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1.
Zhongguo Zhong Yao Za Zhi ; 49(10): 2619-2628, 2024 May.
Artigo em Zh | MEDLINE | ID: mdl-38812162

RESUMO

Nontraumatic avascular necrosis of the femoral head(NANFH) is a common and refractory femoral head disease that causes bone death due to interruption of blood supply. Early clinical symptoms are atypical, such as hip pain and limited joint function. In the late stage, severe pain, shortening of the affected limb, claudication, and other serious symptoms are common, which se-riously affects the quality of life of patients. Therefore, it is of great significance to actively improve the clinical symptoms of NANFH to enhance the quality of life of patients. The pathogenesis of NANFH is complex, such as traumatic vascular circulatory disorders, the use of hormones or other drugs, alcoholism, and diabetes mellitus. These factors directly or indirectly lead to femoral head vascular damage, thrombosis, and coagulation system disorders, which reduce the blood supply to the acetabulum and femoral head, thus causing ischaemic death of the femoral head or even femoral head collapse. NANFH is mainly categorized as "bone impotence" and "bone paralysis" in traditional Chinese medicine(TCM). The treatment of NANFH with TCM has the characteristics and advantages of a long history, stable and reliable therapeutic effect, fewer adverse reactions, good patient tolerance, and high acceptance. Previous studies have shown that the promotion of angiogenesis is a key initiative in the prevention and treatment of NANFH, and TCM can promote fe-moral head angiogenesis by interfering with the expression of angiogenesis-related factors, which in turn can help to restore the blood supply of the femoral head and thus improve clinical symptoms of NANFH and prevent and treat NANFH. This article described the roles of blood supply interruption and angiogenesis in NANFH and the accumulated knowledge and experience of TCM in NANFH and summarized the role of angiogenesis-related factors in NANFH and the research progress on TCM intervention, so as to provide an idea for the subsequent research and a new basis for the clinical application of TCM in the treatment of NANFH.


Assuntos
Medicamentos de Ervas Chinesas , Necrose da Cabeça do Fêmur , Humanos , Necrose da Cabeça do Fêmur/prevenção & controle , Necrose da Cabeça do Fêmur/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/administração & dosagem , Medicina Tradicional Chinesa , Animais , Cabeça do Fêmur/irrigação sanguínea , Neovascularização Patológica/tratamento farmacológico , Neovascularização Fisiológica/efeitos dos fármacos , Angiogênese
2.
Inorg Chem ; 61(18): 6819-6828, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35475364

RESUMO

Four new isostructural lanthanide metal-organic frameworks (MOFs), namely {[Ln(DMTP-DC)1.5(H2O)3]·DMF}n [H2DMTP-DC = 2',5'-dimethoxytriphenyl-4,4″-dicarboxylic acid; LnIII = EuIII (1), GdIII (2), TbIII (3), and DyIII (4)], have been synthesized and characterized. Single-crystal structure analysis reveals that 1-4 are three-dimensional Ln-MOFs with rich H-bonding of coordinated H2O molecules in the network channels. The X-ray diffraction patterns indicate that Ln-MOF 1 displays good stabilities in organic solvents and aqueous solutions with distinct pH values. Both 1 and 3 show characteristic emission of LnIII ions. Ln-MOF 1 can be used as a ratiometric fluorescence sensor for arginine and lysine in aqueous solution, and the detection limits are 24.38 µM for arginine and 9.31 µM for lysine. All 1-4 show proton conductivity related to relative humidity (RH) and temperature, and the maximum conductivity values of 1-4 at 55 °C and 100% RH are 9.94 × 10-5, 1.62 × 10-4, 1.71 × 10-4, and 2.67 × 10-4 S·cm-1, respectively. The value of σ increases with the decrease in ionic radius, indicating that the radius of the LnIII ions can regulate the proton conductivity of these MOFs. Additionally, 2 exhibits a significant magnetocaloric effect (MCE) with a magnetic entropy change (-ΔSm) of 18.86 J kg-1 K-1 for ΔH = 7 T at 2 K, and 4 shows weak field-induced slow relaxation of magnetization. The coexistence of good fluorescence sensing capability, attractive proton conductivity, and relatively large MCE in Ln-MOFs is rare, and thus, 1-4 are potentially multifunctional MOF materials.


