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1.
ACS Chem Biol ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38954741

ABSTRACT

Hepatitis C virus (HCV) is a positive-stranded RNA virus that mainly causes chronic hepatitis, cirrhosis and hepatocellular carcinoma. Recently we confirmed m5C modifications within NS5A gene of HCV RNA genome. However, the roles of the m5C modification and its interaction with host proteins in regulating HCV's life cycle, remain unexplored. Here, we demonstrate that HCV infection enhances the expression of the host m5C reader YBX1 through the transcription factor MAX. YBX1 acts as an m5C reader, recognizing the m5C-modified NS5A C7525 site in the HCV RNA genome and significantly enhancing HCV RNA stability. This m5C-modification is also required for YBX1 colocalization with lipid droplets and HCV Core protein. Moreover, YBX1 facilitates HCV RNA replication, as well as viral assembly/budding. The tryptophan residue at position 65 (W65) of YBX1 is critical for these functions. Knockout of YBX1 or the application of YBX1 inhibitor SU056 suppresses HCV RNA replication and viral protein translation. To our knowledge, this is the first report demonstrating that the interaction between host m5C reader YBX1 and HCV RNA m5C methylation facilitates viral replication. Therefore, hepatic-YBX1 knockdown holds promise as a potential host-directed strategy for HCV therapy.

2.
World J Diabetes ; 15(6): 1162-1177, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38983804

ABSTRACT

Diabetic foot ulcers (DFUs) pose a critical medical challenge, significantly im-pairing the quality of life of patients. Adipose-derived stem cells (ADSCs) have been identified as a promising therapeutic approach for improving wound healing in DFUs. Despite extensive exploration of the mechanical aspects of ADSC therapy against DFU, its clinical applications remain elusive. In this review, we aimed to bridge this gap by evaluating the use and advancements of ADSCs in the clinical management of DFUs. The review begins with a discussion of the classification and clinical management of diabetic foot conditions. It then discusses the current landscape of clinical trials, focusing on their geographic distribution, reported efficacy, safety profiles, treatment timing, administration techniques, and dosing considerations. Finally, the review discusses the preclinical strategies to enhance ADSC efficacy. This review shows that many trials exhibit biases in study design, unclear inclusion criteria, and intervention protocols. In conclusion, this review underscores the potential of ADSCs in DFU treatment and emphasizes the critical need for further research and refinement of therapeutic approaches, with a focus on improving the quality of future clinical trials to enhance treatment outcomes and advance the field of diabetic wound care.

3.
J Clin Med ; 13(13)2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38999425

ABSTRACT

Background and Objectives: Pulmonary hypertension (PH) is a clinical condition with high mortality rates, particularly in patients over 65. Current guidelines recommend assessing the likelihood of pulmonary hypertension (LPH) using advanced echocardiography before proceeding to right heart catheterization. This study proposed using the common femoral vein (CFV), an accessible vein that reflects right atrial pressure, as an alternative method to assess the high likelihood of pulmonary hypertension (H-LPH). Materials and Methods: This prospective observational study included 175 emergency patients from three hospitals. Ultrasound assessed the pulsed wave Doppler (PW-Doppler) morphology of the CFV. This diagnostic yield for H-LPH was evaluated alongside traditional ultrasound parameters (right-to-left ventricular basal diameter ratio greater than 1 (RV > LV), septal flattening, right ventricular outflow acceleration time (RVOT) of less than 105 ms and/or mesosystolic notching, pulmonary artery diameter greater than the aortic root (AR) diameter or over 25 mm, early pulmonary regurgitation maximum velocity > 2.2 m/s; TAPSE/PASP less than 0.55, inferior vena cava (IVC) diameter over 21 mm with decreased inspiratory collapse, and right atrial (RA) area over 18 cm2). Results: The CFV's PW-Doppler cardiac pattern correlated strongly with H-LPH, showing a sensitivity (Sn) of 72% and a specificity (Sp) of 96%. RA dilation and TAPSE/PASP < 0.55 also played significant diagnostic roles. Conclusions: The CFV's PW-Doppler cardiac pattern is an effective indicator of H-LPH, allowing reliable exclusion of this condition when absent. This approach could simplify initial LPH evaluation in emergency settings or where echocardiographic resources are limited.

