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1.
BMC Infect Dis ; 23(1): 810, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37978351

RESUMEN

BACKGROUND: The breast milk bank is a professional organization that collects donor human milk (DHM) for special medical needs by recruiting qualified breast milk donors. Such organizations are also responsible for the disinfection, processing, testing, storage, distribution, and use of breast milk. As DHM is a biological product, it may get contaminated. Microbiological testing is the final step to determine microbial contamination of DHM. However, a universal method for the microbiological analysis of DHM in breast milk banks globally is lacking.DHM without strict screening may become a potential carrier of pathogens and seriously threaten the health of infants. Clostridium perfringens, a gram-positive anaerobic bacterium, is capable of causing wound infections, including gas gangrene, enteritis/enterocolitis, and enterotoxemia. Here, the first case of C. perfringens detected in DHM has been reported to facilitate the identification of such contamination in breast milk banks. CASE PRESENTATION: A breastfeeding mother donated 3000 mL of milk to the breast milk bank of the First Affiliated Hospital of the Army Medical University(over 2900 beds and patient receiving capacity of over 132,000), Chongqing, China. The milk sample was subjected to microbiological screening using liquid enrichment, followed by anaerobic and aerobic culturing. The results revealed the growth of C. perfringens in the anaerobic culture medium, but no bacteria or yeast-like fungi were observed in the aerobic culture medium. The donor did not exhibit any clinical symptoms, and her routine blood results and body temperature were normal. However, the infant fed with her milk had recurrent bloody stools. Breast milk bank infection control emergency handling as well as environmental sampling and investigation revealed that the cause was contamination of the donor's home-use breast pump with C. perfringens. The infant no longer experienced bloody stool once the donor changed the breast pump. CONCLUSIONS: C. perfringens can enter breast milk from contaminated pumping environments or devices, thus causing illness in infants. The microbiological testing of DHM in breast milk banks can be accomplished using liquid enrichment, along with anaerobic and aerobic culture, which is of immense significance in improving the standards for microbiological screening, DHM safety, and infant health.


Asunto(s)
Clostridium perfringens , Leche Humana , Humanos , Lactante , Femenino , Animales , Composición de Base , Filogenia , ARN Ribosómico 16S , Análisis de Secuencia de ADN , Lactancia Materna
2.
Ecotoxicol Environ Saf ; 195: 110513, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32213370

RESUMEN

The study aims to investigate effect of earthworm activity on metal bioavailability in soils using their BSAF-metals. Based on a microcosmic laboratory experiment, epigeic species Amynthas corticis (A. corticis) and endogeic species Amynthas robustus (A. robustus) were cultured in two types of soils contaminated by Cd, Zn, Pb and Cu for 120 days. Earthworm characteristics (i.e. numbers, biomass and BSAF), soil properties (i.e. pH, organic C and N contents along with their components such as mineralization and microbial masses) and DTPA extracted metals in soil were determined. After the incubation, the biomass and survival numbers of both earthworm species decreased significantly (P < 0.05). The accumulation of Cd, Zn and Pb in earthworm tissues and BSAF-metals were earthworm species dependent. According to two-way ANOVA, BSAF-Pb clearly showed the effect of different species of earthworms while BSAF-Cu indicated an interactive effect of earthworms and soil type. Earthworms changed soil properties significantly, especially for mineralized C (Cmin), dissolved N (Ndis) and pH (P < 0.05). Earthworm activity increase DTPA extracted Zn and Cu, and the effect of A. robustus were stronger than for A. corticis. Redundancy analysis (RDA) showed that BSAF-Cu and BSAF-Pb contributed for respectively 51.9% and 51.7% of soil properties and DTPA metal changes, indicating that the effects of BSAF-Cu and BSAF-Pb on soil properties and on metal bioavailability in soil were similar. BSAF-Cu, indicating the interactive effect of earthworms and soil, accounted for 38.5% and 45.1% of soil properties and soil metal bioavailability changes. BSAF-Pb, representing the effect of earthworm species, accounted for 13.3% and 6.6% of soil property and soil metal bioavailability variations. Stepwise regression indicated that earthworm might change soil properties through their activities and interactions with soil, and hence increase heavy metal bioavailability. It suggested that BSAF is an important indicator for evaluating the effect of earthworm activity on soil metal bioavailability and designing remediation strategies.


