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The therapeutic application of biofunctional proteins relies on their intracellular delivery, which is hindered by poor cellular uptake and transport from endosomes to cytoplasm. Herein, we constructed a two-dimensional (2D) ultrathin layered double hydroxide (LDH) nanosheet for the intracellular delivery of a cell-impermeable protein, gelonin, towards efficient and specific cancer treatment. The LDH nanosheet was synthesized via a facile method without using exfoliation agents and showed a high loading capacity of proteins (up to 182%). Using 2D and 3D 4T1 breast cancer cell models, LDH-gelonin demonstrated significantly higher cellular uptake efficiency, favorable endosome escape ability, and deep tumor penetration performance, leading to a higher anticancer efficiency, in comparison to free gelonin. This work provides a promising strategy and a generalized nanoplatform to efficiently deliver biofunctional proteins to unlock their therapeutic potential for cancer treatment.
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Neuroinflammation is believed to be a critical process involved in the pathophysiology of Alzheimer's disease (AD). In this study, we investigated the pharmacological ability of OAB-14, a small molecule compound derived from bexarotene, to reduce neuroinflammation and improve cognitive decline in an AD mouse model (in vivo) and its ability to regulate signaling pathways implicated in neuroinflammation in vitro. It was found that OAB-14 significantly improved the cognitive function of 11-month-old AD mice (APP/PS1 transgenic mice) in a dose-dependent manner. Simultaneously, OAB-14 dramatically inhibited the activation of microglia in the cerebral cortex and hippocampus of AD mice and dose-dependently downregulated the expression of nuclear factor kappa B (NF-κB) and NOD-like receptor protein 3 (NLRP3) in the cerebral cortex. At the cellular level, OAB-14 reversed the downregulation of M2 phenotypic markers, including mannose receptor C-type 1 (MRC1) and arginase 1 (ARG1), in lipopolysaccharide (LPS)- or amyloid-ß protein oligomer (oAß1-42)-activated BV2 microglial cells and partially restored their ability to clear Aß. However, these effects were suppressed when peroxisome proliferator-activated receptor-γ (PPAR-γ) was specifically inhibited by GW9662, a selective PPAR-γ antagonist. These results suggested that OAB-14 could regulate microglial polarization by regulating PPAR-γ signaling, thereby mitigating neuroinflammation and improving cognitive function in AD mice.
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Three new compounds, apocimycin A-C, were identified from a saltern-derived Micromonospora sp. strain FXY415, isolated from Dongshi saltern, Fujian, China. Their planar structures and relative configuration were confirmed mainly by analysis of 1D- and 2D- NMR spectra. Three compounds belong to 4,6,8-trimythyl nona-2,7-dienoic acid derivatives, apocimycin A also has a phenoxazine nucleus. Apocimycin A-C exhibited weak cytotoxic and antimicrobial activities. Our research showed again that microbial communities in extreme environments are a potential resource in looking for new and bioactive led compounds.
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As a ubiquitous signal molecule in biosystems, nitric oxide (NO) plays an important role in many physiological and pathological processes. Therefore, it is of great significance to detect NO in organisms for the study of related diseases. Currently, a variety of NO fluorescent probes have been developed based on several types of reaction mechanisms. However, due to the inherent disadvantages of these reactions, like potential interference by biologically related species, there is a great need to develop NO probes based on the new reactions. Herein, we report our discovery of the unprecedented reaction between a widely used fluorophore of 4-(dicyanomethylene)-2-methyl-6-(p-(dimethylamino)styryl)-4H-pyran (DCM) and NO under mild conditions with fluorescence changes. By the analysis of the structure of the product, we proved that DCM undergoes a particular nitration process and proposed a mechanism for fluorescence changes due to the interruption of the intramolecular charge transfer (ICT) process of DCM by the nitrated product of DCM-NO2. Based on the understanding of this specific reaction, we then easily constructed our lysosomal-localized NO fluorescent probe LysoNO-DCM by linking DCM and a morpholine group, a lysosomal-targeting functional group. LysoNO-DCM exhibits excellent selectivity, sensitivity, pH stability, and outstanding lysosome localization ability with Pearson's colocalization coefficient of up to 0.92 and is successfully applied to the imaging of exogenous and endogenous NO in cells and zebrafish. Our studies expand design methods for NO fluorescence probes based on the novel reaction mechanism and will benefit the studies of this signaling molecule.
