrates , Metals , Metals/chemistry , Carbohydrates/chemistry , Molecular Conformation , Amino Acids
20.
Minerva Urol Nephrol ; 76(1): 97-109, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38426424

ABSTRACT

BACKGROUND: The aim of this study was to explore the feasibility of ileal ureter replacement and ileocystoplasty for the treatment of bilateral long-segment ureteral strictures combined with bladder contracture. METHODS: A retrospective review of clinical data from seven patients who underwent bilateral Ileal Ureter Replacement and ileocystoplasty from April 2019 to February 2023 was conducted. The surgeries were performed using open, laparoscopic, and robot-assisted laparoscopic approaches. Baseline characteristics, perioperative, and mid-term results of the patients were collected. Follow-up period of 3-28 months. A detailed description of the technique was reported. RESULTS: The mean age of the patients was 52.86±6.06 years. The average duration of surgery was 365±28.54 minutes, and the estimated intraoperative blood loss was 357.14±184.06 mL. The mean length of harvested ileum was 37.86±8.40 cm. The preoperative serum creatinine level was 88.02±18.05 µmol/L, postoperative day 1 creatinine level was 90.7±12.93µmol/L, postoperative 3-month creatinine level was 93.77±33.34 µmol/L, and the mean creatinine level at the last follow-up was 94.89±27.89µmol/L. The postoperative bladder capacity was 249.43±32.50 mL on average. The average length of hospital stay was 26.57±15.46 days. No complications of Clavien-Dindo grade 3 or higher were observed. During the follow-up period, no patients experienced deterioration of renal function after surgery. CONCLUSIONS: Bilateral ileal ureter replacement and ileocystoplasty are effective surgical technique for the treatment of bilateral long-segment ureteral strictures combined with bladder contracture caused by radiation therapy.


Subject(s)
Ureter , Ureteral Obstruction , Humans , Middle Aged , Ureter/surgery , Urinary Bladder/surgery , Constriction, Pathologic/surgery , Creatinine , Ureteral Obstruction/etiology , Ureteral Obstruction/surgery , Ileum/surgery
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