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Despite being promising, the clinical application of magnetic hyperthermia for brain cancer treatment is limited by the requirement of highly invasive intracranial injections. To overcome this limitation, here we report the development of gallic acid-coated magnetic nanoclovers (GA-MNCs), which allow not only for noninvasive delivery of magnetic hyperthermia but also for targeted delivery of systemic chemotherapy to brain tumors. GA-MNCs are composed of clover-shaped MNCs in the core, which can induce magnetic heat in high efficiency, and polymerized GA on the shell, which enables tumor vessel-targeting. We demonstrate that intravenous administration of GA-MNCs following alternating magnetic field exposure effectively inhibited brain cancer development and preferentially disrupted tumor vasculature, making it possible to efficiently deliver systemic chemotherapy for further improved efficacy. Due to the noninvasive nature and high efficiency in killing tumor cells and enhancing systemic drug delivery, GA-MNCs have the potential to be translated for improved treatment of brain cancer.
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Neoplasias Encefálicas , Hipertermia Induzida , Nanopartículas de Magnetita , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Hipertermia , Fenômenos MagnéticosRESUMO
Ganoderma lucidum has been used as a rare medical mushroom for centuries in China, due to its health-promoting properties. Successive cropping obstacles are common in the cultivation of G. lucidum, although the remaining nutrients in the germ substrate are sufficient for a second fruiting. Here, we aimed to study the metabolite profile of G. lucidum via nontargeted metabonomic technology. Metabonomic data revealed that organic acids played an important role in the cropping obstacles of G. lucidum, which is accordance with the pH decrease in the germ substrate. A Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis indicated that most differential acids participated in the metabolic pathways. Five acids were all significantly upregulated by two MS with high energy (MSE) modes in two cultivars, among which 5-hydroxy-2-oxo-4-ureido-2,5-dihydro-1H-imidazole-5-carboxylic acid is also involved in purine metabolism regulation and microbial metabolism in diverse environments. Taken together, this work illustrated the organic acid stress generated by G. lucidum, which formed the autotoxicity feedback, and resulted in cropping obstacles. Determining the cause of the cropping obstacles in G. lucidum will promote the utilization rate of fungus substrate to realize the sustainable use of this resource.
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Ganoderma , Reishi , Ácidos Carboxílicos , Ganoderma/química , Imidazóis , Redes e Vias Metabólicas , Purinas , Reishi/genéticaRESUMO
Spinetoram (XDE-175-J/L), a new spinosyn-based insecticide, is one of the most widely used bio-pesticide worldwide and its registration for direct application on cauliflower to control Plutella xylostella is currently under review in China. In this study, an accredited method for simultaneous determination of spinetoram and its two metabolites in cauliflower was established and validated using QuEChERS (quick, easy, cheap, effective, rugged, and safe) preparation coupled with ultra-liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The average recoveries using this method were ranged from 74 to 99% with relative standard deviations (RSDs) of 2.4-10.5%. The dissipation kinetics and terminal residues of spinetoram and its two metabolites in cauliflower were studied in Tianjin and Guizhou over two years under open field conditions. The dissipation experiments revealed that spinetoram was swiftly degraded in cauliflower, with the half-lives less than or equal to 4.85 days. The terminal residues of total spinetoram (sum of spinetoram and its two metabolites) detected in cauliflower samples were in the range of 0.009 mg/kg-0.337 mg/kg. Dietary risk assessment study was implemented based on the scientific data of field trials, food consumption and acceptable daily intake (ADI). The estimated long-term dietary risk probability (RQ) of total spinetoram from cauliflower was between 5.79% and 5.91%, indicating that spinetoram was associated with acceptable risk for dietary cauliflower consumption. The results would provide scientific guidance for proper usage of spinetoram in cauliflower field ecosystem.