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Colorantes Fluorescentes , Óxido Nítrico , Animales , Óxido Nítrico/análisis , Concentración de Iones de Hidrógeno , Colorantes Fluorescentes/química , Pez Cebra , Lisosomas/químicaRESUMEN
In recent years, it has been proposed that G9a/EZH2 dual inhibition is a promising cancer treatment strategy. Herein, we present the discovery of G9a/EZH2 dual inhibitors that merge the pharmacophores of G9a and EZH2 inhibitors. Among them, the most promising compound 15h displayed potent inhibitory activities against G9a (IC50 = 2.90 ± 0.05 nM) and EZH2 (IC50 = 4.35 ± 0.02 nM), superior antiproliferative profiles against RD (CC50 = 19.63 ± 0.18 µM) and SW982 (CC50 = 19.91 ± 0.50 µM) cell lines. In vivo, 15h achieved significant antitumor efficacy in a xenograft mouse model of human rhabdoid tumor with a tumor growth inhibitory rate of 86.6% without causing observable toxic effects. The on-target activity assays illustrated that compound 15h can inhibit tumor growth by specifically inhibiting EZH2 and G9a. Therefore, 15h is a potential anticancer drug candidate for the treatment of malignant rhabdoid tumor.
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Antineoplásicos , Tumor Rabdoide , Humanos , Ratones , Animales , Tumor Rabdoide/tratamiento farmacológico , Lisina/farmacología , N-Metiltransferasa de Histona-Lisina , Inhibidores Enzimáticos/farmacología , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular , Proteína Potenciadora del Homólogo Zeste 2RESUMEN
Various studies were performed on the intermolecular interactions of daunorubicin (DNR) and cytarabine (Ara-C) co-loaded liposome to predict and elucidate its stability and in vitro drug release behavior. Langmuir monolayer and spectroscopy studies showed interactions between its components. The Langmuir monolayer study and blank liposomes stability study illustrated that interactions between lipids could affect their stability, and the DSPC/DSPG/Chol (7/2/1, mol%) mixed system tended to be thermodynamically and physicochemically stable. The interactions between daunorubicin and copper ions were then investigated by ultraviolet-visible (UV-vis) electronic absorption spectroscopy and circular dichroism (CD) spectroscopy, which revealed that the DNR-Cu complex was composed of daunorubicin and copper ions at a molar ratio of 1:1 or 1:2, and its solubility was related to the acidity of the solution. In vitro release experiment of liposomes with different copper gluconate contents illustrated that the interactions between drugs and copper ions were conducive to the retention and synergetic release of drugs. The stability and release studies of the DSPC/DSPG/Chol (7/2/1, mol%) co-loaded liposome illustrated that it had good storage and plasma stability, and the release behaviors of drugs were pH-related, i.e., drugs could be released faster under acidic condition. These studies indicated that intermolecular interactions could affect the stability and release behavior of the liposome, and a certain ratio of components could be conducive to its stability and synergistic release of drugs.
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Citarabina , Daunorrubicina , Liposomas , Cobre , Daunorrubicina/química , Liberación de Fármacos , Estabilidad de Medicamentos , Liposomas/químicaRESUMEN
Soluble epoxide hydrolase (sEH) is related to arachidonic acid cascade and is over-expressed in a variety of diseases, making sEH an attractive target for the treatment of pain as well as inflammatory-related diseases. A new series of memantyl urea derivatives as potent sEH inhibitors was obtained using our previous reported compound 4 as lead compound. A preferential modification of piperidinyl to 3-carbamoyl piperidinyl was identified for this series via structure-based rational drug design. Compound A20 exhibited moderate percentage plasma protein binding (88.6%) and better metabolic stability in vitro. After oral administration, the bioavailability of A20 was 28.6%. Acute toxicity test showed that A20 was well tolerated and there was no adverse event encountered at dose of 6.0 g/kg. Inhibitor A20 also displayed robust analgesic effect in vivo and dose-dependently attenuated neuropathic pain in rat model induced by spared nerve injury, which was better than gabapentin and sEH inhibitor (±)-EC-5026. In one word, the oral administration of A20 significantly alleviated pain and improved the health status of the rats, demonstrating that A20 was a promising candidate to be further evaluated for the treatment of neuropathic pain.
