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1.
Michael M. Lipsky Talia R. Sheridan Richard O. Bennett Eric B. May 《In vitro cellular & developmental biology. Plant》1986,22(6):360-362
Summary Comparisons were made of attachment and viability of rainbow trout (Salmo gairdneri) hepatocytes in short-term (2 days), primary culture on plastic, collagen-coated or extracellular matrix (ECM) coated dishes.
Hepatocyte isolation routinely yielded cells with good viability (96%). Cells plated on ECM attached with high efficiency
(93%) in contrast to cells cultured on plastic or collagen (∼20%). The cells plated on ECM flattened out and formed monolayers,
while the cells on plastic and collagen rounded up and formed multi-cell aggregates in suspension. Viability of cells in all
substrates remained high over the 2 day culture period. ECM is the first substrate to support trout-hepatocyte attachment
in primary culture. Differentiated liver function was maintained in cells cultured on ECM as evidence by the induction of
tyrosine aminotransferase by hydrocortisone (200%).
This work was supported in part by research grant R809599010 from the U. S. Environmental Protection Agency.
Editor's Statement This paper reports improved methods for culture of trout liver-derived cells that make in vitro investigations
of fish metabolism, carcinogenesis and chemical toxicity more feasible than previously applied techniques. Recent interest
in fish as models for study and indicators of effects of envionmental and food-related toxins make this work timely, poarticularly
since many of the compounds of interest are primarily metabolized by hepatocytes or act on liver as a major target. David
W. Barnes 相似文献
2.
A Lanas J Alcalde M Montoro F Gomollon J Morandeira J Bueno R Sainz 《Revista Espanola de Fisiología》1985,41(3):335-339
Gastrin serum levels after acidification of the second portion of the duodenum were studied, in dogs and humans, while simultaneously measuring secretin levels and gastric acid secretion. After duodenal acidification in dogs, a 50% inhibition of gastric acid secretion with parallel 100% increases in the serum secretin levels was noted whereas gastrin serum levels did not change (after duodenal acidification). In humans, a 25% inhibition of gastric acid secretion with parallel 50% (not significative) increases in the secretin serum levels was noted. In the entire group gastrin levels did not change, but in 35.2% of the subjects a little increment without statistical significance was noted. It is concluded that the inhibition mechanism of gastric acid secretion after duodenal acidification is more important in dog than in man, and that, probably, gastrin does not play an important role in this mechanism. 相似文献
3.
4.
Talia Fuchs Julian N. Trollor John Crawford David A. Brown Bernhard T. Baune Katherine Samaras Lesley Campbell Samuel N. Breit Henry Brodaty Perminder Sachdev Evelyn Smith 《Aging cell》2013,12(5):882-889
Higher levels of macrophage inhibitory cytokine‐1, also known as growth differentiation factor 15 (MIC‐1/GDF15), are associated with adverse health outcomes and all‐cause mortality. The aim of this study was to examine the relationships between MIC‐1/GDF15 serum levels and global cognition, five cognitive domains, and mild cognitive impairment (MCI), at baseline (Wave 1) and prospectively at 2 years (Wave 2), in nondemented participants aged 70–90 years. Analyses were controlled for age, sex, education, Framingham risk score, history of cerebrovascular accident, acute myocardial infarction, angina, cancer, depression, C‐reactive protein, tumor necrosis factor‐α, interleukins 6 and 12, and apolipoprotein ε4 genotype. Higher MIC‐1/GDF15 levels were significantly associated with lower global cognition at both waves. Cross‐sectional associations were found between MIC‐1/GDF15 and all cognitive domains in Wave 1 (all P < 0.001) and between processing speed, memory, and executive function in Wave 2 (all P < 0.001). Only a trend was found for the prospective analyses, individuals with high MIC‐1/GDF15 at baseline declined in global cognition, executive function, memory, and processing speed. However, when categorizing MIC‐1/GDF15 by tertiles, prospective analyses revealed statistically significant lower memory and executive function in Wave 2 in those in the upper tertile compared with the lower tertile. Receiver operating characteristics (ROC) analysis was used to determine MIC‐1/GDF15 cutoff values associated with cognitive decline and showed that a MIC‐1/GDF15 level exceeding 2764 pg/ml was associated with a 20% chance of decline from normal to MCI or dementia. In summary, MIC‐1/GDF15 levels are associated with cognitive performance and cognitive decline. Further research is required to determine the pathophysiology of this relationship. 相似文献
5.
