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1.
Rev Cardiovasc Med ; 25(8): 285, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39228484

RESUMEN

Heart failure is a prevalent and life-threatening syndrome characterized by structural and/or functional abnormalities of the heart. As a global burden with high rates of morbidity and mortality, there is growing recognition of the beneficial effects of exercise on physical fitness and cardiovascular health. A substantial body of evidence supports the notion that exercise can play a protective role in the development and progression of heart failure and improve cardiac function through various mechanisms, such as attenuating cardiac fibrosis, reducing inflammation, and regulating mitochondrial metabolism. Further investigation into the role and underlying mechanisms of exercise in heart failure may uncover novel therapeutic targets for the prevention and treatment of heart failure.

2.
ACS Appl Bio Mater ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39250682

RESUMEN

Diabetic foot ulcer (DFU) is a common and severe complication of diabetes characterized by wound neuropathy, ischemia, and susceptibility to infection, making its treatment difficult. Dressings are commonly used in treating diabetic wounds; however, they have disadvantages, including lack of flexibility and mechanical strength, lack of coagulation activity, resistance to biodegradation, and low drug delivery efficiency. Developing more effective strategies for diabetic wound treatment has become a new focus. Microneedles (MN) can be used as a drug delivery platform for DFU wounds, allowing safe, effective, painless and minimally invasive medication administration through the skin. Herein, PDA@Ag/SerMA microneedles were prepared by combining the photothermal properties of polydopamine (PDA), the antimicrobial properties of argentum (Ag), and the ability of sericin methacryloyl (SerMA) to promote cell mitosis to accelerate wound healing and treat diabetic ulcer wounds. The results revealed that PDA@Ag/SerMA microneedles exhibited approximately 100% antimicrobial efficacy against Staphylococcus aureus and Escherichia coli under 808 nm near-infrared (NIR) irradiation. Furthermore, the wound healing rate of mice reached 95% within 12 days, which demonstrated the excellent antibacterial properties and wound healing efficacy of PDA@Ag/SerMA microneedles at cellular and animal levels, providing a potential solution for treating DFU.

3.
Sci Rep ; 14(1): 20913, 2024 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-39245773

RESUMEN

Cytokine storm (CS) emerges as an exacerbated inflammatory response triggered by various factors such as pathogens and excessive immunotherapy, posing a significant threat to life if left unchecked. Quercetin, a monomer found in traditional Chinese medicine, exhibits notable anti-inflammatory and antiviral properties. This study endeavors to explore whether quercetin intervention could mitigate CS through a combination of network pharmacology analysis and experimental validation. First, common target genes and potential mechanisms affected by quercetin and CS were identified through network pharmacology, and molecular docking experiments confirmed quercetin and core targets. Subsequently, in vitro experiments of Raw264.7 cells stimulated by lipopolysaccharide (LPS) showed that quercetin could effectively inhibit the overexpression of pro-inflammatory mediators and regulate the AKT1-FoxO1 signaling pathway. At the same time, quercetin can reduce ROS through the Keap1-Nrf2 signaling pathway. In addition, in vivo studies of C57BL/6 mice injected with LPS further confirmed quercetin's inhibitory effect on CS. In conclusion, this investigation elucidated novel target genes and signaling pathways implicated in the therapeutic effects of quercetin on CS. Moreover, it provided compelling evidence supporting the efficacy of quercetin in reversing LPS-induced CS, primarily through the regulation of the AKT1-FoxO1 and Keap1-Nrf2 signaling pathways.


