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排序方式: 共有348条查询结果,搜索用时 15 毫秒
341.
Sauliha R. Alli Ilona Gorbovskaya Jonathan C. W. Liu Nathan J. Kolla Lisa Brown Daniel J. Müller 《International journal of molecular sciences》2022,23(9)
An emerging body of literature demonstrates differences in the gut microbiome (GMB) of patients with major depressive disorder (MDD) compared to healthy controls (HC), as well as the potential benefits of prebiotic, probiotic, and synbiotic treatment. We conducted a systematic review of 24 observational studies (n = 2817), and 19 interventional trials (n = 1119). We assessed alpha diversity, beta diversity, and taxa abundance changes in patients with MDD relative to HC, as well as the effect of prebiotics, probiotics, and synbiotics on depressive symptoms in individuals with clinical or subclinical depression. We observed no significant differences in alpha diversity but a significant difference in beta diversity between patients with MDD and HC. There were fluctuations in the abundance of specific taxa in patients with MDD relative to HC. Probiotic and synbiotic, but not prebiotic, treatment showed a modest benefit in reducing depressive symptoms in patients with MDD over four to nine weeks. The GMB profiles of patients with MDD differ significantly from HC, but further studies are needed to elucidate the benefits of prebiotic, probiotic and synbiotic treatments relative to antidepressants and over longer follow-up before these therapies are implemented into clinical practice. 相似文献
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343.
Bhagat Rabi S.; McQuaid Sara J.; Lindholm Hal; Segovis James 《Canadian Metallurgical Quarterly》1985,70(1):202
Measured the construct of total life stress using an 83-item checklist with 282 full-time, white collar administrative, health care, and clerical personnel working for 5 organizations (mean ages 37.45, 37.74, 36.15, 35.04, and 43.71 yrs). Checklist items concerned stressful job and personal life events. Regression analyses predicted 6 different organizational outcomes using the constructs of job stress, personal life stress, and total life stress, respectively. Greater understanding of the effects of stress was achieved when researchers recognized the separate effects of positive vs negative stress and considered the employee in a holistic perspective by taking into account the combined effects of job stress and personal life stress on employee well-being. Results provide evidence for the convergent validity of the total life stress construct as measured separately by its 2 components, total positive and total negative life stress. (52 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
344.
The diversity of exosomes and their role in the microenvironment make them an important point of interest in the development of cancer. In our study, we evaluated the effect of exosomes derived from ovarian cancer cells on gene expression in fibroblasts, including genes involved in metastasis. We also attempted to evaluate the indirect effect of cisplatin and/or α-mangostin on metastasis. In this aspect, we verified the changes induced by the drugs we tested on vesicular transfer associated with the release of exosomes by cells. We isolated exosomes from ovarian cancer cells treated and untreated with drugs, and then normal human fibroblasts were treated with the isolated exosomes. Changes in the expression of genes involved in the metastasis process were then examined. In our study, we observed altered expression of genes involved in various steps of the metastasis process (including genes related to cell adhesion, genes related to the interaction with the extracellular matrix, the cell cycle, cell growth and proliferation, and apoptosis). We have shown that α-mangostin and/or cisplatin, as chemotherapeutic agents, not only directly affect tumor cells but may also indirectly (via exosomes) contribute to delaying metastasis development. 相似文献
345.
Ilona Jaszczuk Izabela Winkler Dorota Koczkodaj Maciej Skrzypczak Agata Filip 《International journal of molecular sciences》2022,23(22)
Pre-eclampsia is a placenta-related complication occurring in 2–10% of all pregnancies. miRNAs are a group of non-coding RNAs regulating gene expression. There is evidence that C19MC miRNAs are involved in the development of the placenta. Deregulation of chromosome 19 microRNA cluster (C19MC) miRNAs expression leads to impaired cell differentiation, abnormal trophoblast invasion and pathological angiogenesis, which can lead to the development of pre-eclampsia. Information was obtained through a review of articles available in PubMed Medline. Articles on the role of the C19MC miRNA in the development of pre-eclampsia published in 2009–2022 were analyzed. This review article summarizes the current data on the role of the C19MC miRNA in the development of pre-eclampsia. They indicate a significant increase in the expression of most C19MC miRNAs in placental tissue and a high level of circulating fractions in serum and plasma, both in the first and/or third trimester in women with PE. Only for miR-525-5p, low levels of plasma expression were noted in the first trimester, and in the placenta in the third trimester. The search for molecular factors indicating the development of pre-eclampsia before the onset of clinical symptoms seems to be a promising diagnostic route. Identifying women at risk of developing pre-eclampsia at the pre-symptomatic stage would avoid serious complications in both mothers and fetuses. We believe that miRNAs belonging to cluster C19MC could be promising biomarkers of pre-eclampsia development. 相似文献
346.
Csenge Vámos Ilona Rácz Tamás Bárány Alfréd Menyhárd Botond Béla Marosfői 《Polymer Engineering and Science》2023,63(4):1289-1302
We have introduced a novel solvent-based method to roughen polymer surfaces and characterized treated polypropylene (PP). The method consists of three main steps: solvent treatment, drying, and peeling. We investigated the effects of process parameters such as time of immersion in the solvent, solvent temperature, and drying temperature on the surface morphology created. The structure formed on the surface is mainly influenced by solvent temperature and drying temperature. We also characterized the wetting behavior of the surfaces. The patterned surfaces exhibit superhydrophobic characteristics with a high water contact angle (CA) (>155 °) and low water contact hysteresis (<5°). Adding an effective nucleating agent to PP makes it possible to generate outstanding CAs (>160°) and tailor spherulite sizes. The method is simple and scalable, therefore this superhydrophobic material is easy to mass-produce. 相似文献
347.
Ilona Wagner Simon Spiegel Julian Brückel Matthias Schwotzer Alexander Welle Martina H. Stenzel Stefan Bräse Salma Begum Manuel Tsotsalas 《大分子材料与工程》2023,308(9):2300048
Surface engineering of metal–organic framework nanoparticles (MOF NPs), and enabling their post-synthetic modulation that facilitates the formation of bio-interfaces has tremendous potential for diverse applications including therapeutics, imaging, biosensing, and drug-delivery systems. Despite the progress in MOF NPs synthesis, colloidal stability and homogeneous dispersity—a desirable property for biotechnological applications, stands as a critical obstacle and remains a challenging task. In this report, dynamic surfaces modification of MOF NPs with polyethylene glycol (PEG) polymer is described using grafting-from PEGylation by employing nitroxide-mediated polymerization (NMP) and inserting arginylglycylaspartic acid (RGD) peptides on the surface via a nitroxide exchange reaction (NER). The dynamic modification strategy enables tailoring PEG-grafted MOF NPs of the type UiO-66-NH2 with improved colloidal stability, and high dispersity, while the morphology and lattice crystallinity are strictly preserved. The interaction of PEG-grafted MOF NPs with human serum albumin (HSA) protein under physiological conditions is studied. The PEG-grafted colloidal MOF NPs adsorb less HSA protein than the uncoated ones. Therefore, the described approach increases the scope of bio-relevant applications of colloidal MOF NPs by reducing nonspecific interactions using NMP based PEGylation, while preserving the possibility to introduce targeting moieties via NER for specific interactions. 相似文献
348.