Assuntos
Elementos da Série dos Lantanídeos , Estruturas Metalorgânicas , Aminoácidos , Arginina , Fluorescência , Elementos da Série dos Lantanídeos/química , Lisina , Estruturas Metalorgânicas/química , Prótons , Água
3.
J Cell Biochem ; 119(11): 9168-9177, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30136305

RESUMO

Recent evidence has demonstrated that circular RNAs (circRNAs) played crucial roles in fine-tuning the levels of gene expression by sequestering the corresponding microRNA (miRNAs). Their interaction with disease-associated miRNAs indicates that circRNAs are important for the development of disease, and miR-145 has been previously shown to have antitumor effect in prostate cancer. In the current study, we successfully established the miR-145-overexpressed prostate cancer LNCaP cells (LNCaP-miR-145) using lentiviral vectors. LNCaP cells expressing the empty vector (LNCaP-NC) were used as the negative control. The circRNA expression in LNCaP-miR-145 cells was detected by microarray analysis, and the miRNA targets of circRNAs were predicted using the bioinformatics software TargetScan and miRanda. Quantitative reverse transcription polymerase chain reaction was used to detect the expression levels of circRNAs in the prostate cancer tissue, nonmalignant tissue, LNCaP-miR-145 cells, and LNCaP-NC cells. The interaction of miRNA and circRNA was further confirmed by the dual-luciferase reporter assay. A total of 267 and 149 circRNAs were significantly up- and downregulated in LNCaP-miR-145 cells, respectively. hsa_circRNA_101981, hsa_circRNA_101996 and hsa_circRNA_09142 were the 3 circRNAs that interacted with hsa-miR-145-5p; hsa_circRNA_008068 and hsa_circRNA_406557 were the 2 circRNAs that interacted with hsa-miR-145-3p. Most of the circRNAs corresponded to the protein-coding exons. The expression levels of hsa_circRNA_101981, hsa_circRNA_00806, and hsa_circRNA_406557 were upregulated in the LNCaP-miR-145 cells, but downregulated in the prostate cancer tissue. In contrast, the expression levels of hsa_circRNA_101996 and hsa_circRNA_091420 were downregulated in the LNCaP-miR-145 cells, but upregulated in the prostate cancer tissue. Moreover, miR-145-5P might regulate the expression of hsa_circRNA_101981, hsa_circRNA_101996, and hsa_circRNA_09142, while miR-145-3P might regulate the expression of hsa_circRNA_008068 and hsa_circRNA_406557. Overexpression of miR-145 promoted the expression of hsa_circRNA_101981, hsa_circRNA_008068, and hsa_circRNA_406557 but suppressed the expressions of hsa_circRNA_101996 and hsa_circRNA_091420 in LNCaP cells. The results from the current study should give us a clue to clarify the tumor suppressive effect of miR-145.


Assuntos
MicroRNAs/genética , Neoplasias da Próstata/genética , RNA/genética , Linhagem Celular , Linhagem Celular Tumoral , Humanos , Masculino , Análise em Microsséries , RNA Circular , Reação em Cadeia da Polimerase em Tempo Real
4.
Cell Physiol Biochem ; 49(4): 1539-1550, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30212824

RESUMO

BACKGROUND/AIMS: Circular RNAs (circRNAs), a type of RNA that is widely expressed in human cells, have essential roles in the development and progression of cancer. CircRNAs contain microRNA (miRNA) binding sites and can function as miRNA sponges to regulate gene expression by removing the inhibitory effect of an miRNA on its target gene. METHODS: We used the bioinformatics software TargetScan and miRanda to predict circRNA-miRNA and miRNAi-Mrna interactions. Rate of inhibiting of proliferation was measured using a WST-8 cell proliferation assay. Clone formation ability was assessed with a clone formation inhibition test. Cell invasion and migration capacity was evaluated by performing a Transwell assay. Relative gene expression was assessed using quantitative real-time polymerase chain reaction and relative protein expression levels were determined with western blotting. circRNA and miRNA interaction was confirmed by dual-luciferase reporter and RNA-pull down assays. RESULTS: In the present study, the miRNA hsa-miR-21-5p was a target of circRNA-ACAP2, and T lymphoma invasion and metastasis protein 1 (Tiam1) was identified as a target gene of hsa-miR-21-5p. CircRNA-ACAP2 and Tiam1 were shown to be highly expressed in colon cancer tissue and colon cancer SW480 cells, but miR-21-5p was expressed at a low level. SW480 cell proliferation was suppressed when the expression of circRNA-ACAP2 and Tiam1 was decreased and the expression of miR-21-5p was increased in vivo and in vitro. SW480 cell migration and invasion were also inhibited under the same circumstance. The circRNA-ACAP2 interaction regulated the expression of miR-21-5p, and miR-21-5p regulated the expression of Tiam1. Down-regulation of circRNA-ACAP2 promoted miR-21-5p expression, which further suppressed the transcription and translation of Tiam1. CONCLUSION: The present study shows that the circRNA-ACAP2/hsa-miR-21-5p/Tiam1 regulatory feedback circuit could affect the proliferation, migration, and invasion of colon cancer SW480 cells. This was probably due to the fact that circRNA-ACAP2 could act as a miRNA sponge to regulate Tiam1 expression by removing the inhibitory effect of miR-21-5p on Tiam1 expression. The results from this study have revealed new insights into the pathogenicity of colon cancer and may provide novel therapeutic targets for the treatment of colon cancer.


