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1.
J Agric Food Chem ; 72(43): 23957-23968, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39425699

RESUMEN

Bergenia purpurascens, renowned for its antibacterial and antioxidant properties, remains relatively unexplored in its impact on melanogenesis. This study delves into the antimelanogenic potential of the ethanol extract derived from B. purpurascens (BPE). Our investigations reveal the robust antioxidant capabilities of the BPE, along with its effective inhibition of mushroom tyrosinase activity. Remarkably, these effects were significantly stronger than those observed with arbutin, the positive control. In vitro assays demonstrate the BPE's efficacy in reducing the melanin content and tyrosinase activity in α-MSH-stimulated B16F10 cells. Immunofluorescence and qPCR analyses further reveal the BPE's ability to inhibit MITF-mediated gene expression levels associated with melanogenesis, including Trp-1, Trp-2, and tyrosinase. These findings suggest that the extract operates through dual mechanisms, suppressing both tyrosinase activity and key transcription factor-mediated downstream signaling. Utilizing UPLC-MS/MS analysis, we identified six key compounds implicated in tyrosinase activity inhibition and melanogenesis suppression. Docking simulations confirm moderate binding affinities between these compounds and tyrosinase. This study highlights the potential of B. purpurascens as a novel natural agent for depigmentation in medicinal and cosmetic applications, elucidating its dual mechanism of action in melanogenesis inhibition.


Asunto(s)
Melaninas , Monofenol Monooxigenasa , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Monofenol Monooxigenasa/genética , Animales , Melaninas/metabolismo , Ratones , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Extractos Vegetales/farmacología , Extractos Vegetales/química , Línea Celular Tumoral , Agaricales/química , Simulación del Acoplamiento Molecular , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Factor de Transcripción Asociado a Microftalmía/genética , Factor de Transcripción Asociado a Microftalmía/metabolismo
2.
Child Abuse Negl ; 157: 107082, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39396396

RESUMEN

BACKGROUND: Although existing research has reported the impacts of COVID-19 on child abuse and neglect (CAN), little attention was paid to the relationship between spatial patterns in the trends of COVID-19 cases and their effects on the prevalence of CAN cases. OBJECTIVE: This study examined the associations between trends of confirmed cases of COVID-19 and child removal due to physical abuse and neglect at the county level in the U.S while taking the social vulnerability into account. PARTICIPANTS AND SETTING: This study utilized three secondary data sets nationally collected. METHODS: Spatial-temporal cluster analysis was used to classify and assign trends in confirmed cases of COVID-19 into their distinctive clusters. These spatial-temporal clusters were then used as independent variables in the negative binomial regression (NBR) models. RESULTS: Average cases of physical abuse and neglect increased as the growth rates of confirmed cases of COVID-19 were accelerated except for the counties assigned to the cluster characterized by moderately low increase and very high increases. NBR found social vulnerability measures have no effects on child removal due to physical abuse and neglect after controlling spatial-temporal clusters of the confirmed cases of COVID-19. CONCLUSIONS: Our study indicates that concentration of disaster has certain effects on child maltreatment. This suggests that child welfare pay special attention to the areas that undergo steep increases in confirmed cases under public health crises.


Asunto(s)
COVID-19 , Maltrato a los Niños , Vulnerabilidad Social , Análisis Espacio-Temporal , Humanos , Maltrato a los Niños/estadística & datos numéricos , COVID-19/epidemiología , Estados Unidos/epidemiología , Niño , Análisis por Conglomerados , Preescolar , Análisis de Regresión , Femenino , Masculino , SARS-CoV-2 , Prevalencia
3.
J Org Chem ; 89(20): 14968-14980, 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39364928

RESUMEN

A copper-catalyzed [3 + 2] annulation of O-acyl oximes with 2-electron-withdrawing group substituted p-hydroquinones for the efficient synthesis of polysubstituted 5-hydroxyindoles is developed. Further intramolecular cyclization leads to the concise and rapid construction of several kinds of 3,4- and 4,5-fused polycyclic indoles.

