scholarly journals Imaging of Long-Distance α-Aminoisobutyric Acid Translocation Dynamics during Resource Capture by Serpula lacrymans

2008 ◽  
Vol 74 (9) ◽  
pp. 2700-2708 ◽  
Author(s):  
Monika Tlalka ◽  
Mark Fricker ◽  
Sarah Watkinson
Keyword(s):  
Amino Acid ◽  
Nutrient Dynamics ◽  
Photon Counting ◽  
Brown Rot ◽  
Experimental Period ◽  
Long Distance ◽  
Aminoisobutyric Acid ◽  
Wood Resource ◽  
High Concentrations ◽  
Serpula Lacrymans

ABSTRACT α-Aminoisobutyric acid (AIB) is a nonmetabolized amino acid analogue of alanine, which at low (μM) concentrations acts as a tracer for amino acid movements. At high concentrations (mM), it competitively inhibits membrane transport and metabolism of protein amino acids and acts as a systemic translocated inhibitor of mycelial extension in fungi. AIB can control mycelial spread of the basidiomycete Serpula lacrymans, the cause of brown rot of wood in buildings. However, it is not known how effectively the inhibitor is distributed throughout the mycelium. Realistically heterogeneous microcosms, in which the fungus grew across nutritionally inert sand to colonize discrete wood resources, were used to investigate patterns of inhibition and translocation following local application of AIB. At a 0.1 M concentration, locally applied AIB caused immediate arrest of extension throughout the whole mycelium, maintained for a 6-week experimental period. The dynamics of translocation of subtoxic amounts of [1-14C]AIB ([14C]AIB) were mapped by photon-counting scintillation imaging in conjunction with destructive harvest to establish the velocity, direction, and rate of translocation and the extent of [14C]AIB reallocation accompanying the invasion of fresh wood. Locally applied [14C]AIB was distributed throughout complex mycelial networks within 2 h of application, becoming localized in growing margins by 12 h. Encounter with a fresh wood resource triggered a widespread response, causing withdrawal of [14C]AIB from throughout the network, accompanied by accumulation in the newly colonized wood and associated mycelium. The results are discussed in the context of nutrient dynamics in wood decomposer fungi and the mechanism of the amino acid reallocation response.

Effect of calcium on uptake of α-aminoisobutyric acid by parathyroid glands

1963 ◽  
Vol 205 (5) ◽  
pp. 816-820 ◽  
Author(s):  
Lawrence G. Raisz ◽  
James E. O'Brien
Keyword(s):  
Amino Acid ◽  
Amino Acid Transport ◽  
Calcium Concentration ◽  
Inhibitory Effect ◽  
Magnesium Concentration ◽  
Acid Transport ◽  
Bicarbonate Buffer ◽  
Hormone Synthesis ◽  
Aminoisobutyric Acid ◽  
High Concentrations

The uptake of α-aminoisobutyric acid (AIB) has been used as a model for the study of amino acid transport in the parathyroid gland. Freshly excised, whole rat parathyroids rapidly took up AIB when incubated in Krebs bicarbonate buffer under 5% CO2, 95% O2 at 37 C, with glucose as the only nutrient. Uptake was inversely proportional to calcium concentration in the medium over the range of 0.75 to 2.25 mm/ liter. Increasing magnesium concentration enhanced AIB uptake. Although AIB uptake was decreased in the absence of phosphate there was no stimulatory effect of increasing phosphate concentration from 0.5 to 3.0 mm/liter. Strontium had an inhibitory effect on uptake but was not as effective as calcium on an equimolar basis. High concentrations of leucine and glycine caused inhibition of uptake as did acidifying the medium to pH 7.1. Growth hormone, vitamin D, parathyroid extract, and hydrocortisone were without effect. AIB uptake of thyroid, kidney, muscle, and liver were not inhibited by calcium. The hypothesis that changes in calcium concentration control parathyroid hormone synthesis by inhibition of amino acid transport at the cell membrane is presented.