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Brassica/fisiologia , Inseticidas/toxicidade , Macrolídeos/toxicidade , China , Cromatografia Líquida/métodos , Dieta , Ecossistema , Inseticidas/análise , Cinética , Resíduos de Praguicidas/análise , Medição de Risco , Espectrometria de Massas em Tandem/métodosRESUMO
In this work, an in situ acylation combined with solid-phase microextraction coupled to gas chromatography and mass spectrometry method has been developed for simultaneously determining haloanisoles (2,4,6-trichloranisole, 2,4,6-tribromoanisole), and their direct precursors (2,4,6-trichlorophenol, 2,4,6-tribromophenol) and indirect precursors (2-chloropenol, 2,4-dichlorophenol, 2-bromophenol, 2,4-dibromophenol) in water. The key parameters for the solid-phase microextraction were determined by using Plackett-Burman screening and optimized by central composite optimization. Under optimal conditions, the eight compounds can be analyzed in a short time (33 min) with a strong linearity ranging from 2 to 200 ng/L (correlation coefficient greater than 0.996), showing good sensitivities with the limit of detection in a range of 0.23-0.91 ng/L and a limit of quantification of 0.77-3.03 ng/L, good repeatability (2.00-9.10%) and interday precision (1.67-11.3%). When environmental water samples were treated, the recoveries of target compounds were 75.5-127.3%, suggesting that the developed method could be applied in probing the origin of haloanisoles and monitoring halophenols and haloanisoles in natural waters at concentration levels of ng/L.
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Objective: With the rapid advancement of Chat Generative Pre-Trained Transformer (ChatGPT) in medical research, our study aimed to identify global trends and focal points in this domain. Method: All publications on ChatGPT in medical research were retrieved from the Web of Science Core Collection (WoSCC) by Clarivate Analytics from January 1, 2023, to January 31, 2024. The research trends and focal points were visualized and analyzed using VOSviewer and CiteSpace. Results: A total of 1,239 publications were collected and analyzed. The USA contributed the largest number of publications (458, 37.145%) with the highest total citation frequencies (2,461) and the largest H-index. Harvard University contributed the highest number of publications (33) among all full-time institutions. The Cureus Journal of Medical Science published the most ChatGPT-related research (127, 10.30%). Additionally, Wiwanitkit V contributed the majority of publications in this field (20). "Artificial Intelligence (AI) and Machine Learning (ML)," "Education and Training," "Healthcare Applications," and "Data Analysis and Technology" emerged as the primary clusters of keywords. These areas are predicted to remain hotspots in future research in this field. Conclusion: Overall, this study signifies the interdisciplinary nature of ChatGPT research in medicine, encompassing AI and ML technologies, education and training initiatives, diverse healthcare applications, and data analysis and technology advancements. These areas are expected to remain at the forefront of future research, driving continued innovation and progress in the field of ChatGPT in medical research.
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To evaluate demographic characteristics and distribution of pediatric supracondylar fractures (SCFs) at a tertiary hospital in South China. A retrospective observational study was conducted on children aged 15 years or younger with a diagnosis of SCFs during the period from January 2016 to December 2018. Patients' medical records and radiographs were retrospectively analyzed for age at the time of injury, sex, site and mechanism of traumatic injury. A total of 760 patients with 761 SCFs were reviewed (453 males, 59.6%, and 307 females, 40.4%). There were 748 extension-type fractures (98.3%) and 13 flexion-type fractures (1.7%). Associated injuries were identified in 30/760 (3.9%) patients: associated fracture ( n â =â 15; 2%), nerve injury ( n â =â 12; 1.6%), open fracture ( n â =â 2; 0.2%) and compartment syndrome ( n â =â 1; 0.1%). Age at the time of fracture has a bimodal pattern with a first peak around the age of 1 year and a second peak around the age of 4-5 years. The fractures occurred mostly around 11 a.m. and between 4 and 9 p.m. in the evening. Most fractures occurred at home (50.7%), and falling down (62.2%) was the most frequent mechanism of injury. SCFs occurred most frequently in children aged 1 and 4-5 years, and during daylight hours. In about 96% of cases, these were isolated injuries, and falling down was found to be the most frequent traumatic mechanism. Based on our findings, targeted educational efforts and interventions can be set up in order to prevent the occurrence of SCFs in South China. Level of evidence: III.
