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1.
Nature ; 590(7847): 594-599, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33627812

RESUMEN

Natural load-bearing materials such as tendons have a high water content of about 70 per cent but are still strong and tough, even when used for over one million cycles per year, owing to the hierarchical assembly of anisotropic structures across multiple length scales1. Synthetic hydrogels have been created using methods such as electro-spinning2, extrusion3, compositing4,5, freeze-casting6,7, self-assembly8 and mechanical stretching9,10 for improved mechanical performance. However, in contrast to tendons, many hydrogels with the same high water content do not show high strength, toughness or fatigue resistance. Here we present a strategy to produce a multi-length-scale hierarchical hydrogel architecture using a freezing-assisted salting-out treatment. The produced poly(vinyl alcohol) hydrogels are highly anisotropic, comprising micrometre-scale honeycomb-like pore walls, which in turn comprise interconnected nanofibril meshes. These hydrogels have a water content of 70-95 per cent and properties that compare favourably to those of other tough hydrogels and even natural tendons; for example, an ultimate stress of 23.5 ± 2.7 megapascals, strain levels of 2,900 ± 450 per cent, toughness of 210 ± 13 megajoules per cubic metre, fracture energy of 170 ± 8 kilojoules per square metre and a fatigue threshold of 10.5 ± 1.3 kilojoules per square metre. The presented strategy is generalizable to other polymers, and could expand the applicability of structural hydrogels to conditions involving more demanding mechanical loading.

2.
Proc Natl Acad Sci U S A ; 120(31): e2301364120, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37487078

RESUMEN

In nearly all cases of underwater adhesion, water molecules typically act as a destroyer. Thus, removing interfacial water from the substrate surfaces is essential for forming super-strong underwater adhesion. However, current methods mainly rely on physical means to dislodge interfacial water, such as absorption, hydrophobic repulsion, or extrusion, which are inefficient in removing obstinate hydrated water at contact interface, resulting in poor adhesion. Herein, we present a unique means of reversing the role of water to assist in realizing a self-strengthening liquid underwater adhesive (SLU-adhesive) that can effectively remove water at contact interface. This is achieved through multiscale physical-chemical coupling methods across millimeter to molecular levels and self-adaptive strengthening of the cohesion during underwater operations. As a result, strong adhesion over 1,600 kPa (compared to ~100 to 1,000 kPa in current state of the art) can be achieved on various materials, including inorganic metal and organic plastic materials, without preloading in different environments such as pure water, a wide range of pH solutions (pH = 3 to 11), and seawater. Intriguingly, SLU-adhesive/photothermal nanoparticles (carbon nanotubes) hybrid materials can significantly reduce the time required for complete curing from 24 h to 40 min using near-infrared laser radiation due to unique thermal-response of the chemical reaction rate. The excellent adhesion property and self-adaptive adhesion procedure allow SLU-adhesive materials to demonstrate great potential for broad applications in underwater sand stabilization, underwater repair, and even adhesion failure detection as a self-reporting adhesive. This concept of "water helper" has potential to advance underwater adhesion and manufacturing strategies.

3.
Small ; : e2403303, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-39031810

RESUMEN

Lubricating hydrogel coatings on inert rubber and plastic surfaces significantly reduce friction and wear, thus enhancing material durability and lifespan. However, achieving optimal hydration lubrication typically requires a porous polymer network, which unfortunately reduces their mechanical strength and limits their applicability where robust durability and wear-resistance are essential. In the research, a hydrogel coating with remarkable wear resistance and surface stability is developed by forming a semi-interpenetrating polymer network with polymer substrate at the interface. By employing a good solvent swelling method, monomers, and photoinitiators are embedded within the substrates' subsurface, followed by in situ polymerization under ultraviolet light, creating a robust semi-interpenetrating and entangled network structure. This approach, offering a thicker energy-dissipating layer, outperforms traditional surface modifications in wear resistance while preserving anti-fatigue, hydrophilicity, oleophobicity, and other properties. Adaptable to various rubber and plastic substrates by using suitable solvents, this method provides an efficient solution for creating durable, lubricating surfaces, broadening the potential applications in multiple industries.