scholarly journals Small All-Range Lidar for Asteroid and Comet Core Missions

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3081
Author(s):  
Xiaoli Sun ◽  
Daniel R. Cremons ◽  
Erwan Mazarico ◽  
Guangning Yang ◽  
James B. Abshire ◽  
...  
Keyword(s):  
Fiber Lasers ◽  
Dynamic Range ◽  
Photon Counting ◽  
Avalanche Photodiode ◽  
Integration Time ◽  
Sample Collection ◽  
Long Distance ◽  
Linear Mode ◽  
Internal Gain ◽  
Pseudo Noise

We report the development of a new type of space lidar specifically designed for missions to small planetary bodies for both topographic mapping and support of sample collection or landing. The instrument is designed to have a wide dynamic range with several operation modes for different mission phases. The laser transmitter consists of a fiber laser that is intensity modulated with a return-to-zero pseudo-noise (RZPN) code. The receiver detects the coded pulse-train by correlating the detected signal with the RZPN kernel. Unlike regular pseudo noise (PN) lidars, the RZPN kernel is set to zero outside laser firing windows, which removes most of the background noise over the receiver integration time. This technique enables the use of low peak-power but high pulse-rate lasers, such as fiber lasers, for long-distance ranging without aliasing. The laser power and the internal gain of the detector can both be adjusted to give a wide measurement dynamic range. The laser modulation code pattern can also be reconfigured in orbit to optimize measurements to different measurement environments. The receiver uses a multi-pixel linear mode photon-counting HgCdTe avalanche photodiode (APD) array with near quantum limited sensitivity at near to mid infrared wavelengths where many fiber lasers and diode lasers operate. The instrument is modular and versatile and can be built mostly with components developed by the optical communication industry.

Variability of apparent ileal amino acid digestibility in different pea samples for growing-finishing pigs

1999 ◽  
Vol 79 (4) ◽  
pp. 467-475 ◽  
Author(s):  
M. Z. Fan ◽  
W. C. Sauer
Keyword(s):  
Amino Acid ◽  
Crude Protein ◽  
Corn Starch ◽  
Latin Square ◽  
Experimental Period ◽  
Trypsin Inhibitor Activity ◽  
Significant Finding ◽  
Finishing Pigs ◽  
Initial Body Weight ◽  
Ileal Digestibility

Six barrows, average initial body weight 32.5 kg, fitted with a simple T-can-nula at the distal ileum, were used to investigate factors responsible for the variability of apparent ileal amino acid (AA) digestibility values among six pea samples. The barrows were fed six corn-starch-based diets, formulated to contain 16.5% crude protein (CP) (as-fed) from six different pea samples, according to a 6 × 6 Latin square design. Chromic oxide (0.3%) was used as the digestibility marker. The pigs were fed twice daily, at 0800 and 2000 h. The dietary allowance was 1600 g−1. Each experimental period lasted 7 d. Ileal digesta were collected at 2-h intervals for a total of 24 h from 0800 h on day 6 to 0800 h on day 8. With the exception of arginine, cysteine, histidine, and methionine, there were differences (P < 0.05) in the apparent ileal digestibility values of the indispensable including semi-essential (+semi-) AA among the pea samples. Of the indispensable AA (+semi-) within each pea sample, the digestibility values of arginine and lysine were relatively high, ranging from 88.3 to 91.3% and from 78.7 to 85.2%, respectively, while the digestibility values of cysteine, methionine, and tryptophan were relatively low, ranging from 53.8 to 62.7%, from 69.4 to 75.4%, and from 53.1 to 70.4%, respectively. With the exception of arginine, cysteine, and tryptophan, the ileal digestibility values of the indispensable AA (+semi-) were negatively correlated (P < 0.05) with the neu-tral-detergent fiber content in the pea samples. Of all the AA, only the digestibility of tryptophan was negatively correlated (P < 0.05) with the trypsin inhibitor activity in the pea samples. The significant finding of this study was that with the exception of arginine, cysteine, and proline, differences in the digestibility values of all other AA in the pea samples were positively correlated (P < 0.05) with their respective dietary AA contents. This suggests that differences in AA levels in the assay diets were responsible for the variability of apparent ileal digestibility values of AA between pea samples. Therefore, to eliminate this methodological effect, true rather than apparent ileal AA digestibility values for peas should be determined. Key words: Amino acids, ileal digestibility, peas, pigs