Assuntos
Neoplasias do Colo/patologia , Proteínas de Membrana/genética , MicroRNAs/metabolismo , RNA/metabolismo , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/metabolismo , Regiões 3' não Traduzidas , Animais , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Retroalimentação Fisiológica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , RNA/antagonistas & inibidores , RNA/genética , Interferência de RNA , RNA Circular , RNA Interferente Pequeno/metabolismo , RNA Interferente Pequeno/uso terapêutico , Alinhamento de Sequência , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/antagonistas & inibidores , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/genética
5.
Molecules ; 23(6)2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29799496

RESUMO

A novel 36-metallacrown-6 complex [CuL(N(CN)2)(PF6)]6∙0.5H2O 1 was achieved using a tridendate ligand, 1,4,7-triisopropyl-1,4,7-triazacyclononane (L), and a flexible ligand, dicyanamide in MeOH. The µ1,5 bridging models of the dicyanamide ligand linked the macrocycle to form in a specific size with the chair conformation. The anion was important to form this 36-metallacrown-6 complex, as change was obtained with the larger anion BPh4-, binuclear copper compound 2. The magnetic property indicates that slightly ferromagnetic interactions resulted from a superexchange mechanism. DNA binding properties were also studied. UV and fluorescence spectra showed that complex 1 could bind with DNA.


Assuntos
Cobre/química , Cianetos/química , DNA/química , Compostos Heterocíclicos/química , Compostos Organometálicos/química , Sítios de Ligação , Cristalografia por Raios X , Cianetos/síntese química , Compostos Heterocíclicos/síntese química , Campos Magnéticos , Conformação Molecular , Compostos Organometálicos/síntese química
6.
J Cell Biochem ; 118(11): 3713-3721, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28374914

RESUMO

Evidence is accumulating that long non-coding RNAs (lncRNAs) are involved in human tumorigenesis and dysregulated in many cancers, including hepatocellular carcinoma (HCC). Because lncRNAs can regulate essential pathways that contribute to tumor initiation and progression with their tissue specificity, lncRNAs are valuable biomarkers and therapeutic targets. Maternally expressed gene 3 (MEG3) is a lncRNA overexpressed in HCC cells that inhibits HCC progression, however, the mechanism remains largely unknown. Recently, a novel regulatory mechanism has been proposed in which RNAs can cross-talk with each other via competing for shared microRNAs (miRNAs). The proposed competitive endogenous RNAs could mediate the bioavailability of miRNAs on their targets, thus imposing another level of post-transcriptional regulation. In the current study, we demonstrated that MEG3 is down-regulated in HCC tissues. MEG3 over-expression imposes another level of post-transcriptional regulation, whereas MEG3 overexpression increase the expression of the miR-664 target gene, ADH4, through competitive "sponging" miR-664. In addition, NF-κB may affect transcription of MEG3 by directly binding to the promoter region. Our data revealed that NF-κB may affect the transcript of MEG3. MEG3 overexpression inhibited the proliferation of HCC cells, at least in part by affecting miR-664mediated regulation of ADH4. Together, these results suggest that MEG3 is a suppressor of tumor which acts in part through "sponging" miR-664. J. Cell. Biochem. 118: 3713-3721, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/metabolismo , MicroRNAs/biossíntese , RNA Longo não Codificante/biossíntese , RNA Neoplásico/biossíntese , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , RNA Longo não Codificante/genética , RNA Neoplásico/genética
7.
Tumour Biol ; 2016 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-27743381

