scholarly journals Cellular water analysis in T cells reveals a switch from metabolic water gain to water influx

2020 ◽  
Author(s):  
A Saragovi ◽  
T Zilberman ◽  
G Yasur ◽  
K Turjeman ◽  
I Abramovich ◽  
...  
Keyword(s):  
T Cells ◽  
Cell Growth ◽  
Water Content ◽  
Water Mass ◽  
Slow Phase ◽  
Second Phase ◽  
Water Influx ◽  
Cellular Water ◽  
Water Gain ◽  
Metabolic Water

AbstractCell growth is driven by the acquisition and synthesis of dry biomass and water mass. This study examines the increase of water in T cells biomass during cell growth. We found that T cell growth is initiated by a phase of slow increase of cellular water, followed by a second phase of rapid increase in water content. To study the origin of the water gain, we developed a novel method, Cold Aqua Trap – Isotope Ratio Mass Spectrometry (CAT-IRMS), which allows analysis of intracellular water isotope composition. Applying CAT-IRMS, we discovered that glycolysis-coupled metabolic water accounts on average for 11 femtoliter (fL) out of the 20 fL of water gained per cell during the slow phase. At the end of the rapid phase, before initiation of cell division, a water influx occurs, increasing the water level by three-fold. Thus, activated T cells switch from acquiring metabolic water to incorporating water from the extracellular medium. Our work provides a method to analyze cell water content and an insight into the way cells regulate their water mass.

scholarly journals Validation of the Labeled-Water Method for Estimating Food Consumption in Nestling Herons

The Auk ◽  
2002 ◽  
Vol 119 (2) ◽  
pp. 551-556
Author(s):  
Johanna H. Salatas ◽  
Peter C. Frederick ◽  
Kenneth A. Nagy ◽  
Gary E. Williams
Keyword(s):  
Water Content ◽  
Food Consumption ◽  
Average Error ◽  
Ecological Studies ◽  
Influx Rate ◽  
Water Influx ◽  
Isotope Method ◽  
Errors Analysis ◽  
Metabolic Water ◽  
Good Agreement

Abstract Accurate measurements of food consumption by young birds are of great value in a variety of ecological studies, but traditional measurement methods are problematic and prone to high error. In animals that obtain their water primarily through food, it is possible to estimate food consumption from measurements of water influx rate, using radioactively labeled water (3H2O), and diet water content. We evaluated that method by comparing actual food consumption with simultaneous estimates of food consumption based on the labeled-water method in captive-reared nestling Tricolored Herons (Egretta tricolor). There was good agreement. The average error in the isotope method was −2% (SD = 8%), and that difference was not statistically significant. An errors analysis indicated that the accuracy of this method is sensitive to determinations of dietary water content and animal body water content, and to estimates of rates of metabolic water production and unidirectional water vapor input.

scholarly journals Knockdown of Mgat5 Inhibits Breast Cancer Cell Growth with Activation of CD4+ T Cells and Macrophages

2008 ◽  
Vol 180 (5) ◽  
pp. 3158-3165 ◽  
Author(s):  
Dongqing Li ◽  
Yanmei Li ◽  
Xianglei Wu ◽  
Qiao Li ◽  
Jing Yu ◽  
...  
Keyword(s):  
Breast Cancer ◽  
T Cells ◽  
Cell Growth ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Cd4 T Cells ◽  
Cancer Cell Growth ◽  
Breast Cancer Cell Growth

The Utilisation of metabolic Water in Insects

1944 ◽  
Vol 35 (2) ◽  
pp. 127-139 ◽  
Author(s):  
G. Fraenkel ◽  
M. Blewett
Keyword(s):  
Body Weight ◽  
Water Content ◽  
Larval Development ◽  
Dry Weight ◽  
Larval Period ◽  
Tribolium Confusum ◽  
Ephestia Kuehniella ◽  
Final Size ◽  
Metabolic Water ◽  
Food Consumed

(1) Three insects,Tribolium confusum, Ephestia kuehniellaandDermestes vulpinus, have been grown at several humidities and the following factors have been determined: length of larval period; water content of food and of the freshly formed pupae; wet and dry weight of pupae and wet and dry weight of food consumed during larval development. The “net utilisation” of the food has been calculated as the ratio of dry weight of food eaten per larva to dry weight of pupa.(2) At lower humidities more food is eaten to produce a given unit of body weight. The length of the larval period increases and the weight of the pupae decreases.(3) More food is eaten at low humidities, because part of the food is utilised as water. As a consequence of this, the larva grows more slowly and its final size is smaller. It is shown forDermestesat 30 per cent. andEphestiaat 1 per cent. R.H. that less than 32·9 and 7·6 per cent. of the water in the pupae can be derived from water ingested with the food.

