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1.
Immunity ; 54(9): 2042-2056.e8, 2021 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-34407391

RESUMEN

Recruitment of immune cells to the site of inflammation by the chemokine CCL1 is important in the pathology of inflammatory diseases. Here, we examined the role of CCL1 in pulmonary fibrosis (PF). Bronchoalveolar lavage fluid from PF mouse models contained high amounts of CCL1, as did lung biopsies from PF patients. Immunofluorescence analyses revealed that alveolar macrophages and CD4+ T cells were major producers of CCL1 and targeted deletion of Ccl1 in these cells blunted pathology. Deletion of the CCL1 receptor Ccr8 in fibroblasts limited migration, but not activation, in response to CCL1. Mass spectrometry analyses of CCL1 complexes identified AMFR as a CCL1 receptor, and deletion of Amfr impaired fibroblast activation. Mechanistically, CCL1 binding triggered ubiquitination of the ERK inhibitor Spry1 by AMFR, thus activating Ras-mediated profibrotic protein synthesis. Antibody blockade of CCL1 ameliorated PF pathology, supporting the therapeutic potential of targeting this pathway for treating fibroproliferative lung diseases.


Asunto(s)
Quimiocina CCL1/metabolismo , Fibroblastos/metabolismo , Proteínas de la Membrana/metabolismo , Miofibroblastos/metabolismo , Fosfoproteínas/metabolismo , Fibrosis Pulmonar/metabolismo , Receptores del Factor Autocrino de Motilidad/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Diferenciación Celular/fisiología , Fibroblastos/patología , Humanos , Ratones , Miofibroblastos/patología , Fibrosis Pulmonar/patología , Transducción de Señal/fisiología
2.
Immunity ; 51(3): 522-534.e7, 2019 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-31471107

RESUMEN

Although recent progress provides mechanistic insights into the pathogenesis of pulmonary fibrosis (PF), rare anti-PF therapeutics show definitive promise for treating this disease. Repeated lung epithelial injury results in injury-repairing response and inflammation, which drive the development of PF. Here, we report that chronic lung injury inactivated the ubiquitin-editing enzyme A20, causing progressive accumulation of the transcription factor C/EBPß in alveolar macrophages (AMs) from PF patients and mice, which upregulated a number of immunosuppressive and profibrotic factors promoting PF development. In response to chronic lung injury, elevated glycogen synthase kinase-3ß (GSK-3ß) interacted with and phosphorylated A20 to suppress C/EBPß degradation. Ectopic expression of A20 or pharmacological restoration of A20 activity by disturbing the A20-GSK-3ß interaction accelerated C/EBPß degradation and showed potent therapeutic efficacy against experimental PF. Our study indicates that a regulatory mechanism of the GSK-3ß-A20-C/EBPß axis in AMs may be a potential target for treating PF and fibroproliferative lung diseases.


Asunto(s)
Proteína beta Potenciadora de Unión a CCAAT/metabolismo , Macrófagos/metabolismo , Fibrosis Pulmonar/metabolismo , Factores de Transcripción/metabolismo , Ubiquitina/metabolismo , Animales , Línea Celular , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Células HEK293 , Humanos , Inflamación/metabolismo , Ratones , Ratones Endogámicos C57BL , Fosforilación/fisiología , Transducción de Señal/fisiología , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación/fisiología , Regulación hacia Arriba/fisiología
4.
J Org Chem ; 89(14): 9972-9978, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38954774

RESUMEN

The incorporation of oxygen atoms from air under aerobic conditions plays an important role in organic synthesis. Herein, Brønsted acids are found to be a two-in-one strategic catalyst to transform enamines from ß-oxoamides and amines to pyrrolin-4-ones without an external photocatalyst under visible-light conditions. The Brønsted acid can inhibit the C-C bond fragmentation of the [2 + 2] adduct from enamine and 1O2, but most importantly, it can form photosensitizers with enamine and pyrrolin-4-one product by acidochromism to promote the 1O2 generation.

