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1.
JOR Spine ; 7(2): e1342, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38817341

RESUMO

Background: Normalized decision support system for lumbar disc herniation (LDH) will improve reproducibility compared with subjective clinical diagnosis and treatment. Magnetic resonance imaging (MRI) plays an essential role in the evaluation of LDH. This study aimed to develop an MRI-based decision support system for LDH, which evaluates lumbar discs in a reproducible, consistent, and reliable manner. Methods: The research team proposed a system based on machine learning that was trained and tested by a large, manually labeled data set comprising 217 patients' MRI scans (3255 lumbar discs). The system analyzes the radiological features of identified discs to diagnose herniation and classifies discs by Pfirrmann grade and MSU classification. Based on the assessment, the system provides clinical advice. Results: Eventually, the accuracy of the diagnosis process reached 95.83%. An 83.5% agreement was observed between the system's prediction and the ground-truth in the Pfirrmann grade. In the case of MSU classification, 95.0% precision was achieved. With the assistance of this system, the accuracy, interpretation efficiency and interrater agreement among surgeons were improved substantially. Conclusion: This system showed considerable accuracy and efficiency, and therefore could serve as an objective reference for the diagnosis and treatment procedure in clinical practice.

2.
Opt Express ; 31(17): 27462-27481, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710821

RESUMO

An embedded spherical dot taper structure (EDT) based on the MZI principle is proposed in this paper, which is mainly fabricated by using two special arc discharges in the preparation process. The proposed structure involves two specialized arc discharge techniques. First, an oversaturated discharge fusion process creates a micro-arc spherical area on the fiber end face to form the first link type. Second, an unsaturated discharge-pulling taper fusion joint creates a local micro-extrusion operation on this micro-arc fiber end face to form the second link. The thermal stress from instantaneous discharge causes a reverse spherical expansion zone to form in the end face structure, similar to the micromachining of long-period fiber gratings that use local CO2 laser etching to create modulated zones. The study involves a mathematical and theoretical analysis of how geometric parameters in the spherical modulation zone impact the structure's characteristic spectrum. The research demonstrates the potential for this structure to function as a light-intensity modulated strain sensor device through both theoretical and experimental means. As per the experimental findings, the optimized structure displays a high level of strain sensing sensitivity at 0.03 dB/µÎµ and temperature sensing sensitivity of 73 pm/°C (20°C-75°C) and 169 pm/°C (75°C-120°C). Additionally, it possesses excellent cross-sensitivity at only ∼0.0015 µÎµ/°C. Therefore, this sensor presents a favorable option for strain and temperature synchronization sensing and monitoring components, and exhibits notable application prospects in precision engineering, which encompasses mechanical manufacturing, the power and electrical industry, healthcare domain, and certain specialized areas of small-scale precision engineering.

3.
J Ginseng Res ; 47(5): 605-614, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37720567

RESUMO

Ginsenosides are bioactive components of Panax ginseng with many functions such as anti-aging, anti-oxidation, anti-inflammatory, anti-fatigue, and anti-tumor. Ginsenosides are categorized into dammarane, oleanene, and ocotillol type tricyclic triterpenoids based on the aglycon structure. Based on the sugar moiety linked to C-3, C-20, and C-6, C-20, dammarane type was divided into protopanaxadiol (PPD) and protopanaxatriol (PPT). The effects of ginsenosides on skin disorders are noteworthy. They play anti-aging roles by enhancing immune function, resisting melanin formation, inhibiting oxidation, and elevating the concentration of collagen and hyaluronic acid. Thus, ginsenosides have previously been widely used to resist skin diseases and aging. This review details the role of ginsenosides in the anti-skin aging process from mechanisms and experimental research.

