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1.
Foods ; 13(9)2024 Apr 30.
Article En | MEDLINE | ID: mdl-38731757

The traditional fermentation process of soy sauce employs a hyperhaline model and has a long fermentation period. A hyperhaline model can improve fermentation speed, but easily leads to the contamination of miscellaneous bacteria and fermentation failure. In this study, after the conventional koji and moromi fermentation, the fermentation broth was pasteurized and diluted, and then inoculated with three selected microorganisms including Corynebacterium glutamicum, Corynebacterium ammoniagenes, and Lactiplantibacillus plantarum for secondary fermentation. During this ten-day fermentation, the pH, free amino acids, organic acids, nucleotide acids, fatty acids, and volatile compounds were analyzed. The fermentation group inoculated with C. glutamicum accumulated the high content of amino acid nitrogen of 0.92 g/100 mL and glutamic acid of 509.4 mg/100 mL. The C. ammoniagenes group and L. plantarum group were rich in nucleotide and organic acid, respectively. The fermentation group inoculated with three microorganisms exhibited the best sensory attributes, showing the potential to develop a suitable fermentation method. The brewing speed of the proposed process in this study was faster than that of the traditional method, and the umami substances could be significantly accumulated in this low-salt fermented model (7% w/v NaCl). This study provides a reference for the low-salt and rapid fermentation of seasoning.

2.
Saf Health Work ; 15(1): 118-122, 2024 Mar.
Article En | MEDLINE | ID: mdl-38496279

To understand biosafety's current situation in laboratory animal research and risk factors affecting occupational health. Compliance surveys were conducted by questionnaire via Questionnaire Star (an application app on the Internet) in Chinese. Thirty-nine anonymous questionnaires were collected. The surveyed institution has established 24 types of ABSL (Animal Biosafety Laboratory) and biosafety management organizations and systems equipped with safety equipment. Our study also suggests that the principal of the laboratory establishment fails to perform supervision and inspection responsibilities, the inappropriate design of the animal biosafety laboratory, non-standardized personnel training and health management, non-strict waste management, and insufficient emergency management. The administrative department and work units should address certain safety and occupational health risks in laboratory animal research. The author proposes control strategies based on organizational guarantee, personnel management, emergency management, etc., to help prevent risks and ensure occupational health. Due to regional limitations and small sample size, the results may not be generalisable to all parts of the world. However, some of the key common issues may also be present in other regions, so we believe that this research still has some relevance.

3.
Osteoporos Int ; 35(6): 1049-1059, 2024 Jun.
Article En | MEDLINE | ID: mdl-38459138

PURPOSE: This study aimed to apply a newly developed semi-automatic phantom-less QCT (PL-QCT) to measure proximal humerus trabecular bone density based on chest CT and verify its accuracy and precision. METHODS: Subcutaneous fat of the shoulder joint and trapezius muscle were used as calibration references for PL-QCT BMD measurement. A self-developed algorithm based on a convolution map was utilized in PL-QCT for semi-automatic BMD measurements. CT values of ROIs used in PL-QCT measurements were directly used for phantom-based quantitative computed tomography (PB-QCT) BMD assessment. The study included 376 proximal humerus for comparison between PB-QCT and PL-QCT. Two sports medicine doctors measured the proximal humerus with PB-QCT and PL-QCT without knowing each other's results. Among them, 100 proximal humerus were included in the inter-operative and intra-operative BMD measurements for evaluating the repeatability and reproducibility of PL-QCT and PB-QCT. RESULTS: A total of 188 patients with 376 shoulders were involved in this study. The consistency analysis indicated that the average bias between proximal humerus BMDs measured by PB-QCT and PL-QCT was 1.0 mg/cc (agreement range - 9.4 to 11.4; P > 0.05, no significant difference). Regression analysis between PB-QCT and PL-QCT indicated a good correlation (R-square is 0.9723). Short-term repeatability and reproducibility of proximal humerus BMDs measured by PB-QCT (CV: 5.10% and 3.41%) were slightly better than those of PL-QCT (CV: 6.17% and 5.64%). CONCLUSIONS: We evaluated the bone quality of the proximal humeral using chest CT through the semi-automatic PL-QCT system for the first time. Comparison between it and PB-QCT indicated that it could be a reliable shoulder BMD assessment tool with acceptable accuracy and precision. This study developed and verify a semi-automatic PL-QCT for assessment of proximal humeral bone density based on CT to assist in the assessment of proximal humeral osteoporosis and development of individualized treatment plans for shoulders.