5.
Int J Mol Sci ; 25(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38474292

RESUMEN

E0703, a new steroidal compound optimized from estradiol, significantly increased cell proliferation and the survival rate of KM mice and beagles after ionizing radiation. In this study, we characterize its preclinical pharmacokinetics (PK) and predict its human PK using a physiologically based pharmacokinetic (PBPK) model. The preclinical PK of E0703 was studied in mice and Rhesus monkeys. Asian human clearance (CL) values for E0703 were predicted from various allometric methods. The human PK profiles of E0703 (30 mg) were predicted by the PBPK model in Gastro Plus software 9.8 (SimulationsPlus, Lancaster, CA, USA). Furthermore, tissue distribution and the human PK profiles of different administration dosages and forms were predicted. The 0.002 L/h of CL and 0.005 L of Vss in mice were calculated and optimized from observed PK data. The plasma exposure of E0703 was availably predicted by the CL using the simple allometry (SA) method. The plasma concentration-time profiles of other dosages (20 and 40 mg) and two oral administrations (30 mg) were well-fitted to the observed values. In addition, the PK profile of target organs for E0703 exhibited a higher peak concentration (Cmax) and AUC than plasma. The developed E0703-PBPK model, which is precisely applicable to multiple species, benefits from further clinical development to predict PK in humans.


Asunto(s)
Protectores contra Radiación , Ratones , Humanos , Animales , Perros , Modelos Biológicos , Administración Oral , Distribución Tisular , Farmacocinética
7.
FASEB J ; 36(9): e22494, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35976173

RESUMEN

In a rat middle cerebral artery occlusion (MACo) model of ischemic stroke, intracerebroventricular administration of human recombinant hepatocyte growth factor (HGF) mitigated motor impairment and cortical infarction. Recombinant HGF reduced MCAo-induced TNFα and IL1ß expression, and alleviated perilesional reactivation of microglia and astrocyte. All of the aforementioned beneficial effects of HGF were antagonized by an inhibitor to the type II transmembrane serine protease matriptase (MTP). MCAo upregulated MTP mRNA and protein in the lesioned cortex. MTP protein, not the mRNA, was increased further by recombinant HGF but reduced when MTP inhibitor (MTPi) was added to the treatment. Changes of the endogenous active HGF by MCAo, HGF or MTPi paralleled with the changes of MTP protein under the same conditions whilst neither HGF mRNA nor the total endogenous HGF protein were altered. These data showed that the therapeutic effects of HGF in stroke brain is attributed to its proteolytic activation and that MTP is a main protease of the event. MCAo enhanced MTP mRNA and thus protein expression; the initial use of the recombinant active HGF stabilized MCAo-induced MTP protein and subsequent activation of endogenous latent HGF which in turn stabilized further MTP protein. A reciprocal regulation between MTP and HGF appears to be present where MTP promotes HGF activation and the active HGF prevents MTP protein turnover. This study, for the first time, shows that MTP can participate in neural protection in stroke brain through activation of HGF. The cycles of HGF-MTP regulation achieved preservation of the neurological activity.


Asunto(s)
Factor de Crecimiento de Hepatocito , Accidente Cerebrovascular , Animales , Encéfalo/metabolismo , Factor de Crecimiento de Hepatocito/genética , Factor de Crecimiento de Hepatocito/metabolismo , Humanos , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/metabolismo , Neuroprotección , ARN Mensajero/metabolismo , Ratas , Serina Endopeptidasas , Serina Proteasas/metabolismo , Accidente Cerebrovascular/metabolismo
8.
Chin J Traumatol ; 26(4): 236-243, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36635154