4.
RSC Adv ; 13(4): 2248-2255, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36741156

RESUMO

The lymphatic system is a complex network of lymphatic vessels, lymph nodes, and lymphoid organs. The current understanding of the basic mechanism and framework of the lymphatic system is relatively limited and not ideal for exploring the function of the lymphatic system, diagnosing lymphatic system diseases, and controlling tumor metastasis. Imaging modalities for evaluating lymphatic system diseases mainly include lymphatic angiography, reactive dye lymphatic angiography, radionuclide lymphatic angiography, computed tomography, and ultrasonography. However, these are insufficient for clinical diagnosis. Some novel imaging methods, such as magnetic resonance imaging, positron emission computed tomography, single-photon emission computed tomography, contrast-enhanced ultrasonography, and near-infrared imaging with agents such as cyanine dyes, can reveal lymphatic system information more accurately and in detail. We fabricated an albumin-based fluorescent probe for dual-modality imaging of the lymphatic system. A near-infrared cyanine dye, IR-780, was absorbed into bovine serum albumin (BSA), which was covalently linked to a molecule of diethylenetriaminepentaacetic acid to chelate gadolinium Gd3+. The fabricated IR-780@BSA@Gd3+ nanocomposite demonstrates strong fluorescence and high near-infrared absorption and can be used as a T1 contrast agent for magnetic resonance imaging. In vivo dual-modality fluorescence and magnetic resonance imaging showed that IR-780@BSA@Gd3+ rapidly returned to the heart through the lymphatic circulation after it was injected into the toe webs of mice, facilitating good lymphatic imaging. The successful fabrication of the new IR-780@BSA@Gd3+ nanocomposite will facilitate the study of the mechanism and morphological structure of the lymphatic system.

5.
Eur J Immunol ; 52(12): 1980-1992, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36213961

RESUMO

Tolerogenic dendritic cells (tolDCs) have the potential to treat rheumatoid arthritis (RA) by inducing immune tolerance. However, the mechanism of intervention needs further study. Here, we investigated whether tolDCs formed microchimerism and their effect on the expression of immune checkpoint molecules after infusion of tolDCs into rats with collagen-induced arthritis (CIA). TolDCs derived from male SD rats were labeled with fluorescence and infused into female CIA rats. The fluorescence signals as well as the sex-determining region of Y-chromosome (SRY) gene revealed that tolDCs formed microchimerism in the mesenteric lymph nodes and ankle joints. We further explored the effect of tolDCs on the expression of immune checkpoint molecules in mesenteric lymph nodes and ankle joints. For stimulatory immune checkpoint molecules, the expressions of CD86 and CD40 decreased in mesenteric lymph nodes, and the expressions of CD40, CD40L, CD28, CD80, and CD86 also decreased in rat ankle joints. In contrast, the inhibitory immune checkpoint molecule PDL1 increased in mesenteric lymph nodes, and PD1, PDL1, and CTLA4 increased in ankle joints. In conclusion, our results suggested that intervention of tolDCs in CIA is associated with the formation of microchimerism and the effect on immune checkpoints.


Assuntos
Artrite Experimental , Proteínas de Checkpoint Imunológico , Feminino , Masculino , Ratos , Animais , Ratos Sprague-Dawley , Artrite Experimental/terapia , Células Dendríticas
6.
Mar Drugs ; 20(10)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36286417

RESUMO

Chemical investigation of the psychrophilic fungus Pseudogymnoascus sp. HDN17-933 derived from Antarctica led to the discovery of six new tetrapeptides psegymamides A-F (1-6), whose planar structures were elucidated by extensive NMR and MS spectrometric analyses. Structurally, psegymamides D-F (4-6) possess unique backbones bearing a tetrahydropyridoindoles unit, which make them the first examples discovered in naturally occurring peptides. The absolute configurations of structures were unambiguously determined using solid-phase total synthesis assisted by Marfey's method, and all compounds were evaluated for their inhibition of human (h) nicotinic acetylcholine receptor subtypes. Compound 2 showed significant inhibitory activity. A preliminary structure-activity relationship investigation revealed that the tryptophan residue and the C-terminal with methoxy group were important to the inhibitory activity. Further, the high binding affinity of compound 2 to hα4ß2 was explained by molecular docking studies.