4.
Proc Natl Acad Sci U S A ; 117(21): 11240-11246, 2020 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-32393646

RESUMEN

Ice accumulation causes various problems in our daily life for human society. The daunting challenges in ice prevention and removal call for novel efficient antiicing strategies. Recently, photothermal materials have gained attention for creating icephobic surfaces owing to their merits of energy conservation and environmental friendliness. However, it is always challenging to get an ideal photothermal material which is cheap, easily fabricating, and highly photothermally efficient. Here, we demonstrate a low-cost, high-efficiency superhydrophobic photothermal surface, uniquely based on inexpensive commonly seen candle soot. It consists of three components: candle soot, silica shell, and polydimethylsiloxane (PDMS) brushes. The candle soot provides hierarchical nano/microstructures and photothermal ability, the silica shell strengthens the hierarchical candle soot, and the grafted low-surface-energy PDMS brushes endow the surface with superhydrophobicity. Upon illumination under 1 sun, the surface temperature can increase by 53 °C, so that no ice can form at an environmental temperature as low as -50 °C and it can also rapidly melt the accumulated frost and ice in 300 s. The superhydrophobicity enables the melted water to slide away immediately, leaving a clean and dry surface. The surface can also self-clean, which further enhances its effectiveness by removing dust and other contaminants which absorb and scatter sunlight. In addition, after oxygen plasma treatment, the surface can restore superhydrophobicity with sunlight illumination. The presented icephobic surface shows great potential and broad impacts owing to its inexpensive component materials, simplicity, ecofriendliness, and high energy efficiency.

5.
BMC Biol ; 20(1): 274, 2022 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-36482454

RESUMEN

BACKGROUND: Root development and function have central roles in plant adaptation to the environment. The modification of root traits has additionally been a major driver of crop performance since the green revolution; however, the molecular underpinnings and the regulatory programmes defining root development and response to environmental stress remain largely unknown. Single-cell reconstruction of gene regulatory programmes provides an important tool to understand the cellular phenotypic variation in complex tissues and their response to endogenous and environmental stimuli. While single-cell transcriptomes of several plant organs have been elucidated, the underlying chromatin landscapes associated with cell type-specific gene expression remain largely unexplored. RESULTS: To comprehensively delineate chromatin accessibility during root development of an important crop, we applied single-cell ATAC-seq (scATAC-seq) to 46,758 cells from rice root tips under normal and heat stress conditions. Our data revealed cell type-specific accessibility variance across most of the major cell types and allowed us to identify sets of transcription factors which associate with accessible chromatin regions (ACRs). Using root hair differentiation as a model, we demonstrate that chromatin and gene expression dynamics during cell type differentiation correlate in pseudotime analyses. In addition to developmental trajectories, we describe chromatin responses to heat and identify cell type-specific accessibility changes to this key environmental stimulus. CONCLUSIONS: We report chromatin landscapes during rice root development at single-cell resolution. Our work provides a framework for the integrative analysis of regulatory dynamics in this important crop organ at single-cell resolution.


Asunto(s)
Meristema , Oryza , Cromatina/genética , Oryza/genética
6.
J Environ Manage ; 328: 116944, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36525734

RESUMEN

Pollution from polycyclic aromatic hydrocarbons (PAHs) spreads and changes worldwide. The pollution evolution in the regional water environment evolves in response to multiple factors, requiring considerable attention. PAH heterogeneity in the sediment core from Chaihe Reservoir was investigated to indicate dynamic changes in PAH pollution levels and sources and propose recommendations for controlling PAHs. Dynamic PAH patterns showed that the overall decline in PAH pollution was in association with local anthropogenic activities, temperature, and precipitation over the period 1863-2018. Nevertheless, coal, oil, and natural gas consumptions still played significant roles in transferring PAHs to the reservoir. Meanwhile, there were dominant local origins, including grass, wood, and coal combustion. The results highlight that the joint action of natural and anthropogenic interventions mitigated PAH pollution in the reservoir. Promoting improved fuels, new energy vehicles, and cleaner energy may further lower PAH pollution.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos , Monitoreo del Ambiente/métodos , Carbón Mineral/análisis , China
7.
J Pharmacol Exp Ther ; 382(3): 287-298, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35688476

