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1.
Nano Lett ; 24(1): 519-524, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38126338

RESUMEN

This work demonstrates that targeting ligand density on nanoparticles can affect interactions between the nanoconstructs and cell membrane receptors. We discovered that when the separation between covalently grafted DNA aptamers on gold nanostars was comparable to the distance between binding sites on a receptor dimer (matched density; MD), nanoconstructs exhibited a higher selectivity for binding to the dimeric form of the protein. Single-particle dynamics of MD nanoconstructs showed slower rotational rates and larger translational footprints on cancer cells expressing more dimeric forms of receptors (dimer+) compared with cells having more monomeric forms (dimer-). In contrast, nanoconstructs with either increased (nonmatched density; NDlow) or decreased ligand spacing (NDhigh) had minimal changes in dynamics on either dimer+ or dimer- cells. Real-time, single-particle analyses can reveal the importance of nanoconstruct ligand density for the selective targeting of membrane receptors in live cells.


Asunto(s)
Nanopartículas , Ligandos , Membrana Celular/metabolismo , Nanopartículas/química , Polímeros/metabolismo , Sitios de Unión
2.
Org Biomol Chem ; 22(21): 4364-4368, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38738449

RESUMEN

This manuscript describes the synthesis of γ-lactam from the nitrogen insertion reaction of cyclobutanones using an oxime as an aminating reagent with a catalytic amount of Brønsted acid. This method was employed with a more stable oxime reagent, which is a precursor analog of hydroxylamine derivatives with explosive properties. The reaction was tolerated by various substituted cyclobutanones and less strained five- or six-membered ketones. The obtained γ-lactam products could be transformed into γ-aminobutyric acid derivatives via ring-opening hydrolysis. The reaction mechanism is discussed from the perspective of the isotope effect, etc.

3.
BMC Cardiovasc Disord ; 24(1): 370, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39020323

RESUMEN

BACKGROUND: Anomalous aortic origin of a coronary artery from the inappropriate sinus of Valsalva (AAOCA) is a rare congenital heart lesion. It is uncommon for patients with AAOCA to present with severe symptoms at a very young age. CASE PRESENTATION: We describe a very rare but critical presentation in a young infant with AAOCA that requires surgical repair and pacemaker placement. A three-month-old infant was referred because of syncope. Cardiac arrest occurred shortly after admission. The electrocardiogram indicated a complete atrioventricular block and a transvenous temporary pacemaker was implanted. A further coronary computed tomographic angiography (CTA) showed the anomalous origin of the right coronary artery from the left sinus of Valsalva. Coronary artery unroofing was performed due to an interarterial course with the intramural component, and a permanent epicardial pacemaker was implanted. The postoperative recovery was uneventful, and this patient was thriving and asymptomatic at the nine-month follow-up. However, the electrocardiogram still indicated a complete pacing rhythm. CONCLUSIONS: By timely diagnosis and treatment, this patient is successfully rescued. Although rare, AAOCA may be fatal even in infants.


Asunto(s)
Estimulación Cardíaca Artificial , Anomalías de los Vasos Coronarios , Marcapaso Artificial , Humanos , Lactante , Anomalías de los Vasos Coronarios/complicaciones , Anomalías de los Vasos Coronarios/diagnóstico por imagen , Anomalías de los Vasos Coronarios/terapia , Anomalías de los Vasos Coronarios/cirugía , Resultado del Tratamiento , Bloqueo Atrioventricular/diagnóstico , Bloqueo Atrioventricular/etiología , Bloqueo Atrioventricular/terapia , Bloqueo Atrioventricular/fisiopatología , Seno Aórtico/diagnóstico por imagen , Seno Aórtico/anomalías , Seno Aórtico/cirugía , Seno Aórtico/fisiopatología , Paro Cardíaco/etiología , Paro Cardíaco/terapia , Paro Cardíaco/diagnóstico , Angiografía Coronaria , Masculino , Electrocardiografía , Angiografía por Tomografía Computarizada
4.
Clin Exp Dermatol ; 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38641554

