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1.
Methods Mol Biol ; 2784: 191-200, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38502487

RESUMO

The secondary and tertiary structures of RNA play a vital role in the regulation of biological reactions. These structures have been experimentally studied through in vivo and in vitro analyses, and in silico models have become increasingly accurate in predicting them. Recent technologies have diversified RNA structure predictions, from the earliest thermodynamic and molecular dynamic-based RNA structure predictions to deep learning-based conformation predictions in the past decade. While most research on RNA structure prediction has focused on short non-coding RNAs, there has been limited research on predicting the conformation of longer mRNAs. Our study introduces a computer simulation model called the Three-dimensional RNA Illustration Program (TRIP). TRIP is based on single-chain models and angle restriction of each bead component from previously reported single-molecule fluorescence in situ hybridization (smFISH) experiments. TRIP is a fast and efficient application that only requires up to three inputs to acquire outputs. It can also provide a rough visualization of the 3D conformation of RNA, making it a valuable tool for predicting RNA end-to-end distance.


Assuntos
Simulação de Dinâmica Molecular , RNA , RNA/genética , RNA/química , Conformação de Ácido Nucleico , RNA Mensageiro/genética , Hibridização in Situ Fluorescente
2.
Gels ; 10(1)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38247770

RESUMO

Research into functional gels and chemicals and their applications represents a cutting-edge international field of study. For example, investigating how they can be applied in oil and gas drilling (and extraction engineering) and developing novel functional chemical materials for the oil field could provide innovative solutions and technological methods for oil and gas drilling and extraction operations. Through a literature analysis, this paper presents a review of the current research status and application scenarios of different types of functional gels and chemicals, both domestically and internationally. The classification and preparation principles of various functional materials are systematically outlined and the current applications of functional gels and chemicals in oil and gas drilling and extraction engineering are introduced. These applications include drilling and plugging, enhanced oil recovery, water plugging, and profile control. The formation mechanisms and application scenarios of different types of gels and chemicals are also analyzed and summarized, with a discussion of their prospects in oil and gas drilling and extraction engineering. We broaden the scope of functional gels and chemicals by exploring new application fields and promoting the development of different types of gels and chemicals in a more intelligent direction.

3.
J Mater Chem B ; 11(12): 2631-2637, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36794489

RESUMO

Based on disulfide-enriched multiblock copolymer vesicles, we present a straightforward sequential drug delivery system with dual-redox response that releases hydrophilic doxorubicin hydrochloride (DOX·HCl) and hydrophobic paclitaxel (PTX) under oxidative and reductive conditions, respectively. When compared to concurrent therapeutic delivery, the spatiotemporal control of drug release allows for an improved combination antitumor effect. The simple and smart nanocarrier has promising applications in the field of cancer therapy.


Assuntos
Dissulfetos , Sistemas de Liberação de Medicamentos , Dissulfetos/química , Paclitaxel/química , Doxorrubicina/química , Polímeros , Oxirredução
4.
Int J Biol Macromol ; 161: 1011-1020, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531368

RESUMO

As the simplest glycosaminoglycan (GAG) in extracellular matrix, hyaluronic acid (HA) takes part in several important biological processes, such as regulating cell proliferation, differentiation, and migration. In this work, a series of HA-inspired polymers with different saccharide and carboxylate units (HA-analogue polymers) are synthesized by free radical polymerization, and characterized using Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC) and nuclear magnetic resonance spectrometer (NMR), Moreover, cell experiments demonstrate that HA-analogue polymers with a certain proportion of saccharide and carboxylate (PM1G1) units shows a positive effect on the proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs). Furthermore, HA-analogue polymers have prominent cartilage inductive capacity in chondrogenic induction medium (CIM) and brilliant bone inductive capacity in osteogenic induction medium (OIM) toward BMSCs. Therefore, it is confirmed that the HA-analogue polymers can effectively mimic the functions of HA and have broad potential application prospects in the biomedical and clinical fields.


Assuntos
Biopolímeros/química , Biopolímeros/farmacologia , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Condrogênese/efeitos dos fármacos , Ácido Hialurônico/química , Osteogênese/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Técnicas de Química Sintética , Condrócitos/citologia , Humanos , Ácido Hialurônico/análogos & derivados , Espectroscopia de Infravermelho com Transformada de Fourier
5.
J Mater Chem B ; 8(26): 5655-5666, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32500905