4.
Hortic Res ; 11(7): uhae136, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38994448

ABSTRACT

Flavonoids constitute the main nutraceuticals in the leaves of tea plants (Camellia sinensis). To date, although it is known that drought stress can negatively impact the biosynthesis of flavonoids in tea leaves, the mechanism behind this phenomenon is unclear. Herein, we report a protein phosphorylation mechanism that negatively regulates the biosynthesis of flavonoids in tea leaves in drought conditions. Transcriptional analysis revealed the downregulation of gene expression of flavonoid biosynthesis and the upregulation of CsMPK4a encoding a mitogen-activated protein kinase in leaves. Luciferase complementation and yeast two-hybrid assays disclosed that CsMPK4a interacted with CsWD40. Phosphorylation assay in vitro, specific protein immunity, and analysis of protein mass spectrometry indicated that Ser-216, Thr-221, and Ser-253 of CsWD40 were potential phosphorylation sites of CsMPK4a. Besides, the protein immunity analysis uncovered an increased phosphorylation level of CsWD40 in tea leaves under drought conditions. Mutation of the three phosphorylation sites generated dephosphorylated CsWD403A and phosphorylated CsWD403D variants, which were introduced into the Arabidopsis ttg1 mutant. Metabolic analysis showed that the anthocyanin and proanthocyanidin content was lower in ttg1:CsWD403D transgenic plants than ttg1::CsWD403A transgenic and wild type plants. The transient overexpression of CsWD403D downregulated the anthocyanidin biosynthesis in tea leaves. The dual-fluorescein protein complementation experiment showed that CsWD403D did not interact with CsMYB5a and CsAN2, two key transcription factors of procyanidins and anthocyanidins biosynthesis in tea plant. These findings indicate that the phosphorylation of CsWD40 by CsMPK4a downregulates the flavonoid biosynthesis in tea plants in drought stresses.

5.
Plant J ; 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38838090

ABSTRACT

Hydrolyzable tannins (HTs), a class of polyphenolic compounds found in dicotyledonous plants, are widely used in food and pharmaceutical industries because of their beneficial effects on human health. Although the biosynthesis of simple HTs has been verified at the enzymatic level, relevant genes have not yet been identified. Here, based on the parent ion-fragment ion pairs in the feature fragment data obtained using UPLC-Q-TOF-/MS/MS, galloyl phenolic compounds in the leaves of Camellia sinensis and C. oleifera were analyzed qualitatively and quantitatively. Correlation analysis between the transcript abundance of serine carboxypeptidase-like acyltransferases (SCPL-ATs) and the peak area of galloyl products in Camellia species showed that SCPL3 expression was highly correlated with HT biosynthesis. Enzymatic verification of the recombinant protein showed that CoSCPL3 from C. oleifera catalyzed the four consecutive steps involved in the conversion of digalloylglucose to pentagalloylglucose. We also identified the residues affecting the enzymatic activity of CoSCPL3 and determined that SCPL-AT catalyzes the synthesis of galloyl glycosides. The findings of this study provide a target gene for germplasm innovation of important cash crops that are rich in HTs, such as C. oleifera, strawberry, and walnut.

6.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(3): 940-944, 2024 Jun.
Article in Chinese | MEDLINE | ID: mdl-38926992

ABSTRACT

OBJECTIVE: To perform molecular diagnosis and pedigree analysis for one case with α-thalassemia who does not conform to the genetic laws, and explore the effects of a newly discovered rare mutation (HBA2:c.*12G>A) on clinical phenotypes. METHODS: Blood samples of the proband and her family members were collected for blood routine analysis, and the hemoglobin components were analyzed by capillary electrophoresis. The common α- and ß-globin gene loci in Chinese population were detected by conventional techniques (Gap-PCR, RDB-PCR). The α-globin gene sequences (HBA1, HBA2) were analyzed by Sanger sequencing. RESULTS: By analyzing the test results of proband and her family members, the genotype of the proband was -α3.7/HBA2:c.*12G>A, her father was HBA2:c.*12G>A heterozygous mutation carrier. CONCLUSION: This study identifies a rare α-globin gene mutation (HBA2:c.*12G>A) that has not been reported before. It is found that heterozygous mutation carriers present with static α-thalassemia.


