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Joelho , Humanos , Feminino , Adulto Jovem , Biópsia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/diagnósticoRESUMO
Hemangioma of infancy is the most common vascular tumor during infancy and childhood. Despite the proven efficacy of propranolol treatment, certain patients still encounter resistance or face recurrence. The need for frequent daily medication also poses challenges to patient adherence. Bleomycin (BLM) has demonstrated effectiveness against vascular anomalies, yet its use is limited by dose-related complications. Addressing this, this study proposes a novel approach for treating hemangiomas using BLM-loaded hyaluronic acid (HA)-based microneedle (MN) patches. BLM is encapsulated during the synthesis of polylactic acid (PLA) microspheres (MPs). The successful preparation of PLA MPs and MN patches is confirmed through scanning electron microscopy (SEM) images. The HA microneedles dissolve rapidly upon skin insertion, releasing BLM@PLA MPs. These MPs gradually degrade within 28 days, providing a sustained release of BLM. Comprehensive safety assessments, including cell viability, hemolysis ratio, and intradermal reactions in rabbits, validate the safety of MN patches. The BLM@PLA-MNs exhibit an effective inhibitory efficiency against hemangioma formation in a murine hemangioma model. Of significant importance, RNA-seq analysis reveals that BLM@PLA-MNs exert their inhibitory effect on hemangiomas by regulating the P53 pathway. In summary, BLM@PLA-MNs emerge as a promising clinical candidate for the effective treatment of hemangiomas.
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Bleomicina , Preparações de Ação Retardada , Sistemas de Liberação de Medicamentos , Hemangioma , Ácido Hialurônico , Agulhas , Poliésteres , Bleomicina/farmacologia , Animais , Camundongos , Coelhos , Hemangioma/tratamento farmacológico , Ácido Hialurônico/química , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos/métodos , Poliésteres/química , Humanos , Microesferas , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacocinética , Liberação Controlada de FármacosRESUMO
Wound infections, especially those caused by pathogenic bacteria, present a considerable public health concern due to associated complications and poor therapeutic outcomes. Herein, we developed antibacterial nanoparticles, namely, PGTP, by coordinating guanidine derivatives with a porphyrin-based sonosensitizer. The synthesized PGTP nanoparticles, characterized by their strong positive charge, effectively disrupted the bacterial biosynthesis process through charge interference, demonstrating efficacy against both Gram-negative and Gram-positive bacteria. Additionally, PGTP nanoparticles generated reactive oxygen species under ultrasound stimulation, resulting in the disruption of biofilm integrity and efficient elimination of pathogens. RNA-seq analysis unveiled the detailed mechanism of wound healing, revealing that PGTP nanoparticles, when coupled with ultrasound, impair bacterial metabolism by interfering with the synthesis and transcription of amino acids. This study presents a novel approach to combatting wound infections through ultrasound-driven charge-interfering therapy, facilitated by advanced antibacterial nanomaterials.
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Antibacterianos , Biofilmes , Nanopartículas , Infecção dos Ferimentos , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/uso terapêutico , Infecção dos Ferimentos/tratamento farmacológico , Infecção dos Ferimentos/microbiologia , Nanopartículas/química , Nanopartículas/uso terapêutico , Biofilmes/efeitos dos fármacos , Animais , Camundongos , Ondas Ultrassônicas , Espécies Reativas de Oxigênio/metabolismo , Cicatrização/efeitos dos fármacos , Humanos , Porfirinas/química , Porfirinas/farmacologia , Porfirinas/uso terapêutico , Terapia por Ultrassom/métodos , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacosRESUMO
The most common mechanical complications of acute myocardial infarction include free-wall rupture, ventricular septal rupture (VSR), papillary muscle rupture and pseudoaneurysm. It is rare for a patient to experience more than one mechanical complication simultaneously. Here, we present a case of ST-segment elevation myocardial infarction (STEMI) complicated with three mechanical complications, including ventricular apical wall rupture, ventricular aneurysm formation and ventricular septal dissection (VSD) with VSR. Cardiac auscultation revealed rhythmic S1 and S2 with a grade 3 holosystolic murmur at the left sternal border. Electrocardiogram indicated anterior ventricular STEMI. Serological tests showed a significant elevated troponin I. Bedside echocardiography revealed ventricular apical wall rupture, apical left ventricle aneurysm and VSD with VSR near the apex. This case demonstrates that several rare mechanical complications can occur simultaneously secondary to STEMI and highlights the importance of bedside echocardiography in the early diagnosis of mechanical complications.