Bone Density , Cancellous Bone , Humerus , Tomography, X-Ray Computed , Humans , Bone Density/physiology , Male , Female , Middle Aged , Tomography, X-Ray Computed/methods , Aged , Reproducibility of Results , Humerus/diagnostic imaging , Humerus/physiology , Cancellous Bone/diagnostic imaging , Cancellous Bone/physiopathology , Cancellous Bone/physiology , Algorithms , Phantoms, Imaging , Adult , Osteoporosis/physiopathology , Osteoporosis/diagnostic imaging , Aged, 80 and over
5.
Behav Res Methods ; 2024 Feb 02.
Article En | MEDLINE | ID: mdl-38308148

Conditional process models, including moderated mediation models and mediated moderation models, are widely used in behavioral science research. However, few studies have examined approaches to conduct statistical power analysis for such models and there is also a lack of software packages that provide such power analysis functionalities. In this paper, we introduce new simulation-based methods for power analysis of conditional process models with a focus on moderated mediation models. These simulation-based methods provide intuitive ways for sample-size planning based on regression coefficients in a moderated mediation model as well as selected variance and covariance components. We demonstrate how the methods can be applied to five commonly used moderated mediation models using a simulation study, and we also assess the performance of the methods through the five models. We implement our approaches in the WebPower R package and also in Web apps to ease their application.

6.
Arch Suicide Res ; : 1-14, 2024 Feb 05.
Article En | MEDLINE | ID: mdl-38314767

OBJECTIVE: Although non-suicidal self-injury (i.e., NSSI) has been suggested as a robust risk factor of suicide, NSSI related information that is most related to suicide risk remains unclear. Commonly studied NSSI characteristics are its frequency and the number of methods endorsed. However, it may not be merely how frequent or how many different methods that matters, but "why," which alludes to the importance of NSSI functions (or why individuals engage in NSSI). Thus, this study examined how the interactions between NSSI characteristics and functions are associated with suicide risk. METHODS: Undergraduate students (n = 820) with a lifetime history of NSSI, filled out self-report measures on NSSI and suicide risk. A hierarchical regression analysis was conducted to examine the moderation effects between four 2-way interactions (i.e., method X intrapersonal; method X interpersonal; frequency X intrapersonal; frequency X interpersonal) on suicide risk. RESULTS: Main effects of all four independent variables were statistically significant. In terms of interactions, the intrapersonal function moderated both the effects of NSSI frequency and methods on suicide risk, whereas the interpersonal function moderated the effects of NSSI frequency on suicide risk. CONCLUSION: Our results highlight that some NSSI related information than others are more indicative of suicide risk. In particular, the combination of NSSI functions, along with its frequency and number of methods, holds promise when assessing for current and lifetime suicidal thoughts and behaviors.

7.
Micromachines (Basel) ; 15(1)2024 Jan 12.
Article En | MEDLINE | ID: mdl-38258249

In this paper, a microheater that can absorb thermal stress and has a large heating area is demonstrated by optimizing the structure and process of the microheater. Four symmetrically distributed elongated support beam structures were machined around the microheater via deep silicon etching. This design efficiently mitigates the deformation of the heated region caused by thermal expansion and enhances the structural stability of the microheater. The updated microheater no longer converts the work area into a thin film; instead, it creates a stable heating platform that can uniformly heat a work area measuring 10 × 10 mm2. The microheater is verified to have high temperature uniformity and structural stability in finite element simulation. Finally, thorough investigations of electrical-thermal-structural characterization were conducted. The test findings show that the new microheater can achieve 350 °C with a power consumption of 6 W and a thermal reaction time of 22 s. A scan of its whole plane reveals that the surface of the working area of the new microheater is flat and does not distort in response to variations in temperature, offering good structural stability.