Assuntos
Ascomicetos , Receptores Nicotínicos , Humanos , Receptores Nicotínicos/metabolismo , Simulação de Acoplamento Molecular , Triptofano , Regiões Antárticas , Ascomicetos/química
7.
Front Oncol ; 12: 926237, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35992843

RESUMO

Background: Globally, several generations of doctors in the field of lymphedema have created numerous publications. To date, no bibliometric analysis has been performed specifically on these publications. For the further promotion of research on lymphedema and to align with the international research frontiers, it is essential to understand the current state of Lymphedema research output. Objective: This study aims to statistically and visually analyze the characteristics of publications output, distribution of contributions and development process of lymphedema, enriching the knowledge base of Lymphedema, and then seek potential research topics and collaborators. Methods: Based on the Web of Science core collection database, we firstly analyzed the quantity and quality of publications in the field of lymphedema, secondly profiled the publishing groups in terms of country, institution, author's publication and cooperation network, and finally sorted out and summarized the hot topics of research. Results: A total of 8569 papers were retrieved from 1900-2021. The top4 journals with the most publications were LYMPHOLOGY, LYMPHATIC RESEARCH AND BIOLOGY, PLASTIC AND RECONSTRUCTIVE SURGERY and ANNALS OF SURGICAL ONCOLOGY. The top 4 countries with the most publications were USA, Japan, UK, and China. The United States dominates the total number of publications and the international cooperation network. The most productive research institution is Harvard University, and the research institution with the most collaborating institutions is Memorial Sloan Kettering Cancer Center. Mortimer, Peter S contributes the most research in this field. The research achievements of Japanese scholars in this field are of great significance. The top 5 ranked keywords are "Breast Cancer", "Health-Related Quality Of Life", "Lymphscintigraphy", "Lymphovenous Anastomosis", and "Lymphangiogenesis". Conclusion: More and more scholars are devoted to the research of cancer-related Lymphedema. It is foreseeable that breast cancer-related lymphedema and lymphangiogenesis will remain a focus of future research. Advances in Lymphatic vessel imaging and the development of lymphatic microsurgery will further play a role in the clinical workup of lymphedema. Meanwhile, This study can help researchers identify potential collaborators and partner institutions and contribute to further research.

8.
J Immunol Res ; 2022: 3815853, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35692503

RESUMO

Endometrial carcinoma (EC) is a commonly diagnosed gynecological malignancy. Interleukin-6 (IL6) plays a critical role in modulating the progression of several types of tumors, including EC. However, the specific mechanism of IL6 in regulating EC progression has not been clearly elucidated. In this study, we performed a series of functional experiments to explore the potential mechanisms involved in IL6 function in the progression of EC. Here, we found that IL6 increased reactive oxygen species (ROS) generation by enhancing the NADPH oxidase (NOX) level and induced mtDNA leakage in EC cells, which further caused the activation of the downstream cGAS-STING signaling and increased production of extracellular vesicle (EV) production from EC cells. Besides, the activation of cGAS-STING signaling enhanced the expression of type I IFN and its downstream molecule PD-L1 through the TBK1-IRF3 pathway. Importantly, a high level mtDNA and PD-L1 were present in EVs derived from IL6-induced EC cells; these vesicles were shown to be able to induce T cell apoptosis. Finally, anti-PD-L1 treatment in mice showed that blockade of PD-L1 significantly reversed tumor immune escape mediated by IL6-induced EVs. Together, we provide evidence that IL6 induced mtDNA leakage to regulate the immune escape of EC cells. Our findings may provide a novel clue for the development of therapeutic targets for EC.