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Aneurisma Cardíaco , Ruptura Cardíaca Pós-Infarto , Infarto do Miocárdio com Supradesnível do Segmento ST , Ruptura do Septo Ventricular , Idoso , Humanos , Eletrocardiografia , Aneurisma Cardíaco/diagnóstico por imagem , Aneurisma Cardíaco/etiologia , Aneurisma Cardíaco/complicações , Aneurisma Cardíaco/fisiopatologia , Ruptura Cardíaca Pós-Infarto/etiologia , Ruptura Cardíaca Pós-Infarto/diagnóstico por imagem , Ruptura Cardíaca Pós-Infarto/diagnóstico , Testes Imediatos , Valor Preditivo dos Testes , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/complicações , Infarto do Miocárdio com Supradesnível do Segmento ST/terapia , Infarto do Miocárdio com Supradesnível do Segmento ST/fisiopatologia , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Resultado do Tratamento , Ruptura do Septo Ventricular/etiologia , Ruptura do Septo Ventricular/diagnóstico por imagem , Ruptura do Septo Ventricular/fisiopatologia , Ruptura do Septo Ventricular/diagnóstico , Ruptura do Septo Ventricular/cirurgia , FemininoRESUMO
Peptide-based supramolecules exhibit great potential in various fields due to their improved target recognition ability and versatile functions. However, they still suffer from numerous challenges for the biopharmaceutical analysis, including poor self-assembly ability, undesirable ligand-antibody binding rates, and formidable target binding barriers caused by ligand crowding. To tackle these issues, a "polyvalent recognition" strategy employing the CD20 mimotope peptide derivative NBD-FFVLR-GS-WPRWLEN (acting on the CDR domains of rituximab) was proposed to develop supramolecular nanofibers for target antibody recognition. These nanofibers exhibited rapid self-assembly within only 1 min and robust stability. Their binding affinity (179 nM) for rituximab surpassed that of the monomeric peptide (7 µM) by over 38-fold, highlighting that high ligand density and potential polyvalent recognition can efficiently overcome the target binding barriers of traditional supramolecules. Moreover, these nanofibers exhibited an amazing "instantaneous capture" rate (within 15 s), a high recovery (93 ± 3%), and good specificity for the target antibody. High-efficiency enrichment of rituximab was achieved from cell culture medium with good recovery and reproducibility. Intriguingly, these peptide nanofibers combined with bottom-up proteomics were successful in tracking the deamidation of asparagine 55 (from 10 to 16%) on the rituximab heavy chain after 21 day incubation in human serum. In summary, this study may open up an avenue for the development of versatile mimotope peptide supramolecules for biorecognition and bioanalysis of biopharmaceuticals.
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Produtos Biológicos , Nanofibras , Humanos , Rituximab , Nanofibras/química , Ligantes , Reprodutibilidade dos Testes , Peptídeos/químicaRESUMO
Due to low immobilized ligand density, limited binding capacity, and severe interference from serum proteins, developing ideal peptide-based biomaterials for precise recognition and in vivo analysis of biopharmaceuticals remains a huge challenge. In this study, mimotope peptide modified pompon mum-like biomimetic magnetic microparticles (MMPs, 3.8 µm) that mimic the specific functionalities of CD20 on malignant B cells were developed for the first time. Benefit from the numerous ligand binding sites (Ni2+) on the pompon mum-like MMPs, these novel materials achieved ≥10 times higher peptide ligand densities (>2300 mg/g) and antibody binding capacities (1380 mg/g) compared to previous reported biomaterials. Leveraging the high specificity of the mimotope peptide, rituximab can be precisely recognized and enriched from cell culture media or serum samples. We also established an LCâMS/MS method using the MMPs for tracking rituximab biotransformation in patient serum. Intriguingly, deamidation of Asn55 and Asn33, as well as oxidation of Met81 and Met34 were observed at the key complementarity determining regions of rituximab, which could potentially influence antibody function and require careful monitoring. Overall, these versatile biomimetic MMPs demonstrate superior recognition and enrichment capabilities for target antibodies, offering interesting possibilities for biotransformation analysis of biopharmaceuticals in patient serum.