RESUMEN

Blunt bowel injury (BBI) is relatively rare but life-threatening when delayed in surgical repair or anastomosis. Providing enteral nutrition (EN) in BBI patients with open abdomen after damage control surgery is challenging, especially for those with discontinuity of the bowel. Here, we report a 47-year-old male driver who was involved in a motor vehicle collision and developed ascites on post-trauma day 3. Emergency exploratory laparotomy at a local hospital revealed a complete rupture of the jejunum and then primary anastomosis was performed. Postoperatively, the patient was transferred to our trauma center for septic shock and hyperbilirubinemia. Following salvage resuscitation, damage control laparotomy with open abdomen was performed for abdominal sepsis, and a temporary double enterostomy (TDE) was created where the anastomosis was ruptured. Given the TDE and high risk of malnutrition, multiple portions EN were performed, including a proximal portion EN support through a nasogastric tube and a distal portion EN via a jejunal feeding tube. Besides, chyme delivered from the proximal portion of TDE was injected into the distal portion of TDE via a jejunal feeding tube. Hyperbilirubinemia was alleviated with the increase in chyme reinfusion. After 6 months of home EN and chyme reinfusion, the patient finally underwent TDE reversal and abdominal wall reconstruction and was discharged with a regular diet. For BBI patients with postoperative hyperbilirubinemia who underwent open abdomen, the combination of multiple portions EN and chyme reinfusion may be a feasible and safe option.


Asunto(s)
Traumatismos Abdominales , Enfermedades Intestinales , Masculino , Humanos , Persona de Mediana Edad , Nutrición Enteral , Intestinos/cirugía , Abdomen/cirugía , Anastomosis Quirúrgica , Traumatismos Abdominales/complicaciones , Traumatismos Abdominales/cirugía
9.
Hu Li Za Zhi ; 70(2): 46-57, 2023 Apr.
Artículo en Zh | MEDLINE | ID: mdl-38532674

RESUMEN

BACKGROUND: There is growing concern related to the recent rise in consumption of cigarettes, electronic cigarettes, and heated tobacco products. The government should pay more attention to the use of various tobacco products by university students. PURPOSE: Problem behavior theory was used in this study to explore the factors influencing the use of various tobacco products by university students in the Greater Taipei area. METHODS: In this cross-sectional study, convenience sampling was used to select eight institutions of higher education in the Greater Taipei area. Eight departments recognized by the Ministry of Education were then listed on a table for use in randomizing the selection of third- and fourth-year undergraduate students. A total of 115 participants filled out the questionnaires included in the self-administered online survey. Data analysis was conducted using logistic regression. RESULTS: The prevalence of tobacco-product use in the sample was 5.22%. Logistic regression analysis revealed having parents who smoked (adjusted odds ratio, AOR = 2.05), holding a positive attitude toward their parents' smoking (AOR = 4.23), having peers who smoked (AOR = 4.33), engaging in deviant behavior (AOR = 90.44), and having peers involved in deviant behavior (AOR = 103.99) to be associated with a higher likelihood of engaging in tobacco-product use. CONCLUSIONS / IMPLICATIONS FOR PRACTICE: Family, peers and delinquency significantly influence the usage behavior of university students with regard to tobacco products. The government should allocate greater resources for tobacco harm prevention education aimed at the parents of university students. In addition, integrating tobacco harm education into campus curricula, utilizing social media for online digital education, and providing students with counseling and support measures are strategies that may help reduce the tobacco-product use among this vulnerable population.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Problema de Conducta , Productos de Tabaco , Humanos , Universidades , Estudios Transversales , Estudiantes/psicología
10.
Phys Rev Lett ; 129(14): 148102, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36240397

RESUMEN

We experimentally demonstrate the two-stage structural and slowing-down percolating transitions, followed by the confluent transition in the densifying cancer cell monolayers from the dilute state, and investigate their impacts on collective cell dynamics. It is found that cells aggregate into clusters at low cell density. With increasing cell number density, the structural percolation through the formation of a large cell cluster percolating through the space precedes the dynamical percolation transition of forming a percolating cluster of slow cell elements. Both percolating transitions exhibit scale-free scaling behaviors of cluster size distributions and fractal structures, similar to those of the universality class of 2D nonequilibrium systems governed by percolation theory. Dynamically, at low cell density, cell aggregation enhances cooperative motion. The structural percolation leads to slower motion, especially with stronger suppression for the high-frequency modes in the turbulent-like velocity power spectra. The following slowing-down percolation associated with the onset of cell crowding in regions occupied by cells further enhances dynamical slowing-down, and suppresses the increasing trend of dynamical heterogeneity and the steepening of the power spectrum of motion, until their reversions after the confluent transition.