RESUMEN

Urocortin-1 (UCN1) is a member of the corticotropin releasing hormone (CRH) family of peptides that acts through CRH-receptor 1 (CRHR1) and CRH-receptor 2 (CRHR2). UCN1 can induce the adrenocorticotropin hormone and downstream glucocorticoids through CRHR1 and promote beneficial metabolic effects through CRHR2. UCN1 has a short half-life and has been shown to improve experimental autoimmune disease. A pegylated UCN1 peptide (PEG-hUCN1) was generated to extend half-life and was tested in multiple experimental autoimmune disease models and in healthy mice to determine effects on corticosterone induction, autoimmune disease, and glucocorticoid induced adverse effects. Cardiovascular effects were also assessed by telemetry. PEG-hUCN1 demonstrated a dose dependent 4-6-fold elevation of serum corticosterone and significantly improved autoimmune disease comparable to prednisolone in several experimental models. In healthy mice, PEG-hUCN1 showed less adverse effects compared with corticosterone treatment. PEG-hUCN1 peptide induced an initial 30% reduction in blood pressure that was followed by a gradual and sustained 30% increase in blood pressure at the highest dose. Additionally, an adeno-associated viral 8 (AAV8) UCN1 was used to assess adverse effects of chronic elevation of UCN1 in wild type and CRHR2 knockout mice. Chronic UCN1 expression by an AAV8 approach in wild type and CRHR2 knockout mice demonstrated an important role of CRHR2 in countering the adverse metabolic effects of elevated corticosterone from UCN1. Our findings demonstrate that PEG-hUCN1 shows profound effects in treating autoimmune disease with an improved safety profile relative to corticosterone and that CRHR2 activity is important in metabolic regulation. SIGNIFICANCE STATEMENT: This study reports the generation and characterization of a pegylated UCN1 peptide and the role of CRHR2 in UCN1-induced metabolic effects. The potency/selectivity, pharmacokinetic properties, pharmacodynamic effects, and efficacy in four autoimmune models and safety profiles are presented. This pegylated UCN1 shows potential for treating autoimmune diseases with reduced adverse effects compared to corticosterone treatment. Continuous exposure to UCN1 through an AAV8 approach demonstrates some glucocorticoid mediated adverse metabolic effects that are exacerbated in the absence of the CRHR2 receptor.


Asunto(s)
Enfermedades Autoinmunes , Urocortinas , Animales , Enfermedades Autoinmunes/tratamiento farmacológico , Corticosterona , Hormona Liberadora de Corticotropina/metabolismo , Hormona Liberadora de Corticotropina/farmacología , Glucocorticoides , Ratones , Ratones Noqueados , Modelos Teóricos , Polietilenglicoles/farmacología , Receptores de Hormona Liberadora de Corticotropina/metabolismo , Urocortinas/metabolismo , Urocortinas/farmacología
8.
Anticancer Drugs ; 33(1): e207-e217, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34407052

RESUMEN

This study aimed to investigate the role and potential mechanisms of LINC00987 in acute myeloid leukemia (AML) progression. The expression of LINC00987 in bone marrow specimens of AML patients and cell lines was measured by quantitative reverse transcription PCR (RT-qPCR). Small interfering RNA targeting LINC00987 (si-LINC00987) was transfected into AML cell lines HL-60 and KG-1, and the proliferation, invasion and apoptosis were detected with Cell Counting Kit-8 (CCK-8), Transwell and flow cytometry, respectively. Moreover, the binding between LINC00987 and insulin like growth factor 2 mRNA binding protein 2 (IGF2BP2) was validated with an RNA pull-down assay. Co-immunoprecipitation assay was used to verify the binding between IGF2BP2 and proliferation-associated 2G4 (PA2G4). Then rescue experiments were performed to explore the effects of LINC00987/IGF2BP2/PA2G4 axis on HL-60 and KG-1 cell functions. Additionally, HL-60 cells transfected with si-LINC00987 were injected into mice, followed by the evaluation of xenograft tumor growth. LINC00987 was upregulated in AML patient specimens and cell lines. LINC00987 knockdown inhibited proliferation and invasion and promoted apoptosis in AML cells. LINC00987 could bind with IGF2BP2 and promote its expression, and IGF2BP2 overexpression reversed the effects of LINC00987 knockdown on the proliferation, invasion and apoptosis in AML cells. Besides, IGF2BP2 could bind with PA2G4. IGF2BP2 knockdown inhibited proliferation and invasion, and promoted apoptosis in AML cells, whereas PA2G4 overexpression reversed these effects. Additionally, the LINC00987 knockdown inhibited the xenograft tumor growth of AML in vivo. Knockdown of LINC00987 inhibits AML cell proliferation and invasion, and promotes apoptosis in vitro and reduces tumor growth in vivo by suppressing IGF2BP2-mediated PA2G4 expression.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Leucemia Mieloide Aguda/patología , ARN Largo no Codificante/genética , Proteínas de Unión al ARN/biosíntesis , Animales , Apoptosis/fisiología , Línea Celular Tumoral , Humanos , Leucemia Mieloide Aguda/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , ARN Interferente Pequeño/biosíntesis , Regulación hacia Arriba , Ensayos Antitumor por Modelo de Xenoinjerto
9.
J Psychosoc Nurs Ment Health Serv ; 60(10): 21-27, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35417280

