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Despite the widespread utilizable value of 3-oxazolines, mild and efficient access to such a class of unique structures still remains, to date, a challenge. Herein, we present a [3 + 2] annulation strategy, guided by the retrosynthetic principle of [CO + CCN], that utilizes vinyl azides as the CCN module and aldehydes as the CO module. This approach enables the efficient construction of the 3-oxazoline framework with remarkable features, including operational simplicity, environmental friendliness, and high efficiency. Notably, it solely requires the addition of inexpensive and readily available N-hydroxyphthalimide (NHPI) and air oxygen to obtain the desired product. It also provides a new way to generate the hydroxyl radical, which is produced by the homolysis of peroxycarboxylic acid. In addition, control experiments, X-ray crystallographic analysis, high-resolution mass spectrometry (HRMS), and density functional theory (DFT) calculations afford evidence for the key intermediates (hydroxyl radical, carboxyl radical, imine radical, hydroxyl substituted amide derivatives), further confirming the path for realization of 3-oxazolines.
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Examination of bacteria/host cell interactions is important for understanding the aetiology of many infectious diseases. The colony forming unit (CFU) has been the standard for quantifying bacterial burden for the past century, however, this suffers from low sensitivity and is dependent on bacterial culturability in vitro. Our data demonstrate the discrepancy between the CFU and bacterial genome copy number in an osteomyelitis-relevant co-culture system and we confirm diagnosis and quantify bacterial load in clinical bone specimens. This study provides an improved workflow for the quantification of bacterial burden in such cases.
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Osteomielitis , Osteomielitis/microbiología , Humanos , Carga Bacteriana , Técnicas de Cocultivo , Recuento de Colonia Microbiana , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/clasificaciónRESUMEN
Staphylococcus aureus is a major causative pathogen of osteomyelitis. Intracellular infections of resident bone cells including osteocytes can persist despite gold-standard clinical intervention. The mechanisms by which intracellular S. aureus evades antibiotic therapy are unknown. In this study, we utilised an in vitro S. aureus infection model of human osteocytes to investigate whether antibiotic-mediated dysregulation of autophagy contributes to this phenomenon. Infected or non-infected osteocyte-like cells were exposed to combinations of rifampicin, vancomycin, and modulators of autophagy. Intracellular bacterial growth characteristics were assessed using colony-forming unit (CFU) analysis, viable bacterial DNA abundance, and the rate of escape into antibiotic-free medium, together with measures of autophagic flux. Rifampicin, alone or in combination with vancomycin, caused a rapid decrease in the culturability of intracellular bacteria, concomitant with stable or increased absolute bacterial DNA levels. Both antibiotics significantly inhibited autophagic flux. However, modulation of autophagic flux did not affect viable bacterial DNA levels. In summary, autophagy was shown to be a factor in the host-pathogen relationship in this model, as its modulation affected the growth state of intracellular S. aureus with respect to both their culturability and propensity to escape the intracellular niche. While rifampicin and vancomycin treatments moderately suppressed autophagic flux acutely, this did not explain the paradoxical response of antibiotic treatment in decreasing S. aureus culturability whilst failing to clear bacterial DNA and hence intracellular bacterial load. Thus, off-target effects of rifampicin and vancomycin on autophagic flux in osteocyte-like cells could not explain the persistent S. aureus infection in these cells.
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Antibacterianos , Autofagia , Osteocitos , Rifampin , Infecciones Estafilocócicas , Staphylococcus aureus , Vancomicina , Autofagia/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/fisiología , Osteocitos/efectos de los fármacos , Osteocitos/microbiología , Antibacterianos/farmacología , Humanos , Vancomicina/farmacología , Rifampin/farmacología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Interacciones Huésped-Patógeno , ADN Bacteriano/genéticaRESUMEN
Selenosulfones, as pivotal pharmaceutical molecule frameworks, have become a research hotspot in modern organic synthesis due to their vital need for efficient preparation. Herein, we have developed an iron-catalyzed four-component controllable radical tandem reaction of allenes involving cycloketone oxime esters, 1,4-diazabicyclo[2.2.2]octane bis(sulfur dioxide) adduct (DABSO), and diphenyl diselenides for the synthesis of complex selenosulfones. This is the first case of achieving the 1,2-selenosulfonylation of allenes via a radical process, wherein precise control of radical rates and polarity matching enhance high regioselective conversion. The reaction conditions are ecofriendly and mild with step-efficiency by forming two new C-S bonds and one C-Se bond in one pot. Moreover, the 1,2-selenosulfonylation of allenes can be achieved by replacing cycloketone oxime esters with aryldiazonium tetrafluoroborates in this system.
