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1.
Bioorg Chem ; 145: 107186, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38387394

RESUMEN

Heterotypic ubiquitin (Ub) chains have emerged as fundamental components in a wide range of cellular processes. The integrative identification of Ub-interacting proteins (readers) and Ub-modifying enzymes (writers and erasers) that selectively recognize and regulate heterotypic ubiquitination may provide crucial insights into these processes. In this study, we employed the bifunctional molecule-assisted (CAET) strategy to develop a type of disulfide bond-activated heterotypic Ub reagents, which allowed to enrich heterotypic Ub-interacting proteins and modifying enzymes simultaneously. The sequential release of readers which are non-covalently bound and writers or erasers which are covalently conjugated by using urea and reductant, respectively, combined with label-free quantitative (LFQ) MS indicated that these heterotypic Ub reagents would facilitate future investigations into functional roles played by heterotypic Ub chains.


Asunto(s)
Proteínas , Ubiquitina , Ubiquitina/metabolismo , Indicadores y Reactivos , Ubiquitinación , Proteínas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
2.
Int Heart J ; 65(4): 730-737, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39085112

RESUMEN

Sodium tanshinone IIA sulfonate (STS), which is extracted from a Chinese medicinal herb, possesses many pharmacologic functions, such as coronary dilation, anti-inflammatory properties, and antiapoptotic and antioxidant effects. It remains unknown whether STS can protect cardiomyocytes injured after radiation therapy. An in vitro Sprague-Dawley (SD) rat neonatal cardiomyocyte system was established. Primary cardiomyocytes (PCMs) from neonatal SD rats were isolated under sterile conditions. PCM cells were divided into a control group (0 Gy/hour) and 5 experimental radiation therapy groups (0.25 Gy/hour, 0.5 Gy/hour, 1 Gy/hour, 2 Gy/hour, and 4 Gy/hour). Cell viability, the content of malondialdehyde (MDA), the lactate dehydrogenase (LDH) leakage rate, and superoxide dismutase (SOD) and glutathione (GSH) activities were recorded separately in each group after 7 days of culture. Western blot was used to detect the levels of p38, caspase-3 protein, and X protein (BAX) associated with B-cell lymphoma 2 (Bcl-2) in PCMs. X-rays inhibited cell growth, decreased cell viability, and induced an oxidative stress response in PCMs. STS and SB203580 (the inhibitor of P38 mitogen-activated protein kinase pathway) alleviated X-ray-induced damage to PCMs. An enzyme-linked immunosorbent assay showed that X-rays increased the cTnT level. STS and SB203580 ameliorated the X-ray-induced increase in cTnT leakage. X-rays enhanced the expression of p38/p-p38 and caspase-3 while reducing the expression of Bcl-2/BAX in PCMs, as demonstrated by western blotting. STS and SB203580 mitigated the changes in protein expression triggered by X-ray radiation. In conclusions, STS was shown to exert significant cardioprotective, anti-inflammatory, and antioxidant effects in PCMs by inhibiting the p38 mitogen-activated protein kinase pathway.


Asunto(s)
Miocitos Cardíacos , Fenantrenos , Ratas Sprague-Dawley , Proteínas Quinasas p38 Activadas por Mitógenos , Animales , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/efectos de la radiación , Ratas , Fenantrenos/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Células Cultivadas , Animales Recién Nacidos , Supervivencia Celular/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Apoptosis/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Antioxidantes/farmacología
3.
Angew Chem Int Ed Engl ; : e202408673, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38981860

RESUMEN

Biomaterials such as spider silk and mussel byssi are fabricated by the dynamic manipulation of intra- and intermolecular biopolymer interactions. Organisms modulate solution parameters, such as pH and ion co-solute concentration, to effect these processes. These biofabrication schemes provide a conceptual framework to develop new dynamic and responsive abiotic soft material systems. Towards these ends, the chemical diversity of readily available ionic compounds offers a broad palette to manipulate the physicochemical properties of polyelectrolytes via ion-specific interactions. In this study, we show for the first time that the ion-specific interactions of biomimetic polyelectrolytes engenders a variety of phase separation behaviors, creating dynamic, thermal and ion responsive soft matter. that exhibits a spectrum of physical properties, spanning viscous fluids, to viscoelastic and viscoplastic solids. These ion dependent characteristics are further rendered general by the merger of lysine and phenylalanine into a single, amphiphilic vinyl monomer. The unprecedented breadth, precision, and dynamicity in the reported ion dependent phase behaviors thus introduce a broad array of opportunities for the future development of responsive soft matter, properties that are poised to drive developments in critical areas such as chemical sensing, soft robotics, and additive manufacturing.