Assuntos
Neoplasias do Endométrio , Interleucina-6 , Animais , Antígeno B7-H1 , DNA Mitocondrial/genética , Feminino , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo
9.
Mil Med Res ; 9(1): 25, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35624495

RESUMO

BACKGROUND: Cerebral ischemia-reperfusion injury (CIRI) refers to a secondary brain injury that can occur when the blood supply to the ischemic brain tissue is restored. However, the mechanism underlying such injury remains elusive. METHODS: The 150 male C57 mice underwent middle cerebral artery occlusion (MCAO) for 1 h and reperfusion for 24 h, Among them, 50 MCAO mice were further treated with Mitochondrial division inhibitor 1 (Mdivi-1) and 50 MCAO mice were further treated with N-acetylcysteine (NAC). SH-SY5Y cells were cultured in a low-glucose culture medium for 4 h under hypoxic conditions and then transferred to normal conditions for 12 h. Then, cerebral blood flow, mitochondrial structure, mitochondrial DNA (mtDNA) copy number, intracellular and mitochondrial reactive oxygen species (ROS), autophagic flux, aggresome and exosome expression profiles, cardiac tissue structure, mitochondrial length and cristae density, mtDNA and ROS content, as well as the expression of Drp1-Ser616/Drp1, RIP1/RIP3, LC3 II/LC3 I, TNF-α, IL-1ß, etc., were detected under normal or Drp1 interference conditions. RESULTS: The mtDNA content, ROS levels, and Drp1-Ser616/Drp1 were elevated by 2.2, 1.7 and 2.7 times after CIRI (P < 0.05). However, the high cytoplasmic LC3 II/I ratio and increased aggregation of p62 could be reversed by 44% and 88% by Drp1 short hairpin RNA (shRNA) (P < 0.05). The low fluorescence intensity of autophagic flux and the increased phosphorylation of RIP3 induced by CIRI could be attenuated by ROS scavenger, NAC (P < 0.05). RIP1/RIP3 inhibitor Necrostatin-1 (Nec-1) restored 75% to a low LC3 II/LC3 I ratio and enhanced 2 times to a high RFP-LC3 after Drp1 activation (P < 0.05). In addition, although CIRI-induced ROS production caused no considerable accumulation of autophagosomes (P > 0.05), it increased the packaging and extracellular secretion of exosomes containing p62 by 4 - 5 times, which could be decreased by Mdivi-1, Drp1 shRNA, and Nec-1 (P < 0.05). Furthermore, TNF-α and IL-1ß increased in CIRI-derived exosomes could increase RIP3 phosphorylation in normal or oxygen-glucose deprivation/reoxygenation (OGD/R) conditions (P < 0.05). CONCLUSIONS: CIRI activated Drp1 and accelerated the p62-mediated formation of autophagosomes while inhibiting the transition of autophagosomes to autolysosomes via the RIP1/RIP3 pathway activation. Undegraded autophagosomes were secreted extracellularly in the form of exosomes, leading to inflammatory cascades that further damaged mitochondria, resulting in excessive ROS generation and the blockage of autophagosome degradation, triggering a vicious cycle.


Assuntos
Isquemia Encefálica , Exossomos , Traumatismo por Reperfusão , Animais , Infarto Cerebral , DNA Mitocondrial , Exossomos/metabolismo , Glucose , Humanos , Inflamação , Masculino , Camundongos , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo , Reperfusão , Fator de Necrose Tumoral alfa
10.
Mar Drugs ; 20(5)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35621989

RESUMO

Five bergamotane sesquiterpenoid derivatives, brasilterpenes A-E (1-5), bearing an unreported spiral 6/4/5 tricyclic ring system, were isolated from the deep sea-derived ascomycete fungus Paraconiothyrium brasiliense HDN15-135. Their structures, including absolute configurations, were established by extensive spectroscopic methods complemented by single-crystal X-ray diffraction analyses, electronic circular dichroism (ECD), and density-functional theory (DFT) calculations of nuclear magnetic resonance (NMR) data including DP4+ analysis. The hypoglycemic activity of these compounds was assessed using a diabetic zebrafish model. Brasilterpenes A (1) and C (3) significantly reduced free blood glucose in hyperglycemic zebrafish in vivo by improving insulin sensitivity and suppressing gluconeogenesis. Moreover, the hypoglycemic activity of compound 3 was comparable to the positive control, anti-diabetes drug rosiglitazone. These results suggested brasilterpene C (3) had promising anti-diabetes potential.