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BACKGROUND: Relapsed childhood polymicrobial osteomyelitis associated with dermatophytosis has not been reported in the literature. CASE PRESENTATION: Here we report on a case of a 45-year-old man who had left tibial osteomyelitis for 29 years, accompanied by skin fungal infection of the ipsilateral heel for 20 years, and underwent a second operation due to recurrence of polymicrobial infection 6 years ago. The patient had a history of injury from a rusty object, which penetrated the anterior skin of the left tibia middle segment causing subsequent bone infection, but was asymptomatic after receiving treatments in 1983. The patient was physically normal until dermatophytosis occurred on the ipsilateral heel skin in 1998. The patient complained that the dermatophytosis was gradually getting worse, and the tibial wound site became itchy, red, and swollen. The left tibial infection resurged in May 2012, leading to the patient receiving debridement and antibiotic treatment. H&E and Gram-stained histology was performed on biopsy specimens of sequestrum and surrounding inflammatory tissue. Tissue culture and microbiology examination confirmed polymicrobial infection with Staphylococcus aureus (S. aureus) and Corynebacterium and a fungus. Additionally, the patient also received potassium permanganate for dermatophytosis when he was admitted into the hospital. CONCLUSIONS: Together with longitudinal follow-up of medical history, surgical findings, histopathological and microbiology culture evidence, we conclude that boyhood tibia polymicrobial osteomyelitis with S. aureus and Corynebacterium occurred in this patient, and the fungal activation of dermatophytosis may have led to osteomyelitis relapse.
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Coinfección , Osteomielitis , Infecciones Estafilocócicas , Tiña , Antibacterianos , Niño , Coinfección/complicaciones , Coinfección/diagnóstico , Desbridamiento , Humanos , Masculino , Persona de Mediana Edad , Osteomielitis/complicaciones , Osteomielitis/diagnóstico , Infecciones Estafilocócicas/complicaciones , Staphylococcus aureus , Tibia/cirugía , Tiña/complicacionesRESUMEN
The prevention and treatment of cardiovascular disease (CVD) are necessary to improve patient quality of life and to reduce the burden of medical and other social problems. Reducing the impact of CVD through environmental intervention was hailed as the most economical approach and research into such interventions is becoming key. The purpose of this article is to summarize the research topics and developments in the field of the built environment and CVD between 2000 and 2021 using scientometric analysis. In total, 1304 records retrieved from the Web of Science core database were analyzed using CiteSpace software, and the results were displayed using knowledge mapping. The number of publications and conferences relating to the built environment and CVD showed an upward trend over the study period, with the United States taking the lead. Physical activity and the food environment were used as mediators and entry points to map the relationship between the built environment and CVD. Walkability, residence characteristics, the food environment, and greenness were key research topics. Research shifted over the period to incorporate quantitative analyses of subjective feelings while focusing on decreasing sedentary behavior. Understanding the variability in the built environment is critical to improving the generalizability of the findings presented in the individual studies. Inter-disciplinary and multi-disciplinary research is conducive to innovation and ensuring the integration of real environmental elements. This study provides an overview and valuable guidance for researchers relating to how the built environment impacts CVD.
