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1.
Langmuir ; 40(32): 16713-16721, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39074038

RESUMO

To facilitate effective training for freestyle skiers on artificial dry ski slopes, it is crucial to reduce the friction coefficient of the slopes and closely match it with that of snow. Traditional lubrication methods, such as water or soapy water, come with multiple disadvantages, including water waste, which leads to environmental pollution, short-lived effectiveness, and high costs. In this study, we have successfully developed a method for the scalable preparation of a liquid-infused coating (LIC) by tandem spraying inexpensive and environmentally friendly SiO2 particles and silicone oil lubricants. Experimental results showed that the resulting LIC is capable of imparting slippery properties to various surfaces, regardless of the surface chemistry. Moreover, the presence of LIC could reduce the friction coefficient significantly. By carefully regulating the surface composition, we achieved a friction coefficient of 0.059 between a snowboard and the LIC-functionalized ski slope, closely matching that between the snowboard and snow in a typical skiing competition venue (∼0.06). We successfully applied LIC onto 103 m2 dry ski slopes, providing a training ground for professional freestyle skiers.

2.
Langmuir ; 39(38): 13534-13545, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37712535

RESUMO

Poly(l-lactic acid) (PLLA) has been extensively utilized as a biomaterial for various biomedical applications. The first and one of the most critical steps upon contact with biological fluids is the adsorption of proteins on the material's surface. Understanding the behavior of protein adsorption is vital for guiding the synthesis and preparation of PLLA for biomedical purposes. In this study, total internal reflection fluorescence microscopy was employed to investigate the adsorption of human serum albumin (HSA) on PLLA films with different molar masses. We found that molar mass affects HSA adsorption in such a way that it affects only the adsorption rate constants, but not the desorption rate constants. Additionally, we observed that HSA adsorption is spatially heterogeneous and exhibits many strong binding sites regardless of the molar mass of the PLLA films. We found that the free volume of PLLA plays a crucial role in determining its water uptake capacity and surface hydration, consequently impacting the adsorption of HSA.


Assuntos
Poliésteres , Albumina Sérica Humana , Humanos , Adsorção , Peso Molecular
3.
J Med Internet Res ; 24(6): e37623, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35671411

RESUMO

BACKGROUND: During global health crises such as the COVID-19 pandemic, rapid spread of misinformation on social media has occurred. The misinformation associated with COVID-19 has been analyzed, but little attention has been paid to developing a comprehensive analytical framework to study its spread on social media. OBJECTIVE: We propose an elaboration likelihood model-based theoretical model to understand the persuasion process of COVID-19-related misinformation on social media. METHODS: The proposed model incorporates the central route feature (content feature) and peripheral features (including creator authority, social proof, and emotion). The central-level COVID-19-related misinformation feature includes five topics: medical information, social issues and people's livelihoods, government response, epidemic spread, and international issues. First, we created a data set of COVID-19 pandemic-related misinformation based on fact-checking sources and a data set of posts that contained this misinformation on real-world social media. Based on the collected posts, we analyzed the dissemination patterns. RESULTS: Our data set included 11,450 misinformation posts, with medical misinformation as the largest category (n=5359, 46.80%). Moreover, the results suggest that both the least (4660/11,301, 41.24%) and most (2320/11,301, 20.53%) active users are prone to sharing misinformation. Further, posts related to international topics that have the greatest chance of producing a profound and lasting impact on social media exhibited the highest distribution depth (maximum depth=14) and width (maximum width=2355). Additionally, 97.00% (2364/2437) of the spread was characterized by radiation dissemination. CONCLUSIONS: Our proposed model and findings could help to combat the spread of misinformation by detecting suspicious users and identifying propagation characteristics.


Assuntos
COVID-19 , Mídias Sociais , Comunicação , Humanos , Pandemias , SARS-CoV-2
4.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(9): 994-1000, 2022.
Artigo em Zh | MEDLINE | ID: mdl-36111717