scholarly journals A multiscale approach to estimate the cellular diffusivity during food drying

2021 ◽  
Author(s):  
Zachary G Welsh
Keyword(s):  
Water Content ◽  
Effective Diffusivity ◽  
Theoretical Models ◽  
Intracellular Water ◽  
Cellular Heterogeneity ◽  
Multiscale Approach ◽  
Multiscale Models ◽  
Drying Model ◽  
Cellular Water ◽  
Multiscale Homogenization

Theoretical models for food drying commonly utilize an effective diffusivity solved through curve fitting based on experimental data. This creates models with limited predictive capabilities. Multiscale modeling is one approach which can help transition to a more physics-based model minimizing the empirical information required while improving a model’s predictive capabilities. However, to enable an accurate scaling operation, multiscale models require diffusivity at a fine scale (microscale). Measuring these properties is experimentally costly and time consuming as they are often temperature and/or moisture dependent. This research conducts an inverse analysis on a multiscale homogenization food drying model to deduce the temporal diffusivity of intracellular water. A representation of the real cellular water breakdown was considered and appropriate assumptions to represent its cellular heterogeneity, in relation to time, were investigated. The work uncovered that a linear decrease in intracellular water content could be assumed and thus a function for its diffusivity was developed. The proposed function is in terms of sample temperature and intracellular water content opening the possibilities to be applied to various food materials.

Ventricular performance and myocardial water content during hemodilution in dogs

1978 ◽  
Vol 235 (6) ◽  
pp. H767-H775 ◽  
Author(s):  
G. A. Geffin ◽  
M. A. Vasu ◽  
D. D. O'Keefe ◽  
D. G. Pennington ◽  
A. J. Erdmann ◽  
...  
Keyword(s):  
Water Content ◽  
Diastolic Pressure ◽  
Left Ventricular ◽  
Lv Function ◽  
Stroke Work ◽  
Ventricular Performance ◽  
End Diastolic Volume ◽  
Lv Mass ◽  
Right Heart Bypass ◽  
Water Gain

In dogs anesthetized with chloralose-urethan on right heart bypass, left ventricular (LV) performance was assessed at constant LV stroke work before and for up to 2.5 h after crystalloid hemodilution was established. Lowering the hematocrit from 43.3 +/- 1.3% to 13.6 +/- 1.7% (SE) did not significantly change LV end-diastolic pressure (LVEDP) initially. After 80 min LVEDP increased slightly by 1.7 +/- 0.6 cmH2O (P less than 0.05) at a stroke work of 17.3 +/- 2.3 g.m. The value of dP/dt did not change significantly throughout. When LV function curves were generated by increasing cardiac output, the stroke work attained at an LVEDP of 10 cmH2O decreased with hemodilution from 23.9 +/- 3.5 to 20.8 +/- 3.9 g.m (NS). LV wall water content increased with hemodilution, from which it could be calculated that there was an 18.6% increase in LV mass. Thus, despite an increase in LV external girth demonstrated by LV circumferential gauges, it is possible that increased wall thickness due to the water gain resulted in little change or an actual decrease in LV end-diastolic volume. Thus, profound hemodilution can be attained with only slight depression of LV performance.

scholarly journals A new method for the detection of Lesch-Nyhan heterozygotes by peripheral blood T cell culture using T cell growth factor

Blood ◽  
1984 ◽  
Vol 63 (4) ◽  
pp. 912-916 ◽  
Author(s):  
N Kamatani ◽  
H Yamanaka ◽  
K Nishioka ◽  
T Nakamura ◽  
K Nakano ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Growth Factor ◽  
Cell Growth ◽  
Peripheral Blood ◽  
Normal Individuals ◽  
T Cell Growth ◽  
Hypoxanthine Guanine Phosphoribosyltransferase ◽  
T Lymphoblasts ◽  
T Cell Growth Factor

Abstract Thioguanine-resistant T lymphoblast populations were selectively amplified using T cell growth factor in the cultures of peripheral blood T cells from four Lesch-Nyhan heterozygotes. Although Lesch-Nyhan T lymphoblasts were all thioguanine-resistant, none of the cultures from 13 control subjects yielded the growth of such defective cell populations. These data provide direct evidence for the existence of a small percentage (5%–40%) of hypoxanthine-guanine phosphoribosyltransferase (HGPRT) deficient T cells in the heterozygotes, but not in normal individuals. Conversely, culture of the T lymphoblasts with azaserine plus hypoxanthine permitted the growth of the other part of the cell population that was enzyme positive. The low percentages of HGPRT-negative cells among T cells in heterozygotes suggest that the presence of this enzyme is beneficial for differentiation of lymphocytes of T cell linkage. Considering the ease and the reliability, culture of the peripheral T cells with thioguanine and T cell growth factor is very likely of practical use for detecting Lesch-Nyhan syndrome carriers among predisposed females.