RESUMO

Rapidly accumulated evidence has shown that long non-coding RNA (lncRNAs) disregulation is involved in human tumorigenesis in many cancers, including prostate cancer (PCa). LncRNAs can regulate essential pathways that contribute to tumor initiation and progression with tissue specificity, which suggests that lncRNAs could be valuable biomarkers and therapeutic targets. Prostate cancer antigen 3 (PCA3), also known as differential display code 3 (DD3), is one such lncRNA that maps to chromosome 9q21-22. PCA3 expression is highly specific to PCa. In the present study, the level of PCA3 expression in prostate cancer cells was reduced by small interfering RNA (siRNA). Subsequently, the ability of LNCaP cell proliferation, invasion, and migration of PCa was compromised both in vivo and in vitro with the occurrence of cell autophagy. Recently, a novel regulatory mechanism has been proposed in which RNAs cross talk via competing with the shared microRNAs (miRNAs). In addition, lncRNAs can directly interact with RNA-binding proteins and then bind to the gene promoter region to further regulate gene expression. The proposed competitive endogenous RNAs mediate the bioavailability of miRNAs on their targets, thus imposing another level of post-transcriptional regulation. Here, we demonstrated that binding of Snail to the promoter region of PCA3 could activate the expression of PCA3. Down-regulation of PCA3 by silencing could increase the expression of the miRNA-1261, which then targeted at the PRKD3 gene (protein kinase D3) through competitive sponging. In summary, these results suggest that the transcription factor, Snail, activated the expression of lncRNA PCA3, which could inhibit the translation of PRKD3 protein via competitive miR-1261 sponging, and thus high expression of PRKD3 further promoted invasion and migration of prostate cancer.

8.
Chin Med Sci J ; 28(2): 122-3, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23806377

RESUMO

With the development of genome-wide sequencing technology, 195 types of functional long non-coding RNAs (lncRNAs) have so far been found, and their cellular roles are gradually being revealed. Now lncRNAs have become a hotspot in the life science. These small molecules exist in almost all higher eukaryotes, and have very important regulatory roles in these organisms. This review briefly summarizes recent progress in researches on antisense non-coding RNA in the INK4 locus.


Assuntos
Proteínas Inibidoras de Quinase Dependente de Ciclina/genética , Loci Gênicos , RNA Antissenso/fisiologia , RNA Longo não Codificante/fisiologia , Animais , Humanos
9.
J Enzyme Inhib Med Chem ; 27(4): 528-32, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22809106

RESUMO

Two mononuclear copper(II) complexes, [Cu(C(15)H(16)NO(2))(2)] (1) and [Cu(C(6)H(9)N(2)O(4))(2)·3H(2)O] (2·3H(2)O), were synthesised and structurally characterised by single-crystal X-ray analysis. The copper(II) atom adopts a square-planar environment in complex 1, while the geometry in 2·3H(2)O could be described as the distorted square pyramidal. Complexes 1 and 2·3H(2)O were evaluated for their inhibitory activities against Helicobacter pylori (H. pylori) urease in vitro. They both were found to have strong inhibitory activities against H. pylori urease comparable to that of acetohydroxamic acid (AHA). A docking simulation was performed to position 2 into the H. pylori urease active site to determine the probable binding conformation.


Assuntos
Cobre/química , Helicobacter pylori/enzimologia , Compostos Organometálicos/farmacologia , Urease/antagonistas & inibidores , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Modelos Moleculares , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Relação Estrutura-Atividade , Urease/metabolismo
10.
Cancer Invest ; 29(4): 286-92, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21469977

RESUMO

A higher expression of S-100 in tissue of thyroid papillary carcinoma (TPC) vs. thyroid follicular adenoma (TFA) (p < .001) was observed as well as a higher expression of CD83 in the peri-cancerous tissues vs. TFA (p < .001), oppositely, CD83 was negative in the cancerous net. TPC showed greater decreases in levels of CD80 and CD86 than did the TFA. These findings suggest that impaired immune function, absence of CD83-positive mature and activated dendritic cells in cancer nodules may have a role in the pathogenesis of TPC. The low expression of CD80 and CD86 in TPC may help them evade the immune system.