8.
J Am Chem Soc ; 146(5): 2901-2906, 2024 Feb 07.
Article En | MEDLINE | ID: mdl-38271666

Macrocyclic arenes have emerged as pivotal scaffolds in supramolecular chemistry. Despite their significant contributions to molecular recognition and diverse applications, challenges persist in the development of macrocyclic arene-based crystalline materials, particularly in achieving porosity and addressing limitations in adsorption efficiency resulting from the small cavity sizes of existing macrocyclic arenes. In this study, we present the design and synthesis of a novel macrocyclic arene, clamparene (CLP), featuring a rigid backbone, easy synthesis, and a sizable cavity. CLP self-assembles into one-dimensional sub-nanotubes that further organize into a three-dimensional porous framework in the solid state. The crystalline solid of CLP exhibits potential as a porous crystalline adsorbent for various benzene-based contaminants with rapid adsorption kinetics, large uptake amounts, and good recyclability.

9.
J Am Chem Soc ; 146(2): 1410-1422, 2024 Jan 17.
Article En | MEDLINE | ID: mdl-38179949

Alkene radical ions constitute an integral and unique class of reactive intermediates for the synthesis of valuable compounds because they have both unpaired spins and charge. However, relatively few synthetic applications of alkene radical anions have emerged due to a dearth of generally applicable and mild radical anion generation approaches. Precise control over the chemo- and stereoselectivity in alkene radical anion-mediated processes represents another long-standing challenge due to their high reactivity. To overcome these issues, here, we develop a new redox-neutral strategy that seamlessly merges photoredox and copper catalysis to enable the controlled generation of alkene radical anions and their orthogonal enantioselective cyanofunctionalization via distonic-like species. This new strategy enables highly regio-, chemo-, and enantioselective hydrocyanation, deuterocyanation, and cyanocarboxylation of alkenes without stoichiometric reductants or oxidants under visible light irradiation. This protocol provides a new blueprint for the exploration of the transformation potential of alkene radical anions.

10.
Int Immunopharmacol ; 127: 111232, 2024 Jan 25.
Article En | MEDLINE | ID: mdl-38091830

To retrospectively analyze the efficacy and safety of venetoclax combined with azacitidine (VEN + AZA) in the treatment of elderly patients with acute myeloid leukemia. The clinical data for 57 AML patients treated with the VEN + AZA regimen from December 2019 to November 2022 in the Department of Hematology, General Hospital of Tianjin Medical University, were collected. Of the 57 patients included in this study, the mean age of onset was 69.89 (±8.88) years. The median follow-up time was 8.57 months, and the median OS time was 11.50 months. The ORR, CR rate, and MRD (<0.1%) negativity rate were 87.5%, 68.8%, and 58.3%, respectively. The median OS was longer in patients who achieved CR/CRi and who were MRD-negative than in those who did not. MRD negativity was less likely to be achieved in patients aged ≥75 years and with ECOG scores of ≥3. Compared to traditional intensive chemotherapy, MRD negative was achieved more quickly with VEN + AZA regimens in patients with newly diagnosed AML. Advanced age and ECOG score were risk factors for negative MRD. The dominant adverse reactions were hematological adverse events. VEN + AZA regimens in elderly unfit patients with previously untreated newly diagnosed AML have sufficient efficacy and safety.