RESUMEN

BACKGROUND: Photodynamic therapy (PDT) has been strongly recommended as an excellent alternative treatment for Bowen's disease (BD). However, reported data on 5-aminolevulinic acid-mediated PDT (ALA-PDT) with red light irradiation are limited and the long-term effectiveness remains to be determined, especially in dark-skinned populations. METHODS: Medical records of BD patients who received ALA-PDT with red light irradiation between February 2011 and June 2021 were reviewed and summarized. Univariate and multivariate analyses of clinically relevant variables that may affect treatment outcomes were performed to identify risk predictors. RESULTS: The overall clearance rate of 122 BD lesions was 89.3% with a median follow-up time of 36 months. The correlation between the effectiveness and fluorescence intensity of pre-PDT or PDT sessions was statistically significant after eliminating the interference of confounding factors. All recurrences occurred in the first two years following ALA-PDT. CONCLUSION: ALA-PDT is an effective treatment for BD in the skin of color patients. Well-executed operation and effective pre-treatment are the determinants of effectiveness. Fluorescence intensity of pre-PDT appeared to be a significant predictor of final effectiveness. In addition, two years of follow-up is necessary following ALA-PDT.

5.
Pediatr Cardiol ; 2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38602518

RESUMEN

The relationships between maternal exposure to endocrine-disrupting chemicals (EDCs) and congenital heart diseases (CHD) are not elucidated yet. The exposure levels of EDCs are generally estimated based on self-reported questionnaires or occupational exposure evaluations in the literature. Therefore, a study based on epidemiological data from human biospecimens is required to provide stronger evidence between maternal exposure to EDC and CHD. Embase, Pubmed, Scopus, and the Cochrane Library databases were searched for related research which provided risk estimates regarding the relationships between maternal EDC exposure and CHD in human offspring. Baseline characteristics and outcomes of CHD were extracted from each included study. Odds ratios (ORs) with 95% confidence intervals (CIs) were pooled to calculate the overall estimates of CHD. Subgroup and meta-regression analyses were performed to identify the sources of heterogeneity. Bootstrapping techniques were used in analyses where several studies originated from a similar population. A total of seventeen studies were involved in the meta-analyses. Maternal EDC exposure was significantly related to CHD in offspring (OR 2.15; 95%CI 1.64 to 2.83). EDC exposure was significantly associated with septal defects (OR 2.34; 95%CI 1.77 to 3.10), conotruncal defects (OR 2.54; 95%CI 1.89 to 3.43), right ventricular outflow tract obstruction (OR 2.65; 95%CI 1.73 to 4.07), left ventricular outflow tract obstruction (OR 3.58; 95%CI 2.67 to 4.79), anomalous pulmonary venous return (OR 2.31; 95%CI 1.34 to 4.00), and other heart defects (OR 2.49; 95%CI 1.75 to 3.54). In addition, maternal exposure to heavy metals, which included lead (OR 2.19; 95%CI 1.29 to 3.71), cadmium (OR 1.81; 95%CI 1.28 to 2.56), mercury (OR 2.23; 95%CI 1.13 to 4.44), and manganese (OR 2.65; 95%CI 1.48 to 4.74), increased risks for CHD significantly. In conclusion, based on the latest evidence, maternal EDC exposure may increase CHD risks in human offspring, especially in heavy metal exposure conditions.

6.
Environ Toxicol ; 39(2): 952-964, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37975621

RESUMEN

Di(2-ethylhexyl) phthalate (DEHP), an environmental endocrine disruptor, is one of the most common plasticizers and is widely used in various plastic products. DEHP induces apoptosis and oxidative stress and has been shown to have androgenic toxicity. However, the methods to combat DEHP-induced testicular damage and the mechanisms involved remain to be elucidated. In the present study, we used melatonin, which has strong antioxidant properties, to intervene in prepubertal mice and mouse Leydig cells (TM3) treated with DEHP or its metabolite mono(2-ethylhexyl) phthalate (MEHP). The results showed that melatonin protected against DEHP-induced testicular damage in prepubertal mice, mainly by protecting against DEHP-induced structural destruction of the germinal tubules and by attenuating the DEHP-induced decrease in testicular organ coefficients and testosterone levels. Transcriptomic analysis found that melatonin may attenuate DEHP-induced oxidative stress and apoptosis in prepubertal testes. In vitro studies further revealed that MEHP induces oxidative stress injury and increases apoptosis in TM3 cells, while melatonin reversed this damage. In vitro studies also found that MEHP exposure inhibited the expression levels of molecules related to the PI3K/AKT signaling pathway, and melatonin reversed this change. In conclusion, these findings suggest that melatonin protects against DEHP-induced prepubertal testicular injury via the PI3K/AKT signaling pathway, and provide a theoretical basis and experimental rationale for combating male reproductive dysfunction.