RESUMO

OBJECTIVES: To study the changes in the mortality rate and cause of death of hospitalized neonates in grade A tertiary hospitals in Weifang City of Shandong Province during a 10-year period. METHODS: A retrospective analysis was performed on 461 neonates who died in three grade A tertiary hospitals in Weifang City of Shandong Province from January 1, 2012 to December 31, 2021. The related clinical data were collected to examine the changes of neonatal mortality with time, gestational age (GA) and birth weight (BW). The main causes of death of the neonates were compared between the first 5 years (2012-2016) and the last 5 years (2017-2021) in the period. RESULTS: A total of 43 037 neonates were admitted from 2012 to 2021, among whom 461 died, resulting in a mortality rate of 1.07%. The mortality rate in the last 5 years was significantly lower than that in the first 5 years [0.96% (211/22 059 vs 1.19% (250/20 978); P<0.05]. The mortality rate of neonates decreased with the increases in GA and BW (P<0.05). In the first 5 years, the top three main causes of neonatal death were respiratory distress syndrome (RDS), sepsis, and pneumorrhagia, while in the last 5 years, the top three causes were sepsis, pneumorrhagia, and RDS. The leading cause of death was severe asphyxia for the neonates with a GA of <26 weeks and a BW of <750 g in both the first and last 5 years. For the neonates with a GA of 26-<28 weeks, the leading cause of death changed from RDS in the first 5 years to pneumorrhagia in the last 5 years. For the neonates with a BW of 750-<1 000 g, the leading cause of death changed from pneumorrhagia in the first 5 years to RDS in the last 5 years. For the neonates with a GA of 28-<32 weeks and a BW of 1 000-<1 500 g, the leading cause of death was RDS in both the first and last 5 years. For the neonates with a GA of 32-<37 weeks and a BW of 1 500-<2 500 g, the leading cause of death changed from RDS in the first 5 years to sepsis in the last 5 years. The leading cause of death was sepsis for the neonates with a GA of 37-<42 weeks and a BW of 2 500-<4 000 g in both the first and last 5 years. CONCLUSIONS: The mortality rate of neonates in the grade A tertiary hospitals in Weifang City of Shandong Province has been decreasing in the past 10 years, and it decreases with the increases in GA and BW. Sepsis, RDS, and pneumorrhagia are the leading causes of neonatal death. The mortality rate caused by RDS decreases from the first 5 years to the last 5 years, while the mortality rate caused by sepsis or pneumorrhagia increases from the first 5 years to the last 5 years. Therefore, reducing the incidence rates of sepsis, RDS, and pneumorrhagia is the key to reducing neonatal mortality.


Assuntos
Morte Perinatal , Síndrome do Desconforto Respiratório do Recém-Nascido , Sepse , Peso ao Nascer , Causas de Morte , Feminino , Humanos , Recém-Nascido , Estudos Retrospectivos
5.
Biochem Biophys Res Commun ; 551: 78-85, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33735626

RESUMO

Circular RNAs (circRNAs) and microRNAs (miRNAs) have been emerging as new players in acute myeloid leukemia (AML). Hsa_circ_0005774 (circ_0005774) is an upregulated circRNA in pediatric AML, while its role is uncovered. Thus, we intended to measure the function and mechanism of circ_0005774 in AML leukemogenesis. Real time-quantitative PCR revealed that circ_0005774 was highly expressed in blood of pediatric AML patients and AML cells (HL-60 and NB4), accompanied with downregulated miRNA-192-5p (miR-192-5p) which was a crucial tumor-associated and leukemia-related miRNA. Circ_0005774 was abundant in miRNA response element according to CSCD software, and miR-192-5p was identified as a target of circ_0005774, as evidenced by RNA immunoprecipitation and dual-luciferase reporter assays. Cell viability assay, flow cytometry and western blotting were performed to measure cell functions. Accordingly, blocking circ_0005774 and/or overexpressing miR-192-5p could enhance apoptosis rate of HL-60 and NB4 cells, but suppress cell viability and cell cycle entrance, accompanied with depression of proliferation markers including proliferating cell nuclear antigen (PCNA), CyclinD1 and B cell lymphoma 2 (Bcl-2). Meanwhile, depleting miR-192-5p counteracted the role of circ_0005774 knockdown in AML cells. Uncoordinated 51-like kinase 1 (ULK1) was previously demonstrated to be associated with diagnosis, prognosis and therapeutic strategy for AML, and restoring ULK1 could abrogate miR-192-5p overexpression-induced effects in HL-60 and NB4 cells. Notably, ULK1 was a downstream target of miR-192-5p and indirectly modulated by circ_0005774. In conclusion, circ_0005774 knockdown repressed cell proliferation and promoted apoptosis of AML cells partially through regulating miR-192-5p/ULK1 axis.