Asunto(s)
Proteína Forkhead Box O1 , Proteína 1 Asociada A ECH Tipo Kelch , Lipopolisacáridos , Macrófagos , Factor 2 Relacionado con NF-E2 , Proteínas Proto-Oncogénicas c-akt , Quercetina , Transducción de Señal , Quercetina/farmacología , Animales , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Ratones , Factor 2 Relacionado con NF-E2/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína Forkhead Box O1/metabolismo , Células RAW 264.7 , Macrófagos/metabolismo , Macrófagos/efectos de los fármacos , Ratones Endogámicos C57BL , Síndrome de Liberación de Citoquinas/tratamiento farmacológico , Síndrome de Liberación de Citoquinas/metabolismo , Síndrome de Liberación de Citoquinas/prevención & control , Simulación del Acoplamiento Molecular , Especies Reactivas de Oxígeno/metabolismo
4.
Discov Oncol ; 15(1): 131, 2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39304557

RESUMEN

BACKGROUND: Prostate cancer (PCa) represents a significant health challenge for men, and the advancement of the disease often results in a grave prognosis for patients. Therefore, the identification of biomarkers associated with the diagnosis and prognosis of PCa holds paramount importance in patient health management. METHODS: The datasets pertaining to PCa were retrieved from the Gene Expression Omnibus (GEO) database. Weighted gene co-expression network analysis (WGCNA) was conducted to investigate the modules specifically associated with the diagnosis of PCa. The hub genes were identified using the LASSO regression analysis. The expression levels of these hub genes were further validated by qRT-PCR experiments. Receiver operating characteristic (ROC) curves and nomograms were employed as evaluative measures for assessing the diagnostic value. RESULTS: The blue module identified by WGCNA exhibited a strong association with PCa. Six hub genes (SLC14A1, COL4A6, MYOF, FLRT3, KRT15, and LAMB3) were identified by LASSO regression analysis. Further verification confirmed that these six genes were significantly downregulated in tumor tissues and cells. The six hub genes and the nomogram demonstrated substantial diagnostic value, with area under the curve (AUC) values ranging from 0.754 to 0.961. Moreover, patients with low expression levels of these six genes exhibited elevated T/N pathological stage and Gleason score, implying a more advanced disease state. Meanwhile, their progression-free survival (PFS) was observed to be potentially poorer. Finally, a significant association could be observed between the expression of these genes and the dysregulation of immune cells, along with drug sensitivity. CONCLUSIONS: In summary, our study identified six hub genes, namely SLC14A1, COL4A6, MYOF, FLRT3, KRT15, and LAMB3, which can be utilized to establish a diagnostic model for PCa. The discovery may offer potential molecular targets for clinical diagnosis and treatment of PCa.

5.
BMC Med Genomics ; 17(1): 210, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39138470

RESUMEN

BACKGROUND: Prostate cancer (PCa) stands as the second most prevalent malignancy impacting male health, and the disease's evolutionary course presents formidable challenges in the context of patient treatment and prognostic management. Charged multivesicular body protein 4 C (CHMP4C) participates in the development of several cancers by regulating cell cycle functions. However, the role of CHMP4C in prostate cancer remains unclear. METHODS: In terms of bioinformatics, multiple PCa datasets were employed to scrutinize the expression of CHMP4C. Survival analysis coupled with a nomogram approach was employed to probe into the prognostic significance of CHMP4C. Gene set enrichment analysis (GSEA) was conducted to interrogate the functional implications of CHMP4C. In terms of cellular experimentation, the verification of RNA and protein expression levels was executed through the utilization of qRT-PCR and Western blotting. Upon the establishment of a cell line featuring stable CHMP4C knockdown, a battery of assays, including Cell Counting Kit-8 (CCK-8), wound healing, Transwell, and flow cytometry, were employed to discern the impact of CHMP4C on the proliferation, migration, invasion, and cell cycle function of PCa cells. RESULTS: The expression of CHMP4C exhibited upregulation in both PCa cells and tissues, and patients demonstrating elevated CHMP4C expression levels experienced a notably inferior prognosis. The nomogram, constructed using CHMP4C along with clinicopathological features, demonstrated a commendable capacity for prognostic prediction. CHMP4C knockdown significantly inhibited the proliferation, migration, and invasion of PCa cells (LNcaP and PC3). CHMP4C could impact the advancement of the PCa cell cycle, and its expression might be regulated by berberine. Divergent CHMP4C expression among PCa patients could induce alterations in immune cell infiltration and gene mutation frequency. CONCLUSIONS: Our findings suggest that CHMP4C might be a prognostic biomarker in PCa, potentially offering novel perspectives for the advancement of precision therapy for PCa.


