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91.
Tramontina F Tramontina AC Souza DF Leite MC Gottfried C Souza DO Wofchuk ST Gonçalves CA 《Cellular and molecular neurobiology》2006,26(1):81-86
Summary
相似文献
1. | S100B is a calcium-binding protein expressed and secreted by astrocytes, which has been implicated in glial-neuronal communication. Extracellular S100B appears to protect hippocampal neurons against toxic concentrations of glutamate. Here we investigated a possible autocrine role of S100B in glutamate uptake activity. |
2. | Astrocyte cultures were prepared of hippocampi from neonate Wistar rats. [3H] Glutamate uptake was measured after addition of S100B protein, antibody anti-S100B or TRTK-12, a peptide that blocks S100B activity mediated by the C-terminal region. |
3. | Antibody anti-S100B addition decreased glutamate uptake measured 30 min after medium replacement, without affecting cell integrity or viability. Moreover, low levels of S100B (less than 0.1 ng/mL) stimulated glutamate uptake measured immediately after medium replacement. |
4. | This finding reinforces the importance of astrocytes in the glutamatergic transmission, particularly the role of S100B neuroprotection against excitotoxic damage. |
92.
From the crop of the medicinal leech, Hirudo medicinalis, only Aeromonas veronii bv. sobria can be cultured consistently. Serum-sensitive A. veronii mutants were unable to colonize H. medicinalis, indicating the importance of the mammalian complement system for this unusual simplicity. Complementation of one selected mutant restored its ability to colonize. Serum-sensitive mutants are the first mutant class with a colonization defect for this symbiosis. 相似文献
93.
Stacey Llewellyn Tawin Inpankaew Susana Vaz Nery Darren J. Gray Jaco J. Verweij Archie C. A. Clements Santina J. Gomes Rebecca Traub James S. McCarthy 《PLoS neglected tropical diseases》2016,10(1)
Background
Accurate quantitative assessment of infection with soil transmitted helminths and protozoa is key to the interpretation of epidemiologic studies of these parasites, as well as for monitoring large scale treatment efficacy and effectiveness studies. As morbidity and transmission of helminth infections are directly related to both the prevalence and intensity of infection, there is particular need for improved techniques for assessment of infection intensity for both purposes. The current study aimed to evaluate two multiplex PCR assays to determine prevalence and intensity of intestinal parasite infections, and compare them to standard microscopy.Methodology/Principal Findings
Faecal samples were collected from a total of 680 people, originating from rural communities in Timor-Leste (467 samples) and Cambodia (213 samples). DNA was extracted from stool samples and subject to two multiplex real-time PCR reactions the first targeting: Necator americanus, Ancylostoma spp., Ascaris spp., and Trichuris trichiura; and the second Entamoeba histolytica, Cryptosporidium spp., Giardia. duodenalis, and Strongyloides stercoralis. Samples were also subject to sodium nitrate flotation for identification and quantification of STH eggs, and zinc sulphate centrifugal flotation for detection of protozoan parasites. Higher parasite prevalence was detected by multiplex PCR (hookworms 2.9 times higher, Ascaris 1.2, Giardia 1.6, along with superior polyparasitism detection with this effect magnified as the number of parasites present increased (one: 40.2% vs. 38.1%, two: 30.9% vs. 12.9%, three: 7.6% vs. 0.4%, four: 0.4% vs. 0%). Although, all STH positive samples were low intensity infections by microscopy as defined by WHO guidelines the DNA-load detected by multiplex PCR suggested higher intensity infections.Conclusions/Significance
Multiplex PCR, in addition to superior sensitivity, enabled more accurate determination of infection intensity for Ascaris, hookworms and Giardia compared to microscopy, especially in samples exhibiting polyparasitism. The superior performance of multiplex PCR to detect polyparasitism and more accurately determine infection intensity suggests that it is a more appropriate technique for use in epidemiologic studies and for monitoring large-scale intervention trials. 相似文献94.
Enayatizamir N Tabandeh F Rodríguez-Couto S Yakhchali B Alikhani HA Mohammadi L 《Bioresource technology》2011,102(22):10359-10362
The in vivo biodegradation of the diazo dye Reactive Black 5 (RB5) by Phanerochaete chrysosporium immobilised on cubes of nylon sponge and on sunflower-seed shells (SS) in laboratory-scale bioreactors was investigated. The SS cultivation led to the best results with a decolouration percentage of 90.3% in 72 h for an initial RB5 concentration of 100 mg/L. It was found that the addition of 0.4 mM veratryl alcohol (VA) into the medium considerably increased the decolouration rate in SS cultivation. However, the addition of VA had no effect in the nylon cultivation. Thin layer chromatography (TLC) revealed that RB5 was transformed into one metabolite after 24 h. UV-vis spectroscopy and Fourier Transform Infrared (FT-IR) also confirmed the biodegradation of RB5. Toxicity of RB5 solutions before and after fungal treatment was assayed using Sinorhizobium meliloti as a sensitive soil microorganism. P. chrysosporium transformed the toxic dye RB5 into a non-toxic product. 相似文献
95.