Assuntos
Apoptose , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Leucemia Mieloide Aguda/sangue , Leucemia Mieloide Aguda/patologia , MicroRNAs/genética , RNA Circular/sangue , RNA Circular/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Criança , Pré-Escolar , Feminino , Técnicas de Silenciamento de Genes , Inativação Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Masculino , RNA Circular/deficiência , Regulação para Cima
6.
Langmuir ; 37(41): 12118-12127, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34610245

RESUMO

Emulsions stabilized by both nanoparticles and surfactants often display longer shelf life than those stabilized by nanoparticles or surfactants alone. Although numerous works have been conducted to understand the effect of nanoparticles and surfactants on the variation of interfacial tension, little is known about interfacial diffusion when both nanoparticles and surfactants are present at interfaces. In this work, we used single-particle fluorescence tracking to study the lateral diffusion of individual hydrophobic nanoparticles at hexane-glycerol interfaces adsorbed by different amounts of nonionic surfactants. When the surfactant concentration is over a threshold, we found that the nanoparticle diffusion exhibits a two-regime behavior involving short-time Brownian and the emergence of subdiffusive, non-Gaussian, and dynamically anticorrelated diffusion in the long lag time regime. A stepwise analysis rationalized diffusion in different lag time regimes, leading to a mechanistic interpretation regarding the two-regime behavior. These results could provide insight into the understanding of the synergistic effect for the surfactant-assistant Pickering emulsion.

7.
Neurochem Res ; 45(12): 2840-2855, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33000435

RESUMO

Circular RNAs (circRNAs) played pivotal roles in the initiation and progression of cancers. CircRNA cut like homeobox 1 (circ-CUX1; hsa_circ_0132813) has been reported to contribute to neuroblastoma (NB) development by previous study. Furthermore, previous works reported that microRNA-16-5p (miR-16-5p) was down-regulated while doublesex and mab-3 related transcription factor 2 (DMRT2) was up-regulated in NB. The interaction and functional association between miR-16-5p and circ-CUX1 or DMRT2 were investigated in this study. Cell proliferation, cell cycle progression, colony formation, migration and invasion of NB cells were examined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, colony formation assay and transwell migration and invasion assays. The glycolysis was analyzed through measuring the consumption of glucose and the production of lactate and ATP. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP) assay and RNA-pull down assay were utilized to confirm the interaction between miR-16-5p and circ-CUX1 or DMRT2. Tumor xenograft assay was performed to explore the function of circ-CUX1 in xenograft tumor growth in vivo. Circ-CUX1 promoted the proliferation, migration, invasion and glycolysis of NB cells. miR-16-5p was a direct target of circ-CUX1, and miR-16-5p overexpression-mediated effects in NB cells were partly alleviated by the introduction of circ-CUX1 overexpression plasmid. DMRT2 was a target of miR-16-5p in NB cells, and the introduction of anti-miR-16-5p overturned the influences of DMRT2 interference on the proliferation, migration and invasion and glycolysis of NB cells. Circ-CUX1 silencing restrained xenograft tumor growth in vivo. In conclusion, circ-CUX1 accelerated the proliferation, migration, invasion and glycolysis of NB cells through targeting miR-16-5p/DMRT2 signaling cascade.


Assuntos
Proteínas de Ligação a DNA/metabolismo , MicroRNAs/metabolismo , Neuroblastoma/fisiopatologia , RNA Circular/metabolismo , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Pré-Escolar , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Glicólise/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos Endogâmicos BALB C , Neuroblastoma/genética , Neuroblastoma/metabolismo
8.
Neurochem Res ; 45(11): 2679-2690, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32857295

RESUMO

Neuroblastoma (NB) is a heterogeneous tumor that is common in infants and young children. Long non-coding RNA X-inactive specific transcript (XIST) is implicated in NB advancement. Nevertheless, the role and regulatory mechanism by which XIST in NB are not fully elucidated. Expression levels of XIST, microRNA-375-5p (miR-375), and L1 cell adhesion molecular (L1CAM) were examined through quantitative real-time polymerase chain reaction (qRT-PCR). The cell cycle progression, proliferation, and colony formation of NB cells were determined with flow cytometry, 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), or cell colony formation assays. Cell apoptotic rate was detected with flow cytometry assay. The relationship between XIST or L1CAM and miR-375 was verified via dual-luciferase reporter assay. The level of L1CAM protein was examined through western blotting. The role of XIST in vivo was confirmed through xenograft assay. XIST and L1CAM were upregulated while miR-375 was downregulated in NB tissues and cells. XIST depletion repressed tumor growth in vivo and elevated radiosensitivity, arrested cell cycle progression, and impeded proliferation of NB cells in vitro. Mechanistically, XIST modulated L1CAM expression through competitively binding to miR-375. Furthermore, miR-375 inhibitor recovered XIST inhibition-mediated effects on the radiosensitivity and malignant behaviors of NB cells. Also, L1CAM overexpression reversed the effects of miR-375 enhancement on the cell cycle progression, proliferation, and radiosensitivity of NB cells. XIST downregulation repressed tumor growth and boosted radiosensitivity of NB via modulating the miR-375/L1CAM axis, indicating that XIST was a promising target for NB treatment.