Asunto(s)
Ciclo Celular , Proliferación Celular , Neoplasias de la Próstata , Humanos , Masculino , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/metabolismo , Pronóstico , Ciclo Celular/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Movimiento Celular/genética , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Complejos de Clasificación Endosomal Requeridos para el Transporte/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Nomogramas
6.
J Hazard Mater ; 478: 135531, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39178782

RESUMEN

Microplastics (MPs) pose significant concerns for marine ecological security due to their minuteness and ubiquity. However, comprehensive knowledge on their distribution and fate in seawater columns remains limited. This study investigated the abundances and characteristics of MPs across 3-6 water layers in the South Yellow Sea and East China Sea. Results indicate that high-abundance small MPs (< 100 µm) (average 6567 items/m3) were hidden beneath the sea-surface, predominantly fine-grained particles (< 20 µm) and high-density polymers (> 1.03 g/cm3). The total suspended MPs (5.0-834.2 µm) are estimated at 2.9-3.1 × 1017 particles, with most of them occurring in upper layers. In profiles, their distribution varied by physical properties with depth; fragment-shaped and high-density MPs increased in proportion at greater depths, contrasting with fibrous MPs. These MPs originated primarily from the Yangtze River and their winter transport was driven by the Yangtze River Dilution Water, East China Sea Coastal Current, and Yellow Sea Warm Current, resulting in their accumulation in coastal and estuarine regions. Consequently, the Yangtze River Estuary ecosystem faces substantial risks from MP pollution throughout the water column. This work unveils the prevalence of small MPs in coastal water columns and intricate interaction between their fate and hydrodynamic conditions.

7.
J Hazard Mater ; 478: 135608, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39180996

RESUMEN

This study addresses the need for high-performance and sustainable air filters by developing a bio-based, high-efficiency particulate air (HEPA) filter. Current HEPA filters often rely on non-biodegradable materials, creating environmental burdens. In this paper, we presented a HEPA filter fabricated from natural basalt fiber (BF) and nanocellulose fiber. The developed filter featured a sandwich structure with electrospun nanocellulose fiber deposited onto a base BF layer, followed by a second BF layer and heat treatment. Various techniques were employed to characterize the obtained sample, and the results showed that the nonwoven BF fabric significantly reduced the pressure drop of the filter by up to 60 %. The nanocellulose fiber played a crucial role in achieving a remarkable filtration efficiency of 99.99 % for PM0.3. BF-based filter demonstrated exceptional fire resistance, hydrophobia, durability, and ease of cleaning, maintaining its effectiveness at temperatures up to 150 °C. Notably, it exhibited significantly better biodegradability than commercially available HEPA filters. By employing a hierarchical structure of sustainable basalt and cellulose fibers, this study paved the way for the development of next-generation hazardous particulate matter filters with exceptional performance in harsh conditions and reduced environmental impact.

8.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(4): 1186-1190, 2024 Aug.
Artículo en Chino | MEDLINE | ID: mdl-39192417