Azacitidine , Leukemia, Myeloid, Acute , Sulfonamides , Aged , Humans , Middle Aged , Azacitidine/therapeutic use , Retrospective Studies , Bridged Bicyclo Compounds, Heterocyclic/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use
11.
Inorg Chem ; 62(42): 17236-17240, 2023 Oct 23.
Article En | MEDLINE | ID: mdl-37816176

Considerable progress in the construction of efficient fluorescence-resonance energy transfer (FRET) systems has promoted the development of artificial energy transfer materials. However, despite recent advances, the exploration of efficient and easy strategies to fabricate novel supramolecular systems with FRET activities is still a challenge. Here, we report that a two-step FRET system was successfully achieved, driven by platinum metallacycle based host-guest interactions. The two-step FRET system is used for the preparation of a white-light-emitting diode and serves as a nanoreactor for the photosynthetic process. This work offers a strategy for the fabrication of FRET systems and opens opportunities for functional materials constructed by platinum(II) metallacycle based host-guest interactions.

12.
J Comput Biol ; 30(9): 972-984, 2023 09.
Article En | MEDLINE | ID: mdl-37682321

Genetic mutations can impact protein-protein interactions (PPIs) in biomedical literature. Automated extraction of PPIs affected by gene mutations from biomedical literature can aid in evaluating the clinical importance of gene variations, which is crucial for the advancement of precision medicine. In this study, a new model called the Gaussian-enhanced representation model (GRM) is introduced for PPI extraction. The model utilizes the Gaussian probability distribution to produce a target entity representation based on the BioBERT pretraining model. The GRM assigns more weight to target protein entities and their adjacent entities, resolving the problem of lengthy input text and scattered distribution of target entities in the PPI extraction task. Additionally, the model introduces a supervised contrast learning approach to enhance its effectiveness and robustness. Experiments on the BioCreative VI data set demonstrate that our proposed GRM model has achieved state-of-the-art performance.


Clinical Relevance , Learning , Mutation , Normal Distribution , Precision Medicine
13.
Food Chem Toxicol ; 181: 114059, 2023 Nov.
Article En | MEDLINE | ID: mdl-37758048

To evaluate and compare the safety of four selenium supplements, namely Se-enriched peptides (SeP), yeast selenium (SeY), L-Se-methylselenocysteine (L-SeMc) and sodium selenite (Na2SeO3), the subchronic toxicity study was designed by 90-day gavage administration in Sprague-Dawley rats. The doses of SeP, SeY, L-SeMc and Na2SeO3 were 0.15, 0.30 and 0.60 mg/kg bw/day, with additional dose of 0.45 mg/kg L-SeMc (All dose calculated as Se). Symptoms like growling, hair loss and significant weight loss were found at 0.60 mg/kg of L-SeMc, but not in other groups. At the dose of 0.60 mg/kg, females in Na2SeO3, SeY and L-SeMc groups showed significant elevations in ALT and/or ALP. Pathologic manifestations such as bile duct hyperplasia and cholestasis were predominantly found in females at 0.6 mg/kg of L-SeMc and SeY groups, and in males at same dose of L-SeMc group showed marked testicular atrophy. 0.60 mg/kg of SeY and Na2SeO3, and 0.30, 0.45, 0.60 mg/kg of L-SeMc induced significant reductions in sperm motility rates, rapid movement and amount. In conclusion, the NOAEL of SeP, SeY, L-SeMc, Na2SeO3 was all 0.30 mg/kg for female, and 0.60, 0.30, 0.15 and 0.30 mg/kg for male respectively. Liver and reproductive organs are possible toxic target organs of hyper selenium.


Selenium , Male , Female , Rats , Animals , Rats, Sprague-Dawley , Selenium/toxicity , Sperm Motility , Dietary Supplements/toxicity , Sodium Selenite/toxicity , Saccharomyces cerevisiae
14.
Micromachines (Basel) ; 14(9)2023 Sep 21.
Article En | MEDLINE | ID: mdl-37763968