Assuntos
Proliferação de Células/fisiologia , MicroRNAs/metabolismo , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Neuroblastoma/fisiopatologia , RNA Longo não Codificante/genética , Tolerância a Radiação/fisiologia , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , RNA Longo não Codificante/metabolismo , Regulação para Cima
9.
BMC Pediatr ; 20(1): 321, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32600275

RESUMO

BACKGROUND: The objective of this prospective, multicentre, observational cohort study was to evaluate the association between admission hypothermia and neonatal outcomes in very low-birth weight (VLBW) infants in multiple neonatal intensive care units (NICUs) in China. METHODS: Since January 1, 2018, a neonatal homogeneous cooperative research platform-Shandong Neonatal Network (SNN) has been established. The platform collects clinical data in a prospective manner on preterm infants with birth weights (BWs) < 1500 g and gestational ages (GAs) < 34 weeks born in 28 NICUs in Shandong Province. These infants were divided into normothermia, mild or moderate/severe hypothermia groups according to the World Health Organization (WHO) classifications of hypothermia. Associations between outcomes and hypothermia were tested in a bivariate analysis, followed by a logistic regression analysis. RESULTS: A total of 1247 VLBW infants were included in this analysis, of which 1100 infants (88.2%) were included in the hypothermia group, 554 infants (44.4%) in the mild hypothermia group and 546 infants (43.8%) in the moderate/severe hypothermia group. Small for gestational age (SGA), caesarean section, a low Apgar score at 5 min and intubation in the delivery room (DR) were related to admission hypothermia (AH). Mortality was the lowest when their admission temperature was 36.5 ~ 37.5 °C, and after adjustment for maternal and infant characteristics, mortality was significantly associated with AH. Compared with infants with normothermia (36.5 ~ 37.5 °C), the adjusted ORs of all deaths increased to 4.148 (95% CI 1.505-11.437) and 1.806 (95% CI 0.651-5.009) for infants with moderate/severe hypothermia and mild hypothermia, respectively. AH was also associated with a high likelihood of respiratory distress syndrome (RDS), intraventricular haemorrhage (IVH), and late-onset neonatal sepsis (LOS). CONCLUSIONS: AH is still very high in VLBW infants in NICUs in China. SGA, caesarean section, a low Apgar score at 5 min and intubation in the DR were associated with increased odds of hypothermia. Moderate/severe hypothermia was associated with mortality and poor outcomes, such as RDS, IVH, LOS.


Assuntos
Hipotermia , Cesárea , China/epidemiologia , Feminino , Humanos , Hipotermia/epidemiologia , Hipotermia/etiologia , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Unidades de Terapia Intensiva Neonatal , Gravidez , Estudos Prospectivos
10.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(8): 830-835, 2019 Aug.
Artigo em Zh | MEDLINE | ID: mdl-31416511

RESUMO

OBJECTIVE: To study the effects of different melatonin treatment regimens on the proliferation of neural stem cells (NSCs) and long-term histopathology in neonatal rats with hypoxic-ischemic brain damage (HIBD), and to identify better melatonin treatment regimens. METHODS: A total of 96 Sprague-Dawley rats aged 7 days were randomly divided into normal control, HIBD, single-dose immediate melatonin treatment (SDIT), and 7-day continuous melatonin treatment (7DCT) groups, with 24 rats in each group. The rat model of HIBD was prepared by isolation and electrocoagulation of the right common carotid artery as well as hypoxic treatment in a hypoxic chamber (oxygen concentration 8.00% ±â€…0.01%) for 2 hours. On day 7 after modeling, proliferating cell nuclear antigen/Nestin double-labeling immunofluorescence was used to measure the proliferation of endogenous NSCs in the subventricular zone (SVZ) and the hippocampal dentate gyrus (DG) region in 8 rats in each group, and Western blot was used to measure the protein expression of Nestin in brain. On day 28 after modeling, hematoxylin-eosin (HE) staining and Nissl staining were used to observe the changes in the histopathology and the number of pyramidal cells in the hippocampal CA1 region in 8 rats in each group. RESULTS: Immunofluorescent staining showed that compared with the HIBD group, the SDIT and 7DCT groups had a significant increase in the number of PCNA+Nestin+DAPI+ cells, and the 7DCT group had a significantly higher number than the SDIT group (P<0.01). Western blot showed that the SDIT and 7DCT groups had significantly higher protein expression of Nestin than the HIBD group, and the 7DCT group had significantly higher expression than the SDIT group (P<0.05). HE staining showed that the SDIT and 7DCT groups had alleviated cell injury, and Nissl staining showed that compared with the HIBD group, the SDIT and 7DCT groups had a significant increase in the number of pyramidal cells, and the 7DCT group had a significantly higher number than the SDIT group (P<0.01). CONCLUSIONS: Both single-dose immediate melatonin treatment and 7-day continuous melatonin treatment can promote the proliferation of endogenous NSCs and alleviate long-term histological injury in the brain of neonatal rats with HIBD. A 7-day continuous melatonin treatment has a better effect than single-dose immediate melatonin treatment.