RESUMEN

OBJECTIVE: To observe the genetic variation of SH2B3 in patients with myeloid neoplasms. METHODS: The results of targeted DNA sequencing associated with myeloid neoplasms in the Department of Hematology, Xuanwu Hospital, Capital Medical University from November 2017 to November 2022 were retrospectively analyzed, and the patients with SH2B3 gene mutations were identified. The demographic and clinical data of these patients were collected, and characteristics of SH2B3 gene mutation, co-mutated genes and their correlations with diseases were analyzed. RESULTS: The sequencing results were obtained from 1 005 patients, in which 19 patients were detected with SH2B3 gene mutation, including 18 missense mutations (94.74%), 1 nonsense mutation (5.26%), and 10 patients with co-mutated genes (52.63%). Variant allele frequency (VAF) ranged from 0.03 to 0.66. The highest frequency mutation was p.Ile568Thr (5/19, 26.32%), with an average VAF of 0.49, involving 1 case of MDS/MPN-RS (with SF3B1 mutation), 1 case of MDS-U (with SF3B1 mutation), 1 case of aplastic anemia with PNH clone (with PIGA and KMT2A mutations), 2 cases of MDS-MLD (1 case with SETBP1 mutation). The other mutations included p.Ala567Thr in 2 cases (10.53%), p.Arg566Trp, p.Glu533Lys, p.Met437Arg, p.Arg425Cys, p.Glu314Lys, p.Arg308*, p.Gln294Glu, p.Arg282Gln, p.Arg175Gln, p.Gly86Cys, p.His55Asn and p.Gln54Pro in 1 case each. CONCLUSION: A wide distribution of genetic mutation sites and low recurrence of SH2B3 is observed in myeloid neoplasms, among of them, p.Ile568Thr mutation is detected with a higher incidence and often coexists with characteristic mutations of other diseases.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Péptidos y Proteínas de Señalización Intracelular , Mutación , Humanos , Proteínas Adaptadoras Transductoras de Señales/genética , Estudios Retrospectivos , Péptidos y Proteínas de Señalización Intracelular/genética , Variación Genética , Frecuencia de los Genes , Mutación Missense , Trastornos Mieloproliferativos/genética , Masculino , Neoplasias Hematológicas/genética
9.
Angew Chem Int Ed Engl ; : e202413600, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136072

RESUMEN

Achieving high energy density has always been the goal of lithium-ion batteries (LIBs). SiOx has emerged as a compelling candidate for use as a negative electrode material due to its remarkable capacity. However, the huge volume expansion and the unstable electrode interface during (de)lithiation, hinder its further development. Herein, we report a facile strategy for the synthesis of surface fluorinated SiOx (SiOx@vG-F), and investigate their influences on battery performance. Systematic experiments investigations indicate that the reaction between Li+ and fluorine groups promotes the in-situ formation of stable LiF-rich solid electrolyte interface (SEI) on the surface of SiOx@vG-F anode, which effectively suppresses the pulverization of microsized SiOx particles during the charge and discharge cycle. As a result, the SiOx@vG-F enabled a higher capacity retention of 86.4% over 200 cycles at 1.0 C in the SiOx@vG-F||LiNi0.8Co0.1Mn0.1O2 full cell. This approach will provide insights for the advancement of alternative electrode materials in diverse energy conversion and storage systems.

10.
World J Psychiatry ; 14(7): 1095-1105, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39050201

RESUMEN

BACKGROUND: Autism spectrum disorder (ASD) is a developmental disorder characterized by social deficits and repetitive behavior. Gastrointestinal (GI) problems, such as constipation, diarrhea, and inflammatory bowel disease, commonly occur in patients with ASD. Previously, GI problems of ASD patients were attributed to intestinal inflammation and vertical mother-to-infant microbiome transmission. AIM: To explore whether GI problems in ASD are related to maternal intestinal inflammation and gut microbiota abnormalities. METHODS: An ASD rat model was developed using valproic acid (VPA). Enzyme-linked immunosorbent assay and fecal 16S rRNA sequencing were used to test GI changes. RESULTS: VPA exposure during pregnancy led to pathological maternal intestinal changes, resulting in alterations in maternal gut microbiota. Additionally, the levels of inflammatory factors also increased. Moreover, prenatal exposure to VPA resulted in impaired duodenal motility in the offspring as well as increased levels of inflammatory factors. CONCLUSION: GI problems in ASD may be associated with maternal intestinal inflammation and microbiota abnormality. Future research is required to find more evidence on the etiology and treatment of GI problems in ASD.