Assuntos
Ascomicetos , Sesquiterpenos , Animais , Ascomicetos/química , Hipoglicemiantes/farmacologia , Sesquiterpenos/química , Peixe-Zebra
11.
Anal Cell Pathol (Amst) ; 2021: 8980711, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34926132

RESUMO

Glioma is the most common malignant tumor in adult brain characteristic with poor prognosis and low survival rate. Despite the application of advanced surgery, chemotherapy, and radiotherapy, the patients with glioma suffer poor treatment effects due to the complex molecular mechanisms of pathological process. In this paper, we conducted the experiments to prove the critical roles TET1 played in glioma and explored the downstream targets of TET1 in order to provide a novel theoretical basis for clinical glioma therapy. RT-qPCR was adopted to detect the RNA level of TET1 and ß-catenin; Western blot was taken to determine the expression of proteins. CCK8 assay was used to detect the proliferation of glioma cells. Flow cytometry was used to test cell apoptosis and distribution of cell cycle. To detect the migration and invasion of glioma cells, wound healing assay and Transwell were performed. It was found that downregulation of TET1 could promote the proliferation migration and invasion of glioma cells and the concomitant upregulation of ß-catenin, and its downstream targets like cyclinD1 and c-myc were observed. The further rescue experiments were performed, wherein downregulation of ß-catenin markedly decreases glioma cell proliferation in vitro and in vivo. This study confirmed the tumor suppressive function of TET1 and illustrated the underlying molecular mechanisms regulated by TET1 in glioma.


Assuntos
Neoplasias Encefálicas/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Oxigenases de Função Mista/genética , Proteínas Proto-Oncogênicas/genética , Via de Sinalização Wnt/genética , beta Catenina/genética , Animais , Apoptose/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação para Baixo , Glioma/metabolismo , Glioma/patologia , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Oxigenases de Função Mista/metabolismo , Invasividade Neoplásica , Proteínas Proto-Oncogênicas/metabolismo , Terapêutica com RNAi/métodos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , beta Catenina/metabolismo
12.
Cell Death Dis ; 12(11): 967, 2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34671019

RESUMO

RAN binding protein 10 (RANBP10), a ubiquitously expressed and evolutionarily conserved protein, as a RAN-GTP exchange factor (GEF) to regulate several factors involved in cellular progression. Previous studies showed that RANBP10 was overexpressed in prostate cancer cells and was responsible for androgen receptor (AR) activation. However, the biological function of RANBP10 in glioblastoma (GBM) has not been studied. Here, we found that RANBP10 was overexpressed in GBM, and high RANBP10 expression was closely linked to poor survival of patients with GBM. Downregulation of RANBP10 significantly inhibited cell proliferation, migration, invasion, and tumor growth of GBM cells. In addition, we revealed that RANBP10 could suppress the promoter activity of FBXW7, and thereby increase the protein stability of c-Myc in GBM cells. Silencing of FBXW7 in RANBP10-knockdown GBM cells could partly negate the effects induced by RANBP10 downregulation. Taken together, our findings established that RANBP10 significantly promoted GBM progression by control of the FBXW7-c-Myc axis, and suggest that RANBP10 may be a potential target in GBM.