Asunto(s)
Conducta Animal/efectos de los fármacos , Metales Pesados/análisis , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/análisis , Suelo/química , Animales , Disponibilidad Biológica , Biota , Cadmio/análisis , Cobre/análisis , Plomo/análisis , Modelos Teóricos , Oligoquetos/química , Oligoquetos/fisiología , Ácido Pentético/química , Zinc/análisis
3.
Bioorg Chem ; 88: 102832, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31102809

RESUMEN

Epilepsy is a group of neurological disorders characterized by recurrent seizures that disturbs about 60 million people worldwide. In this article, a novel series of 3,4,5-trimethoxycinnamic acid (TMCA) ester derivatives 1-35 were designed inspired from the traditional Chinese herb pair drugs Polygala tenuifolia and Gastrodia elata and synthesized followed by in vivo and in silico evaluation of their anticonvulsant potential. All the synthesized derivatives were biologically evaluated for their anticonvulsant potential using two acute model of seizures induced in mice, the maximal electroshock (MES) and sc-pentylenetetrazole (PTZ) models. Simultaneously, the motor impairment as a surrogate of acute neurotoxicity and in vitro screening of cytotoxicity against HepG-2 cells line were assessed through the rotarod performance test and CCK-8 assay, respectively. In addition, the physicochemical and pharmacokinetic parameters of the active compounds were determined. Our results showed that compounds 5, 7, 8, 13, 20, 25, 28, 30 and 32 exhibited preferable anticonvulsant activity in primary evaluation, with compounds 28 and 32 being the most promising anticonvulsant agents in according to results of subsequent pharmacology and toxicity evaluation. Additionally, the molecular modeling experiments predicted good binding interactions of part of the obtained active molecules with the gamma-aminobutyric acid (GABA) transferas. Therefore, it could be concluded that the synthesized derivatives 28 and 32 would represent useful lead compounds for further investigation in the development of anticonvulsant agents.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Cinamatos/uso terapéutico , Convulsiones/tratamiento farmacológico , 4-Aminobutirato Transaminasa/química , 4-Aminobutirato Transaminasa/metabolismo , Animales , Anticonvulsivantes/síntesis química , Anticonvulsivantes/metabolismo , Anticonvulsivantes/farmacología , Sitios de Unión , Cinamatos/síntesis química , Cinamatos/metabolismo , Cinamatos/farmacología , Diseño de Fármacos , Epilepsia/tratamiento farmacológico , Gastrodia/química , Células Hep G2 , Humanos , Masculino , Ratones , Simulación del Acoplamiento Molecular , Estructura Molecular , Pentilenotetrazol , Polygala/química , Unión Proteica , Convulsiones/inducido químicamente , Relación Estructura-Actividad , Porcinos
4.
Bioorg Chem ; 93: 103316, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31585271

RESUMEN

This study aimed to synthesize and screen tyrosinase inhibitors for delay fruit browning. A series of vanillyl cinnamate analogues were designed and synthesized by simple processes, and the inhibitory effects of all the synthesized derivatives on mushroom tyrosinase were evaluated. In the enzymatic activity test, compounds 21, 22, and 26 had significant (P < 0.05) effect on mushroom tyrosinase at a preliminary screening dose (1 mg/mL in vitro). IC50 analysis showed that the IC50 values of compounds 21, 22 and 26 were 268.5 µM, 213.2 µM and 413.5 µM, respectively. In the cytotoxicity evaluation, Cell Counting Kit-8 (CCK-8) assay showed that compounds 21, 22 and 26 had no significant effect on the proliferation of hepatocyte L02 and B16 melanoma cells at the dosage of 25-200 µM. Inhibition of tyrosinase activity and melanin content in B16 melanoma cells investigations indicated that compounds 21, 22 and 26 inhibited both cellular tyrosinase activity and melanin content dose-dependently and more strongly than the reference standard arbutin. The UV-visible spectra showed compound 22 inhibits the formation of dopamine quinone, further the molecular docking analysis of compound 22 with tyrosinase (PDB: 2Y9X) indicated that compound 22 interacted with the amino acid residues of tyrosinase. The results of anti-browning test showed that compounds 21, 22 and 26 had significant tyrosinase inhibition and anti-browning effects on fresh-cut apple slices at 4 °C in 48 h. Compound 22 could be used as novel tyrosinase inhibitor to delay fruit browning.