Asunto(s)
Dietilhexil Ftalato , Melatonina , Masculino , Ratones , Animales , Testículo , Melatonina/farmacología , Dietilhexil Ftalato/toxicidad , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Estrés Oxidativo , Apoptosis
7.
Nano Lett ; 23(23): 11260-11265, 2023 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-38048438

RESUMEN

This work reports a scaffold-templated, bottom-up synthesis of 3D anisotropic nanofeatures on periodic arrays of gold nanoparticles (AuNPs). Our method relies on substrate-bound AuNPs as large seeds with hemispherical shapes and smooth surfaces after the thermal annealing of as-fabricated particles. Spiky features were grown by immersing the patterned AuNPs into a growth solution consisting of a gold salt and Good's buffer; the number and length of spikes could be tuned by changing the solution pH and buffer concentration. Intermediate structures that informed the growth mechanism were characterized as a function of time by correlating the optical properties and spike features. Large-area (cm2) spiky AuNP arrays exhibited surface-enhanced Raman spectroscopy enhancement that was associated with increased numbers of high-aspect-ratio spikes formed on the AuNP seeds.

8.
Biochem Biophys Res Commun ; 654: 62-72, 2023 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-36889036

RESUMEN

Copper oxide nanoparticles (CuONPs) are metallic multifunctional nanoparticles with good conductive, catalytic and antibacterial characteristics that have shown to cause reproductive dysfunction. However, the toxic effect and potential mechanisms of prepubertal exposure to CuONPs on male testicular development have not been clarified. In this study, healthy male C57BL/6 mice received 0, 10, and 25 mg/kg/d CuONPs by oral gavage for 2 weeks (postnatal day 22-35). The testicular weight was decreased, testicular histology was disturbed and the number of Leydig cells was reduced in all CuONPs-exposure groups. Transcriptome profiling suggested steroidogenesis was impaired after exposure to CuONPs. The steroidogenesis-related genes mRNA expression level, concentration of serum steroids hormones and the HSD17B3-, STAR- and CYP11A1-positive Leydig cell numbers were dramatically reduced. In vitro, we exposed TM3 Leydig cells to CuONPs. Bioinformatic analysis, flow cytometry analysis and western blotting analysis confirmed that CuONPs can dramatically reduce Leydig cells viability, enhance apoptosis, trigger cell cycle arrest and reduce cell testosterone levels. U0126 (ERK1/2 inhibitor) significantly reversed TM3 Leydig cells injury and testosterone level decrease induced by CuONPs. These outcomes indicate that CuONPs exposure activates the ERK1/2 signaling pathway, which further promotes apoptosis and cell cycle arrest in TM3 Leydig cells, and ultimately leads to Leydig cells injury and steroidogenesis disorders.


Asunto(s)
Células Intersticiales del Testículo , Nanopartículas del Metal , Ratones , Animales , Masculino , Células Intersticiales del Testículo/metabolismo , Testículo/metabolismo , Testosterona/metabolismo , Cobre/metabolismo , Ratones Endogámicos C57BL , Nanopartículas del Metal/toxicidad , Óxidos/farmacología
9.
Chem Rec ; 23(12): e202300238, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37698286

RESUMEN

Electron-precise B-B bonded compounds are valuable reagents in organic syntheses, which can be used as key starting material for the synthesis of functionalized organoboranes. Bis(pinacolato)diborane(4) B2 pin2 and its derivatives are among the most studied diboron species. However, their B-B bonds usually need to be activated by transition metal catalysts or bases for further transformations. Recently, many well-designed/reactive electron-precise B-B bonded compounds have been developed, which could facilitate direct reactions with small molecules, unsaturated substrates, and electrophiles. This review highlights the synthesis, structure, and reactivity of neutral and anionic B-B bonded compounds.