4.
Blood Adv ; 8(21): 5674-5682, 2024 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-39226464

RESUMEN

ABSTRACT: The multicenter, prospective phase 2 Australasian Leukaemia & Lymphoma Group NHL29 trial was conducted to assess the addition of ibrutinib to R-mini-CHOP (dose attenuated R-CHOP; rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) in patients aged ≥75 years with newly diagnosed diffuse large B-cell lymphoma (DLBCL). Treatment consisted of six 21-day cycles of ibrutinib-R-mini-CHOP followed by two 21-day cycles of R-ibrutinib. Coprimary end points were deliverability and 2-year overall survival (OS). The median average relative total dose and average relative dose intensity for the entire regimen were both 97% (interquartile range, 82-100 and 88-100, respectively). With a median follow-up of 35.5 months, the 2-year OS was 68% (95% confidence interval [CI], 55.6-77.4) with a 2-year progression-free survival (PFS) of 60.0% (95% CI, 47.7-70.3). Median OS and PFS were 72 months (95% CI, 35 to not reached) and 40 months (95% CI, 20.4 to not reached), respectively. The overall response rate was 76% (61/79) of patients, with a complete response rate of 71% (56/79). Deaths occurred in 34 of 79 patients (43%), including 17 from progressive disease and 5 treatment related. Overall, 67% patients experienced at least 1 serious adverse event. Most common adverse events were infections and diarrhea (the majority grade 1-2). In both health-related quality of life measures, there was an improvement in functional and symptom scales, median health state classification score, and median visual analogue scale in responders over time. In conclusion, this study showed that the addition of ibrutinib to R-mini-CHOP was both deliverable and efficacious in elderly DLBCL patients.


Asunto(s)
Adenina , Protocolos de Quimioterapia Combinada Antineoplásica , Ciclofosfamida , Doxorrubicina , Linfoma de Células B Grandes Difuso , Piperidinas , Prednisona , Rituximab , Vincristina , Humanos , Rituximab/uso terapéutico , Rituximab/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Anciano , Piperidinas/uso terapéutico , Piperidinas/administración & dosificación , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/mortalidad , Adenina/análogos & derivados , Adenina/uso terapéutico , Adenina/administración & dosificación , Vincristina/uso terapéutico , Vincristina/administración & dosificación , Ciclofosfamida/uso terapéutico , Ciclofosfamida/administración & dosificación , Femenino , Masculino , Anciano de 80 o más Años , Doxorrubicina/uso terapéutico , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Prednisona/uso terapéutico , Prednisona/administración & dosificación , Resultado del Tratamiento , Pirimidinas/uso terapéutico , Pirimidinas/administración & dosificación , Pirazoles/uso terapéutico , Pirazoles/administración & dosificación
5.
Front Oncol ; 14: 1396655, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39301554

RESUMEN

This is the first report of NUP98::LEDGF positive malignant hematological tumor expressing T cell and myeloid lineage antigens. Patients carrying this fusion gene have a high relapse rate and a poor prognosis, allo-HSCT may be an option to cure this disease. This patient underwent allo-HSCT, a relapse occurred three months post-transplantation. Subsequent screening at our hospital confirmed the presence of the NUP98::LEDGF fusion gene, salvage therapy was administered, followed by a successful second allo-HSCT. Furthermore, we included eight previously reported cases from the literature for analysis and discuss.