4.
Am J Transl Res ; 16(5): 1859-1879, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38883361

RESUMEN

OBJECTIVE: High doses of radiation, while effective at destroying tumor tissues, also result in radiation dermatitis (RD) at irradiated sites, which is one of the most common complications in cancer radiotherapy. Currently, no standardized protocols for the prevention and treatment of RD have been established in clinical practices, and severe RD can compromise treatment efficacy and reduce patients' quality of life. This systematic review and network meta-analysis (NMA) aims to compare the effectiveness of various interventions in preventing RD in patients. METHODS: As of June 2023, four databases, including PubMed, Embase, Web of Science, and the Cochrane Library, were searched, with a total of 19 interventions obtained for comparative analysis of their effectiveness in preventing RD. The Cochrane risk-of-bias tool was employed to screen literature, extract data, and appraise the quality of the studies by two researchers. Bayesian network meta-analysis (NMA) was conducted utilizing StataSE 15 and R 4.2.3. RESULTS: A total of 33 studies involving 4307 patients were included in this analysis. From the 33 studies, 19 interventions, encompassing Barrier Films and Dressings (BFD), Boron_Gel, Best supportive care, Corticosteroids_cream, Doxepin_cream, Eau Thermale Avèn_gel, Epidermal Growth Factor_cream, Hyaluronan_cream, Medicinal_Plants, Mineral_Oil, Olive oil and calcium hydroxide (OOCH), Photobiomodulation therapy, Recove_cream, Silicone_gel, Silver sulfadiazine (SSD), Timolol_Gel, Trolamine, VitD_Gel, and VitE_Gel, were retrieved and compared. The NMA results indicated that Hyaluronan_cream (SUCRA: 94.9%) was highly effective in preventing Grade 0/1 RD. Meanwhile, OOCH (SUCRA: 95.7%) demonstrated the most prominent effect in preventing ≥ Grade 2 RD. CONCLUSION: The study reveals that Hyaluronan_cream and OOCH are two promising treatments for the prevention of RD in patients undergoing radiotherapy. Future research might focus on validating the efficacy of these two therapies with large sample sizes and on identifying an optimal intervention strategy.

5.
Adv Radiat Oncol ; 9(7): 101503, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38883996

RESUMEN

Purpose: Although active spot scanning irradiation technique is theoretically superior to passive-scattered broad beam irradiation with respect to normal tissue sparing, corroborations of the clinical benefit of carbon-ion spot scanning have remained scarce. This study aims to investigate the feasibility and clinical implementation of an active spot scanning beam calculation algorithm in a homemade carbon-ion treatment planning system by comparing it with a conventional passive uniform scanning technique. Methods and Materials: Carbon-ion plans were initially formulated using spot/uniform scanning methods in 22 participants enrolled in a prospective observational clinical trial. Subsequently, 2 additional plans were designed, resulting in 3 carbon-ion plans for each participant: uniform and spot scanning with miniridge filters of 2 mm and 4 mm, respectively. Results: The findings revealed no significant differences in dose homogeneity; however, significant differences in dose conformity were found between the active and passive scanning plans. For dose drop-off outside the target volume, the average gradient index values were 1.94 (95% CI, 1.79%-2.09%), 1.87 (95% CI, 1.73%-2.01%), and 3.20 (95% CI, 2.80%-3.61%) for the miniridge filters of 2 mm and 4 mm, and uniform scanning plans, respectively. The pretreatment tumor volume was 124.7 cm3 (range, 54.2-234 cm3), and the average shrinkage observed was 38.4% (95% CI, 17.6%-59.4%). Seven participants experienced grade 1 acute toxicity, and 4 experienced grade 2 acute toxicity. However, none of the patients developed grade 3 acute toxicity. Conclusions: Increasing evidence suggests that potential clinical advantages of spot scanning delivery underlie its technical characteristics. As one among the few institutions currently using carbon-ion radiation therapy, the investigation also provides promising safety and efficacy outcomes from the initial groups of treated participants, thereby contributing to the established clinical evidence supporting the effectiveness and superiority of carbon-ion therapy.