Asunto(s)
Cinamatos/metabolismo , Inhibidores Enzimáticos/síntesis química , Monofenol Monooxigenasa/antagonistas & inhibidores , Agaricales/enzimología , Animales , Sitios de Unión , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cinamatos/química , Cinamatos/farmacología , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Cinética , Melaninas/antagonistas & inhibidores , Melaninas/metabolismo , Ratones , Simulación del Acoplamiento Molecular , Monofenol Monooxigenasa/metabolismo , Estructura Terciaria de Proteína , Relación Estructura-Actividad
6.
Oecologia ; 183(2): 455-467, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27844148

RESUMEN

Stand diversification is considered a promising management approach to increasing the multifunctionality and ecological stability of forests. However, how tree diversity affects higher trophic levels and their role in regulating forest functioning is not well explored particularly for (sub)tropical regions. We analyzed the effects of tree species richness, community composition, and functional diversity on the abundance, species richness, and beta diversity of important functional groups of herbivores and predators in a large-scale forest biodiversity experiment in south-east China. Tree species richness promoted the abundance, but not the species richness, of the dominant, generalist herbivores (especially, adult leaf chewers), probably through diet mixing effects. In contrast, tree richness did not affect the abundance of more specialized herbivores (larval leaf chewers, sap suckers) or predators (web and hunting spiders), and only increased the species richness of larval chewers. Leaf chemical diversity was unrelated to the arthropod data, and leaf morphological diversity only positively affected oligophagous herbivore and hunting spider abundance. However, richness and abundance of all arthropods showed relationships with community-weighted leaf trait means (CWM). The effects of trait diversity and CWMs probably reflect specific nutritional or habitat requirements. This is supported by the strong effects of tree species composition and CWMs on herbivore and spider beta diversity. Although specialized herbivores are generally assumed to determine herbivore effects in species-rich forests, our study suggests that generalist herbivores can be crucial for trophic interactions. Our results indicate that promoting pest control through stand diversification might require a stronger focus on identifying the best-performing tree species mixtures.


Asunto(s)
Herbivoria , Árboles , Animales , Biodiversidad , Ecosistema , Bosques
7.
Molecules ; 22(9)2017 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-28837110

RESUMEN

This paper is intended to review advances in the botanical, phytochemical, traditional uses and pharmacological studies of the genus Trachelospermum. Until now, 138 chemical constituents have been isolated and characterized from these plants, particularly from T. asiaticum and T. jasminoides. Among these compounds, lignans, triterpenoids, and flavonoids are the major bioactive constituents. Studies have shown that plants from the genus Trachelospermum exhibit an extensive range of pharmacological properties both in vivo and in vitro, including anti-inflammatory, analgesic, antitumor, antiviral and antibacterial activities. In Traditional Chinese Medicine (TCM) culture, drugs that include T. jasminoides stems have been used to cure rheumatism, gonarthritis, backache and pharyngitis, although there are few reports concerning the clinical use and toxicity of these plants. Further attention should be paid to gathering information about their toxicology data, quality-control measures, and the clinical value of the active compounds from genus Trachelospermum.


Asunto(s)
Apocynaceae/química , Fitoquímicos/química , Fitoquímicos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Animales , Humanos , Medicina Tradicional
8.
Molecules ; 22(11)2017 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-29099799

RESUMEN

Under the guidance of combination of traditional Chinese medicine chemistry (CTCMC), this study describes the preparation of a phenolic acid/dipeptide/borneol hybrid consisting of phenolic acid and a bornyl moiety connected to the dipeptide N-terminal and C-terminal respectively. It also evaluates their angiotensin converting enzyme (ACE) inhibitory and synergistic antihypertensive activities. Briefly, a series of novel 2-hydroxypyrrolobenzodiazepine-5,11-dione analogues were prepared and investigated for their ability to inhibit ACE. The influence of the phenolic acid and bornyl moiety on subsite selectivity is also demonstrated. Among all the new compounds, two compounds-7a and 7g-reveal good inhibition potency in in vitro ACE-inhibitory tests. Interestingly, favorable binding results in molecular docking studies also supported the in vitro results. Additionally, the bioassay showed that oral administration of the two compounds displayed high and long-lasting antihypertensive activity both in acute antihypertensive tests and in therapeutic antihypertensive tests by non-invasive blood pressure measurements in spontaneously hypertensive rats.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/síntesis química , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Antihipertensivos/síntesis química , Antihipertensivos/farmacología , Benzodiazepinas/síntesis química , Benzodiazepinas/farmacología , Hipertensión/tratamiento farmacológico , Pirroles/síntesis química , Pirroles/farmacología , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Animales , Antihipertensivos/efectos adversos , Benzodiazepinas/efectos adversos , Sitios de Unión , Presión Sanguínea/efectos de los fármacos , Diseño de Fármacos , Simulación del Acoplamiento Molecular/métodos , Estructura Molecular , Unión Proteica , Pirroles/efectos adversos , Ratas Endogámicas SHR , Relación Estructura-Actividad
9.
Ultrasonics ; 140: 107307, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38579486