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BACKGROUND: Centromeres are critical for maintaining genomic stability in eukaryotes, and their turnover shapes genome architectures and drives karyotype evolution. However, the co-evolution of centromeres from different species in allopolyploids over millions of years remains largely unknown. RESULTS: Here, we generate three near-complete genome assemblies, a tetraploid Brachypodium hybridum and its two diploid ancestors, Brachypodium distachyon and Brachypodium stacei. We detect high degrees of sequence, structural, and epigenetic variations of centromeres at base-pair resolution between closely related Brachypodium genomes, indicating the appearance and accumulation of species-specific centromere repeats from a common origin during evolution. We also find that centromere homogenization is accompanied by local satellite repeats bursting and retrotransposon purging, and the frequency of retrotransposon invasions drives the degree of interspecies centromere diversification. We further investigate the dynamics of centromeres during alloploidization process, and find that dramatic genetics and epigenetics architecture variations are associated with the turnover of centromeres between homologous chromosomal pairs from diploid to tetraploid. Additionally, our pangenomes analysis reveals the ongoing variations of satellite repeats and stable evolutionary homeostasis within centromeres among individuals of each Brachypodium genome with different polyploidy levels. CONCLUSIONS: Our results provide unprecedented information on the genomic, epigenomic, and functional diversity of highly repetitive DNA between closely related species and their allopolyploid genomes at both coarse and fine scale.
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Brachypodium , Diploide , Humanos , Tetraploidia , Brachypodium/genética , Retroelementos , Centrômero/genéticaRESUMO
Diabetic kidney disease (DKD) stands as the predominant cause of chronic kidney disease (CKD) on a global scale, with its incidence witnessing a consistent annual rise, thereby imposing a substantial burden on public health. The pathogenesis of DKD is primarily rooted in metabolic disorders and inflammation. Recent years have seen a surge in studies highlighting the regulatory impact of energy metabolism on innate immunity, forging a significant area of research interest. Within this context, fibroblast growth factor 21 (FGF21), recognized as an energy metabolism regulator, assumes a pivotal role. Beyond its role in maintaining glucose and lipid metabolism homeostasis, FGF21 exerts regulatory influence on innate immunity, concurrently inhibiting inflammation and fibrosis. Serving as a nexus between energy metabolism and innate immunity, FGF21 has evolved into a therapeutic target for diabetes, nonalcoholic steatohepatitis, and cardiovascular diseases. While the relationship between FGF21 and DKD has garnered increased attention in recent studies, a comprehensive exploration of this association has yet to be systematically addressed. This paper seeks to fill this gap by summarizing the mechanisms through which FGF21 operates in DKD, encompassing facets of energy metabolism and innate immunity. Additionally, we aim to assess the diagnostic and prognostic value of FGF21 in DKD and explore its potential role as a treatment modality for the condition.