Subject(s)
Hemoglobin A2 , alpha-Globins , alpha-Thalassemia , Female , Humans , Male , alpha-Globins/genetics , alpha-Thalassemia/genetics , alpha-Thalassemia/diagnosis , Genotype , Hemoglobin A2/genetics , Heterozygote , Mutation , Pedigree , Phenotype , East Asian People/genetics
7.
Cells ; 13(12)2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38920675

ABSTRACT

BACKGROUND: Ischemic post-conditioning (IPoC) has been shown to improve outcomes in limited pre-clinical models. As down-time is often unknown, this technique needs to be investigated over a range of scenarios. As this tool limits reperfusion injury, there may be limited benefit or even harm after short arrest and limited ischemia-reperfusion injury. METHODS: Eighteen male Wistar rats underwent 7 min of asphyxial arrest. Animals randomized to IPoC received a 20 s pause followed by 20 s of compressions, repeated four times, initiated 40 s into cardiopulmonary resuscitation. If return of spontaneous circulation (ROSC) was achieved, epinephrine was titrated to mean arterial pressure (MAP) of 70 mmHg. Data were analyzed using t-test or Mann-Whitney test. Significance set at p ≤ 0.05. RESULTS: The rate of ROSC was equivalent in both groups, 88%. There was no statistically significant difference in time to ROSC, epinephrine required post ROSC, carotid flow, or peak lactate at any timepoint. There was a significantly elevated MAP with IPoC, 90.7 mmHg (SD 13.9), as compared to standard CPR, 76.7 mmHg (8.5), 2 h after ROSC, p = 0.03. CONCLUSIONS: IPoC demonstrated no harm in a model of short arrest using a new arrest etiology for CPR based IPoC intervention in a rat model.


Subject(s)
Asphyxia , Disease Models, Animal , Heart Arrest , Ischemic Postconditioning , Rats, Wistar , Animals , Heart Arrest/therapy , Heart Arrest/complications , Heart Arrest/physiopathology , Male , Ischemic Postconditioning/methods , Rats , Asphyxia/complications , Cardiopulmonary Resuscitation/methods , Epinephrine
8.
bioRxiv ; 2024 May 20.
Article in English | MEDLINE | ID: mdl-38826479

ABSTRACT

Ischemia/reperfusion (I/R) injury significantly contributes to the morbidity and mortality associated with cardiac events. Poloxamer 188 (P188), a nonionic triblock copolymer, has been proposed to mitigate I/R injury by stabilizing cell membranes. However, the underlying mechanisms remain incompletely understood, particularly concerning endothelial cell function and nitric oxide (NO) production. We employed human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CMs) and endothelial cells (ECs) to elucidate the effects of P188 on cellular survival, function, and NO secretion under simulated I/R conditions. iPSC-CMs contractility and iPSC-ECs' NO production were assessed following exposure to P188. Further, an isolated heart model using Brown Norway rats subjected to I/R injury was utilized to evaluate the ex-vivo cardioprotective effects of P188, examining cardiac function and NO production, with and without the administration of a NO inhibitor. In iPSC-derived models, P188 significantly preserved CM contractile function and enhanced cell viability after hypoxia/reoxygenation. Remarkably, P188 treatment led to a pronounced increase in NO secretion in iPSC-ECs, a novel finding demonstrating endothelial protective effects beyond membrane stabilization. In the rat isolated heart model, administration of P188 during reperfusion notably improved cardiac function and reduced I/R injury markers. This cardioprotective effect was abrogated by NO inhibition, underscoring the pivotal role of NO. Additionally, a dose-dependent increase in NO production was observed in non-ischemic rat hearts treated with P188, further establishing the critical function of NO in P188 induced cardioprotection. In conclusion, our comprehensive study unveils a novel role of NO in mediating the protective effects of P188 against I/R injury. This mechanism is evident in both cellular models and intact rat hearts, highlighting the potential of P188 as a therapeutic agent against I/R injury. Our findings pave the way for further investigation into P188's therapeutic mechanisms and its potential application in clinical settings to mitigate I/R-related cardiac dysfunction.