RESUMEN

BACKGROUND AND OBJECTIVE: With the development of advanced clutter-filtering techniques by singular value decomposition (SVD) and leveraging favorable acquisition settings such as open-chest imaging by a linear high-frequency probe and plane waves, several studies have shown the feasibility of cardiac flow measurements during the entire cardiac cycle, ranging from coronary flow to myocardial perfusion. When applying these techniques in a routine clinical setting, using transthoracic ultrasound imaging, new challenges emerge. Firstly, a smaller aperture is needed that can fit between ribs. Consequently, diverging waves are employed instead of plane waves to achieve an adequate field of view. Secondly, to ensure imaging at a larger depth, the maximum pulse repetition frequency has to be reduced. Lastly, in comparison to the open-chest scenario, tissue motion induced by the heartbeat is significantly stronger. The latter complicates substantially the distinction between clutter and blood signals. METHODS: This study investigates a strategy to overcome these challenges by diverging wave imaging with an optimal number of tilt angles, in combination with dedicated clutter-filtering techniques. In particular, a novel, adaptive, higher-order SVD (HOSVD) clutter filter, which utilizes spatial, temporal, and angular information of the received ultrasound signals, is proposed to enhance clutter and blood separation. RESULTS: When non-negligible tissue motion is present, using fewer tilt angles not only reduces the decorrelation between the received waveforms but also allows for collecting more temporal samples at a given ensemble duration, contributing to improved Doppler performance. The addition of a third angular dimension enables the application of HOSVD, providing greater flexibility in selecting blood separation thresholds from a 3-D tensor. This differs from the conventional threshold selection method in a 2-D spatiotemporal space using SVD. Exhaustive threshold search has shown a significant improvement in Contrast and Contrast-to-Noise ratio for Power Doppler images filtered with HOSVD compared to the SVD-based clutter filter. CONCLUSION: With the improved settings, the obtained Power Doppler images show the feasibility of measuring coronary flow under the influence of non-negligible tissue motion in both in vitro and ex vivo.


Asunto(s)
Circulación Coronaria , Circulación Coronaria/fisiología , Fantasmas de Imagen , Animales , Humanos , Algoritmos , Ecocardiografía Doppler/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Velocidad del Flujo Sanguíneo/fisiología , Porcinos
10.
Case Rep Ophthalmol Med ; 2024: 5519361, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38566845

RESUMEN

Background: Here, we report a case of a male patient with bilateral focal choroidal excavation (FCE) and central serous chorioretinopathy (CSC). A 33-year-old man complained of mild blurring of vision in the right eye. Optical coherence tomography (OCT) revealed FCE in both eyes, with subretinal fluid in both eyes and serous pigment epithelial detachment in the right eye. Standard laser fluence (50 J/cm2) was used in the right eye, and a subthreshold micropulse laser (SML) was simultaneously used in the left eye. Follow-up visits were recommended. At his last visit (5 months after treatment), the visual acuity was 16/20 in the right eye and 20/20 in the left eye and OCT showed a completed resolution of SRF. Conclusion: FCE is defined as a localized depression of the choroid detected by OCT. It may be congenital or acquired secondarily. We present a case of uncommon focal choroidal excavation and central serous chorioretinopathy (CSC) coexisting in both eyes at a relatively young age in which visual acuity was improved and subretinal fluid (SRF) completely resolved with laser treatment. Timely treatment can promote SRF absorption and improve vision.

11.
Artículo en Inglés | MEDLINE | ID: mdl-38526897

RESUMEN

Ultrasound elastography (USE) is a promising tool for tissue characterization as several diseases result in alterations of tissue structure and composition, which manifest as changes in tissue mechanical properties. By imaging the tissue response to an applied mechanical excitation, USE mimics the manual palpation performed by clinicians to sense the tissue elasticity for diagnostic purposes. Next to elasticity, viscosity has recently been investigated as an additional, relevant, diagnostic biomarker. Moreover, since biological tissues are inherently viscoelastic, accounting for viscosity in the tissue characterization process enhances the accuracy of the elasticity estimation. Recently, methods exploiting different acquisition and processing techniques have been proposed to perform ultrasound viscoelastography. After introducing the physics describing viscoelasticity, a comprehensive overview of the currently available USE acquisition techniques is provided, followed by a structured review of the existing viscoelasticity estimators classified according to the employed processing technique. These estimators are further reviewed from a clinical usage perspective, and current outstanding challenges are discussed.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Diagnóstico por Imagen de Elasticidad/métodos , Humanos , Viscosidad , Procesamiento de Imagen Asistido por Computador/métodos
12.
Fitoterapia ; 177: 106095, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38942299