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Diabetes Mellitus , Nefropatias Diabéticas , Fatores de Crescimento de Fibroblastos , Humanos , Inflamação/metabolismo , Imunidade Inata , Metabolismo EnergéticoRESUMO
An increasing body of evidence suggests that the state of hyperalgesia could be socially transferred from one individual to another through a brief empathetic social contact. However, how the social transfer of pain develops during social contact is not well-known. Utilizing a well-established mouse model, the present study aims to study the functional role of visual and olfactory cues in the development of socially-transferred mechanical hypersensitivity. Behavioral tests demonstrated that one hour of brief social contact with a conspecific mouse injected with complete Freund's adjuvant (CFA) was both sufficient and necessary for developing socially-transferred mechanical hypersensitivity. One hour of social contact with visual deprivation could not prevent the development of socially-transferred mechanical hypersensitivity, and screen observation of a CFA cagemate was not sufficient to develop socially-transferred mechanical hypersensitivity in bystanders. Methimazole-induced olfactory deprivation, a compound with reversible toxicity on the nasal olfactory epithelium, was sufficient to prevent the development of socially-transferred mechanical hypersensitivity. Intriguingly, repeated but not acute olfactory exposure to the CFA mouse bedding induced a robust decrease in 50 % paw withdrawal thresholds (50 %PWTs) to mechanical stimuli, an effect returned to the baseline level after two days of washout with clean bedding. The findings strongly indicate that the normal olfactory function is crucial for the induction of mechanical hypersensitivity through brief empathetic contact, offering valuable insights for animal housing in future pain research.
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Hiperalgesia , Dor , Camundongos , Masculino , Animais , Camundongos Endogâmicos C57BL , Hiperalgesia/induzido quimicamente , Modelos Animais de Doenças , InflamaçãoRESUMO
Activating cGAS-STING pathway has great potential to achieve effective antitumor immunotherapy. However, mutant p53 (mutp53), a commonly observed genetic alteration in over 50% of human cancer, will impede the therapeutic performance of the cGAS-STING pathway. Herein, multifunctional ZIF-8@MnO2 nanoparticles are constructed to degrade mutp53 and facilitate the cGAS-STING pathway. The synthesized ZIF-8@MnO2 can release Zn2+ and Mn2+ in cancer cells to induce oxidative stress and cytoplasmic leakage of fragmented mitochondrial double-stranded DNAs (dsDNAs). Importantly, the released Zn2+ induces variable degradation of multifarious p53 mutants through proteasome ubiquitination, which can alleviate the inhibitory effects of mutp53 on the cGAS-STING pathway. In addition, the released Mn2+ further increases the sensitivity of cGAS to dsDNAs as immunostimulatory signals. Both in vitro and in vivo results demonstrate that ZIF-8@MnO2 effectively promotes the cGAS-STING pathway and synergizes with PD-L1 checkpoint blockades, leading to remarkable regression of local tumors as well as distant metastases of breast cancer. This study proposes an inorganic metal ion-based nanoplatform to enhance the cGAS-STING-mediated antitumor immunotherapy, especially to those tumors with mutp53 expression.
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Estruturas Metalorgânicas , Neoplasias , Humanos , Proteína Supressora de Tumor p53 , Compostos de Manganês , Óxidos , ImunoterapiaRESUMO
BACKGROUND: Acquired immune deficiency syndrome (AIDS) associated with eosinophilic gastroenteritis is rare. We report a case of duodenal "stone" inducing acute pancreatitis with eosinophilic gastroduodenitis in an AIDS patient. CASE SUMMARY: A 73-year-old female AIDS patient came to the hospital with recurrent abdominal pain for 20 days. Computed tomography (CT) showed pancreatitis with exudation and a high-density shadow under the gastric antrum. Gastroscopy showed that the descending part of the duodenum was blocked by a "stone". The mucosa of the duodenum was rough, and a red polyp was found on the gastric body. The pathology result was chronic inflammation with eosinophilic granulocytes in the duodenal mucosa and gastric body polyp. CONCLUSION: When AIDS patients suffer acute pancreatitis, the possibility of eosinophilic gastroenteritis needs to be considered to enable the patient to accept timely treatment.