10.
Macromol Rapid Commun ; 44(24): e2300382, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37703910

RESUMEN

Organic-inorganic hybrid perovskites have garnered significant attention in optoelectronics owing to their outstanding tunable optical characteristics. Controlled growth of perovskite nanocrystals from solutions is key for controlling the emission intensity and photoluminescence lifetime of perovskites. In particular, most studies have focused on controlling the crystallization of perovskite through chemical treatment using chelating ligands or physical treatment via antisolvent diffusion, and there exists a trade-off between the photoluminescence intensity and lifetime of perovskites. Herein, a selective solvent vapor-assisted crystallization with the aid of a functional polymer, which nanoscale perovskite crystals are grown andante from precursor solution, is presented for tuning the crystallization and optical properties of a common halide perovskite, methylammonium lead bromide (MAPbBr3 ). The proposed method here produces perovskite nanocrystals in the range of 200-300 nm. The spin-coated thin film formed from the perovskite solution exhibits strong green photoluminescence with a long lifetime. The effects of the functional group and polymer dosage on the crystallization of MAPbBr3 are systematically investigated, and the crystallization mechanism is explained based on a modified LaMer model. This study provides an advanced solution process for precisely controlling perovskite crystallization to enhance their optical properties for next-generation optoelectronic devices.


Asunto(s)
Compuestos de Calcio , Gases , Cristalización , Difusión
11.
Bioorg Chem ; 139: 106713, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37459823

RESUMEN

Focal adhesion kinase (FAK), a non-receptor tyrosine kinase, plays a pivotal role in tumor invasion and metastasis. Many FAK inhibitors had been reported, but the development of FAK inhibitors in clinical studies are still limited. To facilitate the discovery of FAK modulators and further elucidate the role of FAK in cancer metastasis, it is necessary to discover a novel, potent and selective FAK inhibitor. In this study, a series of FAK inhibitors with novel scaffold were designed and synthesized based on cyclization strategy. Here, we reported compound 10b (HMC-18NH) with excellent inhibition of FAK (IC50 = 9.9 nM) and anticancer activity against several cancer cell lines including BxPC-3, PANC-1, MCF-7, MDA-MB-231, U-87MG, HepG2, HCT-15 and A549. Extraordinary, compound 10b showed the best cytotoxic effects against A549 with the IC50 value of 0.8 µM. In addition, 10b exhibited effective invasion and migration suppression in A549 cells. Further investigations revealed that compound 10b potently induced and promoted apoptosis in a dose-dependent manner and arrested A549 cells in the G2/M phase. Collectively, these results suggest that 10b is a promising FAK inhibitor and serve as a lead compound which deserve for further optimization.

12.
Network ; 34(3): 151-173, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37246622

RESUMEN

Wind power has been valued by countries for its renewability and cleanness and has become most of the focus of energy development in all countries. However, due to the uncertainty and volatility of wind power generation, making the grid-connected wind power system presents some serious challenges. Improving the accuracy of wind power prediction has become the focus of current research. Therefore, this paper proposes a combined short-term wind power prediction model based on T-LSTNet_markov to improve prediction accuracy. First, perform data cleaning and data preprocessing operations on the original data. Second, forecast using T-LSTNet model in original wind power data. Finally, calculate the error between the forecast value and the actual value. The k-means++ method and Weighted Markov process are used to correct errors and to get the result of the final prediction. The data that are collected from a wind farm in Inner Mongolia Autonomous Region, China, are selected as a case study to demonstrate the effectiveness of the proposed combined models. The empirical results show that the prediction accuracy is further improved after correcting errors.