Assuntos
Hipóxia-Isquemia Encefálica , Células-Tronco Neurais , Animais , Animais Recém-Nascidos , Encéfalo , Proliferação de Células , Melatonina , Neurônios , Ratos , Ratos Sprague-Dawley
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 20(3): 174-177, 2018 Mar.
Artigo em Zh | MEDLINE | ID: mdl-29530114

RESUMO

OBJECTIVE: To study the risk factors for elevated serum total bile acid (TBA) in preterm infants. METHODS: A retrospective analysis was performed for the clinical data of 216 preterm infants who were admitted to the neonatal intensive care unit. According to the presence or absence of elevated TBA (TBA >24.8 µmol/L), the preterm infants were divided into elevated TBA group with 53 infants and non-elevated TBA group with 163 infants. A univariate analysis and an unconditional multivariate logistic regression analysis were used to investigate the risk factors for elevated TBA. RESULTS: The univariate analysis showed that there were significant differences between the elevated TBA group and the non-elevated TBA group in gestational age at birth, birth weight, proportion of small-for-gestational-age infants, proportion of infants undergoing ventilator-assisted ventilation, fasting time, parenteral nutrition time, and incidence of neonatal respiratory failure and sepsis (P<0.05). The unconditional multivariate logistic regression analysis showed that low birth weight (OR=3.84, 95%CI: 1.53-9.64) and neonatal sepsis (OR=2.56, 95%CI: 1.01-6.47) were independent risk factors for elevated TBA in preterm infants. CONCLUSIONS: Low birth weight and neonatal sepsis may lead to elevated TBA in preterm infants.


Assuntos
Ácidos e Sais Biliares/sangue , Recém-Nascido Prematuro/sangue , Feminino , Humanos , Recém-Nascido de Baixo Peso/sangue , Recém-Nascido , Modelos Logísticos , Masculino , Estudos Retrospectivos , Fatores de Risco , Sepse/sangue
12.
Mol Genet Genomics ; 292(4): 833-846, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28357596

RESUMO

Alu elements in the human genome are present in more than one million copies, accounting for 10% of the genome. However, the biological functions of most Alu repeats are unknown. In this present study, we detected the effects of Alu elements on EGFP gene expression using a plasmid system to find the roles of Alu elements in human genome. We inserted 5'-4TMI-Alus-CMV promoter-4TMI-Alus (or antisense Alus)-3' sequences into the pEGFP-C1 vector to construct expression vectors. We altered the copy number of Alus, the orientation of the Alus, and the presence of an enhancer (4TMI) in the inserted 5'-4TMI-Alus-CMV promoter-4TMI-Alus (or antisense Alus)-3' sequences. These expression vectors were stably transfected into HeLa cells, and EGFP reporter gene expression was determined. Our results showed that combined sense-antisense Alu elements activated the EGFP reporter gene in the presence of enhancers and stable transfection. The combined sense-antisense Alu vectors carrying four copies of Alus downstream of inserted CMV induced much stronger EGFP gene expression than two copies. Alus downstream of inserted CMV were replaced to AluJBs (having 76% homology with Alu) to construct expression vectors. We found that combined sense-antisense Alu (or antisense AluJB) vectors induced strong EGFP gene expression after stable transfection and heat shock. To further explore combined sense-antisense Alus activating EGFP gene expression, we constructed Tet-on system vectors, mini-C1-Alu-sense-sense and mini-C1-Alu-sense-antisense (EGFP gene was driven by mini-CMV). We found that combined sense-antisense Alus activated EGFP gene in the presence of reverse tetracycline repressor (rTetR) and doxycycline (Dox). Clone experiments showed that Mini-C1-Alu-sense-antisense vector had more positive cells than that of Mini-C1-Alu-sense-sense vector. The results in this paper proved that Alu repetitive sequences inhibited gene expression and combined sense-antisense Alus activated EGFP reporter gene when Alu transcribes, which suggests that Alus play roles in maintaining gene expression (silencing genes or activating genes) in human genome.