Assuntos
Adenoma/imunologia , Antígenos CD/metabolismo , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Células Dendríticas/imunologia , Imunoglobulinas/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas S100/metabolismo , Adulto , Idoso , Carcinoma , Carcinoma Papilar , Estudos de Casos e Controles , Células Cultivadas , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/imunologia , Fatores de Tempo , Evasão Tumoral , Antígeno CD83
11.
Psychiatry Res ; 194(3): 385-392, 2011 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-22047727

RESUMO

Stress-induced hippocampal volume loss and decrease in N-acetylaspartate (NAA) level have been reported to be associated with impaired neural plasticity and neuronal damage in adults. Accordingly, reversing structural and metabolite damage in the hippocampus may be a desirable goal for antidepressant therapy. The present study investigated the effects of tianeptine on chronic stress-induced hippocampal volume loss and metabolite alterations in vivo in 24 Sprague-Dawley rats. Rats were subjected to a consecutive 28-day forced swimming test stress. Tianeptine (50mg/kg) or saline was administered intragastrically 4h after swimming each day. Spontaneous behaviors, serum corticosterone concentration, hippocampal volume and NAA level were evaluated after stress. Chronic tianeptine treatment counteracted the chronic stress-induced suppression of spontaneous behaviors, elevated serum corticosterone concentration, reduced hippocampal volume and decreased NAA level. Moreover, we found asymmetrical right-left hippocampal volume loss in stressed rats, with the left hippocampus more sensitive to chronic stress than the right hippocampus. In addition, stressed rats showed a decreased level of hippocampal metabolites, without significant loss of hippocampal volume. These findings provide experimental evidence for impaired structural plasticity of the brain being an important feature of depressive illness and suggest that prophylactic tianeptine treatments could reverse structural changes in brain. The structural and neurochemical alterations in the hippocampus may be valuable indexes for evaluating the prophylactic and curative effect of antidepressant treatments in depressive and stress-related disorders.


Assuntos
Antidepressivos Tricíclicos/farmacologia , Ácido Aspártico/análogos & derivados , Hipocampo , Estresse Psicológico/patologia , Tiazepinas/farmacologia , Análise de Variância , Animais , Antidepressivos Tricíclicos/uso terapêutico , Ácido Aspártico/metabolismo , Colina/metabolismo , Cromatografia Líquida de Alta Pressão , Corticosterona/sangue , Creatina/metabolismo , Modelos Animais de Doenças , Comportamento Exploratório/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Prótons , Ratos , Ratos Sprague-Dawley , Estatística como Assunto , Estresse Psicológico/tratamento farmacológico , Tiazepinas/uso terapêutico
12.
Zhonghua Yu Fang Yi Xue Za Zhi ; 45(8): 742-4, 2011 Aug.
Artigo em Zh | MEDLINE | ID: mdl-22169698

RESUMO

OBJECTIVE: This study aims to investigate the bacteria contamination on hands of funeral staffs in different positions. METHODS: Bacterial samples were collected from the hands of 105 funeral staffs in different positions (including 90 frontline staffs and 15 administrative workers) from 13 funeral parlors nationwide, and were subsequently tested by bacterium inspection. RESULTS: In total, 1783 strains of bacteria were isolated, including 1027 Gram-positive bacteria, most of which were Staphylococcus; and 756 Gram-negative bacteria, most of which were Pseudomonas. Out of the 1783 strains of bacteria, 570 pathogens and opportunistic pathogens were isolated, accounted to 31.96%. The isolated ratio of pathogens and conditional pathogens in embalmed/cosmetologist of cadavers was 35.67% (370/1037), which was higher than those in the funeral workers in other positions, such as cremators, pick-up and administrative workers, whose ratios were 24.42% (95/389), 22.41% (52/232) and 10.40% (12/125), respectively (χ(2) were 13.682, 10.967 and 32.263, respectively; P values were all < 0.05). And the isolated ratios of pathogens and conditional pathogens in cremators and pick-up workers were significantly higher than that in administrative workers (χ(2) were 11.206 and 7.873, respectively; P values were all < 0.05). CONCLUSION: Lots of bacteria were found in the samples from hands of funeral staffs. The isolated ratio of pathogens and conditional pathogens was different between the funeral staffs in different positions; while the highest was from embalmed/cosmetologist of cadavers and the lowest was from administrators.


Assuntos
Mãos/microbiologia , Práticas Mortuárias , Exposição Ocupacional , Bactérias/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana
13.
Front Oncol ; 11: 685219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34084751

RESUMO

[This corrects the article DOI: 10.3389/fonc.2019.00477.].