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To in-depth explore the action mechanism of C-reactive protein (CRP) and precisely study its signaling pathways, it is essential to acquire high-purity CRP while preserving its intact structure and functionality. In this study, we propose and fabricate a high-density 2-methacryloyloxyethyl phosphorylcholine (MPC)-modified membrane roll column (MPC-MRC) using a surface-initiated atom transfer radical polymerization (SI-ATRP) approach, which can overcome these limitations (long incubation time and low adsorption capacity) of conventional enrichment materials. The MPC-MRC incorporates a high-density 2-hydroxyethyl methacrylate polymer brush to prevent non-specific protein adsorption and multiple MPC polymer brush layers for high-performance enrichment of CRP in the company of calcium ions. Furthermore, the MPC-MRC exhibits high permeability, hydrophilicity, and mechanical strength. Compared to previous technologies, this novel material demonstrates significantly higher CRP binding capacity (310.3 mg/g), shorter processing time (only 15 min), and lower cost (only 12 USD/column). Notably, the MPC-MRC enables fast and effective purification of CRP from both human and rat serum, exhibiting good selectivity, recovery (> 91.3 %), and purity (> 95.2 %). Thus, this proposed purification approach based on MPC-MRC holds great potential for target protein enrichment from complex samples, as well as facilitating in-depth studies of its biological functions.
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Biomimética , Proteína C-Reativa , Animais , Humanos , Ratos , Proteína C-Reativa/química , Metacrilatos/química , Polímeros/química , Fosforilcolina/química , Propriedades de Superfície , AdsorçãoRESUMO
By extending the photoinduced oxidative mechanism of aryl tertiary amines proposed earlier to an alkaline environment based on the prediction of quantum mechanics computations and the validation of meticulous experiments, we discovered a photoinduced oxidative N-dealkylation method for both aryl tertiary amines and amides. The dealkylation was achieved in an alkaline environment under mild conditions accompanied by excellent functional group tolerance.
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Dual-energy computed tomography (DECT) is a commonly used imaging technique for detecting and diagnosing liver cancer. Currently, it is performed using clinically approved iodinated small molecule contrast agents (CAs). However, these iodinated CAs have several drawbacks, including sub-optimal contrast generation and contra-indication in patients with renal insufficiency. Herein, we synthesized tungsten-based CAs (i.e., WO3-x NPs) with excellent biocompatibility and investigated their effectiveness in DECT imaging. WO3-x NPs significantly enhanced the contrast between liver tumors and normal liver tissues as indicated by in vivo DECT imaging. Furthermore, WO3-x NPs exhibited excellent biocompatibility and minimal systemic toxicity. This study introduces a novel class of CAs for DECT and presents a promising method for accurate early diagnosis of liver tumors.
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Neoplasias Hepáticas , Nanopartículas , Humanos , Meios de Contraste , Tungstênio , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X/métodos , Neoplasias Hepáticas/diagnóstico por imagemRESUMO
Diabetic kidney disease (DKD) is a prevalent complication of diabetes, often leading to end-stage renal disease. Animal models have been widely used to study the pathogenesis of DKD and evaluate potential therapies. However, current animal models often fail to fully capture the pathological characteristics of renal injury observed in clinical patients with DKD. Additionally, modeling DKD is often a time-consuming, costly, and labor-intensive process. The current review aims to summarize modeling strategies in the establishment of DKD animal models by utilizing meta-analysis related methods and to aid in the optimization of these models for future research. A total of 1215 articles were retrieved with the keywords of "diabetic kidney disease" and "animal experiment" in the past 10 years. Following screening, 84 articles were selected for inclusion in the meta-analysis. Review manager 5.4.1 was employed to analyze the changes in blood glucose, glycosylated hemoglobin, total cholesterol, triglyceride, serum creatinine, blood urea nitrogen, and urinary albumin excretion rate in each model. Renal lesions shown in different models that were not suitable to be included in the meta-analysis were also extensively discussed. The above analysis suggested that combining various stimuli or introducing additional renal injuries to current models would be a promising avenue to overcome existing challenges and limitations. In conclusion, our review article provides an in-depth analysis of the limitations in current DKD animal models and proposes strategies for improving the accuracy and reliability of these models that will inspire future research efforts in the DKD research field.