Assuntos
Elementos Alu/genética , Elementos Antissenso (Genética)/genética , Regulação da Expressão Gênica/genética , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Sequências Reguladoras de Ácido Nucleico/genética , Linhagem Celular Tumoral , Dosagem de Genes/genética , Genoma Humano , Células HeLa , Humanos , Regiões Promotoras Genéticas , Ativação Transcricional/genética , Transfecção
13.
Microb Cell Fact ; 16(1): 183, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29084536

RESUMO

BACKGROUND: Exogenous RNAs can specifically up-regulate or down-regulate gene expression after they enter into cells. Alu RNAs are the main constituent of human transcriptome and participate in gene expression regulation. AluY elements belong to a subfamily of Alus and are the youngest Alus. In this paper, we established the technology method of preparing genetically engineered humanized AluY RNAs (AluY RNAs) from Escherichia coli (E. coli) strains. This technology method also can be used to prepare other genetically engineered humanized RNAs that can be used for cytology experiments. RESULTS: Different copies of human AluY elements were inserted into pET-28α plasmid (pET) to construct pET-AluY plasmids that were transformed into BMBL21-DE3 (DE3) E. coli. Isopropylthio-ß-D-galactoside (IPTG) induction inhibited transformed bacterial growth after DE3 E. coli were transformed by pET-AluY × 8 plasmid (8 copies of AluYs were inserted into pET); northern blotting was used to detect the amount of AluY RNAs after 2, 4, 6, 8, 10, 12, 14 and 16 h inducing with IPTG. The results showed that the amount of AluY RNAs was the highest at 4 h; 1, 2, 4, 8 or 14 copies of AluY elements were inserted into the pET to construct pET-AluY plasmids that were transformed into DE3 bacteria, the northern blotting results showed that AluY RNAs production amount increased with the increase of AluY copy number; pET-AluY × 8 DE3 bacteria did not produce AluY RNAs without IPTG induction, AluY RNA production kept similar when inducing by 0.1-0.4 mg/ml IPTG induction, however, AluY RNA production slightly decreased if deviating from the above concentration range; pET-AluY × 8 DE3 bacteria were cultured at 34, 37 or 40 °C and the results showed that AluY RNA production was the highest under 37 °C cultivation; pET-AluY × 8 plasmid was transformed into three kinds of BL21 bacteria, including DE3, BMBL21-DE3-pLysS (pLysS) and Trans BL 21 (TransBL), the results showed that AluY RNA production was the highest when using DE3 bacteria. CONCLUSIONS: The optimal conditions of producing AluY RNAs were: a kind of host bacteria of DE3, an engineering bacteria concentration of OD600 1.0, an IPTG concentration of 0.2 mg/ml, a culturing temperature of 37 °C and a culturing time of 4 h. Pure AluY RNAs occupied 15.8% of extractive total RNAs and the mean yield of pure AluY RNAs in 100 ml bacteria solution was 0.46 mg.


Assuntos
Elementos Alu/genética , Escherichia coli/metabolismo , Engenharia Genética , RNA/metabolismo , Desoxirribonuclease I/metabolismo , Escherichia coli/crescimento & desenvolvimento , Humanos , Plasmídeos/genética , Plasmídeos/metabolismo , Ribonuclease Pancreático/metabolismo
14.
Health Info Libr J ; 34(4): 268-283, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29045011

RESUMO

OBJECTIVE: The objective of this literature review was to summarise current research regarding how consumers seek health-related information from social media. Primarily, we hope to reveal characteristics of existing studies investigating the health topics that consumers have discussed in social media, ascertaining the roles social media have played in consumers' information-seeking processes and discussing the potential benefits and concerns of accessing consumer health information in social media. METHODS: The Web of Science Core Collection database was searched for existing literature on consumer health information seeking in social media. The search returned 214 articles, of which 21 met the eligibility criteria following review of full-text documents. CONCLUSION: Between 2011 and 2016, twenty-one studies published explored various topics related to consumer information seeking in social media. These ranged from online discussions on specific diseases (e.g. diabetes) to public health concerns (e.g. pesticide residues). Consumers' information needs vary depending on the health issues of interest. Benefits of health seeking on social media, in addition to filling a need for health information, include the social and emotional support health consumers gain from peer-to-peer interactions. These benefits, however, are tempered by concerns of information quality and authority and lead to decreased consumer engagement.