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Enfermedades Cardiovasculares , Entorno Construido , Enfermedades Cardiovasculares/prevención & control , Humanos , Calidad de Vida , Características de la Residencia , Conducta SedentariaRESUMEN
Human malignant melanoma exhibits imbalances in redox status, leading to activation of many redox-sensitive signaling pathways. APE/Ref-1 is a multifunctional protein that serves as a redox chaperone that regulates many nuclear transcription factors and is an important mechanism in cancer cell survival of oxidative stress. Previous studies showed that APE/Ref-1 is a potential druggable target for melanoma therapy. In this study, we synthesized a novel APE/Ref-1 inhibitor, bis-cinnamoyl-1,12-dodecamethylenediamine (2). In a xenograft mouse model, compound 2 treatment (5 mg/kg) significantly inhibited tumor growth compared to the control group, with no significant systemic toxicity observed. We further synthesized compound 2 analogs to determine the structure-activity relationship based on their anti-melanoma activities. Among those, 4-hydroxyphenyl derivative (11) exhibited potent anti-melanoma activities and improved water solubility compared to its parental compound 2. The IC50 of compound 11 was found to be less than 0.1 µM. Compared to other known APE/Ref-1 inhibitors, compound 11 exhibited increased potency in inhibiting melanoma proliferation. As determined by luciferase reporter analyses, compound 2 was shown to effectively inhibit H2O2-activated AP-1 transcription activities. Targeting APE/Ref-1-mediated signaling using pharmaceutical inhibitors is a novel and effective strategy for melanoma treatment with potentially high impact.
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Hominidae , Melanoma , Animales , Cinamatos/farmacología , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Hominidae/metabolismo , Humanos , Peróxido de Hidrógeno , Melanoma/tratamiento farmacológico , RatonesRESUMEN
Parkinson's disease (PD) is a common degenerative disease of the central nervous system among the elderly. Istradefylline, an FDA-approved adenosine A2A receptor antagonist (anti-PD drug), has good efficacy. However, it has been reported that the double bond of istradefylline is easily converted into cis-configuration when exposed to an indoor environment or direct light in a dilute solution. In order to find more stable adenosine A2A receptor antagonists with similar pharmacological efficacy to istradefylline, the compounds series I-1 (12 compounds) was designed by maintaining the xanthine skeleton of istradefylline unchanged and replacing the trans-double bond with thiazole or benzothiazole and other biologically active heterocyclic compounds. These compounds were synthesized via multi-step experiment and successfully confirmed through different characterization techniques for their ability to inhibit cAMP formation in A2A AR overexpressing cells. The thiazole derivative of istradefylline (Compound I-1-11, I-1-12) exhibited significant activity (IC50 = 16.74 ± 4.11 µM, 10.36 ± 3.09 µM), as compared to istradefylline (IC50 = 5.05 ± 1.32 µM). In addition, the molecular docking of benzothiazole derivatives I-1-11 and thiazole derivatives I-1-12 with higher inhibition rate were carried out and compared with istradefylline. The molecular docking results showed that I-1-11 and I-1-12 anchored in the same site as that of XAC (3REY) with predicted affinity binding energy -6.63 kcal/mol and - 6.75 kcal/mol, respectively. Validation through dynamics simulation also showed stable interactions, with fluctuations <3 Å and MM/GBSA energy <-20 kcal/mol. Hence, this study could provide a basis for the rational design of adenosine A2A receptor antagonists with better potency.
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Antagonistas del Receptor de Adenosina A2 , Enfermedad de Parkinson , Adenosina , Antagonistas del Receptor de Adenosina A2/farmacología , Anciano , Benzotiazoles/farmacología , Humanos , Simulación del Acoplamiento Molecular , Purinas , Receptor de Adenosina A2A , XantinasRESUMEN
Off-target toxicity remains a major limitation of current cancer therapy, necessitating an alternative precision approach to treat cancers. Herein, a tumor microenvironment (TME)-triggered anticancer strategy was developed by constructing an anti-alcoholism drug disulfiram (DSF)-loaded, Cu-doped zeolite imidazolate frameworks-8 (DSF-Cu/ZIF-8) nanoparticle followed by PEGylation (PEG-DSF-Cu/ZIF-8) to realize in situ generation of cytotoxic compounds specifically in TME. The PEG-DSF-Cu/ZIF-8 demonstrated excellent hydrolytic stability in normal physiological conditions, guaranteeing the minimized off-target release of disulfiram and Cu ions. Under the TME condition, the PEG-DSF-Cu/ZIF-8 exhibited acidity-triggered biodegradation and the associated payload release, through which low-toxic compounds (disulfiram and Cu2+ ions) were converted to highly cytotoxic Cu-chelate product to kill cells specifically in TME. Tumor-sensitive anti-cancer performance was further enhanced by hydroxyl radical generation via TME-responsive Fenton-like reactions catalyzed by Cu+ presenting in the PEG-DSF-Cu/ZIF-8 structure and Cu+ produced during formation of the chelate product. Anti-cancer therapeutic evaluation was performed in 2D 4T1 tumor cell culture and 3D 4T1 tumor spheroids, and demonstrated highly TME-responsive, low-dose induced anti-cancer effect. This proof-of-concept work provides a nanoparticle-based drug repurposing strategy by developing a tumor-sensitive anti-cancer agent for low-toxic and efficacious cancer therapy.