D. P. Gladue V. O'Donnell R. Baker-Branstetter L. G. Holinka J. M. Pacheco I. Fernández Sainz Z. Lu X. Ambroggio L. Rodriguez M. V. Borca 《Journal of virology》2013,87(12):6794-6803
Foot-and-mouth disease virus (FMDV), the causative agent of foot-and-mouth disease, is an Aphthovirus within the Picornaviridae family. During infection with FMDV, several host cell membrane rearrangements occur to form sites of viral replication. FMDV protein 2C is part of the replication complex and thought to have multiple roles during virus replication. To better understand the role of 2C in the process of virus replication, we have been using a yeast two-hybrid approach to identify host proteins that interact with 2C. We recently reported that cellular Beclin1 is a natural ligand of 2C and that it is involved in the autophagy pathway, which was shown to be important for FMDV replication. Here, we report that cellular vimentin is also a specific host binding partner for 2C. The 2C-vimentin interaction was further confirmed by coimmunoprecipitation and immunofluorescence staining to occur in FMDV-infected cells. It was shown that upon infection a vimentin structure forms around 2C and that this structure is later resolved or disappears. Interestingly, overexpression of vimentin had no effect on virus replication; however, overexpression of a truncated dominant-negative form of vimentin resulted in a significant decrease in viral yield. Acrylamide, which causes disruption of vimentin filaments, also inhibited viral yield. Alanine scanning mutagenesis was used to map the specific amino acid residues in 2C critical for vimentin binding. Using reverse genetics, we identified 2C residues that are necessary for virus growth, suggesting that the interaction between FMDV 2C and cellular vimentin is essential for virus replication. 相似文献
6.
Sergio Serrano-Villar Talia Sainz Zhong-Min Ma Netanya S. Utay Tae-Wook Chun Surinder Mann Angela D. Kashuba Basile Siewe Anthony Albanese Paolo Troia-Cancio Elizabeth Sinclair Anoma Somasunderam Tammy Yotter Steven G. Deeks Alan Landay Richard B. Pollard Christopher J. Miller Santiago Moreno David M. Asmuth 《PLoS pathogens》2016,12(3)
7.
Seasonality of Antarctic minke whale (Balaenoptera bonaerensis) calls off the western Antarctic Peninsula 下载免费PDF全文
The Antarctic minke whale (Balaenoptera bonaerensis) is a difficult species to study because of its low visual detectability and preference for living within the sea ice habitat, accessible only by ice‐strengthened vessels. Recent identification of the Antarctic minke whale as the source of the seasonally ubiquitous bio‐duck call has allowed the use of this sound, as well as downsweeps, to investigate seasonality trends and diel patterns in Antarctic minke whale call production, and their relationship to sea ice cover. Passive acoustic data were collected using an autonomous Acoustic Recording Package (ARP) off the western Antarctic Peninsula. Bio‐duck calls were classified into four distinct call variants, with one variant having two subtypes. Bio‐duck calls were detected between April and November, with increasing call duration during the austral winter, indicating a strong seasonality in call production. Downsweeps, which were also attributed to Antarctic minke whales, were present throughout most months during the recording period, with a peak in July, and an absence in March and April. Both bio‐duck and downsweeps were significantly correlated with sea ice cover. No diel patterns were observed in bio‐duck calls or in downsweep call production at this site. 相似文献
8.