Asunto(s)
Sistemas de Computación , Incertidumbre , Predicción , Cadenas de Markov , China
13.
Molecules ; 28(12)2023 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-37375352

RESUMEN

Neuronal injury and apoptosis are important causes of the occurrence and development of many neurodegenerative diseases, such as cerebral ischemia, Alzheimer's disease, and Parkinson's disease. Although the detailed mechanism of some diseases is unknown, the loss of neurons in the brain is still the main pathological feature. By exerting the neuroprotective effects of drugs, it is of great significance to alleviate the symptoms and improve the prognosis of these diseases. Isoquinoline alkaloids are important active ingredients in many traditional Chinese medicines. These substances have a wide range of pharmacological effects and significant activity. Although some studies have suggested that isoquinoline alkaloids may have pharmacological activities for treating neurodegenerative diseases, there is currently a lack of a comprehensive summary regarding their mechanisms and characteristics in neuroprotection. This paper provides a comprehensive review of the active components found in isoquinoline alkaloids that have neuroprotective effects. It thoroughly explains the various mechanisms behind the neuroprotective effects of isoquinoline alkaloids and summarizes their common characteristics. This information can serve as a reference for further research on the neuroprotective effects of isoquinoline alkaloids.


Asunto(s)
Alcaloides , Enfermedades Neurodegenerativas , Fármacos Neuroprotectores , Enfermedad de Parkinson , Humanos , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Alcaloides/farmacología , Alcaloides/uso terapéutico , Enfermedades Neurodegenerativas/tratamiento farmacológico , Enfermedad de Parkinson/tratamiento farmacológico , Isoquinolinas/farmacología
14.
Can Assoc Radiol J ; 74(2): 251-263, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36471627

RESUMEN

Purpose: We investigated virtual reality (VR) during a 2-week, undergraduate, radiology elective to determine if it improved learning outcomes and user satisfaction. Methods: Eighteen students enrolled between August 2021 and February 2022. Each student had a collaborative Zoom teaching session with a preceptor using a Picture Archive and Communications System (PACS)-like viewing system Online DICOM Image Navigator (ODIN), followed by a teaching session using a VR, Digital Imaging and Communications in Medicine (DICOM) viewer (SieVRt). After each teaching session, the students independently reviewed 8 imaging cases and completed case related questions. The students completed a survey, rating their subjective experiences using ODIN and SieVRt. Results: There was no difference in total test scores between the two learning strategies. However, students did perform statistically better on two of five questions designed to test the detection/measurement capabilities of SieVRt vs ODIN. Students stated that they preferred using SieVRt over ODIN and agreed that they were able to view subtle imaging findings and abnormalities better using SieVRt. However, students found that some of the functions of SieVRt (measuring angles/lengths, and multitasking) were difficult. There were technical challenges with VR and minor undesirable physical effects (dizziness, nausea, etc.). Conclusions: Virtual reality has the potential to enhance radiology education by providing an immersive and engaging experience. Objectively, students were able to perform two tasks better with SieVRt. Subjectively, the VR platform received favourable reviews from students for a variety of features. There were reported technical and physical challenges related to using VR. Future developments in VR systems should focus on improving the user experience.


Asunto(s)
Radiología , Realidad Virtual , Humanos , Proyectos Piloto , Aprendizaje , Radiografía , Radiología/educación
15.
Phys Rev Lett ; 129(20): 200201, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36462000

RESUMEN

We show that, by using a saturable gain g_{sat}, generalized PT (GPT) symmetry can be achieved in the intrinsically unbalanced (non-PT-symmetric) high-order wireless power transfer systems. A topology decomposition approach is implemented to analyze the parity of the high-order wireless power transfer systems. In the coupling parametric space, a global GPT-symmetric eigenstate is observed along with the spontaneous phase transition of the local GPT-symmetric eigenstates on the exceptional contour. GPT symmetry guarantees a highly efficient and stable power transfer across the distinct coupling regions, which introduces a new paradigm for a broad range of application scenarios involving asymmetric coupling.