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Fraturas Expostas , Fraturas do Úmero , Masculino , Feminino , Criança , Humanos , Estudos Retrospectivos , China/epidemiologiaRESUMO
BACKGROUND: Hepatic cancer is a common cancer in clinical practice. Current drug therapies for this condition include targeted therapy, chemotherapy, and immunotherapy. Tumor lysis syndrome (TLS) is the most serious complication of oncology treatment. According to the literature, several cases reported TLS occurred with targeted therapies for hepatic cancer. METHODS: Reporting odds ratio and information component were used to measure the disproportionate signals for TLS associated with targeted therapies, using data from the FDA's Adverse Event Reporting System (FAERS). A stepwise sensitivity analysis was conducted to test the robustness of signals. Time-to-onset analysis was used to describe the latency of TLS events associated with targeted therapies. The Bradford Hill criteria were used to perform a global assessment of the evidence. RESULTS: Sorafenib, lenvatinib, cabozantinib, and bevacizumab showed higher disproportionate signals for TLS than chemotherapy. The median number of days to TLS occurrence after drug therapy was 5.5, 6.5, and 6.5 days for sorafenib, lenvatinib, and bevacizumab, respectively. CONCLUSIONS: There is a significant association between tumor lysis syndrome and targeted therapies for hepatic carcinoma, with particularly strong signals for sorafenib and lenvatinib. Clinicians should be aware of the potential for tumor lysis syndrome in targeted therapies for hepatic carcinoma.
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Pinus koraiensis polysaccharides (PKP) were extracted by hot water from P. koraiensis pine cones. Five polysaccharide fractions named PKP-A, PKP-B, PKP-C, PKP-D and PKP-E were successfully separated at final ethanol concentrations of 30%, 50%, 60%, 70% and 80%, respectively. HPLC, FT-IR, GC-MS and automatic amino-acid analysis were applied to investigate their chemical characteristics. Monosaccharide component analysis indicated that the five fractions were all composed of D-ribose, L-rhamnose, L-arabinose, D-xylose, D-mannose, D-glucose and D-galactose, but their molar ratios were quite different. HPLC results revealed that the polysaccharides precipitated by higher concentrations of ethanol solution had lower molecular masses. Moreover, the antioxidant activities of the five fractions were studied on the basis of hydroxyl radical and ABTS radical scavenging tests. The five graded polysaccharide fractions exhibited good inhibitory power, and MTT tests in vitro showed the IC50 of PKP-A and PKP-E were 1,072.5 and 2,070.0 µg · mL-1, respectively. These results demonstrated that the PKP could be a potential source of natural antioxidants or dietary supplements.
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Etanol/química , Pinus/química , Polissacarídeos/química , Arabinose/química , Cromatografia Líquida de Alta Pressão , Galactose/química , Cromatografia Gasosa-Espectrometria de Massas , Glucose/química , Manose/química , Ribose/química , Espectroscopia de Infravermelho com Transformada de Fourier , Xilose/químicaRESUMO
The traditional method of gas chromatography-mass spectrometry for monosaccharide component analysis with pretreatment of acetylation is described with slight modifications and verified in detail in this paper. It was then successfully applied to the quantitative analysis of component monosaccharides in polysaccharides extracted from the pine cones. The results demonstrated that the three pine cone polysaccharides all consisted of ribose, rhamnose, arabinose, xylose, mannose, glucose and galactose in different molar ratios. According to the recovery experiment, the described method was proved accurate and practical for the analysis of pine cone polysaccharides, meeting the need in the field of chemical analysis of Pinus plants. Furthermore; the chemical characteristics, such as neutral sugar, uronic acids, amino acids, molecular weights, and antioxidant activities of the polysaccharides were investigated by chemical and instrumental methods. The results showed that the chemical compositions of the polysaccharides differed from each other, especially in the content of neutral sugar and uronic acid. In the antioxidant assays, the polysaccharide fractions exhibited effective scavenging activities on ABTS radical and hydroxyl radical, with their antioxidant capabilities decreasing in the order of PKP > PAP > PSP. Therefore, although the polysaccharide fractions had little effect on superoxide radical scavenging, they still have potential to be developed as natural antioxidant agents in functional foods or medicine.