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ETHNOPHARMACOLOGICAL RELEVANCE: Realgar (As2S2 or As4S4) is a traditional Chinese medicine (TCM) containing arsenic. Existing studies have shown that it has genotoxicity under long-term use with large doses. Niuhuang Jiedu (NHJD) is a Chinese medicine prescription containing realgar and seven other TCMs. Whether the multiple TCMs combination in NHJD can reduce the genotoxicity induced by realgar in equivalent doses is still unknown. AIM OF THE STUDY: To research the effect of NHJD on realgar's genotoxicity and the possible mechanism involved based on the arsenic methylation metabolic pathway. MATERIAL AND METHODS: Six groups (control, realgar (0.8 g/kg), NHJD (12.48 g/kg), as well as Glycyrrhiza uralensis Fisch (GU), Scutellaria baicalensis Georg (SB), Rheum palmatum L (RP) plus equivalent doses of realgar, respectively) were set up. ICR mice were intragastric administered for 12 weeks. First, genotoxicology tests were conducted to evaluate the effect of NHJD, GU, SB, and RP on reducing realgar's genotoxicity. The inorganic arsenic (iAs), dimethyl arsenic acid (DMA), and monomethyl arsenic acid (MMA) were determined by HPLC-AFS, and the iAs%, MMA%, DMA%, primary methylation index (PMI), etc. Were calculated. Meanwhile, the S-adenosyl methionine (SAM) and arsenate reductase (ARR) levels, the arsenic (+3)methyltransferase (As3MT), purine-nucleoside phosphorylase (PNP), glutathione S-transfer omega1 (GSTO1) gene expression were detected, aimed to explore the possible alleviation mechanisms of NHJD. RESULTS: The combination of multiple TCMs in NHJD decreased the levels of MN, SPA%, and DNA damage caused by realgar, with similar effects observed when SB, RP, and GU were used separately with realgar. Notably, the iAs% significantly decreased, while DMA% and PMI notably increased in the NHJD and realgar + SB (or RP) groups compared to the realgar-only group (P < 0.05). Increases in SAM and ARR levels were observed across various groups, but only the ARR increase in the NHJD group was statistically significant. Moreover, significant increases in As3MT mRNA and GSTO1 mRNA were noted in the NHJD group, and PNP mRNA levels significantly rose in the realgar + SB group. CONCLUSIONS: This study revealed that NHJD could attenuate the genotoxic effects of realgar. The botanicals SB, RP, and GU within NHJD may be key contributors to this effect. Enhancements in arsenic methylation capabilities through increased levels of SAM and ARR and elevated gene expressions of As3MT, PNP, and GSTO1 suggest potential mechanisms behind these findings.
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Arsenicales , Medicamentos Herbarios Chinos , Ratones Endogámicos ICR , Sulfuros , Animales , Medicamentos Herbarios Chinos/farmacología , Sulfuros/farmacología , Sulfuros/toxicidad , Masculino , Ratones , Daño del ADN/efectos de los fármacos , Mutágenos/toxicidad , Hígado/efectos de los fármacos , Hígado/metabolismo , Productos BiológicosRESUMEN
Pickering foam is a type of foam stabilized by solid particles known as Pickering stabilizers. These solid stabilizers adsorb at the liquid-gas interface, providing superior stability to the foam. Because of its high stability, controllability, versatility, and minimal environmental impact, nanomaterial-stabilized Pickering foam has opened up new possibilities and development prospects for foam applications. This review provides an overview of the current state of development of Pickering foam stabilized by a wide range of nanomaterials, including cellulose nanomaterials, chitin nanomaterials, silica nanoparticles, protein nanoparticles, clay mineral, carbon nanotubes, calcium carbonate nanoparticles, MXene, and graphene oxide nanosheets. Particularly, the preparation and surface modification methods of various nanoparticles, the fundamental properties of nanomaterial-stabilized Pickering foam, and the synergistic effects between nanoparticles and surfactants, functional polymers, and other additives are systematically introduced. In addition, the latest progress in the application of nanomaterial-stabilized Pickering foam in the oil industry, food industry, porous functional material, and foam flotation field is highlighted. Finally, the future prospects of nanomaterial-stabilized Pickering foam in different fields, along with directions for further research and development directions, are outlined.