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Estructuras Metalorgánicas , Neoplasias , Línea Celular Tumoral , Cobre/química , Disulfiram/química , Disulfiram/farmacología , Estructuras Metalorgánicas/farmacología , Neoplasias/tratamiento farmacológico , Microambiente TumoralRESUMEN
In Alzheimer's disease (AD), damaged Aß clearance contributes to elevated levels of Aß that cause a series of cytotoxic cascade reactions. Thus, targeting Aß clearance has now been considered a valid therapeutic approach for AD. Cellular uptake and degradation are important mechanisms for Aß clearance, which are mainly performed by the endosomal-autophagic-lysosomal (EAL) pathway. Our previous study showed that OAB-14, a novel small molecule designed with bexarotene as the lead compound, treatment for 3 months significantly alleviated cognitive disorders and remarkably reduced the deposition of Aß without affecting its production in APP/PS1 transgenic mice. Here, we further revealed that enhancement of the EAL activity is one of the mechanisms that increases Aß clearance after OAB-14 administration for 3 months. OAB-14 facilitates receptor-mediated endocytosis and restores autophagy flux via the AMPK/mTOR pathway. Meanwhile, OAB-14 enhances the lysosomal activity, and reduced Aß accumulation in lysosomes was observed in OAB-14-treated AD mice. These results suggest that OAB-14 may promote Aß clearance in lysosomes by alleviating the EAL dysfunction in AD mice.
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Enfermedad de Alzheimer , Péptidos beta-Amiloides , Enfermedad de Alzheimer/tratamiento farmacológico , Precursor de Proteína beta-Amiloide/genética , Animales , Autofagia , Modelos Animales de Enfermedad , Lisosomas , Ratones , Ratones TransgénicosRESUMEN
Due to its double bond, istradefylline rapidly isomerizes to Z-istradefylline when exposed to normal daylight in dilute solution. To solve the poor photostability of the istradefylline solution, a series of istradefylline derivatives (in total 17 compounds, including II-1 and II-2 series) were designed and synthesized, and their biological activity in inhibiting cAMP was evaluated. The IC50 values of compounds II-1-3, II-2-1, II-2-2, II-2-3, II-2-4, and II-2-6 were 7.71, 6.52, 6.16, 7.23, 7.96, and 9.68 µg/mL, respectively, which had the same order of activity as that of istradefylline (IC50 value was 1.94 µg/mL). The preliminary structure-activity relationship suggested that the 6-amino in adenine played an important role in binding an A2A receptor. The results of photostability experiments showed that the photostability of the target compounds of II-1 and II-2 series was improved when compared with that of istradefylline.