6.
Mol Cell Probes ; 77: 101981, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39197503

RESUMEN

The clinical treatment of hepatocellular carcinoma (HCC) is still a heavy burden worldwide. Intracellular microRNAs (miRNAs) commonly express abnormally in cancers, thus they are potential therapeutic targets for cancer treatment. miR-21 is upregulated in HCC whereas miR-122 is enriched in normal hepatocyte but downregulated in HCC. In our study, we first generated a reporter genetic switch compromising of miR-21 and miR-122 sponges as sensor, green fluorescent protein (GFP) as reporter gene and L7Ae:K-turn as regulatory element. The reporter expression was turned up in miR-21 enriched environment while turned down in miR-122 enriched environment, indicating that the reporter switch is able to respond distinctly to different miRNA environment. Furthermore, an AAT promoter, which is hepatocyte-specific, is applied to increase the specificity to hepatocyte. A killing switch with AAT promoter and an apoptosis-inducing element, Bax, in addition to miR-21 and miR-122 significantly inhibited cell viability in Huh-7 by 70 % and in HepG2 by 60 %. By contrast, cell viability was not affected in five non-HCC cells. Thus, we provide a novel feasible strategy to improve the safety of miRNA-based therapeutic agent to cancer.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Regiones Promotoras Genéticas , MicroARNs/genética , MicroARNs/metabolismo , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Regiones Promotoras Genéticas/genética , Genes Reporteros , Células Hep G2 , Línea Celular Tumoral , Supervivencia Celular/genética , Regulación Neoplásica de la Expresión Génica , Proteínas Fluorescentes Verdes/metabolismo , Proteínas Fluorescentes Verdes/genética , Especificidad de Órganos/genética
7.
Adv Mater ; 36(39): e2407822, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39104291

RESUMEN

Spin-crossover (SCO) ferroelectrics with dual-function switches have attracted great attention for significant magnetoelectric application prospects. However, the multiferroic crystals with SCO features have rarely been reported. Herein, a molecular multiferroic Fe(II) crystalline complex [FeII(C8-F-pbh)2] (1-F, C8-F-pbh = (1Z,N'E)-3-F-4-(octyloxy)-N'-(pyridin-2-ylmethylene)-benzo-hydrazonate) showing the coexistence of ferroelectricity, ferroelasticity, and SCO behavior is presented for the first time. By H/F substitution, the low phase transition temperature (270 K) of the non-fluorinated parent compound is significantly increased to 318 K in 1-F, which exhibits a spatial symmetry breaking 222F2 type ferroelectric phase transition with clear room-temperature ferroelectricity. Besides, 1-F also displays a spin transition between high- and low-spin states, accompanied by the d-orbital breaking within the t2g 4eg 2 and t2g 6eg° configuration change of octahedrally coordinated FeII center. Moreover, the 222F2 type ferroelectric phase transition is also a ferroelastic one, verified by the ferroelectric domains reversal and the evolution of ferroelastic domains. To the knowledge, 1-F is the first multiferroic SCO molecular crystal. This unprecedented finding sheds light on the exploration of molecular multistability materials for future smart devices.

8.
Artículo en Inglés | MEDLINE | ID: mdl-39208603

RESUMEN

Magnolia bark is a traditional Chinese medicine used for hypoglycaemia. With the widespread use of Magnolia bark, its resources are facing a serious shortage. To address this issue, a strategy based on high-coverage mass spectrometry (HCMS) and multidimensional chemical-biological analysis (MCBA) was proposed for the comprehensive exploration of Magnolia officinalis which is the main source of Magnolia bark. The strategy is divided into three main steps. In the first step, the stem bark, stem xylem, root bark, root xylem, leaf and rootlet of Magnolia officinalis were comprehensively analyzed using high-coverage mass spectrometry. In the second step, multivariate statistical analysis was used to explore the heterogeneity of the six parts and detect differential chemical components. In the third step, a combination of experimental screening and molecular docking was used to explore α-glucosidase inhibitors from Magnolia officinalis. Multidimensional chemical-biological analysis (MCBA) of Magnolia officinalis was achieved by combining the last two steps. Finally, a total of 103 compounds were identified from the whole plant of Magnolia officinalis. Differential components of stem bark, stem xylem, leaf, root bark, root xylem and rootlet were systematically revealed. A pair of positional isomers, namely magnolol and honokiol, were found to be α-glucosidase inhibitors. The activity of their combination is superior to that of each single compound, indicating that magnolol and honokiol are in a synergistic relationship. This strategy contributes to comprehensive exploitation of functional plants and effective alleviation of resource shortage. This study also provides a research paradigm for other similar traditional Chinese medicinal plants.