6.
Nat Commun ; 15(1): 1266, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38341401

RESUMEN

Ubiquitination, catalyzed usually by a three-enzyme cascade (E1, E2, E3), regulates various eukaryotic cellular processes. E3 ligases are the most critical components of this catalytic cascade, determining both substrate specificity and polyubiquitination linkage specificity. Here, we reveal the mechanism of a naturally occurring E3-independent ubiquitination reaction of a unique human E2 enzyme UBE2E1 by solving the structure of UBE2E1 in complex with substrate SETDB1-derived peptide. Guided by this peptide sequence-dependent ubiquitination mechanism, we developed an E3-free enzymatic strategy SUE1 (sequence-dependent ubiquitination using UBE2E1) to efficiently generate ubiquitinated proteins with customized ubiquitinated sites, ubiquitin chain linkages and lengths. Notably, this strategy can also be used to generate site-specific branched ubiquitin chains or even NEDD8-modified proteins. Our work not only deepens the understanding of how an E3-free substrate ubiquitination reaction occurs in human cells, but also provides a practical approach for obtaining ubiquitinated proteins to dissect the biochemical functions of ubiquitination.


Asunto(s)
Enzimas Ubiquitina-Conjugadoras , Ubiquitina-Proteína Ligasas , Humanos , Péptidos/metabolismo , Ubiquitina/metabolismo , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Ubiquitinadas/metabolismo , Ubiquitinación , Ingeniería de Proteínas
7.
Nutrients ; 16(8)2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38674845

RESUMEN

Nitrate (NO3-) obtained from the diet is converted to nitrite (NO2-) and subsequently to nitric oxide (NO) within the body. Previously, we showed that porcine eye components contain substantial amounts of nitrate and nitrite that are similar to those in blood. Notably, cornea and sclera exhibited the capability to reduce nitrate to nitrite. To gain deeper insights into nitrate metabolism in porcine eyes, our current study involved feeding pigs either NaCl or Na15NO3 and assessing the levels of total and 15N-labeled NO3-/NO2- in various ocular tissues. Three hours after Na15NO3 ingestion, a marked increase in 15NO3- and 15NO2- was observed in all parts of the eye; in particular, the aqueous and vitreous humor showed a high 15NO3- enrichment (77.5 and 74.5%, respectively), similar to that of plasma (77.1%) and showed an even higher 15NO2- enrichment (39.9 and 35.3%, respectively) than that of plasma (19.8%). The total amounts of NO3- and NO2- exhibited patterns consistent with those observed in 15N analysis. Next, to investigate whether nitrate or nitrite accumulate proportionally after multiple nitrate treatments, we measured nitrate and nitrite contents after supplementing pigs with Na15NO3 for five consecutive days. In both 15N-labeled and total nitrate and nitrite analysis, we did not observe further accumulation of these ions after multiple treatments, compared to a single treatment. These findings suggest that dietary nitrate supplementation exerts a significant influence on nitrate and nitrite levels and potentially NO levels in the eye and opens up the possibility for the therapeutic use of dietary nitrate/nitrite to enhance or restore NO levels in ocular tissues.


Asunto(s)
Suplementos Dietéticos , Nitratos , Nitritos , Animales , Nitratos/metabolismo , Porcinos , Nitritos/metabolismo , Ojo/metabolismo , Isótopos de Nitrógeno , Córnea/metabolismo , Dieta , Humor Acuoso/metabolismo , Cuerpo Vítreo/metabolismo , Óxido Nítrico/metabolismo , Alimentación Animal/análisis
8.
Nat Commun ; 15(1): 5193, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38890366