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Antioxidantes/química , Antioxidantes/farmacologia , Pinus/química , Polissacarídeos/química , Polissacarídeos/farmacologia , Antioxidantes/isolamento & purificação , Fracionamento Químico , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Radical Hidroxila/antagonistas & inibidores , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Polissacarídeos/isolamento & purificação , Reprodutibilidade dos Testes , Superóxidos/antagonistas & inibidoresRESUMO
Zinc is a necessary trace element and an important constituent of proteins and other biological molecules. It has many biological functions, including antioxidant, skin and mucous membrane integrity maintenance, and the promotion of various enzymatic and transcriptional responses. The skin contains the third most zinc in the organism. Zinc deficiency can lead to a range of skin diseases. Except for acrodermatitis enteropathic, a rare genetic zinc deficiency, it has also been reported in other diseases. In recent years, zinc supplementation has been widely used for various skin conditions, including infectious diseases (viral warts, genital herpes, cutaneous leishmaniasis, leprosy), inflammatory diseases (hidradenitis suppurativa, acne vulgaris, rosacea, eczematous dermatitis, seborrheic dermatitis, psoriasis, Behcet's disease, oral lichen planus), pigmentary diseases (vitiligo, melasma), tumor-associated diseases (basal cell carcinoma), endocrine and metabolic diseases (necrolytic migratory erythema, necrolytic acral erythema), hair diseases (alopecia), and so on. We reviewed the literature on zinc application in dermatology to provide references for better use.
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Despite being effective for many other solid tumors, traditional anti-angiogenic therapy has been shown to be insufficient for the treatment of malignant glioma. Here, we report the development of polyphenol nanoparticles (NPs), which not only inhibit the formation of new vessels but also enable targeted disruption of the existing tumor vasculature. The NPs are synthesized through a combinatory iron-coordination and polymer-stabilization approach, which allows for high drug loading and intrinsic tumor vessel targeting. We study a lead NP consisting of quercetin and find that the NP after intravenous administration preferentially binds to VEGFR2, which is overexpressed in tumor vasculature. We demonstrate that the binding is mediated by quercetin, and the interaction of NPs with VEGFR2 leads to disruption of the existing tumor vasculature and inhibition of new vessel development. As a result, systemic treatment with the NPs effectively inhibits tumor growth and increases drug delivery to tumors.
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Glioblastoma (GBM) is a deadly disease without effective treatment. Because glioblastoma stem cells (GSCs) contribute to tumor resistance and recurrence, improved treatment of GBM can be achieved by eliminating GSCs through inducing their differentiation. Prior efforts have been focused on studying GSC differentiation towards the astroglial lineage. However, regulation of GSC differentiation towards the neuronal and oligodendroglial lineages is largely unknown. To identify genes that control GSC differentiation to all three lineages, we performed an image-based genome-wide RNAi screen, in combination with single-cell RNA sequencing, and identified ZNF117 as a major regulator of GSC differentiation. Using patient-derived GSC cultures, we show that ZNF117 controls GSC differentiation towards the oligodendroglial lineage via the Notch pathway. We demonstrate that ZNF117 is a promising target for GSC differentiation therapy through targeted delivery of CRISPR/Cas9 gene-editing nanoparticles. Our study suggests a direction to improve GBM treatment through differentiation of GSCs towards various lineages.
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Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Glioblastoma/patologia , Humanos , Células-Tronco Neoplásicas/metabolismoRESUMO
An improved QuEChERS (quick, easy, cheap, effective, rugged, safe) method, combined with ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), was used to determine bongkrekic acid (BA) in tremella and auricularia auricular. BA is a fat-soluble, fatal bacterial toxin produced by the aerobic gram-negative bacteria Burkholderia gladioli pathovar cocovenenans. Tremella and auricularia auricular, which have rich nutritional values, are traditional edible fungi in China that are very popular among Chinese consumers. However, tremella and auricularia auricular are easily contaminated by BA during storage and foaming, and this poses a great threat to food safety and human health. Therefore, establishing a rapid and efficient analysis method for detecting BA in tremella and auricularia auricular is of considerable significance. However, the BA concentration in the actual sample is very low, and the matrices of tremella fuciformis and auricularia auricular are very complex. Thus, it is necessary to employ appropriate sample pretreatment