scholarly journals Association between clonogenic cell growth and clinical risk group in B- cell chronic lymphocytic leukemia

Blood ◽  
1990 ◽  
Vol 76 (1) ◽  
pp. 142-149 ◽  
Author(s):  
R Dadmarz ◽  
SN Rabinowe ◽  
SA Cannistra ◽  
JW Andersen ◽  
AS Freedman ◽  
...  
Keyword(s):  
T Cells ◽  
High Risk ◽  
Cell Growth ◽  
Chronic Lymphocytic Leukemia ◽  
B Cell ◽  
Risk Groups ◽  
Lymphocytic Leukemia ◽  
Cloning Efficiency ◽  
Activated T Cells ◽  
Clonogenic Cells

Abstract Chronic lymphocytic leukemia of B-cell origin (B-CLL) is a disease with a variable clinical course, despite the fact that the neoplastic cells in this disorder are homogeneous with respect to morphology, immunophenotype, and cell cycle stage. To further investigate the heterogeneity observed in the clinical behavior of B-CLL, we determined the phenotype and growth requirements of clonogenic cells from 28 patients with B-CLL from low-, intermediate-, and high-risk groups as defined by the Rai staging system. Using methyl-cellulose as a semi- solid media with feeder cells and/or growth factors, colonies were observed with one or more of the culture conditions tested in 25 of 28 CLLs. Phenotypic analysis of colonies demonstrated that the clonogenic cells uniformly expressed la, CD19, CD20, CD5, and the identical light chain as the original CLL cell cultured. However, heterogeneity was observed in clonogenic B-CLL cell growth among the three different CLL risk groups. Clonogenic cells from patients with low-risk CLL required either irradiated unstimulated T cells, with or without conditioned media (CM) or irradiated activated T cells alone for colony formation. Both the number of colonies (227 +/- 15) as well as the number of cells per colony (220 +/- 82) were large, with a mean cloning efficiency of 0.39%. In contrast, clonogenic cells from patients with intermediate- and high-risk CLL required the combination of both irradiated activated T cells and CM. As compared with the low-risk CLLs, both the number and size of the colonies formed by the intermediate- (74 +/- 17, 70 +/- 39) and high- (83 +/- 28, 40 +/- 14) risk groups were significantly lower (P less than .0001). Similarly, the mean cloning efficiency was significantly reduced to 0.15% and 0.14%, respectively. None of the recombinant cytokines (interleukin 1 [IL-1] to IL-7, tumor necrosis factor, alpha and gamma-interferon, B-cell growth factor, and granulocyte macrophage colony-stimulating factor) alone or in combination with each other could entirely replace the stimulatory effect of the activated T cells. These data suggest that clinical progression of B-CLL is associated with a loss of clonogenic potential in the circulating pool of neoplastic cells, which require as yet undefined factors provided by activated T cells and CM.

De-coupling seasonal changes in water content and dry matter to predict live conifer foliar moisture content

2014 ◽  
Vol 23 (4) ◽  
pp. 480 ◽  
Author(s):  
W. Matt Jolly ◽  
Ann M. Hadlow ◽  
Kathleen Huguet
Keyword(s):  
Water Stress ◽  
Moisture Content ◽  
Water Content ◽  
Seasonal Variations ◽  
Seasonal Changes ◽  
Dry Matter ◽  
Water Mass ◽  
Water Status ◽  
Dry Mass ◽  
Dry Matter Partitioning

Live foliar moisture content (LFMC) significantly influences wildland fire behaviour. However, characterising variations in LFMC is difficult because both foliar mass and dry mass can change throughout the season. Here we quantify the seasonal changes in both plant water status and dry matter partitioning. We collected new and old foliar samples from Pinus contorta for two growing seasons and quantified their LFMC, relative water content (RWC) and dry matter chemistry. LFMC quantifies the amount of water per unit fuel dry weight whereas RWC quantifies the amount of water in the fuel relative to how much water the fuel can hold at saturation. RWC is generally a better indicator of water stress than is LFMC. We separated water mass from dry mass for each sample and we attempted to best explain the seasonal variations in each using our measured physiochemical variables. We found that RWC explained 59% of variation in foliar water mass. Additionally, foliar starch, sugar and crude fat content explained 87% of the variation in seasonal dry mass changes. These two models combined explained 85% of the seasonal variations in LFMC. These results demonstrate that changes to dry matter exert a stronger control on seasonal LFMC dynamics than actual changes in water content, and they challenge the assumption that LFMC variations are strongly related to water stress. This methodology could be applied across a range of plant functional types to better understand the factors that drive seasonal changes in LFMC and live fuel flammability.