RESUMEN

Using a cluster sampling method, 248 nurses from frontline departments of three large general hospitals in Sichuan Province, China, were selected as participants in the current study. Risk perception and coping methods during the coronavirus disease 2019 (COVID-19) pandemic, negative emotions and psychological workload, and awareness of social support among nurses were studied. Negative emotions among nurses increased significantly, with fear being the most common (73.4%, n = 182). Psychological workload of nurses in close contact with patients with COVID-19 was higher than that of nurses in other positions (p < 0.05). Family was the major source of social support. Social support was negatively associated with depression (-0.206, p < 0.05), obsessive-compulsiveness/anxiety (-0.185, p < 0.05), and hypochondriasis (-0.234, p < 0.05). Psychological workload of nurses was positively correlated with depression (0.251, p < 0.05), neurasthenia (0.242, p < 0.05), and obsessive-compulsiveness/anxiety (0.231, p < 0.05). Nursing staff in frontline departments encountered psychological workload burdens to varying degrees during the COVID-19 pandemic. Thus, it is important to implement and strengthen psychological counseling for nurses in close contact positions, and to seek family and social support for nurses. [Journal of Psychosocial Nursing and Mental Health Services, 60(10), 21-27.].


Asunto(s)
COVID-19 , Enfermeras y Enfermeros , Estrés Laboral , Ansiedad/epidemiología , Ansiedad/psicología , China/epidemiología , Humanos , Estrés Laboral/epidemiología , Pandemias , Apoyo Social , Estrés Psicológico
10.
Acc Chem Res ; 52(3): 704-713, 2019 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-30835432

RESUMEN

Various methods have been developed in surface chemistry to control interface properties of a solid material. A selection rule among surface chemistries is compatibility between a surface functionalization tool and a target material. For example, alkanethiol deposition on noble metal surfaces, widely known as the formation of a self-assembled monolayer (SAM), cannot be performed on oxide material surfaces. One must choose organosilane molecules to functionalize oxide surfaces. Thus, the surface chemistry strictly depends on the properties of the surface. Polydopamine coating is now generally accepted as the first toolbox for functionalization of virtually any material surface. Layer-by-layer (LbL) assembly is a widely used method to modify properties of versatile surfaces, including organic materials, metal oxides, and noble metals, along with polydopamine coating. On flat solid substrates, the two chemistries of polydopamine coating and LbL assembly provide similar levels of surface modifications. However, there are additional distinct features in polydopamine. First, polydopamine coating is effective for two- or three-dimensional porous materials such as metal-organic frameworks (MOFs), synthetic polyolefin membranes, and others because small-sized dopamine (MW = 153.18 u) and its oxidized oligomers are readily attached onto narrow-spaced surfaces without exhibiting steric hindrance. In contrast, polymers used in LbL assembly are slow in diffusion because of steric hindrance due to their high molecular weight. Second, it is applicable to structurally nonflat surfaces showing special wettability such as superhydrophobicity or superoleophobicity. Third, a nonconducting, insulating polydopamine layer can be converted to be a conducting layer by pyrolysis. The product after pyrolysis is a N-doped graphene-like material that is useful for graphene or carbon nanotube-containing composites. Fourth, it is a suitable method for engineering the surface properties of various composite materials. The surface properties of participating components in composite materials can be unified by polydopamine coating with a simple one-step process. Fifth, a polydopamine layer exhibits intrinsic chemical reactivity by the presence of catecholquinone moieties and catechol radical species on surfaces. Nucleophiles such as amine and thiolate spontaneously react with the functionalized layer. Applications of polydopamine coating are exponentially growing and include cell culture/patterning, microfluidics, antimicrobial surfaces, tissue engineering, drug delivery systems, photothermal therapy, immobilization of photocatalysts, Li-ion battery membranes, Li-sulfur battery cathode materials, oil/water separation, water detoxification, organocatalysts, membrane separation technologies, carbonization, and others. In this Account, we describe various polydopamine coating methods and then introduce a number of chemical derivatives of dopamine that will open further development of material-independent surface chemistry.