9.
Eur J Radiol ; 177: 111571, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38925043

ABSTRACT

BACKGROUND AND OBJECTIVES: Collateral status is a pivotal determinant of clinical outcomes in acute ischemic stroke (AIS); however, its evaluation can be challenging. We investigated the predictive value of CT perfusion (CTP) derived time and density alterations versus CTP for collateral status prediction in AIS. METHODS: Consecutive patients with anterior circulation occlusion within 24 h were retrospectively included. Time-density curves of the CTP specified ischemic core, penumbra, and the corresponding contralateral unaffected brain were obtained. The collateral status was dichotomised into robust (4-5 scores) and poor (0-3 scores) using multiphase collateral scoring, as described by Menon et al.. Receiver operating characteristic curves and multivariable regression analysis were performed to assess the predictive ability of CTP-designated tissue time and density alterations, CTP for robust collaterals, and favourable outcomes (mRS score of 0-2 at 90 days). RESULTS: One-hundred patients (median age, 68 years; interquartile range, 57-80 years; 61 men) were included. A smaller ischemic core, shorter peak time delay, lower peak density decrease, lower cerebral blood volume ratio, and cerebral blood flow ratio in the CTP specified ischemic core were significantly associated with robust collaterals (PFDR ≤ 0.004). The peak time delay demonstrated the highest diagnostic value (AUC, 0.74; P < 0.001) with 66.7 % sensitivity and 73.7 % specificity. Furthermore, the peak time delay of less than 8.5 s was an independent predictor of robust collaterals and favourable clinical outcomes. CONCLUSIONS: Robust collateral status was significantly associated with the peak time delay in the ischemic core. It is a promising image marker for predicting collateral status and functional outcomes in AIS.

10.
Cell Biosci ; 14(1): 86, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38937838

ABSTRACT

BACKGROUND: Neurodevelopmental disorders (NDD), such as autism spectrum disorders (ASD) and intellectual disorders (ID), are highly debilitating childhood psychiatric conditions. Genetic factors are recognized as playing a major role in NDD, with a multitude of genes and genomic regions implicated. While the functional validation of NDD-associated genes has predominantly been carried out using mouse models, the significant differences in brain structure and gene function between mice and humans have limited the effectiveness of mouse models in exploring the underlying mechanisms of NDD. Therefore, it is important to establish alternative animal models that are more evolutionarily aligned with humans. RESULTS: In this study, we employed CRISPR/Cas9 and somatic cell nuclear transplantation technologies to successfully generate a knockout miniature pig model of the MIR137 gene, which encodes the neuropsychiatric disorder-associated microRNA miR-137. The homozygous knockout of MIR137 (MIR137-/-) effectively suppressed the expression of mature miR-137 and led to the birth of stillborn or short-lived piglets. Transcriptomic analysis revealed significant changes in genes associated with neurodevelopment and synaptic signaling in the brains of MIR137-/- miniature pig, mirroring findings from human ASD transcriptomic data. In comparison to miR-137-deficient mouse and human induced pluripotent stem cell (hiPSC)-derived neuron models, the miniature pig model exhibited more consistent changes in critical neuronal genes relevant to humans following the loss of miR-137. Furthermore, a comparative analysis identified differentially expressed genes associated with ASD and ID risk genes in both miniature pig and hiPSC-derived neurons. Notably, human-specific miR-137 targets, such as CAMK2A, known to be linked to cognitive impairments and NDD, exhibited dysregulation in MIR137-/- miniature pigs. These findings suggest that the loss of miR-137 in miniature pigs affects genes crucial for neurodevelopment, potentially contributing to the development of NDD. CONCLUSIONS: Our study highlights the impact of miR-137 loss on critical genes involved in neurodevelopment and related disorders in MIR137-/- miniature pigs. It establishes the miniature pig model as a valuable tool for investigating neurodevelopmental disorders, providing valuable insights for potential applications in human research.