Susana Ruiz‐Ruiz Sergio Sanchez‐Carrillo Sergio Ciordia María C. Mena Celia Mndez‐García David Rojo Rafael Bargiela Elisa Zubeldia‐Varela Mnica Martínez‐Martínez Coral Barbas Manuel Ferrer Andrs Moya 《Aging cell》2020,19(1)
Composition of the gut microbiota changes during ageing, but questions remain about whether age is also associated with deficits in microbiome function and whether these changes occur sharply or progressively. The ability to define these deficits in populations of different ages may help determine a chronological age threshold at which deficits occur and subsequently identify innovative dietary strategies for active and healthy ageing. Here, active gut microbiota and associated metabolic functions were evaluated using shotgun proteomics in three well‐defined age groups consisting of 30 healthy volunteers, namely, ten infants, ten adults and ten elderly individuals. Samples from each volunteer at intervals of up to 6 months (n = 83 samples) were used for validation. Ageing gradually increases the diversity of gut bacteria that actively synthesize proteins, that is by 1.4‐fold from infants to elderly individuals. An analysis of functional deficits consistently identifies a relationship between tryptophan and indole metabolism and ageing (p < 2.8e?8). Indeed, the synthesis of proteins involved in tryptophan and indole production and the faecal concentrations of these metabolites are directly correlated (r2 > .987) and progressively decrease with age (r2 > .948). An age threshold for a 50% decrease is observed ca. 11–31 years old, and a greater than 90% reduction is observed from the ages of 34–54 years. Based on recent investigations linking tryptophan with abundance of indole and other “healthy” longevity molecules and on the results from this small cohort study, dietary interventions aimed at manipulating tryptophan deficits since a relatively “young” age of 34 and, particularly, in the elderly are recommended. 相似文献
96.
Z Carvalho-Santos P Machado I Alvarez-Martins SM Gouveia SC Jana P Duarte T Amado P Branco MC Freitas ST Silva C Antony TM Bandeiras M Bettencourt-Dias 《Developmental cell》2012,23(2):412-424
Cilia and flagella are involved in a variety of processes and human diseases, including ciliopathies and sterility. Their motility is often controlled by?a central microtubule (MT) pair localized within the ciliary MT-based skeleton, the axoneme. We characterized the formation of the motility apparatus in detail in Drosophila spermatogenesis. We show that assembly of the central MT pair starts prior to the meiotic divisions, with nucleation of a singlet MT within the basal body of a small cilium, and that the second MT of the pair only assembles much later, upon flagella formation. BLD10/CEP135, a conserved player in centriole and flagella biogenesis, can bind and stabilize MTs and is required for the early steps of central MT pair formation. This work describes a genetically tractable system to study motile cilia formation and provides an explanation for BLD10/CEP135's role in assembling highly stable MT-based structures, such as motile axonemes and centrioles. 相似文献
97.
Soares JB Pimentel-Nunes P Afonso L Rolanda C Lopes P Roncon-Albuquerque R Gonçalves N Boal-Carvalho I Pardal F Lopes S Macedo G Lara-Santos L Henrique R Moreira-Dias L Gonçalves R Dinis-Ribeiro M Leite-Moreira AF 《Innate immunity》2012,18(5):700-708
We evaluated expression of TLR2, TLR4 and proinflammatory genes [NF-κB, TNF-α, cyclooxygenase-2 (COX-2)] in liver samples of patients in different stages of liver disease. Fifteen patients with unexplained transaminases elevation (reference group), 22 with viral chronic hepatitis (hepatitis group), 14 with virus-induced severe fibrosis/cirrhosis (cirrhosis group) and 10 with hepatocarcinoma (hepatocarcinoma group) were consecutively included in the study. Quantification of TLR2, TLR4, NF-κB, TNF-α and COX-2 mRNA was done by real-time RT-PCR and TLR2 and TLR4 protein expression was evaluated by immunohistochemistry. Compared with reference, TLR2 and TLR4 mRNA was increased in hepatitis (TLR2: 2.66?±?0.69; TLR4: 3.11?±?0.79; P?0.05) and cirrhosis (TLR2: 2.14?±?0.5; TLR4: 1.74?±?0.27; P?0.05) and decreased in hepatocarcinoma (TLR2: 0.48?±?0.15; TLR4: 0.54?±?0.10; P?0.05). This associated with increased TNF-α and COX-2 mRNA in hepatitis (TNF-α: 3.24?±?0.79; COX-2: 2.47?±?0.36; P?0.05) and cirrhosis (TNF-α: 1.73?±?0.28; COX-2: 1.8?±?0.35, P?0.05), whereas NF-κB mRNA was increased in hepatitis (2.42?±?0.31; P?0.05) and unchanged in cirrhosis (1.34?±?0.17; P?=?0.3). Hepatocarcinoma presented increased COX-2 mRNA (1.63?±?0.15; P?0.05) and maintained (at decreased levels) mRNA of NF-κB (0.52?±?0.12) and TNF-α (0.52?±?0.12; P?0.05, all genes). Immunohistochemistry confirmed increased expression of TLR2 and TLR4 in hepatitis and cirrhosis and maintained expression in hepatocarcinoma. Upregulation of TLR2, TLR4 and their proinflammatory mediators is associated with virus-induced hepatic IFC sequence. 相似文献
98.