11.
Front Public Health ; 12: 1414903, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39045167

RESUMEN

Background: Type 2 diabetes(T2DM) is a global health problem which is accompanied with multi-systemic complications, and associated with long-term health burden and economic burden. Effective health seeking behavior (HSB) refers to reasonably utilize health resources, effectively prevent and treat diseases, and maintain health. Effective health seeking behavior (HSB) is vital to mitigate the risk of T2DM complications. However, health seeking behavior for T2DM patients remains sub-optimal worldwide. Objective: The study aimed to explore the internal logic of how health seeking behavior of T2DM patients develops and the influencing factors of health seeking behavior. With a view to provide a reference basis for improving the health seeking behavior situation of T2DM patients. Methods: This study was conducted at an integrated tertiary hospital in China. People who were diagnosed with T2DM, capable of expressing clearly and had no mental illness, were approached based on a purposive sampling. The experience of T2DM and health seeking behavior were collected via in-depth interviews. A theory-driven thematic analysis based on Health Belief Model (HBM) was applied for data analysis. Inductive reasoning was used to identify emerging themes which were not included in HBM. Results: 26 patients with T2DM were included in the current study. Seven themes were identified, including: (1) T2DM diagnosis and severity; (2) T2DM treatment and management; (3) Perceived susceptibility of diabetes progression; (4) Perceived severity of diabetes progression; (5) Perceived benefits of health seeking behavior; (6) Perceived barriers of health seeking behavior; (7) Perception of behavioral cues. Generally, patients with T2DM lacked reliable sources of information, considered T2DM to be slow-progressing and without posing an immediate threat to life. Consequently, they did not fully grasp the long-term risks associated with T2DM or the protective effects of health seeking behavior. Conclusion: This study highlighted the challenges in health seeking behavior for patients with T2DM. It suggested that future interventions and strategies should involve multi-faceted approaches, targeting healthcare providers (HCPs), patients with T2DM, and their support networks. This comprehensive strategy can help patients better understand their condition and the importance of effective health seeking behavior. Ultimately, enhancing their capacity for adopting appropriate health-seeking practices.


Asunto(s)
Diabetes Mellitus Tipo 2 , Modelo de Creencias sobre la Salud , Aceptación de la Atención de Salud , Investigación Cualitativa , Humanos , Diabetes Mellitus Tipo 2/psicología , Masculino , Femenino , Persona de Mediana Edad , China , Aceptación de la Atención de Salud/estadística & datos numéricos , Aceptación de la Atención de Salud/psicología , Adulto , Anciano , Conductas Relacionadas con la Salud , Entrevistas como Asunto
12.
Mol Cell Biochem ; 479(7): 1553-1570, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38856795

RESUMEN

Epigenetics encompasses reversible and heritable chemical modifications of non-nuclear DNA sequences, including DNA and RNA methylation, histone modifications, non-coding RNA modifications, and chromatin rearrangements. In addition to well-studied DNA and histone methylation, RNA methylation has emerged as a hot topic in biological sciences over the past decade. N6-methyladenosine (m6A) is the most common and abundant modification in eukaryotic mRNA, affecting all RNA stages, including transcription, translation, and degradation. Advances in high-throughput sequencing technologies made it feasible to identify the chemical basis and biological functions of m6A RNA. Dysregulation of m6A levels and associated modifying proteins can both inhibit and promote cancer, highlighting the importance of the tumor microenvironment in diverse biological processes. Gastrointestinal tract cancers, including gastric, colorectal, and pancreatic cancers, are among the most common and deadly malignancies in humans. Growing evidence suggests a close association between m6A levels and the progression of gastrointestinal tumors. Global m6A modification levels are substantially modified in gastrointestinal tumor tissues and cell lines compared to healthy tissues and cells, possibly influencing various biological behaviors such as tumor cell proliferation, invasion, metastasis, and drug resistance. Exploring the diagnostic and therapeutic potential of m6A-related proteins is critical from a clinical standpoint. Developing more specific and effective m6A modulators offers new options for treating these tumors and deeper insights into gastrointestinal tract cancers.