technology to extract and purify BA from tremella and auricularia auricular samples prior to instrumental analysis. In this study, the QuEChERS method, combined with UHPLC-MS/MS, was used to detect BA in tremella and auricularia auricular. The key parameters, such as extraction solvent, extraction method, and adsorbent used for cleanup, were optimized to obtain high extraction efficiency. The content of acetic acid in the extraction solution strongly influenced the extraction efficiency of BA, and acetonitrile with 5%(v/v) acetic acid was determined to be the optimum extraction solvent. After salting out, the acetonitrile extract was purified by dispersive solid phase extraction using 200 mg C18 as a cleanup adsorbent. The sample was then separated on a Waters HSS T3 column (100 mm×2.1 mm, 1.8 µm), using a water solution containing 0.01% (v/v) formic acid and 0.05% (v/v) ammonia and methanol as mobile phases. MS analysis was performed using an electrospray ionization source in the negative and multiple reaction monitoring (MRM) modes. Under the optimized conditions, the matrix effects of UHPLC-MS/MS in tremella and auricularia auricular were -6.3% and -11.5%, respectively; this indicated that the method had a significant purification effect, and the sample matrix did not affect the MS detection of BA. Further study showed that in the concentration range of 1-200 µg/L, the square of the regression coefficient of the linear equation (R2) was greater than 0.999. The limit of detection (LOD) and limit of quantitation (LOQ) were 0.15 µg/kg and 0.5 µg/kg, respectively. The average recoveries in samples spiked with 0.5, 10, and 50 µg/kg BA in tremella ranged from 92.4% to 102.6%, and the intra-day and inter-day relative standard deviations (RSDs) were 4.3%-4.9% and 3.2%-3.5%, respectively. For auricularia auricular, the average recoveries ranged from 89.6% to 102.3%, and the intra-day and inter-day RSDs were 2.4%-9.5% and 3.6%-4.1%, respectively. These results indicate that the proposed method has satisfactory sensitivity, accuracy, and precision. Finally, the method showed good performance when applied to the analysis of real samples. Compared with other reported methods, the LOD and LOQ of our proposed method were lower, with satisfactory recovery and precision. Taken together, this study provides an effective detection technology for the monitoring and risk control of BA in tremella and auricularia auricular.
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Auricularia , Espectrometria de Massas em Tandem , Basidiomycota , Ácido Bongcréquico , Cromatografia Líquida de Alta Pressão , HumanosRESUMO
The polysaccharides (PKP-E) extracted from the pinecones of Pinus koraiensis were studied, which was fractionated using DEAE-52 cellulose and Sephadex G-100. Four novel polysaccharide fractions were obtained, which were PKP-E-1-1, -1-2, -2-1, and -2-2, respectively. The structural features were characterized using HPGPC, monosaccharide composition analysis, Congo red test, periodate oxidation, Smith degradation, FTIR and NMR spectroscopy. The results showed the 4 purified fractions were non-triple helical structured heteropolysaccharides and composed of l-rhamnose, l-arabinose, d-mannose, d-glucose, and d-galactose. The fractions were mainly linked by 1â6 or 1â glycosidic bonds and the backbone of 4 fractions was probably composed ofâ2, 6)-ß-d-Man-(1â and α-d-GalpA-(1â), which resembles pectin. Moreover, the antioxidant activities of the polysaccharides were measured by scavenging radical capacity tests. The PKP-E-2-1 was the most stable and active fraction, and the respective IC50 for the hydroxyl and ABTS·+ radicals were 3.0 and 23.6 mg/mL.
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Antioxidantes/farmacologia , Sequestradores de Radicais Livres/farmacologia , Radical Hidroxila/química , Monossacarídeos/química , Pinus/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Antioxidantes/química , Arabinose/química , Sequestradores de Radicais Livres/química , Alimento Funcional , Galactose/química , Glucose/química , Manose/química , Oxirredução , Polissacarídeos/química , Ramnose/químicaRESUMO
The blood-brain barrier (BBB) prevents antibodies from penetrating the CNS and limits conventional antibody-based approaches to brain tumors. We now show that ENT2, a transporter that regulates nucleoside flux at the BBB, may offer an unexpected path to circumventing this barrier to allow targeting of brain tumors with an anti-DNA autoantibody. Deoxymab-1 (DX1) is a DNA-damaging autoantibody that localizes to tumors and is synthetically lethal to cancer cells with defects in the DNA damage response. We found that DX1 penetrated brain endothelial cells and crossed the BBB, and mechanistic studies identify ENT2 as the key transporter. In efficacy studies, DX1 crosses the BBB to suppress orthotopic glioblastoma and breast cancer brain metastases. ENT2-linked transport of autoantibodies across the BBB has potential to be exploited in brain tumor immunotherapy, and its discovery raises hypotheses on actionable mechanisms of CNS penetration by neurotoxic autoantibodies in CNS lupus.