16.
Pharmacol Res ; 175: 105985, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34863821

RESUMEN

Diabetic peripheral neuropathy (DPN) is the most common complication of diabetes mellitus and no effective therapy is approved. Here, lycorine, a natural alkaloid, was identified as a potential drug for DPN by the bioinformatics analysis of GEO datasets and Connectivity Map database. Lycorine administration improved peripheral nerve function and autophagy-associated proteins of diabetic mice. Again, in vitro high glucose-cultured rat Schwann cells (RSC96) showed enhanced autophagosome marker LC3-II with the treatment of lycorine. Additionally, beclin-1 and Atg3 were decreased in high glucose-stimulated RSC96 cells, which were reversed by lycorine treatment. Furthermore, DPN-associated differentially expressed genes (DEGs) from GEO datasets and lycorine-drug targets from PubChem and PharmMapper were visually analyzed and revealed that MMP9 was both DPN-associated DEGs and lycorine-drug target. Functional enrichment analysis of MMP9-relevant genes showed that cell energy metabolism was involved. Moreover, lycorine reduced high glucose-enhanced MMP9 expression in RSC96 cells. Overexpression of MMP9 attenuated lycorine-induced the expression of beclin-1, Atg3 and LC3-II in high glucose-cultured RSC96 cells. In addition, AMPK pathway activation was confirmed in lycorine-treated high glucose-cultured RSC96 cells. Then AMPK pathway inhibition attenuated lycorine-reduced MMP9 expression in high glucose-treated RSC96 cells. Molecular docking analysis revealed that lycorine bound the domain of AMPK containing Thr 172 site, which affected AMPK (Thr 172) phosphorylation. Finally, AMPK pathway activation and MMP9 downregulation were also revealed in the sciatic nerves of diabetic mice administrated with lycorine. Taken together, lycorine was advised to promote Schwann cell autophagy via AMPK pathway activation and MMP9 downregulation-induced LC3-II transformation in diabetic peripheral neuropathy.


Asunto(s)
Alcaloides de Amaryllidaceae/uso terapéutico , Neuropatías Diabéticas/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Fenantridinas/uso terapéutico , Nervio Ciático/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/metabolismo , Alcaloides de Amaryllidaceae/farmacología , Animales , Autofagia/efectos de los fármacos , Células Cultivadas , Neuropatías Diabéticas/genética , Neuropatías Diabéticas/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Masculino , Metaloproteinasa 9 de la Matriz/genética , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones Endogámicos C57BL , Fármacos Neuroprotectores/farmacología , Fenantridinas/farmacología , Ratas , Células de Schwann/efectos de los fármacos , Nervio Ciático/fisiología , Transducción de Señal/efectos de los fármacos
17.
Inorg Chem ; 61(24): 8997-9011, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35657382

RESUMEN

A novel family of ruthenium nitrosyl complexes [Ru(bpy)(C∧N)(MeCN)NO](PF6)2 (2a-2e, bpy = 2,2'-bipyridine, HC∧N = 2-phenylpyridine and its derivatives) has been prepared by reacting cyclometalated ruthenium complexes [Ru(bpy)2(C∧N)][PF6] (1a-1e) with NO+, which were comprehensively characterized by mass, IR, NMR, and UV-vis spectra as well as the single-crystal X-ray structure determinations. Herein, the coordination geometry of Ru atoms in 2a-2e is a distorted octahedron and {RuII-NO+}6 is present in these complexes. Theoretical calculations suggest that the reactions involving dissociation of one bipyridine and coordination with NO+ proceed spontaneously (ΔG < 0) and the transformation from 1a-1e to the intermediates is dominated by substituents (ΔGRI varies from -1.19 to -1.53 eV), which influence the binding energy between Ru(II) and NO+ in complexes 2a-2e (-89.42 to -101.17 kcal/mol) and thus control the photorelease of NO on a certain scale. The weak absorption bands in the visible region could be attributed to the contribution of dπ(RuII) → π*(NO+), which were enhanced greatly under light, indicating the possible release of NO. The photoinduced NO, as well as singlet oxygen (1O2), was then confirmed by EPR spectra, and the amount of NO released from 2a-2e was estimated via Griess reagent assay. The cytotoxicity of these complexes with or without visible light irradiation was also investigated using an MTT assay.