This study presents a newly developed piezoelectric drive mechanism for the purpose of designing, analyzing, and testing a micro-positioning platform driven by piezoelectric actuators. The platform incorporates a piezoelectric ceramic actuator and a flexible hinge drive and features a symmetrical two-stage lever (STSL) amplification mechanism and a parallelogram output structure. The implementation of this design has led to notable enhancements in the dynamic properties of the platform, thereby eliminating the undesired parasitic displacement of the mechanism. An analytical model describing the fully elastic deformation of the platform is established, which is further verified by finite element simulation. Finally, the static and dynamic performances of the platform are comprehensively evaluated through experiments. A closed-loop control strategy is adopted to eliminate the nonlinear hysteresis phenomenon of the piezoceramic actuator (PEA). The experimental results show that the piezoelectric micro-actuator platform has a motion range of 97.84 µm × 98.03 µm; the output coupling displacement error is less than 1%; the resolutions of the two axes are 8.1 nm and 8 nm, respectively; and the x-axis and y-axis trajectory tracking errors are both 0.6%. The piezoelectric micromotion platform has good dynamic properties, precision, and stability. The design has a wide application potential in the field of micro-positioning.

15.
World J Gastroenterol ; 29(26): 4200-4213, 2023 Jul 14.
Article En | MEDLINE | ID: mdl-37475847

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract. Tyrosine kinase inhibitors, such as imatinib, have been used as first-line therapy for the treatment of GISTs. Although these drugs have achieved considerable efficacy in some patients, reports of resistance and recurrence have emerged. Extracellular signal-regulated kinase 1/2 (ERK1/2) protein, as a member of the mitogen-activated protein kinase (MAPK) family, is a core molecule of this signaling pathway. Nowadays, research reports on the important clinical and prognostic value of phosphorylated-ERK (P-ERK) and phosphorylated-MAPK/ERK kinase (P-MEK) proteins closely related to raf kinase inhibitor protein (RKIP) have gradually emerged in digestive tract tumors such as gastric cancer, colon cancer, and pancreatic cancer. However, literature on the expression of these downstream proteins combined with RKIP in GIST is scarce. This study will focus on this aspect and search for answers to the problem. AIM: To detect the expression of RKIP, P-ERK, and P-MEK protein in GIST and to analyze their relationship with clinicopathological characteristics and prognosis of this disease. Try to establish a new prognosis evaluation model using RKIP and P-ERK in combination with analysis and its prognosis evaluation efficacy. METHODS: The research object of our experiment was 66 pathologically diagnosed GIST patients with complete clinical and follow-up information. These patients received surgical treatment at China Medical University Affiliated Hospital from January 2015 to January 2020. Immunohistochemical method was used to detect the expression of RKIP, P-ERK, and P-MEK proteins in GIST tissue samples from these patients. Kaplan-Meier method was used to calculate the survival rate of 63 patients with complete follow-up data. A Nomogram was used to represent the new prognostic evaluation model. The Cox multivariate regression analysis was conducted separately for each set of risk evaluation factors, based on two risk classification systems [the new risk grade model vs the modified National Institutes of Health (NIH) 2008 risk classification system]. Receiver operating characteristic (ROC) curves were used for evaluating the accuracy and efficiency of the two prognostic evaluation systems. RESULTS: In GIST tissues, RKIP protein showed positive expression in the cytoplasm and cell membrane, appearing as brownish-yellow or brown granules. The expression of RKIP was related to GIST tumor size, NIH grade, and mucosal invasion. P-ERK protein exhibited heterogeneous distribution in GIST cells, mainly in the cytoplasm, with occasional presence in the nucleus, and appeared as brownish-yellow granules, and the expression of P-ERK protein was associated with GIST tumor size, mitotic count, mucosal invasion, and NIH grade. Meanwhile, RKIP protein expression was negatively correlated with P-ERK expression. The results in COX multivariate regression analysis showed that RKIP protein expression was not an independent risk factor for tumor prognosis. However, RKIP combined with P-ERK protein expression were identified as independent risk factors for prognosis with statistical significance. Furthermore, we establish a new prognosis evaluation model using RKIP and P-ERK in combination and obtained the nomogram of the new prognosis evaluation model. ROC curve analysis also showed that the new evaluation model had better prognostic performance than the modified NIH 2008 risk classification system. CONCLUSION: Our experimental results showed that the expression of RKIP and P-ERK proteins in GIST was associated with tumor size, NIH 2008 staging, and tumor invasion, and P-ERK expression was also related to mitotic count. The expression of the two proteins had a certain negative correlation. The combined expression of RKIP and P-ERK proteins can serve as an independent risk factor for predicting the prognosis of GIST patients. The new risk assessment model incorporating RKIP and P-ERK has superior evaluation efficacy and is worth further practical application to validate.