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Diabetes Mellitus , Nefropatias Diabéticas , Falência Renal Crônica , Humanos , Animais , Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/tratamento farmacológico , Reprodutibilidade dos Testes , Rim , Testes de Função Renal , Falência Renal Crônica/complicaçõesRESUMO
BACKGROUND: Cutaneous erythema is one of the most common signs of arteriovenous malformations (AVMs) in the head and neck region, influencing aesthetic appearance. Surgical resection of AVMs may lead to cicatrization of the skin or aggravation of the lesion. Laser treatment, although effective in improving superficial vascular lesions, cannot prevent deep AVMs from further development. OBJECTIVE: The authors propose an absolute ethanol embolization therapy that can effectively and safely eradicate the nidus with a favorable aesthetic outcome. METHODS: The authors conducted a retrospective observational study of 14 AVM patients with distinct cutaneous erythema in the head and neck region undergoing embolotherapy in a single primary care center. Symptoms before and after treatment, complications, and degree of devascularization were recorded and assessed. Changes in cutaneous redness were evaluated using a previously reported quantitative measurement. RESULTS: Complete symptomatic relief was observed in 5 patients, and major improvement was observed in 9 patients. The mean Δ a * value of the color change had a significant reduction of 6.50 ± 4.04, p < .001, indicating a remarkable remission of cutaneous erythema. CONCLUSION: Ethanol embolization is an effective and safe treatment for head and neck AVMs with excellent aesthetic outcomes and might become a potential treatment method for other superficial vascular anomalies.
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Malformações Arteriovenosas , Embolização Terapêutica , Humanos , Etanol/uso terapêutico , Resultado do Tratamento , Malformações Arteriovenosas/cirurgia , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Eritema/etiologia , Eritema/terapia , Estudos RetrospectivosRESUMO
CONTEXT: Diabetic nephropathy (DN) is the main cause of end-stage renal disease. Modified Shen-Yan-Fang-Shuai formula (M-SYFSF) has excellent clinical efficacy in treating diabetic kidney disease. However, the potential mechanism of M-SYFSF remains unknown. OBJECTIVE: To investigate the mechanism of M-SYFSF against DN by network pharmacological analysis and biological experiments. MATERIALS AND METHODS: Utilizing a web-based pharmacology database, the potential mechanisms of M-SYFSF against DN were identified. In vivo experiments, male SD rats were injected with streptozotocin (50 mg/kg) and got uninephrectomy to construct a model of DN. M-SYFSF (11.34 g/kg/d) was gavaged once per day for 12 weeks after model establishment. In vitro experiments, human proximal tubular cells (HK-2) were performed with advanced glycation end-products (AGEs) (100 µg/mL), then intervened with M-SYFSF freeze-dried powder. Pathological staining, WB, IHC, ELISA were conducted to explore the mechanism of M-SYFSF against DN. RESULTS: Network pharmacological analysis showed that MAPK pathway was the potential pathway. Results showed that compared with the Model group, M-SYFSF significantly reduced 24h urine albumin, UACR, and serum creatinine levels (54.90 ± 26.67 vs. 111.78 ± 4.28, 8.87 ± 1.69 vs. 53.94 ± 16.01, 11.56 ± 1.70 vs. 118.70 ± 49.57, respectively), and improved renal pathological changes. Furthermore, the intervention of M-SYFSF reduced the expression of pro-inflammatory cytokines and inhibited the activation of MAPK pathway in AGEs-treated HK-2 cells. DISCUSSION AND CONCLUSION: M-SYFSF is likely to reduce inflammation in DN by inhibiting the MAPK pathway. It provides a theoretical basis for the clinical application of M-SYFSF in the treatment of DN.