Asunto(s)
Fractales , Neoplasias , Agregación Celular
11.
Eur Phys J E Soft Matter ; 45(11): 89, 2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36346482

RESUMEN

Using time-lapse phase contrast microscopy, the formation and closure of spontaneously generated voids in the densifying monolayers of isotropic epithelial cells (ECs) and elongated fibroblast cells (FCs) through proliferation from the sub-confluent state are investigated. It is found that, in both types of monolayers after forming a connected network composed of nematic patches with different orientations, numerous multi-scale voids can be spontaneously formed and gradually close with increasing time. The isotropic fluctuations of deformation and crawling of ECs and the anisotropic axial motion/alignment polarizations of FCs are the two keys leading to the following different generic dynamical behaviors. In EC monolayers, voids exhibit irregular boundary fluctuations and easier cell re-orientation of front layer cells (FLCs) surrounding void boundaries. Void closures are mainly through pinching the gap between the opposite fluctuating void boundaries, and the inward crawling of FLCs to reduce void area associated with topological rearrangement to reduce FLC number. In FC monolayers, large voids have piecewise smooth convex boundaries, and cusp-shaped concave boundaries with cells orienting toward the void at cusp tips. The extension of a thin cell bridge from the cusp tip can bisect a large void into smaller voids. For smaller FC voids dominated by convex boundaries, along which cell alignment prohibits inward crawling, the reduction of FLC number through successive outward squeezing of single FLCs by neighboring FLCs sliding along the void boundary plays an important role for topological rearrangement and void closure. Unlike those surrounding artificial wounds in dense EC monolayers, the absence of ring-like purse-strings surrounding EC and FC voids allows topological rearrangements for reducing void perimeter and void area.


Asunto(s)
Fibroblastos
12.
Molecules ; 27(9)2022 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-35566177

RESUMEN

Plant of the genus Zingiber (Zingiberaceae) have primarily distributed in subtropical and tropical Asia, South America and Africa. The species of this genus have been widely used as food and in folk with a long history for treating various diseases. Reports related to the phytochemistry and phytochemistry of Zingiber species are numerous, but articles on the summary of the genus Zingiber remain scarce. This review aims at presenting comprehensive information about the genus Zingiber and providing a reference for the future application by systematically reviewing the literature from 1981 to 2020. Currently, a total of 447 phytochemical constituents have been isolated and identified from this genus, in which volatile oils, diarylheptanoids, gingerols, flavonoids and terpenoids are the major components. Gingerols, which are the main functional components, are the spicy and aromatic ingredients in the Zingiber species. Extracts and single compounds from Zingiber plants have been discovered to possess numerous biological functions, such as anti-inflammatory, anticancer, antimicrobial, larvicidal, antioxidant and hypoglycemic activities. This review provides new insights into the ethnomedicine, phytochemistry and pharmacology of the genus Zingiber and brings to the forefront key findings on the functional components of this genus in food and pharmaceutical industries.


Asunto(s)
Medicina Tradicional , Zingiberaceae , Etnofarmacología , Fitoquímicos/química , Fitoterapia , Extractos Vegetales/química , Extractos Vegetales/farmacología , Zingiberaceae/química
13.
Molecules ; 27(9)2022 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-35566214