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Anticorpos Antinucleares/farmacologia , Autoanticorpos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Transportador Equilibrativo 2 de Nucleosídeo/metabolismo , Glioblastoma/tratamento farmacológico , Animais , Anticorpos Antinucleares/uso terapêutico , Autoanticorpos/uso terapêutico , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/patologia , Células CHO , Linhagem Celular , Cricetulus , Células Endoteliais , Transportador Equilibrativo 2 de Nucleosídeo/genética , Técnicas de Silenciamento de Genes , Glioblastoma/patologia , Humanos , Camundongos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Clustered regularly interspaced short palindromic repeats (CRISPR), a class of immune-associated sequences in bacteria, have been developed as a powerful tool for editing eukaryotic genomes in diverse cells and organisms in recent years. The CRISPR-Cas9 system can recognize upstream 20 nucleotides (guide sequence) adjacent to the protospacer-adjacent motif site and trigger double-stranded DNA cleavage as well as DNA repair mechanisms, which eventually result in knockout, knockin, or site-specific mutagenesis. However, off-target effect caused by guide sequence misrecognition is the major drawback and restricts its widespread application. In this study, global analysis of specificities of all guide sequences in Arabidopsis thaliana, Oryza sativa (rice), and Glycine max (soybean) were performed. As a result, a simple pipeline and three genome-wide databases were established and shared for the scientific society. For each target site of CRISPR-Cas9, specificity score and off-target number were calculated and evaluated. The mean values of off-target numbers for A. thaliana, rice, and soybean were determined as 27.5, 57.3, and 174.7, respectively. Comparative analysis among these plants suggested that the frequency of off-target effects was correlated to genome size, chromosomal locus, gene density, and guanine-cytosine (GC) content. Our results contributed to the better understanding of CRISPR-Cas9 system in plants and would help to minimize the off-target effect during its applications in the future.
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Arabidopsis/genética , Sistemas CRISPR-Cas , Glycine max/genética , Oryza/genética , Biologia Computacional , Edição de Genes/métodos , Marcação de Genes/efeitos adversos , Marcação de Genes/métodos , Genoma de Planta , Melhoramento Vegetal/métodos , Plantas Geneticamente Modificadas/genética , RNA Guia de Cinetoplastídeos/genéticaRESUMO
In recent years, various studies have confirmed the role of natural products as effective cancer prevention and treatment drugs. The present study demonstrated that chitosan oligosaccharide (COS) from shells of shrimp and crab caused an inhibitory effect on the proliferation of human renal carcinoma in vitro and in vivo. First, the in vivo biodistribution of COS was investigated by the synthesis of cyanine-7-labeled COS (COS-Cy7) following tail vein injection. The kidney was found to be a major target organ. Then, the impacts on renal carcinoma cell proliferation, apoptosis, and reactive oxygen species (ROS) production were observed in vitro, and an orthotopic xenograft tumor model was designed to evaluate the antitumor efficacy of COS in vivo. In renal carcinoma cells, COS induced G2/M phase arrest and apoptosis in a ROS-dependent fashion. COS significantly promoted mRNA expression of nuclear factor erythroid 2-related factor (Nrf2) and Nrf2 target genes, such as heme oxygenase 1, modifier subunit of glutamate cysteine ligase, and solute carrier family 7 member 11. Additionally, COS significantly upregulated the protein expression of glucose-regulated protein 78, protein RNA-like endoplasmic reticulum (ER) kinase, eukaryotic initiation factor 2α, activating transcription factor 4, C/EBP homologous protein, and cytochrome c, which justified the activation of the ER stress signaling pathway. In vivo, COS repressed tumor growth and induced apoptosis and ROS accumulation, consistent with the in vitro results. Taken together, COS repressed human renal carcinoma growth and induced apoptosis both in vitro and in vivo, mainly via ROS-dependent ER stress pathways.