14.
Dalton Trans ; 50(41): 14714-14723, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34586106

RESUMO

The reaction of the redox-active tetrathiafulvalene ligand and lanthanide ions is an important approach to prepare photo-electro-magnetic multifunctional metal-organic framework materials. A series of isostructural lanthanide metal-organic frameworks (Ln-MOFs) based on the in situ generated tetrathiafulvalene dicarboxylate (TTF-DC) ligand, {[Ln4(TTF-DC)6(DMF)4(H2O)2]·4DMF}n (Ln = Gd (1-Gd), Tb (1-Tb), Dy (1-Dy) and Er (1-Er)), was synthesized and characterized. These Ln-MOFs display tunable redox-active properties and semiconductor performance, and their electronic conductivities have been significantly improved after oxidation. All MOFs except 2-Tb exhibit slow magnetic relaxation under an applied dc field. 1-Dy and 2-Dy show field-induced single-molecule magnet (SMM) behaviour with energy barriers (Ueff) of 30.77 K (τ0 = 5.23 × 10-8) and 26.41 K (1.04 × 10-8 s), respectively.

15.
Micromachines (Basel) ; 12(3)2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33670962

RESUMO

With the development of micromachining technologies, a wider use of microchannel heat sink (MCHS) is achieved in many fields, especially for cooling electronic chips. A microchannel with a width of 500 µm and a height of 500 µm is investigated through the numerical simulation method. Pin fins are arranged at an inclined angle of 0°, 30°, 45°, and 60°, when arrangement method includes in-lined pattern and staggered pattern. The effects of inclined angle and arrangement method on flow field and temperature field of MCHSs are studied when Reynolds number ranges from 10 to 300. In addition to this, quantitative analyses of hydraulic and thermal performance are also discussed in this work. With the increase of inclined angle, the variation of friction factor and Nusselt number do not follow certain rules. The best thermal performance is achieved in MCHS with in-lined fines at an inclined angle of 30° accompanied with the largest friction factor. Arrangement method of pin fins plays a less significant role compared with inclined angle from a general view, particularly in the Reynolds number range of 100~300.

16.
Biochem Cell Biol ; 88(4): 665-70, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20651838

RESUMO

This study was designed to explore the effects of amiloride, a Na+-H+ exchange (NHE) inhibitor, on vessel stenosis by observing the expression of NHE-1 protein in vascular smooth muscle (VSM) after balloon injury and the effects of amiloride on VSM cell proliferation, migration, and excretion of extracellular matrices (ECMs). A total of 32 adult male New Zealand white rabbits were randomly divided into a balloon injury group (BG), an amiloride-treated group (AG), and a sham-operated group (SG). The left iliac artery was injured by inflating a 2.5 mm x 20 mm Foley catheter in BG and AG rabbits; in SG rabbits, the Foley catheter was inserted but not inflated. Amiloride (5 mg x kg(-1) x d(-1)) was injected intraperitoneally in AG and the same volume of distilled water was used in BG 3 days before balloon injury and for 28 days after the injury. The left iliac artery was stained by hematoxylin-eosin, alpha-actin, and Masson's trichrome to observe the vessel cava, neointima, media layer, and ECMs. NHE-1 proteins of the VSM were detected by Western blotting. A narrowing of the arterial cava, neointima formation, and thickened VSM layer were observed 28 days after balloon injury in BG and AG. However, in AG, the vessel cava was not as narrowed as that of BG and the intimal areas were to a lesser extent than in BG. In AG, the alpha-actin-positive areas and the ECM areas in the neointima were increased compared with SG, but to a lesser extent than in BG. The expression of NHE-1 protein in VSM was increased in BG and AG after balloon injury; however, the levels in AG were significantly less than in BG. In conclusion, VSM cell proliferation, migration, and excretion of ECMs contributed to vessel stenosis in the BG and AG rabbits. The expression of NHE-1 protein in VSM increased after balloon injury. Amiloride, an inhibitor of NHE-1, can limit the development of vessel stenosis through inhibition of VSM cell proliferation, migration, and excretion of ECMs.