RESUMEN

Peptidyl arginine deiminase 4 (PAD4) is a promising target for the treatment of metabolic diseases associated with autoimmune and central nervous system disease. By now there are limited numbers of PAD4 inhibitors, and no one is ready for clinical use. This study aims to find efficient and specific PAD4 inhibitors from traditional herbal medicines and to investigate their inhibitory mechanisms. The inhibitory effects of forty-eight extracts from sixteen traditional herbal medicines which are widely used in traditional herbal medicines were investigated. Salvia miltiorrhiza was found to have the most potent PAD4 inhibitory activity. After that, a practical bioactivity-guided fractionation coupling with a chemical profiling strategy was used to identify the fractions from Salvia miltiorrhiza with strong PAD4 inhibition activity, and the major constituents in these bioactive fractions were characterized by LC-MS/MS. Seven compounds were found to have inhibition on PAD4 with IC50 values ranging from 33.52 µM to 667 µM, in which salvianolic acid A showed the most potent inhibitory activity, with an IC50 value of 33.52 µM. Inhibition kinetic analyses indicated that salvianolic acid A effectively inhibited PAD4 in a mixed inhibitory manner, and computer simulation analyses demonstrated that salvianolic acid A binds to PAD4 mainly using hydrogen bonding. Overall, our results suggest that salvianolic acid A from Salvia miltiorrhiza is a potent inhibitor of PAD4, and that salvianolic acid A can be used as a promising lead compound for the development of more potent PAD4 inhibitors.

13.
Mol Med Rep ; 29(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38516772

RESUMEN

Remifentanil­induced hyperalgesia (RIH) is characterized by the emergence of stimulation­induced pain, including phenomena such as allodynia and thermal hyperalgesia following remifentanil infusion. As a sequence­specific DNA binding transcription factor, PAX6 positively and negatively regulates transcription and is expressed in multiple cell types in the developing and adult central nervous system. It was hypothesized that puerarin could relieve RIH via targeting PAX6 to regulate transcription of transient receptor potential cation channel subfamily V Member 1 (TRPV1). A total of 32 rats were randomly divided into five groups, namely control group, RI group, RI + 10 mg/kg puerarin group (RI + puerarin10), RI + 20 mg/kg puerarin group (RI + puerarin20), and RI + 40 mg/kg puerarin group (RI + puerarin40). Mechanical and thermal hyperalgesia were tested at ­24, 2, 6, 24 and 48 h after remifentanil infusion. Following the sacrifice of rats after the last behavioral test, western blot was used to detect the expression levels of TRPV1 in the tissues; Immunofluorescence staining and western blotting were used to detect the expression of PAX6 in the spinal cord. PharmMapper and JASPAR were used to predict the binding sites of puerarin/PAX6/TRPV1. Chromatin immunoprecipitation­PCR and dual luciferase reporter assay were used to verify the targeting relationship between PAX6 and TRPV1. Immunofluorescence was used to detect the expression levels of TRPV1 and p­NR2B. The results revealed that puerarin (10, 20, 40 mg/kg) dose­dependently reduced thermal and mechanical hyperalgesia from 2 to 48 h after remifentanil infusion. Remifentanil infusion remarkably stimulated the expression of phosphorylated (p­)NR2B. Nevertheless, the increased amount of p­NR2B by RIH was dose­dependently suppressed by puerarin in rats. In conclusion, puerarin was revealed to attenuate postoperative RIH via targeting PAX6 to regulate the transcription of TRPV1.


Asunto(s)
Hiperalgesia , Isoflavonas , Animales , Ratas , Hiperalgesia/inducido químicamente , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/genética , Isoflavonas/farmacología , Isoflavonas/uso terapéutico , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/etiología , Piperidinas/farmacología , Ratas Sprague-Dawley , Remifentanilo/efectos adversos , Factor de Transcripción PAX6/efectos de los fármacos , Factor de Transcripción PAX6/metabolismo , Canales Catiónicos TRPV/efectos de los fármacos , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo
14.
J Chromatogr A ; 1716: 464643, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38232639