Effect of dietary fibre level on amino acid digestibility in young pigs

1994 ◽  
Vol 74 (2) ◽  
pp. 327-333 ◽  
Author(s):  
S. Li ◽  
W. C. Sauer ◽  
R. T. Hardin
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Soybean Meal ◽  
Dietary Fibre ◽  
Crude Protein ◽  
Corn Starch ◽  
Experimental Period ◽  
Period Change ◽  
Young Pigs ◽  
Average Body

Studies were carried out with 12 pigs (Yorkshire × Landrace) to determine the effect of dietary fibre level on amino acid digestibility. The pigs were weaned at 21 d of age and fitted with a simple T-cannula at the distal ileum at 23 or 24 d of age. The pigs were fed four isonitrogenous corn starch-based soybean meal diets (22.5 % crude protein) containing 4.3, 7.3, 10.3 and 13.3% Solkafloc according to a balanced two-period change-over design. The pigs were fed four times daily, equal amounts, at 6-h intervals. The diets were supplied at a rate of 5% of the average body weight which was determined at the initiation of the first (8.8 kg) and second (11.7 kg) experimental period. Each experimental period comprised 10 d. Feces were collected for 48 h on days 6 and 7 and ileal digesta for 24 h during days 8, 9 and 10. Chromic oxide was used as digestibility marker. The dietary inclusion of Solkafloc, up to 13.3 %, did not affect (P > 0.05) the apparent ileal as well as the fecal digestibilities of crude protein and amino acids. In conclusion, starter pigs can tolerate up to 13.3% Solkafloc, equivalent to 16.8% neutral-detergent fibre, in corn starch-based soybean meal diets without a depression in amino acid digestibility. Key words: Young pigs, fibre, amino acids, digestibility

Root uptake and xylem transport of cadmium in wheat and triticale as affected by exogenous amino acids

2017 ◽  
Vol 68 (5) ◽  
pp. 415 ◽  
Author(s):  
K. Khodamoradi ◽  
A. H. Khoshgoftarmanesh ◽  
S. A. M. Mirmohammady Maibody
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Bread Wheat ◽  
Nutrient Solution ◽  
Metal Ion ◽  
Xylem Sap ◽  
Root Uptake ◽  
Plant Roots ◽  
Control Treatment ◽  
Long Distance

Organic acids exuded from plant roots significantly modify uptake and long-distance translocation of metals. Little is known about the effect of amino acids on metal ion uptake by plant roots. The present study investigated the effects of exogenous amino acids (histidine and glycine) in a nutrient solution on root uptake and xylem sap transport of cadmium (Cd) in triticale (× Triticosecale cv. Elinor) and bread wheat (Triticum aestivum L. cv. Back Cross Rushan). Plant seedlings were grown in a Cd-free modified Hoagland nutrient solution to which 1 µm Cd was added with either 50 µm histidine or 50 µm glycine or without amino acids at 4 weeks after germination. A control treatment consisted of a nutrient solution free of Cd and amino acids. In bread wheat, addition of histidine to the Cd-containing nutrient solution resulted in a higher operationally defined symplastic Cd fraction but a lower apoplastic one in the roots. In triticale, addition of either amino acid decreased the symplastic Cd fraction but increased the apoplastic one. Addition of histidine to the nutrient solution increased Cd concentration in wheat xylem sap but had no significant effect on Cd concentration in triticale xylem sap. Compared with the Cd-only treatment, the glycine-containing treatment led to significantly reduced Cd concentrations in xylem sap of both plant species. Wheat plants supplied with histidine and Cd accumulated greater amounts of Cd in their shoots than those supplied with Cd alone. Glycine had no significant effects on the Cd content of wheat shoots but decreased it in triticale shoots. Results indicate that the effects of amino acids on plant root uptake and xylem sap translocation of Cd depend on the type of amino acid supplemented. This finding is of great importance for selecting and/or breeding cultivars with Cd-toxicity tolerance.