Assuntos
Amilorida/farmacologia , Oclusão com Balão/efeitos adversos , Artéria Ilíaca/efeitos dos fármacos , Artéria Ilíaca/lesões , Artéria Ilíaca/patologia , Animais , Movimento Celular/efeitos dos fármacos , Constrição Patológica , Diuréticos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Células Endoteliais/fisiologia , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Doenças Vasculares Periféricas/etiologia , Doenças Vasculares Periféricas/metabolismo , Doenças Vasculares Periféricas/patologia , Coelhos , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores , Trocadores de Sódio-Hidrogênio/metabolismo , Túnica Íntima/efeitos dos fármacos
17.
Front Genet ; 11: 9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32158464

RESUMO

Circular RNA (circRNA), a type of RNA that is widely expressed in mammalian cells, is considered to be essential in tumorigenesis. CircRNA can regulate target gene expression by interacting with the corresponding microRNA (miRNA). Our preliminary results showed that the expression levels of 1,817 circRNAs were significantly different in colon cancer tissue compared with paracancerous tissue, of which 1,236 were upregulated and 581 were downregulated. By using RT-PCR, we confirmed that the expression of hsa_circ_0007843, hsa_circ_0010575, hsa_circ_0007331, and hsa_circ_0001615 was significantly higher in colon cancer tissue than in normal colonic tissue; however, the expression levels of hsa_circ_0014879 and hsa_circRNA_401801 were not significantly different between normal and neoplastic colonic tissue. Among the circRNAs that were confirmed to be upregulated in colon cancer tissue, hsa_circ_0007843 was also found to be highly expressed in colon cancer SW480 cells. Overexpression of hsa_circ_0007843 promoted the invasion and migration of SW480 cells, whereas its downregulation suppressed their invasion and migration. Overexpression of hsa_circ_0007843 promoted tumor growth, whereas its downregulation inhibited tumor growth. We found that hsa_circ_0007843 interacted with miR-518c-5p and suppressed its expression, and miR-518c-5p interacted with matrix metallopeptidase 2 (MMP2) and promoted its expression and translation. Taken together, this study demonstrated that hsa_circ_0007843 acted as an miRNA sponge to regulate MMP2 expression by removing the inhibitory effect of miR-518c-5p on MMP2 gene translation, which further affected the invasive capability of SW480 cells.

18.
Asian J Androl ; 11(2): 266-71, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19169266

RESUMO

We have observed earlier that testosterone at physiological concentrations can stimulate tissue factor pathway inhibitor (TFPI) gene expression through the androgen receptor in endothelial cells. This study further investigated the impact of testosterone on TFPI levels in response to inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha). Cultured human umbilical vein endothelial cells were incubated in the presence or absence of testosterone or TNF-alpha. TFPI protein and mRNA levels were assessed by enzyme-linked immunosorbent assay and quantitative real-time reverse transcription polymerase chain reaction. To study the cellular mechanism of testosterone's action, nuclear factor-kappa B (NF-kappaB) translocation was confirmed by electrophoretic mobility shift assays. We found that after NF-kappaB was activated by TNF-alpha, TFPI protein levels declined significantly by 37.3% compared with controls (P < 0.001), and the mRNA levels of TFPI also decreased greatly (P < 0.001). A concentration of 30 nmol L(-1) testosterone increased the secretion of TFPI compared with the TNF-alpha-treated group. NF-kappaB DNA-binding activity was significantly suppressed by testosterone (P < 0.05). This suggests that physiological testosterone concentrations may exert their antithrombotic effects on TFPI expression during inflammation by downregulating NF-kappaB activity.


Assuntos
Androgênios/farmacologia , Regulação para Baixo/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Lipoproteínas/genética , Subunidade p50 de NF-kappa B/antagonistas & inibidores , Testosterona/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Células Cultivadas , Combinação de Medicamentos , Endotélio Vascular/metabolismo , Humanos , Recém-Nascido , Lipoproteínas/metabolismo , Subunidade p50 de NF-kappa B/genética , RNA Mensageiro/metabolismo
19.
Front Oncol ; 9: 477, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249806