scholarly journals Estabilidade osmótica dos fluídos celômicos de um pepino do mar (Holothuria grisea) e de uma estrela-do-mar (Asterina stellifera) (Echinodermata) expostos ao ar durante a maré baixa: um estudo de campo

2002 ◽  
Vol 31 ◽  
Author(s):  
DENILTON VIDOLIN ◽  
IVONETE A. SANTOS GOUVEA ◽  
CAROLINA A. FREIRE
Keyword(s):  
Body Wall ◽  
Sea Water ◽  
Weather Conditions ◽  
Coelomic Fluid ◽  
Slight Reduction ◽  
Air Exposure ◽  
Water Influx ◽  
Sunny Weather ◽  
Wall Permeability ◽  
Water Gain

Animais de entre-marés podem ser expostos ao ar durante a maré baixa, por pelo menos 1-2 horas. Os animais expostos ao ar são susceptíveis a perda de sal e/ou entrada de água durante chuva intensa, ou perda de água pela ação de dessecação do sol. A osmolalidade de amostras de fluido celômico obtidas do pepino-do-mar Holothuria grisea e da estrela-do-mar Asterina stellifera expostas ao ar, ou de animais controles imersos na água do mar adjacente foi determinada. As amostras foram obtidas imediatamente após a exposição ao ar, e novamente após uma hora de exposição ao ar, durante a maré baixa no campo, em tempo nublado, chuvoso, ou ensolarado, na Praia rochosa do Quilombo, Penha, Sul do Brasil. Uma hora de exposição a qualquer das condições climáticas indicadas não alterou a osmolalidade dos fluidos celômicos. Houve pequena redução nas osmolalidades dos fluidos celômicos durante a exposição ao ar com precipitação de chuva. Sugere-se que estes equinodermas possam imediatamente detectar sua exposição ao ar, e possam então reduzir a permeabilidade osmótica de sua parede do corpo, para evitar perda de água para o ar ou entrada de água/saída de sal durante a chuva. ABSTRACT Intertidal animals can be exposed to the air during low tide, for at least 1-2 hours. Animals exposed to the air are subject to salt loss (or water gain) from heavy rains or volume loss from the desiccating action of the sun. Coelomic fluid samples obtained from the sea-cucumber Holothuria grisea and the starfish Asterina stellifera exposed to the air or from control animals submerged in surrounding sea water have been assayed for osmolality. Samples were obtained right after air exposure and again after 1 hour of exposure to the air during low tide in the field, either under cloudy, rainy or sunny weather conditions, in the rocky beach of Quilombo, Penha, Southern Brazil. One hour of exposure to any of the conditions did not change coelomic fluid osmolalities. There was a slight reduction in coelomic fluid osmolalities upon air exposure during rainfall. It is suggested that these echinoderms can somehow immediately detect air exposure and reduce their body wall permeability to avoid water loss or water influx/salt loss during rainfall. RÉSUMÉ Animaux d’entre-marées peuvent êtres exposés a l’air libre pendant le reflux de la marée, pour environ une ou deux heures seulement. Ces animaux, quand exposés a l’air libre, sont susceptibles de perdre du sel et d’absorber de l’eau pendant une période de pluie intense. Par contre, ils peuvent perdre de l’eau si soumis a l’action de dessèchement due a une éxposition au soleil. On a réussi a determiner l’osmolalité d’échantillons du fluide celomique obtenus du Pépin-de-mer Holothuria grisea et de l’Étoile-de-mer Asterina stellifera exposés a l’air libre, e d’animaux-controles immergés dans l’eau de mer voisin. Les échantillons ont été obtenus tout de suite après l’exposition à l’air et, une seconde fois, après une heure d’exposition à l’air libre, pendant la durée de la marée basse, soit sous la pluie, soit au soleil ou soit sous un ciel ombrageux, à la plage rocailleuse de Quilombo, Penha, au sud du Brésil. Une heure d’éxposition à n’importe quelles conditions climatiques indiquées, n’ont pas pu altérer l’osmolalité des fluides celomiques, ce que sugère la conclusion que ces échinodermes peuvent détecter immédiatement sa exposition à l’air libre et peuvent tout de suite réduire la permeabilité osmotique de la membrane que recouvre son corps pour éviter perdre d’eau et, de la même façon, reduire l’absortion de l’eau pendant la pluie. On a observé une petite réduction de fluides celomiques pendant l’exposition a l’air, avec ocurrence de pluie.

Sign in / Sign up

Export Citation Format

Share Document