scholarly journals Particleboards from Recycled Thermally Modified Wood

Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1462
Author(s):  
Ján Iždinský ◽  
Zuzana Vidholdová ◽  
Ladislav Reinprecht
Keyword(s):  
Mechanical Properties ◽  
Urea Formaldehyde ◽  
Brown Rot ◽  
Decay Resistance ◽  
Raw Material ◽  
Modulus Of Rupture ◽  
Negative Effect ◽  
Serpula Lacrymans ◽  
Thermally Modified Wood ◽  
Modified Wood

In recent years, the production and consumption of thermally modified wood (TMW) has been increasing. Offcuts and other waste generated during TMWs processing into products, as well as already disposed products based on TMWs can be an input recycled raw material for production of particleboards (PBs). In a laboratory, 16 mm thick 3-layer PBs bonded with urea-formaldehyde (UF) resin were produced at 5.8 MPa, 240 °C and 8 s pressing factor. In PBs, the particles from fresh spruce wood and mixed particles from offcuts of pine, beech, and ash TMWs were combined in weight ratios of 100:0, 80:20, 50:50 and 0:100. Thickness swelling (TS) and water absorption (WA) of PBs decreased with increased portion of TMW particles, i.e., TS after 24 h maximally about 72.3% and WA after 24 h maximally about 64%. However, mechanical properties of PBs worsened proportionally with a higher content of recycled TMW—apparently, the modulus of rupture (MOR) up to 55.5% and internal bond (IB) up to 46.2%, while negative effect of TMW particles on the modulus of elasticity (MOE) was milder. Decay resistance of PBs to the brown-rot fungus Serpula lacrymans (Schumacher ex Fries) S.F.Gray increased if they contained TMW particles, maximally about 45%, while the mould resistance of PBs containing TMW particles improved only in the first days of test. In summary, the recycled TMW particles can improve the decay and water resistance of PBs exposed to higher humidity environment. However, worsening of their mechanical properties could appear, as well.

Stimulation of transport of alpha-aminoisobutyric acid into the testes of immature mice in vivo by follicle-stimulating hormone

1982 ◽  
Vol 100 (1) ◽  
pp. 137-142
Author(s):  
Nila Oza ◽  
Sarah J. Meanock ◽  
A. G. Davies
Keyword(s):  
Protein Synthesis ◽  
Amino Acid ◽  
Amino Acid Transport ◽  
Specific Activity ◽  
Follicle Stimulating Hormone ◽  
Acid Transport ◽  
Aminoisobutyric Acid ◽  
Old Mice ◽  
Stimulation Of

Abstract. Groups of immature mice were injected sc with radiocarbon-labelled alpha-aminoisobutyric acid (AIB) after being given a single sc injection of hFSH or of 0.9% saline. As an index of the transport of AIB, the specific activity of isotope was measured in homogenates of testis and of liver. FSH treatment caused statistically significant increases in the specific activity of isotope in the testes and in the ratio of testicular to liver specific activity. The effect was greatest in 9-day-old mice injected with FSH 16 h before removal of the testes. Uptake of labelled AIB was not stimulated after administration of hCG or testosterone. Doses of cycloheximide sufficient to reduce the rate of protein synthesis by over 99% did not impair testicular uptake of labelled AIB or the influence of FSH on AIB uptake. These results suggest that FSH stimulates amino acid transport into cells of the immature testis and that this action is independent of the stimulatory effect of FSH on testicular protein synthesis.