Asunto(s)
Magnolia , Espectrometría de Masas , Magnolia/química , Espectrometría de Masas/métodos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Simulación del Acoplamiento Molecular , Plantas Medicinales/química , Inhibidores de Glicósido Hidrolasas/análisis , Inhibidores de Glicósido Hidrolasas/química
9.
Indian J Otolaryngol Head Neck Surg ; 76(4): 3018-3030, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39130301

RESUMEN

Nasal surgeries (e.g.: rhinoplasties, septoplasties) and sinus surgeries (e.g.: Functional Endoscopic Sinus Surgeries) are common procedures in Otorhinolaryngology. Tranexamic acid (TXA), an antifibrinolytic drug, has been increasingly utilized to reduce hemorrhage recently. While close in proximity anatomically, the bleeding nature of sinus and nasal surgeries may differ. We present the first meta-analysis that has reviewed both nasal and sinus surgery collectively and compares the two. Pubmed, Embase, Cochrane Library and WoS were searched until April 2023. Outcomes of interest include Boezart Scoring, clotting time, postoperative complications and surgical field quality. 27 Studies were assessed, of which 25 studies were evaluated quantitatively. Of the 27 studies, 15 studies involved Sinus surgery while 12 involved Nasal surgery. The use of tranexamic acid was notably beneficial in the evaluation of blood loss, reduction of operating time, surgical field quality and surgeon satisfaction. TXA has proven to be efficacious in both nasal and sinus surgeries to varying degrees. TXA has more effects in sinus surgeries compared to nasal surgeries in objective markers such as reducing blood loss and operating time, but the converse occurs for subjective markers such as surgeon satisfaction scores. Supplementary Information: The online version contains supplementary material available at 10.1007/s12070-024-04579-x.

10.
J Agric Food Chem ; 72(31): 17328-17342, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39045647

RESUMEN

Zanthoxyli radix is a popular tea among the elderly, and it is believed to have a positive effect on Alzheimer's disease. In this study, a highly effective three-step strategy was proposed for comprehensive analysis of the active components and biological functions of Zanthoxylum nitidum (ZN), including high-resolution LC-Q-TOF mass spectrometry (HRMS), multivariate statistical analysis for heterogeneity (MSAH), and experimental and virtual screening for bioactivity analysis (EVBA). A total of 117 compounds were identified from the root, stem, and leaf of ZN through HRMS. Bioactivity assays showed that the order of acetylcholinesterase (AChE) inhibitory activity from strong to weak was root > stem > leaf. Nitidine, chelerythrine, and sanguinarine were found to be the main differential components of root, stem, and leaf by OPLS-DA. The IC50 values of the three compounds are 0.81 ± 0.02, 0.14 ± 0.01, and 0.48 ± 0.01 µM respectively, indicating that they are potent and high-quality AChE inhibitors. Molecular docking showed that pi-pi T-shaped interactions and pi-lone pairs played important roles in AChE inhibition. This study not only explains the biological function of Zanthoxyli radix in alleviating Alzheimer's disease to some extent, but also lays the foundation for the development of stem and leaf of ZN.