RESUMEN

Multichannel meta-imaging, inspired by the parallel-processing capability of neuromorphic computing, offers considerable advancements in resolution enhancement and edge discrimination in imaging systems, extending even into the mid- to far-infrared spectrum. Currently typical multichannel infrared imaging systems consist of separating optical gratings or merging multi-cameras, which require complex circuit design and heavy power consumption, hindering the implementation of advanced human-eye-like imagers. Here, we present printable graphene plasmonic photodetector arrays driven by a ferroelectric superdomain for multichannel meta-infrared imaging with enhanced edge discrimination. The fabricated photodetectors exhibited multiple spectral responses with zero-bias operation by directly rescaling the ferroelectric superdomain instead of reconstructing the separated gratings. We also demonstrated enhanced and faster shape classification (98.1%) and edge detection (98.2%) using our multichannel infrared images compared with single-channel detectors. Our proof-of-concept photodetector arrays simplify multichannel infrared imaging systems and offer potential solutions in efficient edge detection in human-brain-type machine vision.

9.
Adv Mater ; : e2402971, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39011789

RESUMEN

For multicenter-catalyzed reactions, it is important to accurately construct heterogeneous catalysts containing multiple active centers with high activity and low cost, which is more challenging compared to homogeneous catalysts because of the low activity and spatial confinement of active centers in the loaded state. Herein, a convenient protein confinement strategy is reported to locate Pd and Cu single atoms in crowding state on carbon coated alumina for promoting Sonogashira reaction, the most powerful method for constructing the acetylenic moiety in molecules. The single-atomic Pd and Cu centers take advantage in not only the maximized atomic utilization for low cost, but also the much-enhanced performance by facilitating the activation of aryl halides and alkynes. Their locally crowded dispersion brings them closer to each other, which facilitates the transmetallation process of acetylide intermediates between them. Thus, the Sonogashira reaction is drove smoothly by the obtained catalyst with a turnover frequency value of 313 h-1, much more efficiently than that by commercial Pd/C and CuI catalyst, conventional Pd and Cu nanocatalysts, and mixed Pd and Cu single-atom catalyst. The obtained catalyst also exhibits the outstanding durability in the recycling test.

10.
Am J Clin Nutr ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39111550

RESUMEN

BACKGROUND: Low-calorie sweetener (LCS) consumption is prevalent among lactating females, yet infants' exposure to LCS in human milk is not well-characterized. OBJECTIVES: Conduct a pharmacokinetic study of sucralose and acesulfame-potassium (ace-K) in mothers' milk and plasma over 72 h and in infants' plasma. METHODS: Following baseline blood and milk collection, mothers (n = 40) consumed 20 oz of diet cranberry juice containing sucralose and ace-K. Blood samples were collected from the mother 0.5, 1, 1.5, 2, 3, 4, 6, 8, 12, 24, 48, and 72 h after beverage ingestion, and milk was expressed at 1, 2, 3, 4, 6, 8, 12, and 24 h postingestion. One blood sample was collected from each infant, the timing of which was determined using pharmacokinetics model-based simulation. Concentration-time profiles of LCS from the mother's plasma and milk were analyzed using noncompartmental methods. RESULTS: Ace-K rapidly entered human milk with the largest observed concentration of 373.0 (coefficient of variation 69%) ng/mL first detected 4 h following diet beverage ingestion. Sucralose appeared in human milk 1-2 h after diet beverage ingestion with the largest observed concentration of 7.2 (coefficient of variation 63%) ng/mL first detected 7 h postingestion. The mean 24-h milk to plasma ratio of ace-K was 1.75 [standard deviation (SD) 1.37] with a mean relative infant dose of 1.59% (SD 1.72%). Ace-K was detected in all infants' plasma with an average concentration of 9.2 (SD% 14.8) ng/mL ∼6 h after maternal beverage ingestion. The mean 24-h milk to plasma ratio of sucralose was 0.15 (SD 0.06) with a mean relative infant dose of 0.04% (SD 0.02%). Sucralose was detected in only 15 infants' plasma, and the average concentration was 5.0 (SD% 7.1) ng/mL, ∼5 h after diet beverage ingestion. CONCLUSIONS: Ace-K rapidly transfers from human milk into infants' circulation whereas sucralose was detected at much lower concentrations and in some but not all infants. Future research should investigate the effects of early-life sucralose and ace-K exposure via human milk on infants' health. This trial was registered at clinicaltrials.gov as NCT05379270.

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