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20(S)-Protopanaxadiol (PPD) is one of the bioactive ingredients in ginseng and possesses neuroprotective properties. Brain-type creatine kinase (CK-BB) is an enzyme involved in brain energy homeostasis via the phosphocreatine-creatine kinase system. We previously identified PPD as directly bound to CK-BB and activated its activity in vitro. In this study, we explored the antidepressive effects of PPD that target CK-BB. First, we conducted time course studies on brain CK-BB, behaviors, and hippocampal structural plasticity responses to corticosterone (CORT) administration. Five weeks of CORT injection reduced CK-BB activity and protein levels and induced depression-like behaviors and hippocampal structural plasticity impairment. Next, a CK inhibitor and an adeno-associated virus-targeting CKB were used to diminish CK-BB activity or its expression in the brain. The loss of CK-BB in the brain led to depressive behaviors and morphological damage to spines in the hippocampus. Then, a polyclonal antibody against PPD was used to determine the distribution of PPD in the brain tissues. PPD was detected in the hippocampus and cortex and observed in astrocytes, neurons, and vascular endotheliocytes. Finally, different PPD doses were used in the chronic CORT-induced depression model. Treatment with a high dose of PPD significantly increased the activity and expression of CK-BB after long-term CORT injection. In addition, PPD alleviated the damage to depressive-like behaviors and structural plasticity induced by repeated CORT injection. Overall, our study revealed the critical role of CK-BB in mediating structural plasticity in CORT-induced depression and identified CK-BB as a therapeutic target for PPD, allowing us to treat stress-related mood disorders.
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Antidepresivos , Corticosterona , Forma BB de la Creatina-Quinasa , Depresión , Sapogeninas , Animales , Humanos , Masculino , Ratones , Ratas , Antidepresivos/farmacología , Antidepresivos/administración & dosificación , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Forma BB de la Creatina-Quinasa/metabolismo , Forma BB de la Creatina-Quinasa/genética , Depresión/inducido químicamente , Depresión/tratamiento farmacológico , Modelos Animales de Enfermedad , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Ratones Endogámicos C57BL , Panax/química , Extractos Vegetales/farmacología , Extractos Vegetales/administración & dosificación , Ratas Sprague-Dawley , Sapogeninas/farmacologíaRESUMEN
Seamless phase 2/3 design has become increasingly popular in clinical trials with a single endpoint. Trials that define success based on the achievement of all co-primary endpoints (CPEs) encounter the challenge of inflated type 2 error rates, often leading to an overly large sample size. To tackle this challenge, we introduced a seamless phase 2/3 design strategy that employs Bayesian predictive power (BPP) for futility monitoring and sample size re-estimation at interim analysis. The correlations among multiple CPEs are incorporated using a Dirichlet-multinomial distribution. An alternative approach based on conditional power (CP) was also discussed for comparison. A seamless phase 2/3 vaccine trial employing four binary endpoints under the non-inferior hypothesis serves as an example. Our results spotlight that, in scenarios with relatively small phase 2 sample sizes (e.g., 50 or 100 subjects), the BPP approach either outperforms or matches the CP approach in terms of overall power. Particularly, with n1 = 50 and ρ = 0, BPP showcases an overall power advantage over CP by as much as 8.54%. Furthermore, when the phase 2 stage enrolled more subjects (e.g., 150 or 200), especially with a phase 2 sample size of 200 and ρ = 0, the BPP approach evidences a peak difference of 5.76% in early stop probability over the CP approach, emphasizing its better efficiency in terminating futile trials. It's noteworthy that both BPP and CP methodologies maintained type 1 error rates under 2.5%. In conclusion, the integration of the Dirichlet-Multinominal model with the BPP approach offers improvement in certain scenarios over the CP approach for seamless phase 2/3 trials with multiple CPEs.
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Inutilidad Médica , Proyectos de Investigación , Humanos , Teorema de Bayes , Tamaño de la Muestra , ProbabilidadRESUMEN
Traditional Chinese medicine (TCM) databases play a vital role in bridging the gap between TCM and modern medicine, as well as in promoting the popularity of TCM. Elucidating the bioactive ingredients of Chinese medicinal materials is key to TCM modernization and new drug discovery. However, one drawback of current TCM databases is the lack of quantitative data on the constituents of Chinese medicinal materials. Herein, we present ccTCM, a web-based platform designed to provide a component and compound-content-based resource on TCM and analysis services for medical experts. In terms of design features, ccTCM combines resource distribution, similarity analysis, and molecular-mechanism analysis to accelerate the discovery of bioactive ingredients in TCM. ccTCM contains 273 Chinese medicinal materials commonly used in clinical settings, covering 29 functional classifications. By searching and comparing, we finally adopted 2043 studies, from which we collected the compounds contained in each TCM with content greater than 0.001 %, and a total of 1449 were extracted. Subsequently, we collected 40,767 compound-target pairs by integrating multiple databases. Taken together, ccTCM is a versatile platform that can be used by TCM scientists to perform scientific and clinical TCM studies based on quantified ingredients of Chinese medicinal materials. ccTCM is freely accessible at http://www.cctcm.org.cn.