Assuntos
Progressão da Doença , Proteína 7 com Repetições F-Box-WD/genética , Regulação Neoplásica da Expressão Gênica , Glioblastoma/patologia , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Transdução de Sinais , Adulto , Animais , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Proteína 7 com Repetições F-Box-WD/metabolismo , Feminino , Inativação Gênica , Humanos , Masculino , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Biológicos , Invasividade Neoplásica , Prognóstico , Estabilidade Proteica , Proteólise , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transcrição Gênica , Ensaio Tumoral de Célula-Tronco , Ubiquitinação
13.
Chin J Nat Med ; 19(7): 528-535, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34247776

RESUMO

In this study, three new germacranolide sesquiterpenes (1-3), together with six related known analogues (4-9) were isolated from the whole plant of Carpesium cernuum. Their structures were established by a combination of extensive NMR spectroscopic analysis, HR-ESIMS data, and ECD calculations. The anti-leukemia activities of all compounds towards three cell lines (HEL, KG-1a, and K562) were evaluated in vitro. Compounds 1-3 exhibited moderate cytotoxicity with IC50 values ranging from 1.59 to 5.47 µmol·L-1. Mechanistic studies indicated that 2 induced apoptosis by decreasing anti-apoptotic protein Bcl-2 and activating the caspase family in K562 cells. These results suggest that compound 2 is a potential anti-leukemia agent.


Assuntos
Antineoplásicos Fitogênicos , Asteraceae , Sesquiterpenos de Germacrano/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Asteraceae/química , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células K562 , Compostos Fitoquímicos/farmacologia
14.
Opt Express ; 29(4): 5141-5151, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33726055

RESUMO

We demonstrate theoretically and experimentally that the fast and slow light characteristics of the add-drop ring-resonator (ADRR) can be regulated by introducing an assisted ring. This novel geometry is named ring-assisted add-drop ring-resonator (RA-ADRR). When the assisted ring is under-coupled, the fast and slow light characteristics of through and drop ports of the RA-ADRR will be reversed, which is different from the coupled resonator induced transparency (CRIT) studied previously. With the decrease of loss, the dispersion peak (dip) of the two ports will grow up towards the opposite directions and finally the inversion occurs. Meanwhile, we find that by increasing the circumference of the assisted ring, the dispersion of the two ports could be improved proportionally. The experimental results show that the maximum group delays of the through and drop ports are 115 ns and -485 ns, respectively. This novel phenomenon could greatly enhance the sensitivity of slow light interferometers and also has potential applications in optical communication, network, filtering and switching.

15.
Int J Biol Macromol ; 180: 578-589, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33727188

RESUMO

G-quadruplex DNA (G4DNA) structure, which widely exists in the chromosomal telomeric regions and oncogenic promoter regions, plays a pivotal role in extending telomeric DNA with the help of telomerase in human cells. Bloom (BLM) helicase, a crucial member of the family of genome surveillance proteins, plays an essential role in DNA metabolic and repair pathways, including DNA replication, repair, transcription, recombination during chromosome segregation, and assuring telomere stability. The unwinding of G4DNA requires the participation of DNA helicase, which is crucial for maintaining chromosomal stability in cancer cells. Using fluorescence polarization and the electrophoretic mobility shift assay (EMSA), this study aimed to investigate the DNA-binding and unwinding properties of BLM helicase, cloned and purified from prostate cancer cells, toward G4DNA. The results revealed that BLM helicase derived from prostate cancer cells could bind and unwind G4DNA. The molecular affinity of bond between G4DNA and the helicase was dependent on the single-stranded DNA (ssDNA) terminals in G4DNA; the helicase was effectively bound to the G4DNA when the helicase monomer sufficiently covered approximately 10 nucleotides at the 3' or 5' ssDNA tail of G4DNA. For the unwinding of G4DNA, there was an apparent requirement of a 3' ssDNA tail and ATP; a G4DNA with only a 3' ssDNA tail was identified to be the most suitable substrate to be unwound by BLM helicase and required 3' ssDNA tails of at least 10 nt in length for efficient unwinding. Besides, BLM helicase was loosely bound and partly unwound the blunt-ended G4DNA. Although further mechanistic studies are warranted, the experimental results presented in this study are beneficial to further our understanding of the functional implication of BLM helicase in prostate cancer cells.