Active Transport of α-Aminoisobutyric Acid by the Isolated Midgut of Hyalophora Cecropia

1972 ◽  
Vol 56 (1) ◽  
pp. 167-172
Author(s):  
SIGNE NEDERGAARD
Keyword(s):  
Amino Acid ◽  
Active Transport ◽  
Opposite Direction ◽  
Amino Acid Transport ◽  
Amino Acid Uptake ◽  
Acid Uptake ◽  
Acid Transport ◽  
Active Process ◽  
Aminoisobutyric Acid ◽  
Amino Acid Flux

1. The α-aminoisobutyric acid flux from lumen to blood of the isolated Cecropia midgut is around 17 µmole/h, while the amino acid flux in the opposite direction is on average 0.3 µmole/h. 2. The amino acid uptake is inhibited by lack of oxygen. It is suggested that the amino acid transport from lumen to blood is an active process. 3. The amino acid uptake is inhibited by short-circuiting the midgut potential, indicating that there is no direct correlation between the active transport of potassium and the uptake of the amino acid by the midgut.

Intestinal fat differentially suppresses sham feeding of different gustatory stimuli

1996 ◽  
Vol 270 (5) ◽  
pp. R1122-R1125 ◽  
Author(s):  
L. A. Foster ◽  
K. Nakamura ◽  
D. Greenberg ◽  
R. Norgren
Keyword(s):  
Experimental Period ◽  
Liquid Diet ◽  
Short Term ◽  
Total Consumption ◽  
Sham Feeding ◽  
Entire Experimental Period ◽  
Intermediate Consumption ◽  
Complete Diet ◽  
Bottle Test ◽  
High Concentrations

To determine the intestinal contribution to short-term satiety for solutions of varying palatability, 10 ml of either 0.15 M NaCl or lipid (Intralipid: 0.125, 0.25, 0.5, and 1.0 kcal/ml) was infused at a rate of 0.5 ml/min into the duodenum of rats that were sham feeding either a liquid diet (0.5 kcal/ml), 0.3 M sucrose (0.4 kcal/ml), or a 0.1 M solution of glucose polymers (Polycose 0.4 kcal/ml). Differences in palatability were estimated by the total consumption of each solution over 90 min in a one-bottle test. The intake of solutions maximally ingested during the saline infusions (Polycose > Sucrose > liquid diet) was the most sensitive to the lipid infusions. All four lipid concentrations suppressed intake of Polycose, the solution consumed the most; the three highest concentrations suppressed intake of sucrose (intermediate consumption), and only the two highest concentrations suppressed intake of the complete diet, the solution consumed the least. Nevertheless, the duration of suppression was shorter for the solutions the rats drank the most. For the solution the rats drank the least (liquid diet), the two high concentrations of lipid that suppressed intake did so for the entire experimental period, whereas for Polycose, al lipid infusions suppressed intake, but it recovered to control levels for all but the highest concentration. Other studies have reported that increasing diet palatability shortens the duration of satiety. The current results suggest that this effect may reflect the duration of intake suppression elicited by nutrients in the intestine.

scholarly journals Effects of organic compounds on the macroalgae culture of Aegagropila linnaei

2015 ◽  
Vol 13 (1) ◽  
Author(s):  
Beata Messyasz ◽  
Boguslawa Leska ◽  
Joanna Fabrowska ◽  
Marta Pikosz ◽  
Adam Cieslak ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Amino Acid ◽  
Organic Compounds ◽  
Amino Acid Content ◽  
Test System ◽  
Ash Content ◽  
Biomass Composition ◽  
Amino Acids Composition ◽  
High Concentrations ◽  
The Impact

AbstractThe effects of the impact of four organic compounds (ascorbic acid, biotin, glucose and sucrose) on ash, protein, fiber, fat and amino acid contents in the freshwater Aegagropila linnaei biomass were examined in 7 and 14 days of cultivations in high concentrations of tested compounds (100 mg L-1). The presence of examined organic compounds had a negligible effect on the development of algae and their biomass composition. There were no significant differences in the amino acids composition in the biomass in the presence of organic compounds compared to the test system. However, the increase in ash content was observed irrespective of the cultivation time in the case of all used organic compounds. Only slight differences in crude fat concentration were observed in the case of 7 days cultivation with ascorbic acid, biotin and sucrose, while the highest increase of ash content was observed after 14 days of supplementation with glucose. None of the compounds affected changes in amino acid content in the Aegagropila linnaei biomass. The results suggest that an environment enriched with the test organic compounds had only minimal, or at most short-term, effects on the algal biomass composition.

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