RESUMO

Although carbon dots (CDs) have been synthesized and applied in a variety of biological fields, such as disease diagnosis and gene/drug delivery, the exploration of facile bioinspired synthesis and applications of CDs is still of great significance. Particularly, recent increasing research has clearly confirmed that nanomaterials can affect a series of physiological behaviors and functions of mesenchymal stem cells (MSCs) (e.g., differentiation and pluripotency). Therefore, it is very important to develop multifunctional nanomaterials to simultaneously realize the cellular labelling and regulation of MSC behaviors in practical applications. Herein, sulfonated glycosaminoglycan-bioinspired CDs as bi-functional nanomaterials were ingeniously designed for cellular imaging and promoting the differentiation of rat bone MSCs (rBMSCs) in different culture media, which simultaneously met the two fundamental requirements in the field of MSC-based treatments (e.g., precisely directing the differentiation of MSCs and effective cellular labeling). These bifunctional CDs were successfully prepared via one-pot hydrothermal synthesis by using d-glucosamine hydrochloride (GA·HCl) and sodium p-styrenesulfonate (NaSS) as the reactants. The synthesized CDs with a uniform particle size (around 4 nm) dispersed well in aqueous solutions and exhibited remarkable fluorescence stability under different conditions. Additionally, cell viability and proliferation results demonstrated that the CDs possessed good biocompatibility, having negligible effects on the self-renewal potential of rBMSCs. The as-prepared CDs presented a cytoplasmatic distribution after being ingested by rBMSCs; thus, they are particularly suitable for cellular imaging. More importantly, the addition of CDs to osteogenic and chondrogenic induction media (OIM and CIM), respectively, was capable of effectively promoting the osteogenic and chondrogenic differentiation of rBMSCs due to the generation of reactive oxygen species (ROS) while having no influence on their pluripotency. In brief, this study not only implements a cellular labeling method based on CDs that were synthesized by a biomimicking strategy, but also paves a new way to regulate the differentiation of MSCs by designing multifunctional nanomaterials; this will enable the extensive development of facile synthesis methods and new applications of CDs and will also provide some research foundations for MSC-based fields.


Assuntos
Carbono/farmacologia , Glicosaminoglicanos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Pontos Quânticos/química , Ácidos Sulfanílicos/farmacologia , Animais , Carbono/química , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Glicosaminoglicanos/síntese química , Glicosaminoglicanos/química , Estrutura Molecular , Imagem Óptica , Osteogênese/efeitos dos fármacos , Tamanho da Partícula , Ratos , Espécies Reativas de Oxigênio/análise , Ácidos Sulfanílicos/química , Propriedades de Superfície
6.
BMJ Open ; 10(5): e034804, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32385061

RESUMO

INTRODUCTION: Acute exacerbation (AE) is a major cause of disease progression and death in patients with chronic obstructive pulmonary disease (COPD), accounting for majority of medical expenditures. Correct inhalation therapy is effective in preventing AE attacks. However, inappropriate usage of dry powder inhaler, partially due to the unrecovered peak inhalation flow rate (PIFR) after acute exacerbation of COPD (AECOPD), results in increased risk of early treatment failure. Therefore, we designed a multicentre, randomised clinical trial to determine whether PIFR-based optimised inhalation therapy and training on inhaler usage at discharge could effectively reduce early treatment failure events. METHODS AND ANALYSIS: A total of 416 hospitalised patients just recovering from AECOPD will be recruited and equally randomised into the PIFR group and the control group at a 1:1 ratio. The PIFR group will receive additive support before discharge, including choice of PIFR-guided inhaler and education on its usage. PIFR is measured by InCheck DIAL. In comparison, the control group will receive inhalers based on judgement of the respiratory physician. The primary outcome of the study is 30-day treatment failure rate. Other endpoints include PIFR, error rate of inhalation device use, satisfaction with inhalation devices, 30-day mortality, 90-day mortality, symptoms and quality of life of patients, and COPD-related treatment costs. ETHICS AND DISSEMINATION: The trial has been approved by the Ethics Committee of Zhongshan Hospital of Fudan University (B2019-142). Participants will be screened and enrolled from hospitalised patients with AECOPD by clinicians, with no public advertisement for recruitment. After the trial has completed, the results will be reported to the public through conference presentations and peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT04000958.


Assuntos
Doença Crônica , Inaladores de Pó Seco , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Terapia Respiratória , Adulto , Idoso , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Satisfação do Paciente/estatística & dados numéricos , Estudos Prospectivos , Falha de Tratamento
7.
Int J Biometeorol ; 61(11): 1919-1925, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28567499

RESUMO

This panel study investigates how temperature, humidity, and their interaction affect chronic obstructive pulmonary disease (COPD) patients' self-reported symptoms. One hundred and six COPD patients from Shanghai, China, were enrolled, and age, smoking status, St. George Respiratory Questionnaire (SGRQ) score, and lung function index were recorded at baseline. The participants were asked to record their indoor temperature, humidity, and symptoms on diary cards between January 2011 and June 2012. Altogether, 82 patients finished the study. There was a significant interactive effect between temperature and humidity (p < 0.0001) on COPD patients. When the indoor humidity was low, moderate, and high, the indoor temperature ORs were 0.969 (95% CI 0.922 to 1.017), 0.977 (0.962 to 0.999), and 0.920 (95% CI 0.908 to 0.933), respectively. Low temperature was a risk factor for COPD patients, and high humidity enhanced its risk on COPD. The indoor temperature should be kept at least on average at 18.2 °C, while the humidity should be less than 70%. This study demonstrates that temperature and humidity were associated with COPD patients' symptoms, and high humidity would enhance the risk of COPD due to low temperature.