Gastrointestinal Stromal Tumors , Humans , Extracellular Signal-Regulated MAP Kinases/metabolism , Gastrointestinal Stromal Tumors/pathology , Mitogen-Activated Protein Kinase Kinases/metabolism , Phosphatidylethanolamine Binding Protein/metabolism , Prognosis
16.
BMC Cancer ; 23(1): 694, 2023 Jul 24.
Article En | MEDLINE | ID: mdl-37488507

BACKGROUND: The Pegylated recombinant human granulocyte colony stimulating factor (PEG-rhG-CSF) has longer half-life and is given once only, which is more comfortable for patients. We aimed to evaluate the efficacy of mecapegfilgrastim for hematopoietic stem cell (HSC) mobilization in patients with hematologic malignancies and to explore the potential factors related to HSC mobilization. METHODS: A retrospective analysis was performed on patients who underwent HSC mobilization in the hematology department of Mianyang Central Hospital from April 2016 to November 2022. The number of CD34 + cells collected was compared between the patients receiving mecapegfilgrastim (PEG group) and those receiving recombinant human granulocyte colony-stimulating factor (rhG-CSF group), and the possible factors for mobilization failure were analyzed. RESULTS: The success rates of collecting CD34 + cells in the PEG group and rhG-CSF group were 80.6% and 67.7%, respectively (χ = 1.444, P = 0.229). The median CD34 + cell counts were 3.62 × 10^6/kg and 2.92 × 10^6/kg (P = 0.178), respectively. After combination with plerixafor for mobilization, the median number of CD34 + cells collected in the PEG group and rhG-CSF group were 3.64 × 10^6/kg and 3.92 × 10^6/kg, respectively, with no significant difference (P = 0.754). There was no significant difference in hematopoietic cell recovery or infection between the groups (P > 0.05). Multivariate analysis showed that more than 5 cycles of chemotherapy (OR = 15.897, 95% CI: 1.766-143.127, P = 0.014), a precollection WBC count < 32 × 10^9/L (OR = 14.441, 95% CI: 2.180-95.657, P = 0.006) and a precollection to premobilization lymphocyte ratio < 1.7 (OR = 11.388, 95% CI: 2.129-60.915, P = 0.004) were independent risk factors for HSC mobilization failure. CONCLUSIONS: The HSC mobilization efficacy of mecapegfilgrastim in patients with hematologic malignancies was comparable to that of rhG-CSF, and combination with plerixafor for mobilization was feasible and effective. Patients with more than 5 cycles of chemotherapy before HSC mobilization, a precollection WBC count lower than 32 × 10^9/L, and a precollection lymphocyte count less than 1.7 times the premobilization lymphocyte count have a high probability of HSC mobilization failure.


Hematologic Neoplasms , Heterocyclic Compounds , Peripheral Blood Stem Cells , Humans , Hematopoietic Stem Cell Mobilization , Retrospective Studies , Granulocyte Colony-Stimulating Factor , Polyethylene Glycols , Leukocyte Count
17.
Biomaterials ; 301: 122231, 2023 10.
Article En | MEDLINE | ID: mdl-37418854

The challenge of wound infections post-surgery and open trauma caused by multidrug-resistant bacteria poses a constant threat to clinical treatment. As a promising antimicrobial treatment, photothermal therapy can effectively resolve the problem of drug resistance in conventional antibiotic antimicrobial therapy. Here, we report a deep-penetration functionalized cuttlefish ink nanoparticle (CINP) for photothermal and immunological therapy of wound infections. CINP is decorated with zwitterionic polymer (ZP, namely sulfobetaine methacrylate-methacrylate copolymer) to form CINP@ZP nanoparticles. Natural CINP is found to not only exhibit photothermal destruction of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli), but also trigger macrophages-related innate immunity and enhance their antibacterial functions. The ZP coating on the surface of CINP enables nanoparticles to penetrate into deeply infected wound environment. In addition, CINP@ZP is further integrated into the thermosensitive Pluronic F127 gel (CINP@ZP-F127). After in situ spraying gel, CINP@ZP-F127 is also documented notable antibacterial effects in mice wound models infected with MRSA and E. coli. Collectively, this approach combining of photothermal therapy with immunotherapy can promote delivery efficiency of nanoparticles to the deep foci of infective wounds, and effectively eliminate wound infections.