RESUMO

Background/Aims: Recently, rapidly accumulating evidence has shown that microRNAs (miRNAs) are involved in human tumorigenesis, and the dysregulation of miRNAs has been observed in many cancers, including prostate cancer. miR-145-5p, an miRNA with reduced expression in prostate cancer cells, has been shown to have a tumor suppressive role in a variety of tumors. However, its underlying mechanism requires further elucidation. Methods: A lentiviral expression vector for miR-145-5p was constructed and used to establish a stable cell line (LNCaP) expressing miR-145-5p. The cells were cultured normally and divided into the control group (control), negative control group (negative control), and test group (miR-145-5p). Inhibition of proliferation was measured by a WST-8 assay. The early apoptosis rate of cells was detected by flow cytometry. Clone formation ability was detected by a clone formation inhibition test. Cell invasion and migration capacity was detected by a Transwell assay. The relative expression levels of proteins were detected by western blotting. We constructed a nude mouse model of prostate cancer to observe the effect of miR-145-5p on the growth of transplanted tumors. TargetScan bioinformatics software was used to predict target genes regulated by miR-14-5p. ChIPBase was used to predict transcription factors with binding sites in the upstream promoter region of miR-145-5p. Quantitative reverse transcription PCR was used to detect the relative expression level of genes. A bifluorescence-reporter gene vector was constructed to confirm the regulation of target genes by miR-145-5p. We used 5' rapid amplification of cDNA ends to confirm the transcription start site of miR-145-5p.Chromatin immunoprecipitation technology was used to detect the effect of transcription factors binding to miR-145-5p. Results: The overexpression of miR-145-5p not only inhibited the proliferation, invasion, and migration of LNCaP cells but also promoted their early apoptosis. After overexpressing miR-145-5p, the expression of small ubiquitin-like modifier protein-specific protease 1 (SENP1), and caudal-related homeobox 2 (CDX2) protein was decreased in LNCaP cells. The transcription factor CDX2 bound to the miR-145-5p promoter region and inhibited its transcription. The transcription start site of miR-145-5p was located at a guanine residue 1,408 bp upstream of the stem-loop sequence. Upon overexpression, miR-145-5p could bind to the 3'-untranslated region of SENP1 to inhibit its translation. Conclusion: These results suggested that CDX2 inhibits the expression of miR-145-5p, thereby relieving the inhibitory effect of miR-145-5p on the translation of SENP1 and affecting the invasion and migration of prostate cancer cells.

20.
J Hypertens ; 26(6): 1119-26, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18475149

RESUMO

BACKGROUND: Urotensin II is a new potent vasoconstrictor. Nevertheless, little is known about its effects on the activation of adventitial fibroblasts. OBJECTIVE: To explore the effects of urotensin II on phenotypic differentiation, migration, and collagen I synthesis of rat aortic adventitial fibroblasts. METHODS: Growth-arrested adventitial fibroblasts were incubated in serum-free medium with urotensin II and some inhibitors of signal transduction pathways. The alpha-smooth muscle-actin expression, collagen I synthesis and migration of adventitial fibroblasts induced by urotensin II were evaluated by western blot, enzyme-linked immunosorbant assay, and the transwell technique, respectively. RESULTS: Urotensin II induced the [alpha]-smooth muscle-actin expression in a dose-dependent and time-dependent manner, with maximal effect at a concentration of 10(-8) mol/l at 24 h (79.9%); it also caused a dose-dependent increase in collagen I synthesis, with maximal effect at a concentration of 10(-7) mol/l (42.6%). The Ca2+ channel blocker nicardipine (10(-5) mol/l), protein kinase C inhibitor H7 (10(-5) mol/l), Rho protein kinase inhibitor Y-27632 (10(-5) mol/l), calcineurin inhibitor cyclosporine A (10(-5) mol/l), and mitogen-activated protein kinase inhibitor PD98059 (10(-5) mol/l) inhibited urotensin II-induced increases in [alpha]-smooth muscle-actin expression and collagen synthesis. Meanwhile, urotensin II stimulated the migration of adventitial fibroblasts dose dependently, with maximal effect at a concentration of 10(-8) mol/l, which was 5.7-fold greater than that of the control. This effect could also be inhibited by PD98059, H7, cyclosporine A, and Y-27632 but not nicardipine. CONCLUSION: Urotensin II may stimulate adventitial fibroblasts phenotypic conversion, migration, and collagen I synthesis through the protein kinase C, mitogen-activated protein kinase, calcineurin, Rho kinase, and/or Ca2+ signal transduction pathways, contributing to the development of vascular remodeling through adventitial fibroblasts activation.


Assuntos
Diferenciação Celular/fisiologia , Movimento Celular/fisiologia , Colágeno Tipo I/biossíntese , Fibroblastos/fisiologia , Urotensinas/fisiologia , Animais , Aorta/citologia , Calcineurina/metabolismo , Sinalização do Cálcio/fisiologia , Células Cultivadas , Fibroblastos/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fenótipo , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Doenças Vasculares/fisiopatologia , Quinases Associadas a rho/metabolismo
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