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PURPOSE: Glimepiride, an FDA-approved oral hypoglycemic drug, is a long-acting sulfonylurea (SU), used for treating type 2 diabetes. The study aimed to evaluate the bioequivalence and safety profiles of two different formulations of glimepiride 1 mg from two different manufactures in healthy Chinese subjects in the fasting and fed state in order to acquire adequate pharmacokinetic evidence for registration approval of the test formulation. PATIENTS AND METHODS: This study is an open-label, two-period, two-sequence, randomized, two-way crossover pharmacokinetic study in healthy Chinese subjects in the fasting and fed state. Seventy-two subjects were randomly assigned to the fasting group and the fed group (n=36 each). We collected blood samples, 24-h post drug administration. The plasma concentration of glimepiride was assessed using HPLC coupled with mass spectrometry. The following parameters were evaluated: AUC0-inf, AUC0-last, Cmax, t1/2, Tmax, and λz. Safety was determined based on the occurrence of adverse events (AEs) and laboratory examinations (biochemistry, hematology, and urinalysis) throughout the entire study period. RESULTS: The geometric mean ratios (GMR) amongst the two glimepiride formulations for the primary pharmacokinetic parameters, ie, AUC0-inf, AUC0-last, and Cmax as well as the corresponding 90% CIs, were all within the range of 80.00-125.00% in the fasting and fed state. The safety profile for both treatments was comparable. CONCLUSION: PK analysis revealed that the test and reference formulations of glimepiride were bioequivalent and well tolerated in healthy Chinese subjects. Chinese Clinical Trials Registry identifier: CTR20171121. CLINICAL TRIAL REGISTRATION NUMBER: CTR20171121.
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Hipoglucemiantes/farmacocinética , Compuestos de Sulfonilurea/farmacocinética , Adolescente , Adulto , Pueblo Asiatico , Estudios Cruzados , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Composición de Medicamentos , Femenino , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/sangre , Masculino , Compuestos de Sulfonilurea/administración & dosificación , Compuestos de Sulfonilurea/sangre , Equivalencia Terapéutica , Adulto JovenRESUMEN
Istradefylline is a selective adenosine antagonist for the A2a receptor, and it is used to treat the Parkinson's disease and improve dyskinesia in the early stage of the Parkinson's disease. An impurity in the istradefylline intermediate A1 (6-amino-1,3-diethyl-2,4-(1H,3H)-pyrimidinedione) was identified by high performance liquid chromatography (HPLC); it was separated by preparative HPLC and further characterized by UV, IR, MS, NMR, 2D NMR and single-crystal XRD analyses. The impurity was identified as (E)-N-ethyl-2-cyano-3-ethylamino-2-butenamide, which originated from the synthetic process of the intermediate A1. The structure of this impurity might affect the efficiency and safety of istradefylline; therefore, the research and control of this impurity are necessary for ensuring the quality of istradefylline.
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Objective To determine the epidemiological, clinical and microbiological characteristics, of patients with post-traumatic osteomyelitis of extremity fractures, and provide evidence-based guidelines for early diagnosis and treatment, including empiric antibiotic therapy. Methods Human subject research was performed using institutional review board approved protocols. A retrospective chart review was conducted on 5,368 patients diagnosed with extremity traumatic fractures from January 1, 2012 to December 31, 2015, to identify osteomyelitis patients. Records from the Microbiology Department were reviewed, and patients with a positive wound culture, or bone biopsy culture, were selected for the study. Microbial suceptability was determined by the M-100-S22 protocol (Clinical & Laboratory Standards Institute® (CLSI) 2012 USA). Additional clinical information, including data on patients' baseline epidemiological, clinical, and microbiological records was collected from all available charts, and reviewed using a designed protocol. Results 84 (1.56%) patients were diagnosed with osteomyelitis based on a positive culture result. The most prevalent comorbidities in these patients were compartment syndrome, diabetes and hypertension. The most commonly involved infected site was the tibia-fibula (47.62%). 66 (78.57%) of these cases were monomicrobial, and 18 cases (21.43%) were polymicrobial. The infections were predominantly caused by Gram-positive bacteria (56, 53.85%). The most common Gram-positive bacteria were Staphylococcus aureus (39 cases, 37.50%) and S. epidermidis (6 cases, 5.77%), which were sensitive to ampicillin, synercid/ dalfopristin, linezolid, tigecycline, macrodantin, and vancomycin. S. aureus was the most common pathogen in both monomicrobial and polymicrobial cases. All 17 cases of MRSA infection were sensitive to Imezolid, ampicillin, synercid/ dalfopristin, linezolid, tigecycline, furadantin, piperacillin/yaz, rifampicin, and vancomycin, respectively. The most common Gram-negative bacteria were E. coli (16 cases, 15.38%) and Enterobacter cloacae (11 cases, 10.58%), which were sensitive to thienamycin. Conclusions In this study, the overall rate of post-traumatic osteomyelitis of limb fractures (1.56%) is lower than the national average rate (2.6-7.8%), for major medical centers in China. The main medical comorbidities were compartment syndrome, diabetes mellitus and hypertension. The most common infection was monomicrobial in lower extremities. S. aureus was the most common pathogen, which presented in 39 (37.50%) cases, and 17 of these (43.59%) were caused by MRSA. These findings can guide empiric antibiotic therapy in Southwest China for osteomyelitis in patients with traumatic limb fractures.