RESUMEN

In recent years, synthetic antioxidants that are widely used in foods have been shown to cause detrimental health effects, and there has been growing interest in antioxidants realised from natural plant extracts. In this study, we investigate the potential effects of natural antioxidant components extracted from the forage plant marigold on the oxidative stability of soybean oil. First, HPLC-Q-TOF-MS/MS was used with 1,1-diphenyl-2-picrylhydrazyl (DPPH) to screen and identify potential antioxidant components in marigold. Four main antioxidant components were identified, including quercetagetin-7-O-glucoside (1), quercetagetin (2), quercetin (3) and patuletin (4). Among them, quercetagetin (QG) exhibited the highest content and the strongest DPPH radical scavenging activity and effectively inhibited the production of oxidation products in soybean oil during accelerated oxidation, as indicated by reductions in the peroxide value (PV) and acid value (AV). Then, the fatty acids and volatile compounds of soybean oil were determined with gas chromatography-mass spectrometry (GC-MS) and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). A total of 108 volatile components, including 16 alcohols, 23 aldehydes, 25 ketones, 4 acids, 15 esters, 18 hydrocarbons, and 7 other compounds, were identified. QG significantly reduced the content and number of aldehydes and ketones, whereas the formation of acids and hydrocarbons was completely prevented. In addition, the fatty acid analysis demonstrated that QG significantly inhibited oxidation of unsaturated fatty acids. Consequently, QG was identified as a potential, new natural antioxidant that is believed to be safe, effective and economical, and it may have potential for use in plant extracts feed additives.


Asunto(s)
Calendula , Tagetes , Aldehídos , Antioxidantes/química , Cetonas , Estrés Oxidativo , Extractos Vegetales/química , Extractos Vegetales/farmacología , Aceite de Soja/análisis , Tagetes/química , Espectrometría de Masas en Tándem
14.
Angew Chem Int Ed Engl ; 61(31): e202204319, 2022 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-35596681

RESUMEN

Disclosed here is the first geminal (gem-) hydroborative cyclization of enynes. Different from known hydroborative cyclizations, this process adds hydrogen and boron to the same position, leading to a new reaction mode. With [Cp*RuCl]4 as catalyst, a range of gem-hydroborated bicyclic products bearing a cyclopropane unit could be rapidly assembled from simple enyne substrates. Control experiments and density functional theory (DFT) calculations provided important insights into the reaction mechanism. Notably, two major competing pathways may operate with substrate-dependence. 1,6-Enynes favor initial oxidative cyclometalation to form a ruthenacyclopentene intermediate prior to engaging hydroborane, while other enynes (e.g., 1,7-enynes) that lack strong propensity toward cyclization prefer initial alkyne gem-(H,B)-addition to form an α-boryl ruthenium carbene followed by intramolecular olefin cyclopropanation. This process also represents the first ruthenium-catalyzed enyne hydroborative cyclization.


Asunto(s)
Rutenio , Alquenos , Alquinos/química , Catálisis , Ciclización , Rutenio/química
15.
Mol Imaging ; 2021: 9305277, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35936114

RESUMEN

Hepatocellular carcinoma (HCC) is a notoriously difficult cancer to treat. The recent development of immune checkpoint inhibitors has revolutionised HCC therapy; however, successful response is only observed in a small percentage of patients. Biomarkers typically used to predict treatment response in other tumour types are ineffective in HCC, which arises in an immune-suppressive environment. However, imaging markers that measure changes in tumour infiltrating immune cells may supply information that can be used to determine which patients are responding to therapy posttreatment. We have evaluated [18F]AlF-mNOTA-GZP, a radiolabeled peptide targeting granzyme B, to stratify response to ICIs in a HEPA 1-tumours, a syngeneic model of HCC. Posttherapy, in vivo tumour retention of [18F]AlF-mNOTA-GZP was correlated to changes in tumour volume and tumour-infiltrating immune cells. [18F]AlF-mNOTA-GZP successfully stratified response to immune checkpoint inhibition in the syngeneic HEPA 1-6 model. FACS indicated significant changes in the immune environment including a decrease in immune suppressive CD4+ T regulatory cells and increases in tumour-associated GZB+ NK+ cells, which correlated well with tumour radiopharmaceutical uptake. While the immune response to ICI therapies differs in HCC compared to many other cancers, [18F]AlF-mNOTA-GZP retention is able to stratify response to ICI therapy associated with tumour infiltrating GZB+ NK+ cells in this complex tumour microenvironment.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/patología , Granzimas/uso terapéutico , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Tomografía de Emisión de Positrones , Microambiente Tumoral
16.
Bioorg Med Chem Lett ; 48: 128263, 2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34271072