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Diabetes Mellitus Experimental , Nefropatias Diabéticas , Medicamentos de Ervas Chinesas , Ratos , Masculino , Humanos , Animais , Nefropatias Diabéticas/metabolismo , Farmacologia em Rede , Ratos Sprague-Dawley , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Produtos Finais de Glicação Avançada/metabolismoRESUMO
Centromeres (CEN) are the chromosomal regions that play a crucial role in maintaining genomic stability. The underlying highly repetitive DNA sequences can evolve quickly in most eukaryotes, and promote karyotype evolution. Despite their variability, it is not fully understood how these widely variable sequences ensure the homeostasis of centromere function. In this study, we investigated the genetics and epigenetics of CEN in a population of wheat lines from global breeding programs. We captured a high degree of sequences, positioning, and epigenetic variations in the large and complex wheat CEN. We found that most CENH3-associated repeats are Cereba element of retrotransposons and exhibit phylogenetic homogenization across different wheat lines, but the less-associated repeat sequences diverge on their own way in each wheat line, implying specific mechanisms for selecting certain repeat types as functional core CEN. Furthermore, we observed that CENH3 nucleosome structures display looser wrapping of DNA termini on complex centromeric repeats, including the repositioned CEN. We also found that strict CENH3 nucleosome positioning and intrinsic DNA features play a role in determining centromere identity among different lines. Specific non-B form DNAs were substantially associated with CENH3 nucleosomes for the repositioned centromeres. These findings suggest that multiple mechanisms were involved in the adaptation of CENH3 nucleosomes that can stabilize CEN. Ultimately, we proposed a remarkable epigenetic plasticity of centromere chromatin within the diverse genomic context, and the high robustness is crucial for maintaining centromere function and genome stability in wheat 10+ lines as a result of past breeding selections.
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Histonas , Nucleossomos , Histonas/genética , Triticum/genética , Filogenia , Melhoramento Vegetal , Centrômero/genéticaRESUMO
How to illuminate dark matter has become the foremost open question in fundamental science nowadays, which is of great significance in understanding the laws of nature. Exploring exotic interactions beyond the standard model is one of the essential approaches to searching for dark matter particles. Although it has been explored in a variety of lab-scale and tabletop-scale setups over the past years, no such interactions have been observed, and improving the sensitivity significantly becomes of paramount importance, but challenging. Here, we formulate the conception of a spin-mechanical quantum chip compatible with scalable on-chip detectors. Utilizing the prototype chip realized by the integration of a mechanical resonator and a diamond with single nitrogen vacancy at the microscale, the constraints of spin-velocity-dependent interactions have been improved by two orders of magnitude, where there is no evidence for new bosons in the force range below 100 nm, i.e., in the rest-mass window of 2-10 electronvolts. Based on the proof-of-principle experiment, this promising chip can be scaled up to meet the requirements of searching for exotic interactions at preeminent sensitivity. Low-cost and high-yield chip-scale setups will accelerate the process of dark matter exploration, providing a path toward on-chip fundamental physics experiments.
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AIM: General anesthesia can induce cognitive deficits in both humans and rodents, correlating with pathological alterations in the hippocampus. However, whether general anesthesia affects olfactory behaviors remains controversial as clinical studies have produced inconsistent results. Therefore, we aimed to investigate how olfactory behaviors and neuronal activity are affected by isoflurane exposure in adult mice. METHODS: The olfactory detection test, olfactory sensitivity test, and olfactory preference/avoidance test were used to examine olfactory function. In vivo electrophysiology was performed in awake, head-fixed mice to record single-unit spiking and local field potentials in the olfactory bulb (OB). We also performed patch-clamp recordings of mitral cell activity. For morphological studies, immunofluorescence and Golgi-Cox staining were applied. RESULTS: Repeated exposure to isoflurane impaired olfactory detection in adult mice. The main olfactory epithelium, the first region exposed to anesthetics, displayed increased proliferation of basal stem cells. In the OB, a crucial hub for olfactory processing, repeated isoflurane exposure increased the odor responses of mitral/tufted cells. Furthermore, the odor-evoked high gamma response was decreased after isoflurane exposure. Whole-cell recordings further indicated that repeated isoflurane exposure increased the excitability of mitral cells, which may be due to weakened inhibitory input in isoflurane-exposed mice. In addition, elevated astrocyte activation and glutamate transporter-1 expression in the OB were observed in isoflurane-exposed mice. CONCLUSIONS: Our findings indicate that repeated isoflurane exposure impairs olfactory detection by increasing neuronal activity in the OB in adult mice.