Assuntos
Informação de Saúde ao Consumidor/normas , Comportamento de Busca de Informação , Mídias Sociais/estatística & dados numéricos , Informação de Saúde ao Consumidor/métodos , Humanos , Internet
15.
Zhongguo Dang Dai Er Ke Za Zhi ; 19(11): 1202-1207, 2017 Nov.
Artigo em Zh | MEDLINE | ID: mdl-29132470

RESUMO

OBJECTIVE: To explore the effects of rat bone mesenchymal stem cell (BMSC) transplantation on retinal neovascularization, and to observe the changes of hypoxia-inducible factor-1 alpha (HIF-1α) and vascular endothelial growth factors (VEGF) in rats with oxygen-induced retinopathy (OIR). METHODS: Seventy-two seven-day-old Sprague-Dawley rats were randomly divided into three groups: normal control (CON), model (OIR) and BMSC transplantation. In the BMSC transplantation group, BMSCs were transplanted 5 days after oxygen conditioning. The phosphate buffered saline of the same volume was injected in the CON and OIR groups. The OIR model was prerpared according to the classic hyperoxygen method. At seven days after transplantation, retinal neovascularization was examined by retinal flat-mount staining and hematoxylin eosin (HE) staining. The expression of HIF-1α and VEGF proteins was examined by immunohistochemistry staining and Western blot analysis. RESULTS: The retinal flat-mount staining results showed that the vessels were well organized in the CON group, but the vessels were irregularly organized, and lots of nonperfusion areas were observed in the OIR group. The large vessels were a bit circuitous, the retinal vessels were relatively organized, and less nonperfusion areas were noted in the BMSC transplantation group. The HE staining results showed that many neovessels and preretinal neovascular (pre-RNC) cells were observed on the internal limiting membrane in the OIR group. There were less pre-RNC cells in the BMSC transplantation group compared with the OIR group (P<0.01). The immunohistochemistry analysis showed that more HIF-1α+ and VEGF+ cells were observed in the OIR group compared with the CON group, and less HIF-1α+ and VEGF+ cells were observed in the BMSC transplantation group compared with OIR group (P<0.05). The Western blot analysis showed the expression of HIF-1α and VEGF proteins in the OIR group was significantly higher than that in the CON group. The expression of HIF-1α and VEGF proteins in the BMSC transplantation group was lower than that in the OIR group (P<0.01). CONCLUSIONS: BMSC transplantation therapy could alleviate retinal neovascularization in OIR rats, and its mechanisms might be associated with the inhibition of the expression of HIF-1α and VEGF proteins.


Assuntos
Transplante de Células-Tronco Mesenquimais , Neovascularização Retiniana/prevenção & controle , Retinopatia da Prematuridade/terapia , Animais , Animais Recém-Nascidos , Feminino , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Masculino , Ratos , Ratos Sprague-Dawley , Retina/química , Retinopatia da Prematuridade/metabolismo , Fator A de Crescimento do Endotélio Vascular/análise
16.
Biochem Biophys Res Commun ; 472(3): 557-65, 2016 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-26970302

RESUMO

Osteosarcoma is an aggressive primary sarcoma of bone and occurs mainly in adolescents and young adults. The prognosis of OS remains poor, and most of them will die due to local relapse or metastases. The discovery of microRNAs provides a new possibility for the early diagnosis and treatment of OS. Thus, the aim of this study was to explore the expression and functions of microRNA-198 (miR-198) in osteosarcoma. The expression levels of miR-198 were determined by qRT-PCR in osteosarcoma tissues and cell lines. Cell proliferation assays, migration and invasion assays were adopted to investigate the effects of miR-198 on tumorous behaviors of osteosarcoma cells. The results showed that miR-198 expression levels were lower in osteosarcoma tissues and cell lines. In addition, low miR-198 expression levels were correlated with TNM stage and distant metastasis. After miR-198 mimics transfection, cell proliferation, migration and invasion were significantly suppressed in the osteosarcoma cells. Furthermore, ROCK1 was identified as a novel direct target of miR-198 in osteosarcoma. These findings suggested that miR-198 may act not only as a novel prognostic marker, but also as a potential target for molecular therapy of osteosarcoma.


Assuntos
MicroRNAs/metabolismo , Osteossarcoma/metabolismo , Osteossarcoma/secundário , Quinases Associadas a rho/metabolismo , Linhagem Celular Tumoral , Humanos , Estadiamento de Neoplasias , Osteossarcoma/patologia
17.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(5): 435-9, 2015 May.
Artigo em Zh | MEDLINE | ID: mdl-26014690