RESUMEN

The COVID-19 pandemic caused by SARS-CoV-2 has created an unprecedented global health emergency. As of July 2021, only three antiviral therapies have been approved by the FDA for treating infected patients, highlighting the urgent need for more antiviral drugs. The SARS-CoV-2 3CL protease (3CLpro) is deemed an attractive drug target due to its essential role in viral polyprotein processing and pathogenesis. Indeed, a number of peptidomimetic 3CLpro inhibitors armed with electrophilic warheads have been reported by various research groups that can potentially be developed for treating COVID-19. However, it is currently impossible to compare their relative potencies due to the different assays employed. To solve this, we conducted a head-to-head comparison of fifteen reported peptidomimetic inhibitors in a standard FRET-based SARS-CoV-2 3CLpro inhibition assay to compare and identify potent inhibitors for development. Inhibitor design and the suitability of various warheads are also discussed.


Asunto(s)
Antivirales/química , Proteasas 3C de Coronavirus/antagonistas & inhibidores , Inhibidores de Cisteína Proteinasa/química , Peptidomiméticos/química , SARS-CoV-2/enzimología , Antivirales/metabolismo , Proteasas 3C de Coronavirus/metabolismo , Inhibidores de Cisteína Proteinasa/metabolismo , Pruebas de Enzimas , Transferencia Resonante de Energía de Fluorescencia , Concentración 50 Inhibidora , Peptidomiméticos/metabolismo , Unión Proteica
17.
Molecules ; 26(13)2021 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-34202643

RESUMEN

Bopu powder® and Sangrovit® were developed from Macleayacordata and are widely used in agriculture and animal husbandry, but their impurities have been rarely reported in the literature. Impurity analysis is of great importance to the quality and safety of veterinary drugs. In this study, high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS) combined with a screening method was used to screen and characterize the impurities in Bopu powder® and Sangrovit®. A total of 58 impurities were screened from Bopu powder® and Sangrovit® using the screening strategies, of which 39 were identified by their accurate m/z value, characteristic MS/MS data, and fragmentation pathways of references. This established method was used for impurity analysis for the first time and proved to be a useful and rapid tool to screen and identify the impurities of Bopu powder® and Sangrovit®, especially for those at trace levels in a complex sample. In addition, this study marks the first comprehensive research into impurities in these two products and has great significance for the systematic detection of impurities in other plant-derived drugs.


Asunto(s)
Contaminación de Medicamentos , Medicamentos Herbarios Chinos/análisis , Cromatografía Líquida de Alta Presión , Polvos , Espectrometría de Masa por Ionización de Electrospray
18.
BMC Plant Biol ; 20(1): 410, 2020 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-32883206

RESUMEN

BACKGROUND: To fully elucidate the roles and mechanisms of plant hormones in leaf senescence, we adopted an integrated analysis of both non-senescing and senescing leaves from red maple with transcriptome and metabolome data. RESULTS: Transcription and metabolite profiles were generated through a combination of deep sequencing, third-generation sequencing data analysis, and ultrahigh-performance liquid chromatograph Q extractive mass spectrometry (UHPLC-QE-MS), respectively. We investigated the accumulation of compounds and the expression of biosynthesis and signaling genes for eight hormones. The results revealed that ethylene and abscisic acid concentrations increased during the leaf senescence process, while the contents of cytokinin, auxin, jasmonic acid, and salicylic acid continued to decrease. Correlation tests between the hormone content and transcriptional changes were analyzed, and in six pathways, genes closely linked with leaf senescence were identified. CONCLUSIONS: These results will enrich our understanding of the mechanisms of plant hormones that regulate leaf senescence in red maple, while establishing a foundation for the genetic modification of Acer in the future.