Erica J. Fratz-Berilla Talia Faison Casey L. Kohnhorst Sai Rashmika Velugula-Yellela David N. Powers Kurt Brorson Cyrus Agarabi 《Biotechnology and bioengineering》2019,116(12):3242-3252
Mycoplasma contamination events in biomanufacturing facilities can result in loss of production and costly cleanups. Mycoplasma may survive in mammalian cell cultures with only subtle changes to the culture and may penetrate the 0.2 µm filters often used in the primary clarification of harvested cell culture fluid. Culture cell-based and indicator cell-based assays that are used to detect mycoplasma are highly sensitive but can take up to 28 days to complete and cannot be used for real-time decision making during the biomanufacturing process. To support real-time measurements of mycoplasma contamination, there is a push to explore nucleic acid testing. However, cell-based methods measure growth or colony forming units and nucleic acid testing measures genome copy number; this has led to ambiguity regarding how to compare the sensitivity of the methods. In addition, the high risk of conducting experiments wherein one deliberately spikes mycoplasma into bioreactors has dissuaded commercial groups from performing studies to explore the multiple variables associated with the upstream effects of a mycoplasma contamination in a manufacturing setting. Here we studied the ability of Mycoplasma arginini to persist in a single-use, perfusion rocking bioreactor system containing a Chinese hamster ovary (CHO) DG44 cell line expressing a model monoclonal immunoglobulin G1 (IgG1) antibody. We examined M. arginini growth and detection by culture methods, as well as the effects of M. arginini on mammalian cell health, metabolism, and productivity. We compared process parameters and controls normally measured in bioreactors including dissolved oxygen, gas mix, and base addition to maintain pH, to examine parameter changes as potential indicators of contamination. Our work showed that M. arginini affects CHO cell growth profile, viability, nutrient consumption, oxygen use, and waste production at varying timepoints after M. arginini introduction to the culture. Importantly, how the M. arginini contamination impacts the CHO cells is influenced by the concentration of CHO cells and rate of perfusion at the time of M. arginini spike. Careful evaluation of dissolved oxygen, pH control parameters, ammonia, and arginine over time may be used to indicate mycoplasma contamination in CHO cell cultures in a bioreactor before a read-out from a traditional method. 相似文献
9.
Much is known about yeast metabolism and the kinetics of industrial batch fermentation processes. In this study, however, we provide the first tool to evaluate the dynamic interaction that exists between them. A stoichiometric model, using wine fermentation as a case study, was constructed to simulate batch cultures of Saccharomyces cerevisiae. Five differential equations describe the evolution of the main metabolites and biomass in the fermentation tank, while a set of underdetermined linear algebraic equations models the pseudo-steady-state microbial metabolism. Specific links between process variables and the reaction rates of metabolic pathways represent microorganism adaptation to environmental changes in the culture. Adaptation requirements to changes in the environment, optimal growth, and homeostasis were set as the physiological objectives. A linear programming routine was used to define optimal metabolic mass flux distribution at each instant throughout the process. The kinetics of the process arise from the dynamic interaction between the environment and metabolic flux distribution. The model assessed the effect of nitrogen starvation and ethanol toxicity in wine fermentation and it was able to simulate fermentation profiles qualitatively, while experimental fermentation yields were reproduced successfully as well. 相似文献
10.
Manuel J. Lpez‐Rodríguez Ignacio Peralta‐Maraver Brunella Gaetani Carmen E. Sainz‐Cantero Romolo Fochetti J. Manuel Tierno de Figueroa 《International Review of Hydrobiology》2012,97(6):485-496
In this work we present the results of a one‐year study on the macroinvertebrate community in an intermittent stream in southern Spain. We have studied the taxonomic composition, diversity and food web monthly in order to consider temporal variability in these parameters. More than 60 macroinvertebrate taxa have been recorded in the stream, but they do not cohabit at the same time. Many of them join the community at the beginning of the wet period. Afterwards, some new taxa incorporate but some others disappear. This leads to huge fluctuations in the diversity of the community and in the food web of different sampling dates. These variations are linked to environmental disturbances, mainly to flow peaks and minimums. From a relatively well structured, but simple, food web at the beginning of the wet period, it can be seen how several trophic levels disappear with time, and how several organisms change or extend their trophic function within it. We relate these variations to the intermediate disturbance hypothesis and discuss the resilience of the community of this intermittent stream (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献