Assuntos
Umidade , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Temperatura , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Saúde Gerados pelo Paciente , Autorrelato , Avaliação de Sintomas
8.
Chin Med J (Engl) ; 126(12): 2248-53, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23786933

RESUMO

BACKGROUND: Recent studies have shown that T helper type-2 (Th2) cells can induce the apoptosis of CD4+CD25+ Treg cells or resist the immunosuppressive effect of Treg cells. We hypothesize that an imbalance of Th2/Treg is present in patients with allergic asthma. METHODS: Twenty-two patients with mild asthma, 17 patients with moderate to severe asthma, and 20 healthy donors were enrolled. All patients were allergic to house dust mites. The proportion of peripheral blood CD4+CD25+ Treg cells and Th2 cells were determined by flow cytometry. The concentration of interleukin (IL)-10, transforming growth factor (TGF)-ß and IL-4 in plasma was determined by enzyme linked immunosorbent assay. In these subjects, peripheral blood mononuclear cells from 17 mild asthmatic patients, 13 moderate to severe asthmatic patients and 14 healthy donors were acquired and expression of forkhead box P3 (Foxp3) and GATA-3 mRNA was detected by reverse-transcriptase polymerase chain reaction. RESULTS: Compared with healthy donors and patients with mild asthma, the percent of CD4+CD25+ Treg cells and plasma IL-10 levels were decreased in patients with moderate to severe asthma. There were no significant differences in Foxp3 mRNA expression among three groups, but a downward trend seen among patients with asthma. However, the percent of Th2 cells, IL-4 levels and expression of GATA-3 mRNA was markedly higher in patients with mild and moderate to severe asthma than in the control group. The ratio of Th2/Treg and their cytokines was increased in allergic asthma, especially for moderate to severe asthma. The ratio of GATA-3/Foxp3 mRNA was also increased in allergic asthma. In patients with moderate to severe asthma, the percentage of peripheral blood Treg cells was negatively correlated to the percentage of Th2 cells and IL-4 levels. CONCLUSIONS: The decline of CD4+CD25+ Treg cells in patients with moderate to severe asthma may play an important role in progress of the disease. Furthermore, the deficiency of CD4+CD25+ Treg cells was associated with the over-expression of Th2 response.


Assuntos
Asma/imunologia , Linfócitos T Reguladores/imunologia , Células Th2/imunologia , Asma/etiologia , Citocinas/sangue , Fatores de Transcrição Forkhead/genética , Fator de Transcrição GATA3/genética , Humanos , RNA Mensageiro/análise
9.
Chin Med J (Engl) ; 124(13): 1951-6, 2011 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-22088452

RESUMO

BACKGROUND: Recent recognition is that Th2 response is insufficient to fully explain the aetiology of asthma. Other CD4(+) T cells subsets might play a role in asthma. We investigated the relative abundance and activities of Th1, Th2, Th17 and CD4(+)CD25(+) Treg cells in patients with allergic asthma. METHODS: Twenty-two patients with mild asthma, 17 patients with moderate to severe asthma and 20 healthy donors were enrolled. All patients were allergic to house dust mites. Plasma total IgE, pulmonary function and Asthma Control Questionnaire were assessed. The proportions of peripheral blood Th1, Th2, Th17 and CD4(+)CD25(+) Treg cells were determined by flow cytometry. The expression of cytokines in plasma and in the culture supernatant of peripheral blood mononuclear cells was determined by enzyme linked, immunosorbent assay. RESULTS: The frequency of blood Th2 cells and IL-4 levels in plasma and culture supernatant of peripheral blood mononuclear cells were increased in all patients with allergic asthma. The frequency of Th17 cells and the plasma and culture supernatant levels of IL-17 were increased, whereas the frequency of CD4(+)CD25(+) Treg cells and plasma IL-10 levels were decreased in patients with moderate to severe asthma. Dermatophagoides pteronyssinus specific IgE levels were positively correlated with the percentage of blood Th2 cells and plasma IL-4 levels. Forced expiratory volume in the first second was negatively correlated with the frequency of Th17 cells and plasma IL-17 levels, and positively correlated with the frequency of Treg cells. However, mean Asthma Control Questionnaire scores were positively correlated with the frequency of Th17 cells and plasma IL-17 levels, and negatively correlated with the frequency of Treg cells. CONCLUSIONS: Imbalances in Th1/Th2 and Th17/Treg were found in patients with allergic asthma. Furthermore, elevated Th17 cell responses, the absence of Tregs and an imbalance in Th17/Treg levels were associated with moderate to severe asthma.


Assuntos
Asma/imunologia , Asma/metabolismo , Interleucina-17/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th2/imunologia , Adulto , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Feminino , Citometria de Fluxo , Humanos , Interleucina-10/sangue , Interleucina-17/metabolismo , Interleucina-4/sangue , Masculino , Linfócitos T Reguladores/metabolismo
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