11.
J Nutr ; 150(5): 1313-1323, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32027752

RESUMEN

BACKGROUND: Probiotic Lactobacillius rhamnosus GG (LGG) shows beneficial immunomodulation on cultured cell lines in vitro and in mouse models. OBJECTIVE: The aim was to investigate the effects of LGG on intestinal injury and the underlying mechanisms by elucidating inflammatory signaling pathways and metabolomic response to LPS stimulation in the piglet intestine. METHODS: Piglets (Duroc × Landrace × Large White, including males and female; 8.6 ± 1.1 kg) aged 28 d were assigned to 3 groups (n = 6/group): oral inoculation with PBS for 2 wk before intraperitoneal injection of physiological saline [control (CON)] or LPS (25 µg/kg body weight; LPS) or oral inoculation with LGG for 2 wk before intraperitoneal injection of LPS (LGG+LPS). Piglets were killed 4 h after LPS injection. Systemic inflammation, intestinal integrity, inflammation signals, and metabolomic characteristics in the intestine were determined. RESULTS: Compared with CON, LPS stimulation significantly decreased ileal zonula occludens 1 (ZO-1; 44%), claudin-3 (44%), and occludin (41%) expression; increased serum diamineoxidase (73%), D-xylose (19%), TNF-α (43%), and IL-6 (55%) concentrations; induced p38 mitogen-activated protein kinase (p38 MAPK; 85%), extracellular signal-regulated kinase (ERK; 96%), and NF-κB p65 phosphorylation (37%) (P < 0.05). Compared with LPS stimulation alone, LGG pretreatment significantly enhanced the intestinal barrier by upregulating expressions of tight junction proteins (ZO-1, 73%; claudin-3, 55%; occludin, 67%), thereby decreasing serum diamineoxidase (26%) and D-xylose (28%) concentrations, and also reduced serum TNF-α expression (16%) and ileal p38 MAPK (79%), ERK (43%) and NF-κB p65 (37%) phosphorylation levels (P < 0.05). Metabolomic analysis showed clear separation between each group. The concentrations of caprylic acid [fold-change (FC) = 2.39], 1-mono-olein (FC = 2.68), erythritol (FC = 4.62), and ethanolamine (FC = 4.47) significantly increased in the intestine of LGG + LPS piglets compared with the LPS group (P < 0.05). CONCLUSIONS: These data suggest that LGG alleviates gut inflammation, improves intestinal barrier function, and modulates the metabolite profile of piglets challenged with LPS. This trial was registered at the Zhejiang University (http://www.lac.zju.edu.cn) as ZJU20170529.


Asunto(s)
Gastroenteritis/prevención & control , Enfermedades Gastrointestinales/prevención & control , Lacticaseibacillus rhamnosus/fisiología , Lipopolisacáridos/farmacología , Metaboloma/fisiología , Sus scrofa , Animales , Femenino , Gastroenteritis/inducido químicamente , Enfermedades Gastrointestinales/inducido químicamente , Sistema de Señalización de MAP Quinasas/fisiología , Masculino , Probióticos/administración & dosificación , Transducción de Señal/fisiología , Proteínas de Uniones Estrechas/genética , Factor de Transcripción ReIA/metabolismo , Regulación hacia Arriba/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
12.
Water Sci Technol ; 80(4): 784-793, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31661457

RESUMEN

Coconut shell biochar (CSB) was selected as raw material to obtain two kinds of modified biochars by pickling and iron modification. The pickling coconut shell biochar (PCSB) and pickling-iron modified coconut shell biochar (PICSB) were used as adsorbents to remove NO3-N in alkaline rare earth industry effluent. The results showed that pickling smoothed the surface of CSB, and α-FeOOH was formed on the surface of PCSB because of FeCl3 solution modification. Suitable adsorbent dosages of PCSB and PICSB were both 2.0 g/L. The NO3-N adsorption process by PCSB and PICSB both reached equilibrium at 30 min. The quasi-first-order kinetic model shows good fit to the NO3-N adsorption by PCSB. Whereas, the quasi-second-order kinetic model is more suitable for PICSB adsorbing NO3-N. The adsorption mechanisms of PICSB for NO3-N removal were ligand exchange and electrostatic attraction, and that of PCSB for NO3-N removal was electrostatic attraction. The NO3-N adsorption amounts of PCSB and PICSB decreased with increasing adsorption temperature and pH. The maximum NO3-N adsorption amounts of PCSB and PICSB were 15.14 mg/L and 10.75 mg/L respectively with adsorbent dosage of 2.0 g/L, adsorption time of 30 min, adsorption temperature of 25 ± 1 °C, and initial solution pH of 2.01.