RESUMEN

Peptidyl arginine deiminase 4 (PAD4) is an important biocatalytic enzymes involved in the conversion of protein arginine to citrulline, its dysregulation has a great impact on many physiological processes. Recently, PAD4 has emerged as a potential therapeutic target for the treatment of various diseases including rheumatoid arthritis (RA). Traditional Chinese Medicines (TCMs), also known as herbal plants, have gained great attention by the scientific community due to their good therapeutic performance and far fewer side effects observed in the clinical treatment. However, limited researches have been reported to screen natural PAD4 inhibitors from herbal plants. The color developing reagent (COLDER) or fluorescence based methods have been widely used in PAD4 activity assay and inhibitor screening. However, both methods measure the overall absorbance or fluorescence in the reaction solution, which are easy to be affected by the background interference due to colorful extracts from herbal plants. In this study, a simple, and robust high-performance liquid chromatography ultraviolet-visible (HPLC-UV) based method was developed to determine PAD4 activity. The proposed strategy was established based on COLDER principle, while used hydrophilic l-arginine instead of hydrophobic N-benzoyl-l-arginine ethyl ester (BAEE) as a new substrate to determine PAD4 inhibition activity of herbal extracts. The herbal extracts and PAD4 generated hydrophobic l-citrulline were successfully separated by the HPLC, and the developed method was optimized and validated with a known PAD4 inhibitor (GSK484) in comparison with COLDER assay. The IC50 value of GSK484 measured by HPLC-UV method was 153 nM, and the detection limit of the citrulline was 0.5 nmol, respectively, with a linear range of 0.5 nmol to 20 nmol. The IC50 value of the HPLC-UV method was improved by nearly three times compared with COLDER assay (527 nM), and the results indicated the reliability of PAD4 inhibition via HPLC-UV method. The inhibitory effect against PAD4 were fast and accurately screened for the twenty-four extracts from eight herbs. Among them, Ephedra Herba extracts showed significant inhibitory activity against the PAD4 with the IC50 values of three extracts (ethanol, ethyl acetate and water) ranging from 29.11 µg/mL to 41.36 µg/mL, which may help researchers to discover novel natural compounds holding high PAD4 inhibition activity.


Asunto(s)
Productos Biológicos , Medicamentos Herbarios Chinos , Inhibidores Enzimáticos , Arginina Deiminasa Proteína-Tipo 4 , Cromatografía Líquida de Alta Presión , Citrulina , Arginina Deiminasa Proteína-Tipo 4/antagonistas & inhibidores , Reproducibilidad de los Resultados , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Inhibidores Enzimáticos/farmacología , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Medicamentos Herbarios Chinos/química
15.
Se Pu ; 42(7): 711-720, 2024 Jul.
Artículo en Zh | MEDLINE | ID: mdl-38966979

RESUMEN

Protein citrullination is an irreversible post-translational modification process regulated by peptidylarginine deiminases (PADs) in the presence of Ca2+. This process is closely related to the occurrence and development of autoimmune diseases, cancers, neurological disorders, cardiovascular and cerebrovascular diseases, and other major diseases. The analysis of protein citrullination by biomass spectrometry confronts great challenges owing to its low abundance, lack of affinity tags, small mass-to-charge ratio change, and susceptibility to isotopic and deamidation interferences. The methods commonly used to study the protein citrullination mainly involve the chemical derivatization of the urea group of the guanine side chain of the peptide to increase the mass-to-charge ratio difference of the citrullinated peptide. Affinity-enriched labels are then introduced to effectively improve the sensitivity and accuracy of protein citrullination by mass spectrometry. 2,3-Butanedione or phenylglyoxal compounds are often used as derivatization reagents to increase the mass-to-charge ratio difference of the citrullinated peptide, and the resulting derivatives have been observed to contain α-dicarbonyl structures. To date, however, no relevant studies on the reactivity of dicarbonyl compounds with citrullinated peptides have been reported. In this study, we determined whether six α-dicarbonyl and two ß-dicarbonyl compounds undergo derivatization reactions with standard citrullinated peptides using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF MS). Among the α-dicarbonyl compounds, 2,3-butanedione and glyoxal reacted efficiently with several standard citrullinated peptides, but yielded a series of by-products. Phenylglyoxal, methylglyoxal, 1,2-cyclohexanedione, and 1,10-phenanthroline-5,6-dione also derivated efficiently with standard citrullinated peptides, generating a single derivative. Thus, a new derivatization method that could yield a single derivative was identified. Among the ß-dicarbonyl compounds, 1,3-cyclohexanedione and 2,4-pentanedione successfully reacted with the standard citrullinated peptides, and generated a single derivative. However, their reaction efficiency was very low, indicating that the ß-dicarbonyl compounds are unsuitable for the chemical derivatization of citrullinated peptides. The above results indicate that the α-dicarbonyl structure is necessary for realizing the efficient and specific chemical derivatization of citrullinated peptides. Moreover, the side chains of the α-dicarbonyl structure determine the structure of the derivatives, derivatization efficiency, and generation (or otherwise) of by-products. Therefore, the specific enrichment and precise identification of citrullinated peptides can be achieved by synthesizing α-dicarbonyl structured compounds containing affinity tags. The proposed method enables the identification of citrullinated proteins and their modified sites by MS, thereby providing a better understanding of the distribution of citrullinated proteins in different tissues. The findings will be beneficial for studies on the mechanism of action of citrullinated proteins in a variety of diseases.