Asunto(s)
Adenosina , Neoplasias Gastrointestinales , Humanos , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/genética , Neoplasias Gastrointestinales/genética , Neoplasias Gastrointestinales/patología , Neoplasias Gastrointestinales/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Epigénesis Genética , Metilación
13.
J Hazard Mater ; 475: 134911, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38889457

RESUMEN

1-Nitropyrene (1-NP) is a neurodevelopmental toxicant. This study was to evaluate the impact of exposure to 1-NP after weaning on anxiety-like behavior. Five-week-old mice were administered with 1-NP (0.1 or 1 mg/kg) daily for 4 weeks. Anxiety-like behaviour was measured using elevated-plus maze (EPM) and open field test (OFT). In EPM test, time spending in open arm and times entering open arm were reduced in 1-NP-treated mice. In OFT test, time spent in the center region and times entering the center region were diminished in 1-NP-treated mice. Prefrontal dendritic length and number of dendrite branches were decreased in 1-NP-treated mice. Prefrontal PSD95, an excitatory postsynaptic membrane protein, and gephyrin, an inhibitory postsynaptic membrane protein, were downregulated in 1-NP-treated mice. Further analysis showed that peripheral steroid hormones, including serum testosterone (T) and estradiol (E2), testicular T, and ovarian E2, were decreased in 1-NP-treated mice. Interestingly, T and E2 were diminished in 1-NP-treated prefrontal cortex. Prefrontal T and E2 synthases were diminished in 1-NP-treated mice. Mechanistically, GCN2-eIF2α, a critical pathway that regulates ribosomal protein translation, was activated in 1-NP-treated prefrontal cortex. These results indicate that exposure to 1-NP after weaning induces anxiety-like behaviour partially by inhibiting steroid hormone synthesis in prefrontal cortex.


Asunto(s)
Ansiedad , Corteza Prefrontal , Pirenos , Destete , Animales , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Ansiedad/inducido químicamente , Masculino , Pirenos/toxicidad , Femenino , Ratones , Conducta Animal/efectos de los fármacos , Testosterona/sangre , Estradiol
14.
Org Lett ; 26(25): 5396-5401, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38870323

RESUMEN

A stereodivergent synthesis of ß- and α-O-glycosides using 3-O-quinaldoyl glucals was developed by palladium catalysis at 60 and 110 °C respectively. Various alcohols, monosaccharides, and amino acid were glycosylated to form ß- and α- products in good yields with high stereoselectivity. Mechanistic studies indicated no classic Pd-N (quinoline) coordination, but π-π stacking interactions promoted the anomeric stereodiversity. The practicality was demonstrated by glycosylating natural products/drugs and synthesizing a complex tetrasaccharide.

15.
J Am Chem Soc ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38847614

RESUMEN

Axially chiral biaryls featuring a C-N axis are important functional molecules in diverse fields. The asymmetric Buchwald-Hartwig reaction represents a powerful strategy for these targets. Previous studies, however, have been predominantly restricted to intramolecular atroposelective coupling, likely due to the steric and entropic effects in the reductive elimination of Pd(II) species with sterically congested aryl and nitrogen groups. We now report two intermolecular Buchwald-Hartwig coupling systems of bulky NH lactams and halohydrocarbons enabled by rerouting the mechanism of C-N reductive elimination to one that accommodates sterically challenging substrates. Both atroposelective coupling systems exhibited functional group tolerance, excellent enantioselectivity, and high Z selectivity (if applicable), affording C-N atropisomeric biaryl and olefins through de novo construction of a C-N chiral axis. Experimental and computational studies were performed to elucidate the mechanism, and the switch of the reaction pathways is traced to the steric effect (ortho substituent) of the aryl halide substrate. A bulky 2,6-disubstituted aryl halide reorients the proximal lactamide ligand to its unusual O-ligation mode. With the amide oxygen participation, this intermediate undergoes C-N reductive elimination with an accessible barrier through a five-membered ring transition state, a pathway as well as a chiral induction mode that has been much underexplored in asymmetric catalysis.