Asunto(s)
Acetilcolinesterasa , Inhibidores de la Colinesterasa , Espectrometría de Masas , Simulación del Acoplamiento Molecular , Hojas de la Planta , Zanthoxylum , Zanthoxylum/química , Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Acetilcolinesterasa/química , Acetilcolinesterasa/metabolismo , Hojas de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Raíces de Plantas/química , Tallos de la Planta/química , Cromatografía Líquida de Alta Presión , Humanos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología
11.
Adv Mater ; 36(35): e2405981, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38970528

RESUMEN

Ferroelectric materials, traditionally comprising inorganic ceramics and polymers, are commonly used in medical implantable devices. However, their nondegradable nature often necessitates secondary surgeries for removal. In contrast, ferroelectric molecular crystals have the advantages of easy solution processing, lightweight, and good biocompatibility, which are promising candidates for transient (short-term) implantable devices. Despite these benefits, the discovered biodegradable ferroelectric materials remain limited due to the absence of efficient design strategies. Here, inspired by the polar structure of polyvinylidene fluoride (PVDF), a ferroelectric molecular crystal 1H,1H,9H,9H-perfluoro-1,9-nonanediol (PFND), which undergoes a cubic-to-monoclinic ferroelectric plastic phase transition at 339 K, is discovered. This transition is facilitated by a 2D hydrogen bond network formed through O-H···O interactions among the oriented PFND molecules, which is crucial for the manifestation of ferroelectric properties. In this sense, by reducing the number of -CF2- groups from ≈5 000 in PVDF to seven in PFND, it is demonstrated that this ferroelectric compound only needs simple solution processing while maintaining excellent biosafety, biocompatibility, and biodegradability. This work illuminates the path toward the development of new biodegradable ferroelectric molecular crystals, offering promising avenues for biomedical applications.

12.
Phytochem Anal ; 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39037036

RESUMEN

INTRODUCTION: Marsdeniae tenacissimae Caulis (MTC), a popular traditional Chinese medicine, has been widely used in the treatment of tumor diseases. Paederiae scandens Caulis (PSC), which is similar in appearance to MTC, is a common counterfeit product. It is difficult for traditional methods to effectively distinguish between MTC and PSC. Therefore, there is an urgent need for a rapid and accurate method to identify MTC and PSC. OBJECTIVES: The aim is to distinguish between MTC and PSC by analyzing the differences in nonvolatile organic compounds (NVOCs), taste, odor, and volatile organic compounds (VOCs). METHODS: Liquid chromatography-mass spectrometry (LC-MS) was utilized to analyze the NVOCs of MTC and PSC. Electronic tongue (E-tongue) and electronic nose (E-nose) were used to analyze their taste and odor respectively. Gas chromatography-ion mobility spectrometry (GC-IMS) was applied to analyze VOCs. Finally, multivariate statistical analyses were conducted to further investigate the differences between MTC and PSC, including principal component analysis, orthogonal partial least squares discriminant analysis, discriminant factor analysis, and soft independent modeling of class analysis. RESULTS: The results of this study indicate that the integrated strategy of LC-MS, E-tongue, E-nose, GC-IMS, and multivariate statistical analysis can be effectively applied to distinguish between MTC and PSC. Using LC-MS, 25 NVOCs were identified in MTC, while 18 NVOCs were identified in PSC. The major compounds in MTC are steroids, while the major compounds in PSC are iridoid glycosides. Similarly, the distinct taste difference between MTC and PSC was precisely revealed by the E-tongue. Specifically, the pronounced bitterness in PSC was proven to stem from iridoid glycosides, whereas the bitterness evident in MTC was intimately tied to steroids. The E-nose detected eight odor components in MTC and six in PSC, respectively. The subsequent statistical analysis uncovered notable differences in their odor profiles. GC-IMS provided a visual representation of the differences in VOCs between MTC and PSC. The results indicated a relatively high relative content of 82 VOCs in MTC, contrasted with 32 VOCs exhibiting a similarly high relative content in PSC. CONCLUSION: In this study, for the first time, the combined use of LC-MS, E-tongue, E-nose, GC-IMS, and multivariate statistical analysis has proven to be an effective method for distinguishing between MTC and PSC from multiple perspectives. This approach provides a valuable reference for the identification of other visually similar traditional Chinese medicines.