11.
Phytomedicine ; 131: 155773, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38833946

ABSTRACT

BACKGROUND: The activation of the NLRP3 inflammasome has recently been revealed as a novel pathological mechanism of coronary heart disease (CHD). The Dan-Lou tablets (DLT) is widely used in the clinical treatment of CHD and prescription characterized by multi-component and multi-target regulation. However, the anti-inflammatory mechanism of DLT in the treatment of CHD remains unclear. PURPOSE: This study aimed to evaluate the effect of DLT in the treatment of CHD on the priming and activation of the NLRP3 inflammasome and to investigate the underlying anti-inflammatory mechanisms. METHODS: First, CHD rats model were established by a high-fat diet combined with left anterior coronary artery ligation (LADCA) followed by DLT intervention. The therapeutic effect of DLT was evaluated according to cardiac function, lipid level, and cardiac histopathology. Next, data-independent acquisition (DIA) proteomics was used to identify the key differential proteins of DLT intervention in CHD rats, and bioinformatics analysis was performed. Finally, the differentially expressed proteins in the NOD-like signaling pathway were verified based on bioinformatics results, and the priming and activation steps of the NLRP3 inflammasome were detected. RESULTS: In this study, a high-fat diet combined with LADCA was utilized to generate a CHD model, and DLT alleviated myocardial ischemia injury by inhibiting lipid deposition and inflammatory response. Proteomic studies observed that the RNF31, TXN2, and GBP2 of the NOD-like receptor signaling pathway were verified as the key targets of DLT in inhibiting myocardial injury in CHD rats. Furthermore, DLT in the treatment of CHD rats may function through the downregulation of P2X7R expression, thereby interfering with the priming (TLR4/MyD88/NF-κB) and activation (NLRP3/ASC/Caspase-1) of the NLRP3 inflammasome regulated by HSP90, and may then reduce the release of the IL-1ß and IL-18 inflammatory factors to play an anti-myocardial injury effect. CONCLUSION: Our findings elucidate a novel mechanism of DLT and provide some new drug evaluation targets and therapeutic strategies for CHD. This study innovatively proposed that DLT further exerts an anti-myocardial injury effect by inhibiting P2X7R expression, thereby interfering with the priming (TLR4/MyD88/NF-κB) and activation (NLRP3/ASC/Caspase-1) of the NLRP3 inflammasome regulated by HSP90, and then downregulates the release of the IL-1ß and IL-18 inflammatory factors.


Subject(s)
Coronary Disease , Drugs, Chinese Herbal , Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Rats, Sprague-Dawley , Animals , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Inflammasomes/metabolism , Male , Coronary Disease/drug therapy , Drugs, Chinese Herbal/pharmacology , Rats , Anti-Inflammatory Agents/pharmacology , Disease Models, Animal , Signal Transduction/drug effects , Diet, High-Fat/adverse effects , Tablets , Interleukin-1beta/metabolism , Inflammation/drug therapy , Myeloid Differentiation Factor 88/metabolism
12.
Medicine (Baltimore) ; 103(24): e38477, 2024 Jun 14.
Article in English | MEDLINE | ID: mdl-38875403