Asunto(s)
Citrulinación , Péptidos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Péptidos/química
16.
Int J Biol Macromol ; 259(Pt 1): 129175, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38181916

RESUMEN

Armillaria mellea (Vahl) P. Kumm. is a well-known homoeopathic plant with medicinal and culinary uses. Modern phytochemical researchers have successfully extracted and purified over 40 types of A. mellea polysaccharides (AMPs) from the fruiting bodies, hyphae and fermentation broth of A. mellea, and some of them have been analyzed and identified by their chemical structures. The impressive biological activity of these polysaccharides has been recognized by scientists worldwide. Many studies show that AMPs have remarkable antioxidant, anti-diabetic, anti-tumor, anti-inflammatory, immunoregulatory, hypolipidemic, thrombectomy, anti-aging, pulmonary protective, hepatic protective, anti-Alzheimer's properties, etc. However, the current understanding of the relationships between their chemical structure and biological activity, toxicological effects and pharmacokinetics remains limited. This article provides a systematic review of the research conducted over the past decades on the extraction and purification methods, structural characteristics, biological activity and mechanism of action of AMPs. The aim is to provide a research base that will benefit the future application of AMPs as therapeutic drugs and functional foods, and also provide insights for the further development of AMPs.


Asunto(s)
Armillaria , Polisacáridos , Polisacáridos/farmacología , Armillaria/química , Antioxidantes/farmacología , Antioxidantes/química , Antiinflamatorios/farmacología
17.
Diabetes Metab J ; 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38408883

RESUMEN

Background: Diabetes-induced cardiac fibrosis is one of the main mechanisms of diabetic cardiomyopathy. As a common histone methyltransferase, enhancer of zeste homolog 2 (EZH2) has been implicated in fibrosis progression in multiple organs. However, the mechanism of EZH2 in diabetic myocardial fibrosis has not been clarified. Methods: In the current study, rat and mouse diabetic model were established, the left ventricular function of rat and mouse were evaluated by echocardiography and the fibrosis of rat ventricle was evaluated by Masson staining. Primary rat ventricular fibroblasts were cultured and stimulated with high glucose (HG) in vitro. The expression of histone H3 lysine 27 (H3K27) trimethylation, EZH2, and myocardial fibrosis proteins were assayed. Results: In STZ-induced diabetic ventricular tissues and HG-induced primary ventricular fibroblasts in vitro, H3K27 trimethylation was increased and the phosphorylation of EZH2 was reduced. Inhibition of EZH2 with GSK126 suppressed the activation, differentiation, and migration of cardiac fibroblasts as well as the overexpression of the fibrotic proteins induced by HG. Mechanical study demonstrated that HG reduced phosphorylation of EZH2 on Thr311 by inactivating AMP-activated protein kinase (AMPK), which transcriptionally inhibited peroxisome proliferator-activated receptor γ (PPAR-γ) expression to promote the fibroblasts activation and differentiation. Conclusion: Our data revealed an AMPK/EZH2/PPAR-γ signal pathway is involved in HG-induced cardiac fibrosis.