16.
Artículo en Inglés | MEDLINE | ID: mdl-38848229

RESUMEN

Data clustering is a fundamental machine learning task that seeks to categorize a dataset into homogeneous groups. However, real data usually contain noise, which poses significant challenges to clustering algorithms. In this article, motivated by how the k -means algorithm is derived from a Gaussian mixture model (GMM), we propose a robust k -means-type algorithm, named k -means-type clustering based on t -distribution (KMTD), by assuming that the data points are drawn from a special multivariate t -mixture model (TMM). Compared to the Gaussian distribution, the t -distribution has a fatter tail. The proposed algorithm is more robust to noise. Like the k -means algorithm, the proposed algorithm is simpler than those based on a full TMM. Both synthetic and actual data are used to illustrate the proposed algorithm's performance and efficiency. The experimental results demonstrated that the proposed algorithm operates more quickly than other sophisticated algorithms and, in most cases, achieves higher accuracy than the other algorithms.

17.
Biomed Opt Express ; 15(5): 3076-3091, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38855692

RESUMEN

This research presents a novel approach for the dynamic monitoring of onion-like carbon nanoparticles inside colorectal cancer cells. Onion-like carbon nanoparticles are widely used in photothermal cancer therapy, and precise 3D tracking of their distribution is crucial. We proposed a limited-angle digital holographic tomography technique with unsupervised learning to achieve rapid and accurate monitoring. A key innovation is our internal learning neural network. This network addresses the information limitations of limited-angle measurements by directly mapping coordinates to measured data and reconstructing phase information at unmeasured angles without external training data. We validated the network using standard SiO2 microspheres. Subsequently, we reconstructed the 3D refractive index of onion-like carbon nanoparticles within cancer cells at various time points. Morphological parameters of the nanoparticles were quantitatively analyzed to understand their temporal evolution, offering initial insights into the underlying mechanisms. This methodology provides a new perspective for efficiently tracking nanoparticles within cancer cells.

18.
Mol Med Rep ; 30(1)2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38785151

RESUMEN

Periodontal disease is a common infectious disease that can lead to the loss of teeth. Hower how to effectively suppress the inflammation with medication is unclear. The aim of the present study was to investigate the anti­inflammatory effect of Oroxylin A in periodontitis and its potential role through heme oxygenase­1 (HO­1). Primary rat gingival fibroblasts (RGFs) were cultured using the tissue block method and identified by immunofluorescence. Following lipopolysaccharide (LPS) stimulation of RGFs, Oroxylin A was administered at 50, 100, 200 or 400 µg/ml. Reverse transcription­quantitative PCR was used to assess mRNA expression of cyclooxygenase (COX)­2, TNF­α, RANKL and osteoprotegerin (OPG). Western blotting was used to detect protein expression levels of COX ­2, TNF­α, RANKL and OPG. Following HO­1 knockdown, the same treatment was performed. The expression of COX­2 in rat gingival tissue was observed by immunohistochemistry. One­way analysis of variance and Student's t test were used for statistical analysis. Oroxylin A downregulated mRNA expression of COX­2, TNF­α, RANKL and OPG in LPS­induced RGFs. With increase of Oroxylin A dose, the expression of HO­1 was gradually upregulated. When HO­1 was knocked down, Oroxylin A did not downregulate the expression of COX­2, TNF­α, RANKL and OPG in LPS­induced RGFs. Immunohistochemical results showed that expression of COX­2 was downregulated by Oroxylin A, and the expression of TNF­α, RANKL and OPG were also downregulated. Oroxylin A decreased expression of inflammatory cytokines in LPS­induced RGFs and had a good inhibitory effect on periodontitis in rats.