Susana Gómez Escalante Joseph A. Brightmore Peter W. Piper Stefan H. Millson 《Cell stress & chaperones》2018,23(4):609-615
A dedicated UNC45, Cro1, She4 (UCS) domain-containing protein assists in the Hsp90-mediated folding of the myosin head. Only weak sequence conservation exists between the single UCS protein of simple eukaryotes (She4 in budding yeast) and the two UCS proteins of higher organisms (the general cell and striated muscle UNC45s; UNC45-GC and UNC45-SM, respectively). In vertebrates, UNC45-GC facilitates cytoskeletal functions, whereas the 55% identical UNC45-SM assists assembly of the contractile apparatus of cardiac and skeletal muscles. A Saccharomyces cerevisiae she4Δ mutant, totally lacking any UCS protein, was engineered to express as its sole Hsp90 either the Hsp90α or the Hsp90β isoforms of human cytosolic Hsp90. A transient induction of the human UNC45-GC, but not UNC45-SM, could rescue the defective endocytosis in these she4Δ cells at 39 °C, irrespective of whether they possessed Hsp90α or Hsp90β. UNC45-GC-mediated rescue of the localisation of a Myo5-green fluorescent protein (GFP) fusion to cortical patches at 39 °C was more efficient in the yeast containing Hsp90α, though this may relate to more efficient functioning of Hsp90α as compared to Hsp90β in these strains. Furthermore, inducible expression of UNC45-GC, but not UNC45-SM, could partially rescue survival at a more extreme temperature (45 °C) that normally causes she4Δ mutant yeast cells to lyse. The results indicate that UCS protein function has been most conserved—yeast to man—in the UNC45-GC, not UNC45-SM. This may reflect UNC45-GC being the vertebrate UCS protein that assists formation of the actomyosin complexes needed for cytokinesis, cell morphological change, and organelle trafficking—events also facilitated by the myosins in yeast. 相似文献
99.
Susana Pascoal Joana Esteves de Lima Jonathan D. Leslie Simon M. Hughes Leonor Saúde 《PloS one》2013,8(6)
Background
Accurate regulation of Notch signalling is central for developmental processes in a variety of tissues, but its function in pectoral fin development in zebrafish is still unknown.Methodology/Principal Findings
Here we show that core elements necessary for a functional Notch pathway are expressed in developing pectoral fins in or near prospective muscle territories. Blocking Notch signalling at different levels of the pathway consistently leads to the formation of thin, wavy, fragmented and mechanically weak muscles fibres and loss of stress fibres in endoskeletal disc cells in pectoral fins. Although the structural muscle genes encoding Desmin and Vinculin are normally transcribed in Notch-disrupted pectoral fins, their proteins levels are severely reduced, suggesting that weak mechanical forces produced by the muscle fibres are unable to stabilize/localize these proteins. Moreover, in Notch signalling disrupted pectoral fins there is a decrease in the number of Pax7-positive cells indicative of a defect in myogenesis.Conclusions/Significance
We propose that by controlling the differentiation of myogenic progenitor cells, Notch signalling might secure the formation of structurally stable muscle fibres in the zebrafish pectoral fin. 相似文献100.
Victor M. Victor Susana Rovira-Llopis Vanessa Saiz-Alarcon Maria C. Sangüesa Luis Rojo-Bofill Celia Ba?uls Rosa Falcón Raquel Castelló Luis Rojo Milagros Rocha Antonio Hernández-Mijares 《PloS one》2014,9(9)