Asunto(s)
Cocos , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico
13.
Water Sci Technol ; 80(10): 2003-2012, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32144232

RESUMEN

To remove NO3-N from water, coconut shell biochar (CSB) was modified by a solution of FeCl3, a solution of AlCl3 and a mixture solution of FeCl3 and AlCl3 respectively. The obtained modified biochar with the best effect of NO3-N adsorption was screened out to explore the adsorption behavior and mechanism of NO3-N removal by batch experiments and kinetics and thermodynamics and correlated characterization. The results indicated that the mixture solution of FeCl3- and AlCl3- modified CSB (Fe-Al/CSB) showed the best adsorption performance for NO3-N removal. Iron and aluminum elements existed on the surface of Fe-Al/CSB in the form of FeOOH, Fe2O3, Fe2+, and Al2O3 respectively. The adsorption process could reach equilibrium in 20 min. An acidic condition was favorable for NO3-N adsorption. The presence of coexisting anions was not conducive for NO3-N adsorption. The quasi-second-order model and Freundlich model could be well fitted in the adsorption process. The maximum adsorption capacity of Fe-Al/CSB fitted by the Langmuir model could reach 34.20 mg/g. The adsorption of NO3-N by Fe-Al/CSB was an endothermic and spontaneous process. Ligand exchange and chemical redox reaction were the NO3-N adsorption mechanisms which led to NO3-N adsorption by Fe-Al/CSB.


Asunto(s)
Contaminantes Químicos del Agua , Agua , Adsorción , Carbón Orgánico , Cinética , Termodinámica
14.
Muscle Nerve ; 54(6): 1120-1132, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27074419

RESUMEN

INTRODUCTION: There is evidence that supports a role for Vitamin D (Vit. D) in muscle. The exact mechanism by which Vit. D deficiency impairs muscle strength and function is not clear. METHODS: Three-week-old mice were fed diets with varied combinations of Vit. D and Ca2+ deficiency. Behavioral testing, genomic and protein analysis, and muscle histology were performed with a focus on neuromuscular junction (NMJ) -related genes. RESULTS: Vit. D and Ca2+ deficient mice performed more poorly on given behavioral tasks than animals with Vit. D deficiency alone. Genomic and protein analysis of the soleus and tibialis anterior muscles revealed changes in several Vit. D metabolic, NMJ-related, and protein chaperoning and refolding genes. CONCLUSIONS: These data suggest that detrimental effects of a Vit. D deficient or a Vit. D and Ca2+ deficient diet may be a result of differential alterations in the structure and function of the NMJ and a lack of a sustained stress response in muscles. Muscle Nerve 54: 1120-1132, 2016.


Asunto(s)
Deficiencia de Ácido Ascórbico/patología , Dieta/efectos adversos , Regulación de la Expresión Génica/fisiología , Miembro Posterior/patología , Fibras Musculares Esqueléticas/fisiología , Unión Neuromuscular/fisiopatología , Factores de Edad , Animales , Deficiencia de Ácido Ascórbico/sangre , Deficiencia de Ácido Ascórbico/etiología , Deficiencia de Ácido Ascórbico/metabolismo , Calcio/metabolismo , Modelos Animales de Enfermedad , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Locomoción , Masculino , Ratones , Ratones Endogámicos C57BL , Fuerza Muscular , Hormona Paratiroidea/sangre , Fósforo/sangre , Equilibrio Postural , Desempeño Psicomotor , Vitamina D/metabolismo
15.
BMC Plant Biol ; 15: 164, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-26122404

RESUMEN

BACKGROUND: Calcium-dependent protein kinases (CDPKs) play vital roles in plant growth and development, biotic and abiotic stress responses, and hormone signaling. Little is known about the CDPK gene family in grapevine. RESULTS: In this study, we performed a genome-wide analysis of the 12X grape genome (Vitis vinifera) and identified nineteen CDPK genes. Comparison of the structures of grape CDPK genes allowed us to examine their functional conservation and differentiation. Segmentally duplicated grape CDPK genes showed high structural conservation and contributed to gene family expansion. Additional comparisons between grape and Arabidopsis thaliana demonstrated that several grape CDPK genes occured in the corresponding syntenic blocks of Arabidopsis, suggesting that these genes arose before the divergence of grapevine and Arabidopsis. Phylogenetic analysis divided the grape CDPK genes into four groups. Furthermore, we examined the expression of the corresponding nineteen homologous CDPK genes in the Chinese wild grape (Vitis pseudoreticulata) under various conditions, including biotic stress, abiotic stress, and hormone treatments. The expression profiles derived from reverse transcription and quantitative PCR suggested that a large number of VpCDPKs responded to various stimuli on the transcriptional level, indicating their versatile roles in the responses to biotic and abiotic stresses. Moreover, we examined the subcellular localization of VpCDPKs by transiently expressing six VpCDPK-GFP fusion proteins in Arabidopsis mesophyll protoplasts; this revealed high variability consistent with potential functional differences. CONCLUSIONS: Taken as a whole, our data provide significant insights into the evolution and function of grape CDPKs and a framework for future investigation of grape CDPK genes.