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A series of novel 11-[3-[(arylcarbamoyl)oxy]propylamino]-11-deoxy-6-O-methyl-3-oxoerythromycin A 11-N,12-O-cyclic carbamate derivatives (6a-h) were designed, synthesized and evaluated for their antibacterial activities in vitro. Most of these compounds had significant antibacterial activity against two groups of pathogens of Methicillin-sensitive Staphylococcus aureus (MIC50=0.031-2 µg ml-1) except 6g and Methicillin-sensitive S. epidermidis (MIC50=0.031-0.5 µg ml-1). MIC90 of 6d against Methicillin-resistant S. epidermidis was at least 16-fold better than that of erythromycin (EMA), azithromycin (AZM) and ABT-773. 6d and 6e had more potent antibacterial activity against S. pneumoniae than EMA, AZM and ABT-773. In particular, compounds 6d and 6e also showed relatively potent activity against Haemophilus influenzae and Streptococcus hemolyticus.
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Antibacterianos/síntesis química , Antibacterianos/farmacología , Carbamatos/química , Carbamatos/farmacología , Eritromicina/análogos & derivados , Azitromicina/farmacología , Eritromicina/síntesis química , Eritromicina/farmacología , Haemophilus influenzae/efectos de los fármacos , Cetólidos/farmacología , Resistencia a la Meticilina , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pyogenes/efectos de los fármacosRESUMEN
Aspertetranones A-D (1-4), four new highly oxygenated putative rearranged triketide-sesquiterpenoid meroterpenes, were isolated from the marine algal-associated fungus Aspergillus sp. ZL0-1b14. On the basis of a comprehensive spectroscopic analysis, the planar structures of aspertetranones were determined to possess an unusual skeleton in the terpenoid part. The relative and absolute configurations of the aspertetranones were assigned on the basis of NOESY analysis, X-ray crystallography, and circular dichroism spectroscopy. Compounds 1-4 were evaluated for anti-inflammatory activity in LPS-stimulated RAW264.7 macrophages. Aspertetranone D exhibited an inhibitory effect against IL-6 production with 69% inhibition at 40 µM.
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Aspergillus/química , Sesquiterpenos/aislamiento & purificación , Algoritmos , Animales , Antiinflamatorios/farmacología , China , Cristalografía por Rayos X , Interleucina-6/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Biología Marina , Ratones , Conformación Molecular , Estructura Molecular , Óxido Nítrico/análisis , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/farmacologíaRESUMEN
Osteosarcoma (OS), the most common malignant bone tumor, occurs mainly in adolescents and young adults, with a morbidity of â¼5 cases per million. The expression levels of microRNAs (miRNAs) as tumor suppressors were recently found to be downregulated in OS. Certain alterations of miRNAs and the possible mechanisms through which miRNAs affect cell proliferation and migration in OS were recently found to be correlated with methylation epigenetic mechanisms. In this study, it was demonstrated that, due to hypermethylation, the expression level of miRNA-142 (miR-142) was significantly downregulated in OS tissues and cells compared with that in control samples. The present study demonstrated an increased expression of miR-142 in Saos-2 and MG63 cells treated with demethylation agents, suggesting that the effect of such agents on cell growth, inhibition of invasion and cell cycle retardation may be mediated by miR-142 in OS.