Asunto(s)
Ciclooxigenasa 2 , Fibroblastos , Flavonoides , Periodontitis , Ligando RANK , Animales , Ratas , Flavonoides/farmacología , Periodontitis/metabolismo , Periodontitis/tratamiento farmacológico , Periodontitis/patología , Ligando RANK/metabolismo , Ligando RANK/genética , Masculino , Ciclooxigenasa 2/metabolismo , Ciclooxigenasa 2/genética , Fibroblastos/metabolismo , Fibroblastos/efectos de los fármacos , Osteoprotegerina/metabolismo , Osteoprotegerina/genética , Lipopolisacáridos , Encía/metabolismo , Encía/efectos de los fármacos , Factor de Necrosis Tumoral alfa/metabolismo , Citocinas/metabolismo , Hemo-Oxigenasa 1/metabolismo , Hemo-Oxigenasa 1/genética , Células Cultivadas , Ratas Sprague-Dawley
19.
Int J Med Sci ; 21(7): 1250-1256, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38818475

RESUMEN

Background: Recovery time is a crucial factor in ensuring the safety and effectiveness of both patients and endoscopy centers. Propofol is often preferred due to its fast onset and minimal side effects. Remimazolam is a new intravenous sedative agent, characterized by its rapid onset of action, quick recovery and organ-independent metabolism. Importantly, its effect can be specifically antagonized by flumazenil. The primary goal of this study is to compare the recovery time of remimazolam besylate and propofol anesthesia during endoscopic procedures in elderly patients. Methods: 60 patients aged 65-95 years who underwent gastrointestinal endoscopy were randomly and equally assigned to two groups: the remimazolam group (Group R) and the propofol group (Group P). The primary measure was the recovery time, defined as the time from discontinuing remimazolam or propofol until reaching an Observer's Assessment of Alertness and Sedation scale (OAA/S) score of 5 (responds readily to name spoken in normal tone). The time required to achieve an OAA/S score of 3 (responds after name spoken loudly or repeatedly along with glazed marked ptosis) was also recorded and compared. Results: The recovery time for Group R (2.6 ± 1.6 min) was significantly shorter than that for Group P (10.8 ± 3.0 min), with a 95% confidence interval (CI): 6.949-9.431 min, p <0.001. Similarly, the time to attain an OAA/S score of 3 was significantly less in Group R (1.6 ± 0.9 min) compared to Group P (9.6 ± 2.6 min), with a 95% CI: 6.930-8.957 min, p <0.001. Conclusion: Our study demonstrated that remimazolam anesthesia combined with flumazenil antagonism causes a shorter recovery time for elderly patients undergoing gastrointestinal endoscopy compared to propofol. Remimazolam followed by flumazenil antagonism provides a promising alternative to propofol for geriatric patients, particularly during gastrointestinal endoscopy.


Asunto(s)
Periodo de Recuperación de la Anestesia , Benzodiazepinas , Endoscopía Gastrointestinal , Hipnóticos y Sedantes , Propofol , Humanos , Anciano , Propofol/administración & dosificación , Masculino , Femenino , Anciano de 80 o más Años , Endoscopía Gastrointestinal/métodos , Hipnóticos y Sedantes/administración & dosificación , Hipnóticos y Sedantes/efectos adversos , Benzodiazepinas/uso terapéutico
20.
Nano Lett ; 24(22): 6585-6591, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38785400

RESUMEN

The gallium-doped hafnium oxide (Ga-HfO2) films with different Ga doping concentrations were prepared by adjusting the HfO2/Ga2O3 atomic layer deposition cycle ratio for high-speed and low-voltage operation in HfO2-based ferroelectric memory. The Ga-HfO2 ferroelectric films reveal a finely modulated coercive field (Ec) from 1.1 (HfO2/Ga2O3 = 32:1) to an exceptionally low 0.6 MV/cm (HfO2/Ga2O3 = 11:1). This modulation arises from the competition between domain nucleation and propagation speed during polarization switching, influenced by the intrinsic domain density and phase dispersion in the film with specific Ga doping concentrations. Higher Ec samples exhibit a nucleation-dominant switching mechanism, while lower Ec samples undergo a transition from a nucleation-dominant to a propagation-dominant reversal mechanism as the electric field increases. This work introduces Ga as a viable dopant for low Ec and offers insights into material design strategies for HfO2-based ferroelectric memory applications.

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