Asunto(s)
Proteínas de Plantas/genética , Vitis/genética , Secuencia de Aminoácidos , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/metabolismo , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , Alineación de Secuencia , Vitis/metabolismo
16.
Nurs Open ; 11(2): e2107, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38391098

RESUMEN

BACKGROUND: Changes to the wound dressing frequently cause pain. Some adverse side effects of pharmacologic pain management may cause problems or even impede wound healing. There is no systematic study of non-pharmacologic therapies for pain during wound dressing changes, despite the gradual promotion of non-pharmacologic pain reduction methods. OBJECTIVES: To give clinical wound pain management a new direction, locating and assessing non-pharmacological interventions regarding pain brought on by wound dressing changes are necessary. METHOD: The researchers conducted a comprehensive literature review on non-pharmacological interventions for pain during wound dressing changes across five databases: PubMed, Web of Science, Medline, Embase, and the Cochrane Library spanning the period from January 2010 to September 2022. The evaluation of literature and data extraction was carried out independently by two researchers, and in cases of disagreement, a third researcher participated in the deliberation. To assess the risk of bias in the literature, the researchers utilised the Cochrane Handbook for Reviews of Interventions, version 5.1.0. RESULTS: In total, 951 people were involved in 11 investigations covering seven non-pharmacological therapies. For pain triggered by dressing changes, virtual reality (VR) distraction, auditory and visual distractions, foot reflexology, religious and spiritual care, and guided imaging demonstrated partially positive effects, with hypnosis therapy and jaw relaxation perhaps having a weak effect. CONCLUSION: The key to managing wounds is pain management. According to our review, there is some indication that non-pharmacologic interventions can help patients feel less discomfort when having their wound dressings changed. However, the evidence supporting this view is weak. It needs to be corroborated by future research studies with multicentre and large samples. To promote and use various non-pharmacologic interventions in the future, it is also necessary to build standardised and homogenised paths for their implementation.


Asunto(s)
Vendajes , Dolor , Heridas y Lesiones , Humanos , Vendajes/efectos adversos , Dolor/etiología
17.
Biochem Biophys Res Commun ; 441(4): 958-63, 2013 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-24220341

RESUMEN

MicroRNAs (miRNAs) are fundamental regulators of cell proliferation, differentiation, and apoptosis, and are implicated in tumorigenesis of many cancers. MiR-34a is best known as a tumor suppressor through repression of growth factors and oncogenes. Growth arrest specific1 (GAS1) protein is a tumor suppressor that inhibits cancer cell proliferation and induces apoptosis through inhibition of RET receptor tyrosine kinase. Both miR-34a and GAS1 are frequently down-regulated in various tumors. However, it has been reported that while GAS1 is down-regulated in papillary thyroid carcinoma (PTC), miR-34a is up-regulated in this specific type of cancer, although their potential roles in PTC tumorigenesis have not been examined to date. A computational search revealed that miR-34a putatively binds to the 3'-UTR of GAS1 gene. In the present study, we confirmed previous findings that miR-34a is up-regulated and GAS1 down-regulated in PTC tissues. Further studies indicated that GAS1 is directly targeted by miR-34a. Overexpression of miR-34a promoted PTC cell proliferation and colony formation and inhibited apoptosis, whereas knockdown of miR-34a showed the opposite effects. Silencing of GAS1 had similar growth-promoting effects as overexpression of miR-34a. Furthermore, miR-34a overexpression led to activation of PI3K/Akt/Bad signaling pathway in PTC cells, and depletion of Akt reversed the pro-growth, anti-apoptotic effects of miR-34a. Taken together, our results demonstrate that miR-34a regulates GAS1 expression to promote proliferation and suppress apoptosis in PTC cells via PI3K/Akt/Bad pathway. MiR-34a functions as an oncogene in PTC.