Methicillin-Resistant Staphylococcus aureus , Nanoparticles , Wound Infection , Mice , Animals , Photothermal Therapy , Escherichia coli , Ink , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Polymers/pharmacology , Wound Infection/drug therapy , Decapodiformes
18.
Angew Chem Int Ed Engl ; 62(31): e202305767, 2023 Aug 01.
Article En | MEDLINE | ID: mdl-37280162

Macrocyclic molecule-based host-guest systems, which provide contributions for the design and construction of functional supramolecular structures, have gained increasing attention in recent years. In particular, platinum(II) metallacycle-based host-guest systems provide opportunities for chemical scientists to prepare novel materials with various functions and structures due to the well-defined shapes and cavity sizes of platinum(II) metallacycles. However, the research on platinum(II) metallacycle-based host-guest systems has been given little attention. In this article, we demonstrate the host-guest complexation between a platinum(II) metallacycle and a polycyclic aromatic hydrocarbon molecule, naphthalene. Taking advantage of metallacycle-based host-guest interactions and the dynamic property of reversible Pt coordination bonds, a [2]rotaxane is efficiently prepared by employing a template-directed clipping procedure. The [2]rotaxane is further applied to the fabrication of an efficient light-harvesting system with multi-step energy transfer process. This work comprises an important supplement to macrocycle-based host-guest systems and demonstrates a strategy for efficient production of well-defined mechanically interlocked molecules with practical values.

19.
Org Biomol Chem ; 21(19): 4022-4027, 2023 05 17.
Article En | MEDLINE | ID: mdl-37128802

Amino acids play an important role in the formation of proteins, enzymes, hormones and peptides in animals. Moreover, aspartic acid and glutamic acid have a critical impact on the central nervous system as excitatory neurotransmitters. Here, we report the highly selective detection of L-glutamic acid (L-Glu) and L-aspartic acid (L-Asp) using fluorescent microparticles constructed by the combination of aggregation-induced emission and self-assembly-induced Förster resonance energy transfer.


Aspartic Acid , Glutamic Acid , Animals , Aspartic Acid/chemistry , Fluorescence Resonance Energy Transfer , Amino Acids , Peptides , Coloring Agents
20.
J Am Chem Soc ; 145(22): 12233-12243, 2023 Jun 07.
Article En | MEDLINE | ID: mdl-37222742

Photocatalytic [3 + 2] cycloadditions and control of stereochemistry have remained a substantial challenge, particularly in the context of heterocycle synthesis; sporadic successful examples have involved enantioselective [3 + 2] photocycloaddition between redox-active direct group-containing cyclopropanes and alkenes for creation of cyclopentanes. Herein, we report a cooperative catalytic system comprising a chiral nickel Lewis acid catalyst and an organic photocatalyst fueled by visible-light irradiation that allows for the hitherto elusive asymmetric [3 + 2] photocycloaddition of ß-keto esters with vinyl azides under redox-neutral conditions. This protocol enables highly enantioselective construction of polycyclic densely substituted 3,4-dihydro-2H-pyrrole heterocycles featuring two contiguous tetrasubstituted carbon stereocenters, including a useful chiral N,O-ketal motif that is not easily accessible with other catalytic methods. Mechanistic studies revealed that the overall reactivity relies on the seamless integration of dual roles of nickel catalysts by the catalytic formation of the substrate/Ni complex, assisting both photoredox event and enantioselective radical addition.

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