ABSTRACT

Preoperative laboratory data indicators significantly affect the prognosis of a variety of tumors. Nevertheless, the combined effect of systemic immune-inflammation index (SII) and prognostic nutritional index (PNI) on overall survival (OS) in patients with esophageal carcinoma remains unclear. Thus, we examined these associations among patients with postoperative staged T3N0M0 esophageal carcinoma. The data of 246 patients with postoperative staged T3N0M0 esophageal carcinoma from January 1, 2010, to December 31, 2022, were retrospectively analyzed. OS was measured from the date of pathological diagnosis until either death or the last follow-up. The Kaplan-Meier method and multivariate Cox regression model were used to analyze the relationship between neutrophil-to-lymphocyte ratio (NLR), Platelet-to-lymphocyte ratio (PLR), Platelet-to-lymphocyte ratio (LMR), SII, PNI, and OS. The predictive value of SII and PNI as a combined index was analyzed by the receiver operating characteristic curve (ROC). A total of 246 patients aged 65.5 ±â€…7.4 years were included in this study and 181 (73.6%) were male. The univariate analysis revealed that differentiation, vessel involvement, postoperative treatment, NLR, SII, PLR, LMR, PNI were predictors of OS (P < .05). After adjusted for potential confounds, multivariate Cox regression analysis showed that the differentiation, SII, PNI, and postoperative treatment were independent prognostic factors correlated with OS in patients with postoperative staged T3N0M0 esophageal carcinoma (P < .05). SII and PNI, as a combined indicator, have a higher predictive value for OS. The NLR, SII, PLR, LMR, and PNI could all be used as independent predictors of OS in patients with postoperative staged T3N0M0 esophageal carcinoma. The combination of SII and PNI can significantly improve the accuracy of prediction.


Subject(s)
Esophageal Neoplasms , Humans , Esophageal Neoplasms/surgery , Esophageal Neoplasms/mortality , Esophageal Neoplasms/blood , Esophageal Neoplasms/pathology , Male , Female , Aged , Retrospective Studies , Prognosis , Middle Aged , Neutrophils , Nutrition Assessment , Lymphocyte Count , Kaplan-Meier Estimate , Preoperative Period , Platelet Count , ROC Curve , Lymphocytes , Proportional Hazards Models , Neoplasm Staging
13.
Angew Chem Int Ed Engl ; : e202407464, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38894633

ABSTRACT

Plastic pollution is worsening the living conditions on Earth, primarily due to the toxicity and stability of non-biodegradable plastics (NBPs). Photocatalytic cracking of NBPs is emerging as a promising way to cleave inert C-C bonds and abstract the carbon atoms from these wastes into valuable chemicals and fuels. However, controlling these processes is a huge challenge, ascribed to the complicated reactions of various NBPs. Herein, we summarize recent advances in the CO2 and carbon-radical-mediated photocatalytic cracking of NBPs, with an emphasis on the pivotal intermediates. The CO2-mediated cracking proceeded with indiscriminate C-H/C-C bond cleavage of NBPs and tandem photoreduction of CO2, while carbon-radical-mediated cracking was realized by the prior activation of C-H bonds for selective C-C bond cleavage of NBPs. Catalytic generation and conversion of different intermediates greatly depend on the kinds of active species and the structure of photocatalysts under light irradiation. Meanwhile, the fate of a specific intermediate is compared with small molecule activation to reveal the key problems in the cracking of NBPs. Finally, the challenges and potential directions are discussed to improve the overall efficiency in the photocatalytic cracking of NBPs.

14.
Sensors (Basel) ; 24(11)2024 May 26.
Article in English | MEDLINE | ID: mdl-38894224

ABSTRACT

A phasemeter as a readout system for the inter-satellite laser interferometer in a space-borne gravitational wave detector requires not only high accuracy but also insensitivity to amplitude fluctuations and a large fast-acquiring range. The traditional sinusoidal characteristic phase detector (SPD) phasemeter has the advantages of a simple structure and easy realization. However, the output of an SPD is coupled to the amplitude of the input signal and has only a limited phase-detection range due to the boundedness of the sinusoidal function. This leads to the performance deterioration of amplitude noise suppression, fast-acquiring range, and loop stability. To overcome the above shortcomings, we propose a phasemeter based on a tangent phase detector (TPD). The characteristics of the SPD and TPD phasemeters are theoretically analyzed, and a fixed-point simulation is further carried out for verification. The simulation results show that the TPD phasemeter tracks the phase information well and, at the same time, suppresses the amplitude fluctuation to the noise floor of 1 µrad/Hz1/2, which meets the requirements of GW detection. In addition, the maximum lockable step frequency of the TPD phasemeter is almost three times larger than the SPD phasemeter, indicating a greater fast-acquiring range.