Assuntos
DNA/química , Quadruplex G , Neoplasias da Próstata/metabolismo , RecQ Helicases/metabolismo , Telômero/metabolismo , DNA/genética , DNA/metabolismo , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , DNA de Cadeia Simples/metabolismo , Humanos , Cinética , Masculino , Modelos Moleculares , Conformação de Ácido Nucleico , Células PC-3 , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Ligação Proteica , RecQ Helicases/genética , Especificidade por Substrato , Telômero/genética
16.
Cancer Manag Res ; 13: 379-392, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33469379

RESUMO

BACKGROUND: The dysregulation of long non-coding RNAs is a frequent finding in glioblastoma (GBM) and is considered as a crucial mechanism contributing to GBM oncogenesis and progression. The biological roles and underlying mechanisms of action of UBA6 antisense RNA 1 (UBA6-AS1) in GBM have been rarely investigated. Therefore, the aim of the present study was to investigate in detail the role of UBA6-AS1 in the modulation of the malignant properties of GBM and explore the possible underlying mechanism(s). METHODS: The expression of UBA6-AS1 in GBM was determined via reverse transcription-quantitative PCR. Cell Counting Kit-8 assay, flow cytometric analysis, Transwell migration and invasion assays, and in vivo tumorigenicity assay were applied to elucidate the biological effects of UBA6-AS1 on GBM cells. The possible biological events associated with UBA6-AS1 were investigated by luciferase reporter, RNA immunoprecipitation (RIP) and rescue assays. RESULTS: UBA6-AS1 was overexpressed in GBM, which was consistent with the data from The Cancer Genome Atlas database. In the case of UBA6-AS1 depletion, GBM cell proliferation, migration and invasion were notably decreased and cell apoptosis was enhanced in vitro. Additionally, knockdown of UBA6-AS1 suppressed the proliferation of GBM cells in vivo. Mechanistically, UBA6-AS1 functioned as a competing endogenous RNA by adsorbing miR-760 and, consequently, upregulating homeobox A2 (HOXA2) expression. Rescue experiments demonstrated that the UBA6-AS1 silencing-mediated regulatory effects on GBM cells were reversed by the decrease of miR-760 or restoration of HOXA2 expression. CONCLUSION: Therefore, the results of the present study revealed that UBA6-AS1 promoted the malignant progression of GBM via targeting the miR-760/HOXA2 axis, thereby representing a promising effective target for the treatment of GBM.

17.
RSC Adv ; 11(58): 36569-36576, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-35494388

RESUMO

In this study, silver (Ag) island modified up-conversion nano-particle (NaGdF4:Yb3+/Tm3+) thin films were prepared via electrostatic layer by layer (LBL) and spin coating techniques. The spectroscopic results indicated that adding Ag nanoparticles could significantly enhance the up-conversion emission of NaGdF4:Yb3+/Tm3+ thin films at 452 nm and 476 nm. The maximum enhancement factor of ∼15.6 was reached at 476 nm. Furthermore, we prepared microfibers from upconverting nanoparticles solution, the application of microfibers as active and passive waveguides was analyzed by observing the performance of microfibers with and without Ag under 980 nm excitation of the laser source. The fluorescence intensity ratio (FIR) method was adopted to evaluate microfiber sensitivity. The intensity-based temperature sensitivity of blue emission from a single microfiber containing up-conversion nanomaterials (NaGdF4:Yb3+/Tm3+) and Ag nanoparticles reached up to 0.018 K-1 at 310 K compared to 0.0029 K-1 in Ag-free microfiber. Our results suggest that the novel material can be used to construct new nano-thermometers, useful both in biological experiments as well as industrial research.