Asunto(s)
Acer/genética , Redes y Vías Metabólicas , Metaboloma , Reguladores del Crecimiento de las Plantas/metabolismo , Hojas de la Planta/crecimiento & desarrollo , Transcriptoma , Acer/crecimiento & desarrollo , Acer/metabolismo , Perfilación de la Expresión Génica , Redes y Vías Metabólicas/genética , Metabolómica , Reguladores del Crecimiento de las Plantas/genética , Hojas de la Planta/genética , Transcripción Genética
19.
J Nat Prod ; 83(7): 2112-2121, 2020 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-32614583

RESUMEN

The arylomycins are a class of natural product antibiotics that inhibit bacterial type I signal peptidase and are under development as therapeutics. Four classes of arylomycins are known, arylomycins A-D. Previously, we reported the synthesis and analysis of representatives of the A, B, and C classes and showed that their spectrum of activity has the potential to be much broader than originally assumed. Along with a comparison of the mechanism of acquired and innate resistance, this led us to suggest that the arylomycins are latent antibiotics, antibiotics that once possessed broad-spectrum activity, but which upon examination today, have only narrow spectrum activity due to prior selection for resistance in the course of the competition with other microorganisms that drove their evolution in the first place. Interestingly, actinocarbasin, the only identified member of the arylomycin D class, has been reported to have activity against MRSA. To confirm and understand this activity, several actinocarbasin derivatives were synthesized. We demonstrate that the previously reported structure of actinocarbasin is incorrect, identify what is likely the correct scaffold, confirm that scaffold has activity against MRSA, and determine the origin of this activity.


Asunto(s)
Antibacterianos/análisis , Antibacterianos/química , Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Análisis Espectral/métodos , Relación Estructura-Actividad
20.
Arch Toxicol ; 94(6): 2179-2206, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32367274

RESUMEN

The use of flavoring substances is an important element in the development of reduced-risk products for adult smokers to increase product acceptance and encourage switching from cigarettes. In a first step towards characterizing the sub-chronic inhalation toxicity of neat flavoring substances, a study was conducted using a mixture of the substances in a base solution of e-liquid, where the standard toxicological endpoints of the nebulized aerosols were supplemented with transcriptomics analysis. The flavor mixture was produced by grouping 178 flavors into 26 distinct chemical groups based on structural similarities and potential metabolic and biological effects. Flavoring substances predicted to show the highest toxicological effect from each group were selected as the flavor group representatives (FGR). Following Organization for Economic Cooperation and Development Testing Guideline 413, rats were exposed to three concentrations of the FGR mixture in an e-liquid composed of nicotine (23 µg/L), propylene glycol (1520 µg/L), and vegetable glycerin (1890 µg/L), while non-flavored and no-nicotine mixtures were included as references to identify potential additive or synergistic effects between nicotine and the flavoring substances. The results indicated that the inhalation of an e-liquid containing the mixture of FGRs caused very minimal local and systemic toxic effects. In particular, there were no remarkable clinical (in-life) observations in flavored e-liquid-exposed rats. The biological effects related to exposure to the mixture of neat FGRs were limited and mainly nicotine-mediated, including changes in hematological and blood chemistry parameters and organ weight. These results indicate no significant additive biological changes following inhalation exposure to the nebulized FGR mixture above the nicotine effects measured in this sub-chronic inhalation study. In a subsequent study, e-liquids with FGR mixtures will be aerosolized by thermal treatment and assessed for toxicity.


Asunto(s)
Cigarrillo Electrónico a Vapor/toxicidad , Sistemas Electrónicos de Liberación de Nicotina , Aromatizantes/toxicidad , Perfilación de la Expresión Génica , Hígado/efectos de los fármacos , Sistema Respiratorio/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Vapeo/efectos adversos , Animales , Biomarcadores/sangre , Seguridad de Productos para el Consumidor , Femenino , Exposición por Inhalación , Hígado/metabolismo , Hígado/patología , Masculino , Ratas Sprague-Dawley , Sistema Respiratorio/inmunología , Sistema Respiratorio/metabolismo , Sistema Respiratorio/patología , Medición de Riesgo , Factores de Tiempo , Pruebas de Toxicidad
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