13.
Front Bioeng Biotechnol ; 12: 1395540, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39055341

RESUMEN

Acetogenic bacteria (acetogens) are a class of microorganisms with conserved Wood-Ljungdahl pathway that can utilize CO and CO2/H2 as carbon source for autotrophic growth and convert these substrates to acetate and ethanol. Acetogens have great potential for the sustainable production of biofuels and bulk biochemicals using C1 gases (CO and CO2) from industrial syngas and waste gases, which play an important role in achieving carbon neutrality. In recent years, with the development and improvement of gene editing methods, the metabolic engineering of acetogens is making rapid progress. With introduction of heterogeneous metabolic pathways, acetogens can improve the production capacity of native products or obtain the ability to synthesize non-native products. This paper reviews the recent application of metabolic engineering in acetogens. In addition, the challenges of metabolic engineering in acetogens are indicated, and strategies to address these challenges are also discussed.

14.
BMC Ophthalmol ; 24(1): 270, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38914965

RESUMEN

BACKGROUND: This study aimed to explore differences in vitreous humour metabolites and metabolic pathways between patients with and without diabetic retinopathy (DR) and identify potential metabolite biomarkers. METHODS: Clinical data and vitreous fluid samples were collected from 125 patients (40 without diabetes, 85 with DR). The metabolite profiles of the vitreous fluid samples were analysed using ultra-high performance liquid chromatography, Q-Exactive mass spectrometry, and multivariate statistical analysis. A machine learning model based on Least Absolute Shrinkage and Selection Operator Regularized logistic regression was used to build a risk scoring model based on selected metabolite levels. Candidate metabolites were regressed to glycated haemoglobin levels by a logistic regression model. RESULTS: Twenty differential metabolites were identified between the DR and control groups and were significantly enriched in five Kyoto Encyclopedia of Genes and Genomes pathways (arginine biosynthesis; tricarboxylic acid cycle; alanine, aspartate, and glutamate metabolism; tyrosine metabolism; and D-glutamate metabolism). Ferrous ascorbate significantly contributes to poorer glycaemic control outcomes, offering insights into potential new pathogenic pathways in DR. CONCLUSIONS: Disorders in the metabolic pathways of arginine biosynthesis, tricarboxylic acid cycle, alanine, aspartate, glutamate metabolism, tyrosine metabolism, and D-glutamate metabolism were associated with DR. Risk scores based on vitreous fluid metabolites can be used for the diagnosis and management of DR. Ferrous ascorbate can provide insights into potential new pathogenic pathways for DR.


Asunto(s)
Ácido Ascórbico , Biomarcadores , Retinopatía Diabética , Metabolómica , Cuerpo Vítreo , Humanos , Retinopatía Diabética/metabolismo , Retinopatía Diabética/diagnóstico , Cuerpo Vítreo/metabolismo , Biomarcadores/metabolismo , Masculino , Metabolómica/métodos , Femenino , Persona de Mediana Edad , Ácido Ascórbico/metabolismo , Anciano , Cromatografía Líquida de Alta Presión
15.
ACS Appl Mater Interfaces ; 16(19): 25065-25070, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38712510

RESUMEN

Phase transition materials with switchable second-order nonlinear optical (NLO) properties have attracted extensive attention because of their great application potential in photoelectric switches, sensors, and modulators, while metal-free organics with NLO switchability near room temperature remain scarce. Herein, we report a hydrogen-bonded metal-free organic crystal, 2-methylpropan-2-aminium 2,2-dimethylpropanoate (1), exhibiting a room-temperature phase transition and favorable NLO switchability. Through investigations on its thermal anomalies, dielectric properties, and crystal structures, we uncover that 1 holds a near-room-temperature phase transition at 303 K from noncentrosymmetric point group C2v to centrosymmetric one D2h, which is attributed to the order-disorder transformations of both tert-butylamine cations and dimethylpropionic acid anions. Accompanied by symmetry change during the phase transition, 1 exhibits reversible and repeatable NLO "on-off" switchability with a desirable switching contrast ratio of ca. 19 between high and low NLO states. This discovery demonstrates a metal-free organic crystal with NLO switching behavior near room temperature, serving as a promising candidate in smart and ecofriendly photoelectric functional materials and devices.