15.
Angew Chem Int Ed Engl ; : e202408016, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38828671

ABSTRACT

Expanding the diversity of multi-macrocyclic nanocarbons, particularly those with all-benzene scaffolds, represents intriguing yet challenging synthetic tasks. Complementary to the existing synthetic approaches, here we report an efficient and modular post-functionalization strategy that employs iridium-catalyzed C-H borylation of the highly strained meta-cycloparaphenylenes (mCPPs) and an mCPP-derived catenane. Based on the functionalized macrocyclic synthons, a number of novel all-benzene topological structures including linear and cyclic chains, polycatenane, and pretzelane have been successfully prepared and characterized, thereby showcasing the synthetic utility and potential of the post-functionalization strategy.

16.
World J Stem Cells ; 16(4): 334-352, 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38690516

ABSTRACT

Wound repair is a complex challenge for both clinical practitioners and researchers. Conventional approaches for wound repair have several limitations. Stem cell-based therapy has emerged as a novel strategy to address this issue, exhibiting significant potential for enhancing wound healing rates, improving wound quality, and promoting skin regeneration. However, the use of stem cells in skin regeneration presents several challenges. Recently, stem cells and biomaterials have been identified as crucial components of the wound-healing process. Combination therapy involving the development of biocompatible scaffolds, accompanying cells, multiple biological factors, and structures resembling the natural extracellular matrix (ECM) has gained considerable attention. Biological scaffolds encompass a range of biomaterials that serve as platforms for seeding stem cells, providing them with an environment conducive to growth, similar to that of the ECM. These scaffolds facilitate the delivery and application of stem cells for tissue regeneration and wound healing. This article provides a comprehensive review of the current developments and applications of biological scaffolds for stem cells in wound healing, emphasizing their capacity to facilitate stem cell adhesion, proliferation, differentiation, and paracrine functions. Additionally, we identify the pivotal characteristics of the scaffolds that contribute to enhanced cellular activity.

19.
Plant Biotechnol J ; 2024 May 19.
Article in English | MEDLINE | ID: mdl-38762905

ABSTRACT

Higher-order chromatin structure is critical for regulation of gene expression. In plants, light profoundly affects the morphogenesis of emerging seedlings as well as global gene expression to ensure optimal adaptation to environmental conditions. However, the changes and functional significance of chromatin organization in response to light during seedling development are not well documented. We constructed Hi-C contact maps for the cotyledon, apical hook and hypocotyl of soybean subjected to dark and light conditions. The resulting high-resolution Hi-C contact maps identified chromosome territories, A/B compartments, A/B sub-compartments, TADs (Topologically Associated Domains) and chromatin loops in each organ. We observed increased chromatin compaction under light and we found that domains that switched from B sub-compartments in darkness to A sub-compartments under light contained genes that were activated during photomorphogenesis. At the local scale, we identified a group of TADs constructed by gene clusters consisting of different numbers of Small Auxin-Upregulated RNAs (SAURs), which exhibited strict co-expression in the hook and hypocotyl in response to light stimulation. In the hypocotyl, RNA polymerase II (RNAPII) regulated the transcription of a SAURs cluster under light via TAD condensation. Our results suggest that the 3D genome is involved in the regulation of light-related gene expression in a tissue-specific manner.

20.
Org Lett ; 26(20): 4286-4291, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38722880

ABSTRACT

Represented herein is a simple thiol identified as an effective precursor to photochemically form a carbocation. Thanks to the thiyl radical rapid transformation to disulfide, which serves not only to stabilize the generated thiyl radical but also to allow the second electron transfer to form a carbocation. The resulting carbocations, including primary benzylic, secondary, and tertiary carbocations, can smoothly couple with nitrogen, oxygen, and carbon nucleophilic coupling partners as well as complex drug molecules, accompanied by elemental sulfur formation in air.

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