Asunto(s)
Compuestos Heterocíclicos , Rutenio , 2,2'-Dipiridil/química , Luz , Rutenio/química , Oxígeno Singlete
18.
Phys Chem Chem Phys ; 24(35): 21131-21140, 2022 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-36039710

RESUMEN

Near-infrared (NIR)-emitting persistent luminescence (PersL) nanoparticles have attracted great attention as a novel optical probe for bioimaging and biosensing applications. These nanoparticles emit long-lasting luminescence after the removal of the excitation source, which effectively eliminates the interference from tissue autofluorescence. Cr-doped zinc gallate (ZnGa2O4:Cr3+, CZGO) is a representative NIR-emitting PersL material. On the other hand, amorphous calcium phosphate (ACP) is a widely used drug carrier due to its high biocompatibility. In this work, we present a design of an ACP-based drug carrier with PersL properties, by forming a CZGO-ACP composite. The PersL properties of CZGO were preserved by composite formation, while it is found that the Zn2+ could migrate from CZGO to ACP during composite formation, leading to different luminescence mechanisms between pure CZGO and the CZGO-ACP composite. The electronic structure of the composite was analyzed by synchrotron X-ray absorption spectroscopy, and a structure-luminescence correlation was proposed.


Asunto(s)
Luminiscencia , Nanopartículas , Calcio , Portadores de Fármacos , Nanopartículas/química , Fosfatos , Zinc , Compuestos de Zinc
19.
World J Surg Oncol ; 20(1): 256, 2022 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-35948931

RESUMEN

Gastrointestinal melanoma is usually metastatic in origin, and primary melanoma within the gastrointestinal tract is rarely reported. Colon is considered to be an extremely uncommon site for primary melanomas. Herein, we report the first case of a large primary melanoma within the transverse colon with gastric involvement. CT scan found a mass within the colon, which seemed to connect to the gastric antrum. Esophagogastroscopy showed an ulcerated lesion in the greater curvature of the stomach. Subsequent colonoscopy identified a large ulcerated lesion rendering significant stenosis of the transverse colon. Biopsy following colonoscopy indicated a diagnosis of colonic melanoma based on pathological findings, which identified submucosal malignant melanoma cells with epithelioid and spindle features. Immunohistochemical stains were positive for S-100, HMB-45, Vimentin, and Melan-A. A series of clinical and imaging examinations revealed no suspicious primary cutaneous or ocular lesions. The diagnosis of primary colonic melanoma was considered. A radical transverse colectomy with subtotal gastrectomy were conducted subsequently. Definite diagnosis of primary colonic melanoma can be established after ruling out the possibility of being a metastasis from other more common primary sites. Primary colonic melanomas are a challenge to diagnose and often need a multidisciplinary treatment approach, including surgery, BRAF-targeted therapy, and immunotherapy.


Asunto(s)
Neoplasias del Colon , Melanoma , Colectomía , Neoplasias del Colon/patología , Humanos , Melanoma/cirugía , Proteínas S100
20.
Ecotoxicol Environ Saf ; 231: 113215, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35065506

RESUMEN

Thyroid hormone homeostasis is essential for normal brain development in fetuses and infants. Exposure to endocrine-disrupting chemicals (EDCs) during pregnancy is associated with compromised maternal thyroid homeostasis, and thus may lead to adverse neurodevelopmental outcomes in newborns. However, evidence regarding the association of prenatal EDC exposure and thyroid hormones in newborns is controversial. Therefore, a meta-analysis to elucidate the relationship between maternal exposure to EDCs and neonatal THs was performed. A systematic search of PubMed, EMBASE, and the Cochrane Library (CENTRAL) for relevant published studies that provided quantitative data on the association between prenatal EDC exposure and neonatal thyroid hormones was conducted in August 2021. To calculate the overall estimates, we pooled the adjusted ß regression coefficients with 95% confidence intervals (CIs) from each study by the inverse variance method. The pooling results indicated that prenatal EDC exposure had no significant influence on neonatal TSH, TT3, FT3, TT4 or FT4 level in the global assessment. However, in the specific exposure and outcome assessment, we found that prenatal exposure to organochlorine (ß coefficient, -0.022; 95% CI, -0.04 to -0.003) and PFAS (ß coefficient, -0.017; 95% CI, -0.033 to 0) was negatively associated with neonatal TT4 level. In conclusion, prenatal exposure to organochlorine and PFAS may be associated with lower neonatal TT4 level.


Asunto(s)
Disruptores Endocrinos , Efectos Tardíos de la Exposición Prenatal , Disruptores Endocrinos/toxicidad , Femenino , Humanos , Lactante , Recién Nacido , Exposición Materna/efectos adversos , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Glándula Tiroides , Hormonas Tiroideas
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