18.
Front Neurosci ; 14: 589050, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33328859

RESUMO

OBJECTIVE: To investigate the relationship between hematoma ventricle distance (HVD) and clinical outcome in patients with intracerebral hemorrhage (ICH). METHODS: We prospectively enrolled consecutive patients with ICH in a tertiary academic hospital between July 2011 and April 2018. We retrospectively reviewed images for all patients receiving a computed tomography (CT) within 6 h after onset of symptoms and at least one follow-up CT scan within 36 h. The minimum distance of hematoma border to nearest ventricle was measured as HVD. Youden index was used to evaluate the cutoff of HVD predicting functional outcome. Logistic regression model was used to assess the HVD data and clinical poor outcome (modified Rankin Scale 4-6) at 90 days. RESULTS: A total of 325 patients were included in our final analysis. The median HVD was 2.4 mm (interquartile range, 0-5.7 mm), and 119 (36.6%) patients had poor functional outcome at 3 months. After adjusting for age, admission Glasgow coma scale, intraventricular hemorrhage, baseline ICH volume, admission systolic blood pressure, blood glucose, hematoma expansion, withdrawal of care, and hypertension, HVD ≤ 2.5 mm was associated with increased odds of clinical poor outcome [odd ratio, 3.59, (95%CI = 1.72-7.50); p = 0.001] in multivariable logistic regression analysis. CONCLUSION: Hematoma ventricle distance allows physicians to quickly select and stratify patients in clinical trials and thereby serve as a novel and useful addition to predict ICH prognosis.

19.
Bioorg Chem ; 105: 104428, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33161249

RESUMO

AKR1B1 (Aldose reductase) has been used as therapeutic intervention target for treatment of diabetic complications over 50 years, and more recently for inflammation and cancer. However, most developed small molecule inhibitors have the defect of low bioactivity. To address this limitation, novel series of 3,4-dihydroquinolin-2(1H)-one derivatives as dual inhibitor targeting AKR1B1/ROS (Reactive Oxygen Species) were designed and synthesized. Most of these derivatives were found to be potent and selective against AKR1B1, and compound 8a was the most active with an IC50 value of 0.035 µM. Moreover, some prepared derivatives showed strong anti-ROS activity, and among them the phenolic 3,5-dihydroxyl compound 8b was proved to be the most potent, even comparable to that of the well-known antioxidant Trolox at a concentration of 100 µM. Thus the results suggested a success in the construction of potent dual inhibitor for the therapeutic intervention target of AKR1B1/ROS.


Assuntos
Aldeído Redutase/antagonistas & inibidores , Antioxidantes/farmacologia , Complicações do Diabetes/tratamento farmacológico , Inibidores Enzimáticos/farmacologia , Quinolonas/farmacologia , Espécies Reativas de Oxigênio/antagonistas & inibidores , Aldeído Redutase/metabolismo , Antioxidantes/síntese química , Antioxidantes/química , Compostos de Bifenilo/antagonistas & inibidores , Complicações do Diabetes/metabolismo , Relação Dose-Resposta a Droga , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Picratos/antagonistas & inibidores , Quinolonas/síntese química , Quinolonas/química , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
20.
Opt Lett ; 45(3): 754-757, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32004302

RESUMO

In this Letter, Autler-Townes splitting and induced transparency windows are observed in a multimode microfiber knot. The microfiber knot is fabricated using tapered single-mode fiber, with the knot position located at the transition area of the tapered fiber. The spectrum, in analogy to Autler-Townes splitting, derives from the mode splitting of two high-order excited modes, which is theoretically explained by the multimode transfer matrix method. Moreover, without adding resonators, two induced transparency windows are realized with the tunable coupling coefficients and phase difference of excited knot modes. The tunable, easily fabricated, compact, and robust microfiber knot has potential applications in optical sensing, filters, slow light, and optical switching.

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