16.
Org Lett ; 26(20): 4229-4234, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38738828

RESUMEN

A copper-catalyzed [3 + 2] annulation of O-acyl oximes with 4-sulfonamidophenols is developed. The advantage of this method lies in the concurrent double activation of two substrates to form nucleophilic enamines and electrophilic quinone monoimines. The substituent on the α-carbon of O-acyl oxime determines two different reaction pathways, thereby leading to the selective generation of 5-sulfonamidoindoles and 2-amido-5-sulfonamidobenzofuran-3(2H)-ones.

17.
Arch Biochem Biophys ; 754: 109962, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38499055

RESUMEN

Acetohydroxyacid synthase (AHAS) is one of the key enzymes of the biosynthesis of branched-chain amino acids, it is also an effective target for the screening of herbicides and antibiotics. In this study we present a method for preparing Escherichia coli AHAS I holoenzyme (EcAHAS I) with exceptional stability, which provides a solid ground for us to re-investigate the in vitro catalytic properties of the protein. The results show EcAHAS I synthesized in this way exhibits similar function to Bacillus subtilis acetolactate synthase in its catalysis with pyruvate and 2-ketobutyrate (2-KB) as dual-substrate, producing four 2-hydroxy-3-ketoacids including (S)-2-acetolactate, (S)-2-aceto-2-hydroxybutyrate, (S)-2-propionyllactate, and (S)-2-propionyl-2-hydroxybutyrate. Quantification of the reaction indicates that the two substrates almost totally consume, and compound (S)-2-aceto-2- hydroxybutyrate forms in the highest yield among the four major products. Moreover, the protein also condenses two molecules of 2-KB to furnish (S)-2-propionyl-2-hydroxybutyrate. Further exploration manifests that EcAHAS I ligates pyruvate/2-KB and nitrosobenzene to generate two arylhydroxamic acids N-hydroxy-N-phenylacetamide and N-hydroxy-N-phenyl- propionamide. These findings enhance our comprehension of the catalytic characteristics of EcAHAS I. Furthermore, the application of this enzyme as a catalyst in construction of C-N bonds displays promising potential.


Asunto(s)
Acetolactato Sintasa , Escherichia coli , Acetolactato Sintasa/química , Glucógeno Sintasa , Hidroxibutiratos , Piruvatos , Holoenzimas
18.
Int J Hematol ; 119(5): 564-572, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38441775

RESUMEN

OBJECTIVE: To describe the features of ETV6::ABL1 AML as well as the clinical treatment and outcomes. METHODS: Clinical data were collected from three patients diagnosed with ETV6::ABL1 AML at Hebei Yanda Lu Daopei Hospital and Beijing Lu Daopei Hospital. Their clinical and laboratory features were analyzed, and the treatment process and outcomes were described. Ten reported cases of ETV6::ABL1 AML from the literature were also included for analysis. RESULTS: The median age of the patients was 34 years, and 2 patients were male. No patient had a history of blood disorders before diagnosis. After relapse, they were referred to our hospital, where the ETV6::ABL1 gene was detected. Unfortunately, Patient 1 died rapidly after leukemia relapse due to severe infection. Patients 2 and 3 received salvage therapy with a dasatinib-containing regimen, followed by allo-HSCT, and are currently alive and disease-free. CONCLUSION: ETV6::ABL1 is a rare but recurrent genetic aberration in AML, and the combined use of fluorescence in situ hybridization and PCR can better identify this fusion gene. Patients carrying ETV6::ABL1 have a high relapse rate and a poor prognosis. TKIs are a reasonable treatment option for this group, and allo-HSCT may be curative.