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Carcinoma de Células Renais/tratamento farmacológico , Quitosana/administração & dosagem , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Neoplasias Renais/tratamento farmacológico , Oligossacarídeos/administração & dosagem , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/fisiopatologia , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Neoplasias Renais/fisiopatologia , Camundongos Nus , Fator 2 Relacionado a NF-E2 , Fator de Transcrição CHOPRESUMO
The perivascular niche (PVN) plays an essential role in brain tumor stem-like cell (BTSC) fate control, tumor invasion, and therapeutic resistance. Here, a microvasculature-on-a-chip system as a PVN model is used to evaluate the ex vivo dynamics of BTSCs from ten glioblastoma patients. BTSCs are found to preferentially localize in the perivascular zone, where they exhibit either the lowest motility, as in quiescent cells, or the highest motility, as in the invasive phenotype, with migration over long distance. These results indicate that PVN is a niche for BTSCs, while the microvascular tracks may serve as a path for tumor cell migration. The degree of colocalization between tumor cells and microvessels varies significantly across patients. To validate these results, single-cell transcriptome sequencing (10 patients and 21 750 single cells in total) is performed to identify tumor cell subtypes. The colocalization coefficient is found to positively correlate with proneural (stem-like) or mesenchymal (invasive) but not classical (proliferative) tumor cells. Furthermore, a gene signature profile including PDGFRA correlates strongly with the "homing" of tumor cells to the PVN. These findings demonstrate that the model can recapitulate in vivo tumor cell dynamics and heterogeneity, representing a new route to study patient-specific tumor cell functions.
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Stroke is a deadly disease without effective pharmacotherapies, which is due to two major reasons. First, most therapeutics cannot efficiently penetrate the brain. Second, single agent pharmacotherapy may be insufficient and effective treatment of stroke requires targeting multiple complementary targets. Here, we set to develop single component, multifunctional nanoparticles (NPs) for targeted delivery of glyburide to the brain for stroke treatment. Methods: To characterize the brain penetrability, we radiolabeled glyburide, intravenously administered it to stroke- bearing mice, and determined its accumulation in the brain using positron emission tomography-computed tomography (PET/CT). To identify functional nanomaterials to improve drug delivery to the brain, we developed a chemical extraction approach and tested it for isolation of nanomaterials from E. ulmoides, a medicinal herb. To assess the therapeutic benefits, we synthesized glyburide-loaded NPs and evaluated them in stroke- bearing mice. Results: We found that glyburide has a limited ability to penetrate the ischemic brain. We identified betulinic acid (BA) capable of forming NPs, which, after intravenous administration, efficiently penetrate the brain and significantly reduce ischemia-induced infarction as an antioxidant agent. We demonstrated that BA NPs enhance delivery of glyburide, leading to therapeutic benefits significantly greater than those achieved by either glyburide or BA NPs. Conclusion: This study suggests a new direction to identify functional nanomaterials and a simple approach to achieving anti-edema and antioxidant combination therapy. The resulting glyburide- loaded BA NPs may be translated into clinical applications to improve clinical management of stroke.
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Antioxidantes/administração & dosagem , Edema Encefálico/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Medicamentos de Ervas Chinesas/administração & dosagem , Glibureto/administração & dosagem , Acidente Vascular Cerebral/tratamento farmacológico , Triterpenos/administração & dosagem , Animais , Antioxidantes/química , Edema Encefálico/diagnóstico por imagem , Sistemas de Liberação de Medicamentos/instrumentação , Quimioterapia Combinada , Medicamentos de Ervas Chinesas/química , Eucommiaceae/química , Glibureto/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/química , Triterpenos Pentacíclicos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/diagnóstico por imagem , Triterpenos/química , Ácido BetulínicoRESUMO
Colon cancer is the third most common cancer, and yet there is a lack of effective therapeutic method with low side effects. Chitosan oligosaccharides (COS) is derived from chitosan after chitin deacetylation, and attracts more interests due to smaller molecular weight and soluble property. Previously, COS, mainly absorbed through intestinal epithelia, has been reported to exhibit many bioactivities, especially its anti-tumor effect. Recent references pay little attention to molecular weight distribution which is crucial for understanding its biological behavior. Here, we studied reducing sugar content and degree of polymerization (DP) of COS. 86.73% reducing sugar exists in COS sample and the content of chitosan fractions with 2-6 is 85.8%. COS suppressed the growth of HCT116 cells in vitro and in vivo, and the inhibition rate of tumor weight in vivo was high up to 58.6%. Moreover, the morphology observation, flow cytometry analysis and mRNA expression were applied to study the apoptosis related mechanism. COS treatment promoted mitosis, late stage apoptosis and S cell cycle arrest in HCT116 cells, and enhanced the mRNA expression of BAK and reduce BCL-2 and BCL-xL. These findings may provide an important clue for clinical applications of COS as anti-tumor drug or pharmaceutic adjuvant in the future.