Search results for "actin"
showing 10 items of 1375 documents
A core cochlear phenotype in USH1 mouse mutants implicates fibrous links of the hair bundle in its cohesion, orientation and differential growth
2008
The planar polarity and staircase-like pattern of the hair bundle are essential to the mechanoelectrical transduction function of inner ear sensory cells. Mutations in genes encoding myosin VIIa, harmonin, cadherin 23,protocadherin 15 or sans cause Usher syndrome type I (USH1, characterized by congenital deafness, vestibular dysfunction and retinitis pigmentosa leading to blindness) in humans and hair bundle disorganization in mice. Whether the USH1 proteins are involved in common hair bundle morphogenetic processes is unknown. Here, we show that mouse models for the five USH1 genetic forms share hair bundle morphological defects. Hair bundle fragmentation and misorientation (25-52° mean ki…
Use of gases to improve survival of Bifidobacterium bifidum by modifying redox potential in fermented milk
2011
The aim of this work was to study the effect of the oxidoreduction potential, modified using gas, on the growth and survival of a probiotic strain, Bifidobacterium bifidum, and 2 yogurt strains, Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. Three fermented milks were manufactured with an initial oxidoreduction potential value adjusted to +440 mV (control milk), +350 mV (milk gassed with N(2)), and -300 mV [milk gassed with N(2) plus 4% (vol/vol) H(2) (N(2)-H(2))]. Acidification profiles, growth during milk fermentation and survival during storage at 4 °C for 28 d were determined. This study showed that fermented probiotic dairy products made from milk gassed with…
IMPROVED PRODUCTION OF THE ANTIBIOTIC ACTINORHODIN IN STREPTOMYCES COELICOLOR IMMOBILIZED-MYCELIAL CELL CULTIVATIONS
2017
Objectives i) Evaluation of ACT production in Streptomyces coelicolor M145 mycelial cells immobilized on polycaprolactone (PCL) and polylactic acid (PLA) nanofiber membranes, modified or not by an O2- plasma treatment. ii) Identification of gene products associated with the improvement of ACT production.
Pesticide Effects on Eel Metabolism
1995
Previous works on endosulfan eel toxicology in this laboratory demonstrated that 0.041 mg/liter of endosulfan was the 50% lethal concentration of 96 hr exposure. Eels of species Anguilla anguilla were exposed to two sublethal endosulfan concentrations: 8.2 μg/liter (1/5 LC50) and 4.1 μg/liter (1/10 LC50), and the experiment was done at different exposure times: 12, 24, 48, 72, and 96 hr. Muscle glycogen content decreased significantly (P < 0.05) at 24, 48, 72, and 96 hr exposure to 8.2 μg/liter pesticide; levels did not decline at any time when animals were exposed to 4.1 μg/liter. Muscle lactate levels in fish did not change significantly while lactate levels in eel blood increased at 12, …
Risk of Contracting COVID-19, Personal Resources and Subjective Well-Being among Healthcare Workers: The Mediating Role of Stress and Meaning-Making
2021
The latest research suggests that the relationships between the risk of contracting COVID-19, personal resources and subjective well-being have rather an indirect character and can include the occurrence of mediating factors related to meaning-making processes and stress experiences. Protection motivation theory offers a theoretical paradigm that enables these associations to be thoroughly investigated and understood. The current study aimed to examine the mediating roles of meaning-making and stress in the relationship of risk of contracting COVID-19 and personal resources (self-efficacy and meaning in life) with subjective well-being among healthcare workers. A total of 225 healthcare wor…
Preeclampsia: a defect in decidualization is associated with deficiency of Annexin A2.
2020
Background Decidualization defects in the endometrium have been demonstrated at the time of delivery in women with severe preeclampsia and to linger for years, which suggests a maternal contribution to the pathogenesis of this condition. Global transcriptional profiling reveals alterations in gene expression, which includes down-regulation of Annexin A2 in severe preeclampsia patients with decidualization resistance. Objective We investigated the functional role of Annexin A2 deficiency during endometrial decidualization and its potential contribution to shallow trophoblast invasion during implantation and subsequent placentation using in vitro and in vivo modeling. Study Design Annexin A2 …
Sympathetic neurons can produce and respond to interleukin 6
1998
Neuronal expression of cytokines is an area of active investigation in the contexts of development, disease, and normal neural function. Although cultured rat sympathetic neurons respond very weakly to exogenous interleukin 6 (IL-6), we find that addition of soluble IL-6 receptor (sIL-6R) and IL-6 enhances neuronal survival in the absence of nerve growth factor. Neutralizing monoclonal antibodies against IL-6 block these effects. Addition of IL-6 and sIL-6R also induces a subset of neuropeptide and transmitter synthetic enzyme mRNAs identical to that demonstrated for leukemia inhibitory factor, ciliary neurotrophic factor, and oncostatin M. Both of these effects are duplicated by addition o…
Topotecan triggers apoptosis in p53-deficient cells by forcing degradation of XIAP and survivin thereby activating caspase-3-mediated Bid cleavage.
2009
The topoisomerase I inhibitor topotecan (TPT) is used in the therapy of different tumors including high-grade gliomas. We previously showed that TPT-induced apoptosis depends on p53 with p53 wild-type (wt) cells being more resistant because of p53-controlled degradation of topoisomerase I. Here, we show that p53-deficient (p53(-/-)) fibroblasts undergo excessive mitochondrial apoptosis featuring H2AX phosphorylation, Bcl-x(L) decline, cytochrome c release, caspase-9/-3/-2 activation, and cleavage of Bid. In wt and apaf-1(-/-) cells, caspase-2 did not become activated and Bid was not cleaved. In addition, p53(-/-) cells cotreated with TPT and caspase-3 inhibitor showed neither caspase-2 acti…
Karyopherin Msn5 is involved in a novel mechanism controlling the cellular level of cell cycle regulators Cln2 and Swi5
2019
ABSTRACT The yeast β-karyopherin Msn5 controls the SBF cell-cycle transcription factor, responsible for the periodic expression of CLN2 cyclin gene at G1/S, and the nuclear export of Cln2 protein. Here we show that Msn5 regulates Cln2 by an additional mechanism. Inactivation of Msn5 causes a severe reduction in the cellular content of Cln2. This occurs by a post-transcriptional mechanism, since CLN2 mRNA level is not importantly affected in asynchronous cultures. Cln2 stability is not significantly altered in msn5 cells and inactivation of Msn5 causes a reduction in protein level even when Cln2 is stabilized. Therefore, the reduced amount of Cln2 in msn5 cells is mainly due not to a higher …
Contactus adherens, a special type of plaque-bearing adhering junction containing M-cadherin, in the granule cell layer of the cerebellar glomerulus.
1995
In the glomeruli of the granule cell layer of mammalian cerebellum, neuronal extensions are interconnected by numerous small, nearly isodiametric (diameters up to 0.1 micron), junctions previously classified as puncta adherentia related to the vinculin-containing, actin microfilament-anchoring junctions of the zonula adherens of epithelial and certain other cells. Using immunofluorescence and immunoelectron microscopy, we have found, however, that these junctions are negative for E- and VE-cadherin, for desmosomal cadherins, and also for vinculin, alpha-actinin, and desmoplakin, but they do contain, in addition to the protein plakoglobin common to all forms of adhering junctions, the plaque…