Asunto(s)
Apoptosis , Carcinoma/genética , Carcinoma/patología , Proteínas de Ciclo Celular/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/fisiología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Carcinoma Papilar , Línea Celular Tumoral , Proliferación Celular , Regulación hacia Abajo , Proteínas Ligadas a GPI/genética , Silenciador del Gen , Humanos , MicroARNs/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Cáncer Papilar Tiroideo , Regulación hacia Arriba , Proteína Letal Asociada a bcl/metabolismo
18.
Front Microbiol ; 14: 1122966, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36891398

RESUMEN

In this study, micron-sized monodisperse SiO2 microspheres were used as sacrificial templates, and chitosan/polylactic acid (CTS/PLA) bio-microcapsules were produced using the layer-by-layer (LBL) assembly method. Microcapsules isolate bacteria from their surroundings, forming a separate microenvironment and greatly improving microorganisms' ability to adapt to adverse environmental conditions. Morphology observation indicated that the pie-shaped bio-microcapsules with a certain thickness could be successfully prepared through LBL assembly method. Surface analysis showed that the LBL bio-microcapsules (LBMs) had large fractions of mesoporous. The biodegradation experiments of toluene and the determination of toluene degrading enzyme activity were also carried out under external adverse environmental conditions (i.e., unsuitable initial concentrations of toluene, pH, temperature, and salinity). The results showed that the removal rate of toluene by LBMs can basically reach more than 90% in 2 days under adverse environmental conditions, which is significantly higher than that of free bacteria. In particular, the removal rate of toluene by LBMs can reach four times that of free bacteria at pH 3, which indicates that LBMs maintain a high level of operational stability for toluene degradation. Flow cytometry analysis showed that LBL microcapsules could effectively reduce the death rate of the bacteria. The results of the enzyme activity assay showed that the enzyme activity was significantly stronger in the LBMs system than in the free bacteria system under the same unfavorable external environmental conditions. In conclusion, the LBMs were more adaptable to the uncertain external environment, which provided a feasible bioremediation strategy for the treatment of organic contaminants in actual groundwater.

19.
Gland Surg ; 12(2): 197-207, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36915815

RESUMEN

Background: Human epidermal growth factor receptor 2 (HER2) is a landmark protein in determining the targeted treatment of breast cancer (BC). However, the latest research shows that different intensity of HER2 protein expression levels in BC leads to different clinical characteristics, treatment, and prognosis, especially in HER2 low expression patients. Therefore, this study intends to analyze and compare the clinicopathologic features and prognosis of BC patients with low and zero HER2 expression from The Cancer Genome Atlas (TCGA) database and the data collected by our center. Methods: First, the BC dataset was downloaded from TCGA database, including 345 eligible and with complete clinical information BC patients, to compare the difference between HER2 low expression groups and HER2 zero expression groups and their correlation with estrogen receptor (ER) and progesterone receptor (PR) expression. Then, the clinicopathological data and follow-up of 405 patients with HER2 low expression and HER2 zero expression diagnosed with BC admitted to the Affiliated Hospital of Youjiang Medical University for Nationalities (YJMU) from January 2017 to December 2021 were collected to verify the consistency of the results of the two data sets. Results: Both the clinical samples and the TCGA data showed that the ER and PR rates were higher in the HER2 low expression group compared with the HER2 zero expression group. There were no significant differences in tumor size, lymph node metastasis, distant metastasis, and disease-free survival (DFS). In addition, the data analysis of 405 clinical samples also showed that the HER2 low expression group had a lower 3-year recurrence or metastasis rate compared with the HER2 zero expression group. Conclusions: Compared with HER2 zero expression, HER2 low patients express more ER and PR, and have less short-term recurrence and metastasis, but there is no obvious difference in DFS between the two groups.

20.
Int J Med Robot ; : e2584, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37792998

RESUMEN

OBJECTIVE: To evaluate the feasibility and application value of mixed reality technology (MR) in Primary retroperitoneal tumour (PRT) surgery. METHODS: From 276 patients who underwent PRT resection at the First Affiliated Hospital of Xi'an Jiaotong University, we screened 46 patients who underwent MR-assisted retroperitoneal tumour resection and 46 patients who underwent tumour resection without MR assistance. The intraoperative and postoperative recovery of the patients in both groups were compared, and the reliability and validity of the application of MR were further examined using the Likert scale. RESULTS: There was a significant difference in the mean intraoperative bleeding volume between the two groups, but it was reduced in the MR group. The results of the Likert scale showed higher scores in the MR group than non-MR group. CONCLUSIONS: MR can be used to assist PRT resection and has great potential to improve the rate of complete retroperitoneal tumour resection.

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