18.
Phytochemistry ; 210: 113626, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36871902

RESUMEN

A. calamus var. angustatus Besser is an important traditional medicinal herb commonly used in China and other Asian countries. This study is the first systematic review of the literature to thoroughly analyze the ethnopharmacological application, phytochemistry, pharmacology, toxicology and pharmacokinetic properties of A. calamus var. angustatus Besser and provides a rationale for future research and prospects for application in clinical treatment. Information on relevant studies investigating A. calamus var. angustatus Besser was collected from SciFinder, the Web of Science, PubMed, CNKI, Elsevier, ResearchGate, ACS, Flora of China, and Baidu Scholar, etc. up to December 2022. In addition, information was also obtained from Pharmacopeias, books on Chinese herbal classics, local books, as well as PhD and MS dissertations. A. calamus var. angustatus Besser has played an important role in the herbal treatment of coma, convulsion, amnesia, and dementia for thousands of years. Studies investigating the chemical constituents of A. calamus var. angustatus Besser have isolated and identified 234 small-molecule compounds and a few polysaccharides. Among them, simple phenylpropanoids represented by asarone analogues and lignans are the two main active ingredients, which can be considered characteristic chemotaxonomic markers of this herb. In vitro and in vivo pharmacological studies indicated that crude extracts and active compounds from A. calamus var. angustatus Besser display a wide range of pharmacological activities, especially as treatment for Alzheimer's disease (AD), and anticonvulsant, antidepressant-like, anxiolytic-like, anti-fatigue, anti-Parkinson, neuroprotection, and brain protection properties, providing more evidence to explain the traditional medicinal uses and ethnopharmacology. The clinical therapeutic dose of A. calamus var. angustatus Besser does not present any toxic effects, but its main active ingredients α-asarone and ß-asarone at excessive dose may lead to toxicity, and in particular, their respective epoxide metabolites may exert potential toxicity to the liver. This review provides a reference and further information for the future development and clinical application of A. calamus var. angustatus Besser.


Asunto(s)
Acorus , Medicamentos Herbarios Chinos , Plantas Medicinales , Medicamentos Herbarios Chinos/química , Etnofarmacología , Medicina Tradicional China , Fitoquímicos , Extractos Vegetales/química
19.
Colloids Surf B Biointerfaces ; 222: 113080, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36542952

RESUMEN

In this study, a novel method was developed to encapsulate hydrophobic compounds by self-assembly of cod protein (CP) triggered by breaking disulfide bonds. Curcumin (Cur), a representative lipid-soluble polyphenol, was selected as a model to evaluate the potential of CP nanoparticles as novel and accessible nanocarriers. Results showed that the protein structure gradually unfolded with increasing dithiothreitol (DTT) concentration, indicating that S-S cleavage was conducive to forming a looser structure. The resultant unfolded CP exposed more hydrophobic sites, facilitating its interaction with hydrophobic compounds. The encapsulation efficiency (EE) of formed CP-Cur nanoparticles was relatively high, reaching 99.09%, 98.8%, and 89.77% when the mass ratios of CP to Cur were 20:1, 10:1, and 5:1 (w/v), respectively. The hydrophobic interaction, weak van der Waals, and hydrogen bond were the forces contributing to the formation of CP-Cur nanoparticles, whereas the hydrophobic interaction played a crucial role. The CP-Cur complex exhibited increased stability and a homogeneous-stable structural phase. Thus, this research not only proposed a novel and simple encapsulation method of hydrophobic bioactive compounds but also provided a theoretical reference for the application of reductants in food or pharmacy system.


Asunto(s)
Curcumina , Nanopartículas , Portadores de Fármacos/química , Curcumina/química , Disulfuros , Nanopartículas/química , Tamaño de la Partícula
20.
Ultrasound Med Biol ; 49(7): 1518-1526, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37088606

RESUMEN

OBJECTIVE: Tissue mechanical properties are valuable markers for tissue characterization, aiding in the detection and staging of pathologies. Shear wave elastography (SWE) offers a quantitative assessment of tissue mechanical characteristics based on the SW propagation profile, which is derived from the SW particle motion. Improving the signal-to-noise ratio (SNR) of the SW particle motion would directly enhance the accuracy of the material property estimates such as elasticity or viscosity. METHODS: In this paper, we present a 3-D multi-resolution convolutional neural network (MRCNN) to perform improved estimation of the SW particle velocity Vz. Additionally, we propose a novel approach to generate training data from real acquisitions, providing high SNR ground truth target data, one-to-one paired to inputs that are corrupted with real-world noise and disturbances. DISCUSSION: By testing the network on in vitro data acquired from a commercial breast elastography phantom, we show that the MRCNN outperforms Loupas' autocorrelation algorithm with an improved SNR of 4.47 dB for the Vz signals, a two-fold decrease in the standard deviation of the downstream elasticity estimates, and a two-fold increase in the contrast-to-noise ratio of the elasticity maps. The generalizability of the network was further demonstrated with a set of ex vivo porcine liver data. CONCLUSION: The proposed MRCNN outperforms the standard autocorrelation method, in particular in low SNR regimes.


Asunto(s)
Diagnóstico por Imagen de Elasticidad , Animales , Porcinos , Diagnóstico por Imagen de Elasticidad/métodos , Hígado/diagnóstico por imagen , Redes Neurales de la Computación , Algoritmos , Relación Señal-Ruido , Fantasmas de Imagen
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