RESUMO

OBJECTIVE: To study the diagnostic value and influencing factors for amplitude-integrated EEG (aEEG) in brain injury in preterm infants. METHODS: One hundred and sixteen preterm infants with a gestational age (GA) between 27 weeks and 36(+6) weeks were enrolled as subjects. The aEEG scores of all preterm infants were obtained within 6 hours after birth. According to the diagnostic results, the 116 preterm infants were divided into two groups: brain injury (n=63) and non-brain injury (n=53). The risk factors for brain injury were evaluated using logistic regression analysis. According to the aEEG results, the 116 preterm infants were divided into two groups: normal aEEG (n=58) and abnormal aEEG (n=58). The influencing factors for aEEG results in preterm infants were determined using univariate analysis. RESULTS: The brain injury group had a significantly higher rate of abnormal aEEG than the non-brain injury group (83% vs 11%; P<0.05). The infants in the brain injury group from two different GA subgroups (27-33(+6) weeks and 34-36(+6) weeks) had significantly lower aEEG scores than the non-brain injury group from corresponding GA subgroups (P<0.01). Logistic regression analysis showed that low GA (<32 weeks), low birth weight (<1 500 g), abnormal placenta, fetal membranes, and umbilical cord, and hypertension during pregnancy were high-risk factors for brain injury (P<0.05). There were significant differences in GA, birth weight, abnormal placenta, fetal membranes, and umbilical cord, and hypertension during pregnancy between the normal and abnormal aEEG groups (P<0.05). CONCLUSIONS: The risk factors for brain injury are consistent with the influencing factors for aEEG results in preterm infants, suggesting that aEEG contributes to the early diagnosis of brain injury.


Assuntos
Lesões Encefálicas/fisiopatologia , Eletroencefalografia , Peso ao Nascer , Lesões Encefálicas/diagnóstico , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Modelos Logísticos , Gravidez , Fatores de Risco
18.
Digit Health ; 10: 20552076241277171, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39224794

RESUMO

Objective: The COVID-19 pandemic has spurred an increased interest in online healthcare and a surge in usage of online healthcare platforms, leading to a proliferation of user-generated online physician reviews. Yet, distinguishing between genuine and fake reviews poses a significant challenge. This study aims to address the challenges delineated above by developing a reliable and effective fake review detection model leveraging deep learning approaches based on a fake review dataset tailored to the context of Chinese online medical platforms. Methods: Inspired by prior research, this paper adopts a crowdsourcing approach to assemble the fake review dataset for Chinese online medical platforms. To develop the fake review detection models, classical machine learning models, along with deep learning models such as Convolutional Neural Network and Bidirectional Encoder Representations from Transformers, were applied. Results: Our experimental deep learning model exhibited superior performance in identifying fake reviews on online medical platforms, achieving a precision of 98.36% and an F2-Score of 97.97%. Compared to the traditional machine learning models (i.e., logistic regression, support vector machine, random forest, ridge regression), this represents an 8.16% enhancement in precision and a 7.7% increase in F2-Score. Conclusion: Overall, this study provides a valuable contribution toward the development of an effective fake physician review detection model for online medical platforms.

19.
Chem Commun (Camb) ; 60(18): 2505-2508, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38333913

RESUMO

Waxgels are known for their unique ability to generate sacrificial wax layers during anti-icing. To address the severe slow regrowth of the wax layer, here, carbon black is incorporated in the waxgel network to endow photothermal function. The rate of the regrowth of the wax layer is raised by >6 times under natural light conditions. Meanwhile, the photothermal waxgel showed improved anti-icing performances in terms of delayed ice formation and lower ice adhesion strength.

20.
RSC Adv ; 14(13): 9243-9253, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38505390

RESUMO

Zeolite catalyzed alkylation of benzene with long-chain α-olefins is a promising method for the detergent industry. Considering the long-chain α-olefins from Fischer-Tropsch synthesis always contain some oxygenated organic compounds, the effect of which on the alkylation of benzene with 1-dodecene was comprehensively investigated over beta zeolite herein. n-heptanol, n-heptaldehyde and n-heptanoic acid were selected as the model oxygenated organic compounds, and it was revealed that an obvious decrease of lifetime occurred when only trace amount of oxygenated organic compounds were added into the feedstocks. The deactivated catalyst was difficult to regenerate by extraction with hot benzene or coke-burning. A series of characterization tests complementary with DFT calculations revealed that the deactivation was mainly caused by the firm adsorption of oxygenated organic compounds on the acid sites. Further, comparison with the open-framework MWW zeolite revealed a similar effect of oxygenated organic compounds and deactivation mechanism for both beta and MWW, but beta is less sensitive to the oxygenated organic compounds. The main reason lies in the three-dimensional framework of beta, wherein the much higher adsorption energy of 1-dodecene makes it difficult to be replaced by oxygenated organic compounds. Additionally, beta could be regenerated more easily by extraction with hot benzene compared with MWW. But coke-burning caused a sharp decrease of its lifetime, which is mainly due to the decreased acid sites after calcination.

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