Asunto(s)
Proteína ETS de Variante de Translocación 6 , Leucemia Mieloide Aguda , Proteínas de Fusión Oncogénica , Proteínas Proto-Oncogénicas c-ets , Proteínas Represoras , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Trasplante de Células Madre Hematopoyéticas , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Proteínas de Fusión Oncogénica/genética , Proteínas Proto-Oncogénicas c-abl/genética , Proteínas Proto-Oncogénicas c-ets/genética , Proteínas Represoras/genética , Resultado del Tratamiento
19.
Science ; 383(6690): 1492-1498, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38547269

RESUMEN

Transient implantable piezoelectric materials are desirable for biosensing, drug delivery, tissue regeneration, and antimicrobial and tumor therapy. For use in the human body, they must show flexibility, biocompatibility, and biodegradability. These requirements are challenging for conventional inorganic piezoelectric oxides and piezoelectric polymers. We discovered high piezoelectricity in a molecular crystal HOCH2(CF2)3CH2OH [2,2,3,3,4,4-hexafluoropentane-1,5-diol (HFPD)] with a large piezoelectric coefficient d33 of ~138 picocoulombs per newton and piezoelectric voltage constant g33 of ~2450 × 10-3 volt-meters per newton under no poling conditions, which also exhibits good biocompatibility toward biological cells and desirable biodegradation and biosafety in physiological environments. HFPD can be composite with polyvinyl alcohol to form flexible piezoelectric films with a d33 of 34.3 picocoulombs per newton. Our material demonstrates the ability for molecular crystals to have attractive piezoelectric properties and should be of interest for applications in transient implantable electromechanical devices.


Asunto(s)
Materiales Biocompatibles , Compuestos Férricos , Polímeros , Biodegradación Ambiental , Polímeros/química , Polímeros/metabolismo , Alcohol Polivinílico/química , Alcohol Polivinílico/metabolismo , Materiales Biocompatibles/química , Materiales Biocompatibles/metabolismo , Electricidad , Animales , Ratas , Ratas Sprague-Dawley , Compuestos Férricos/química , Compuestos Férricos/metabolismo
20.
Fitoterapia ; 175: 105928, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38548027

RESUMEN

α-DCs (α-dicarbonyls) have been proven to be closely related to aging and the onset and development of many chronic diseases. The wide presence of this kind of components in various foods and beverages has been unambiguously determined, but their occurrence in various phytomedicines remains in obscurity. In this study, we established and evaluated an HPLC-UV method and used it to measure the contents of four α-DCs including 3-deoxyglucosone (3-DG), glyoxal (GO), methylglyoxal (MGO), and diacetyl (DA) in 35 Chinese herbs after they have been derivatized with 4-nitro-1,2-phenylenediamine. The results uncover that 3-DG is the major component among the α-DCs, being detectable in all the selected herbs in concentrations ranging from 22.80 µg/g in the seeds of Alpinia katsumadai to 7032.75 µg/g in the fruit of Siraitia grosuenorii. The contents of the other three compounds are much lower than those of 3-DG, with GO being up to 22.65 µg/g, MGO being up to 55.50 µg/g, and DA to 18.75 µg/g, respectively. The data show as well the contents of the total four α-DCs in the herbs are generally in a comparable level to those in various foods, implying that herb medicines may have potential risks on human heath in view of the α-DCs.


Asunto(s)
Desoxiglucosa , Medicamentos Herbarios Chinos , Glioxal , Piruvaldehído , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Piruvaldehído/análisis , Cromatografía Líquida de Alta Presión , Desoxiglucosa/análogos & derivados , Desoxiglucosa/análisis , Glioxal/análisis , Diacetil/análisis , Estructura Molecular , Frutas/química , Plantas Medicinales/química , Semillas/química
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