Growth of embryonic softshell turtles is unaffected by uremia

1990 ◽  
Vol 68 (5) ◽  
pp. 841-844 ◽  
Author(s):  
Gary C. Packard ◽  
Mary J. Packard
Keyword(s):  
Body Fluids ◽  
Intermediary Metabolism ◽  
Injection Protocol ◽  
Softshell Turtles ◽  
Rates Of Growth ◽  
Different Levels

We injected eggs of softshell turtles (Trionyx spiniferus) with solutions of urea at the midpoint of incubation to induce different levels of uremia in developing embryos. The experiment was undertaken as a test of the hypothesis that urea inhibits intermediary metabolism of embryos and thereby causes a reduction in their rates of growth. The injection protocol elicited a physiologically realistic range of uremias, but we found no evidence that metabolism or growth of embryos was impaired even at the highest levels of uremia. The most likely explanation for our results is that the uremias commonly encountered during natural incubation by embryos of this and other species of turtle are insufficient to inhibit intermediary metabolism. Thus, the influence of the hydric environment on metabolism and growth of embryonic turtles apparently is not mediated by differential rates of increase in the concentration of urea in body fluids.

Control of metabolism and growth in embryonic turtles: a test of the urea hypothesis

1989 ◽  
Vol 147 (1) ◽  
pp. 203-216
Author(s):  
G. C. Packard ◽  
M. J. Packard
Keyword(s):  
Water Balance ◽  
Water Exchange ◽  
Present Form ◽  
Intermediary Metabolism ◽  
Chelydra Serpentina ◽  
Snapping Turtles ◽  
Injection Protocol ◽  
Induced Variation ◽  
Fluid Compartments ◽  
Different Levels

We performed two experiments to determine (1) whether the metabolism and growth of embryonic snapping turtles (Chelydra serpentina) incubating in wet and dry environments are correlated inversely with the concentration of urea inside their eggs, and (2) whether urea accumulating inside eggs might be the cause of reductions in metabolism and growth by embryos. Eggs in the first experiment were incubated in different hydric environments to induce different patterns of net water exchange between the eggs and their surroundings. Turtles hatching from eggs that were in positive water balance had larger carcasses, smaller residual yolks and lower concentrations of urea in their blood than animals emerging from eggs that were in negative water balance. Thus, we confirmed the existence of correlations among water exchange by eggs, concentrations of urea in fluid compartments inside eggs, and metabolism and growth of embryos. In the second experiment, eggs were injected with solutions of urea at the mid-point of incubation to induce different levels of uremia in developing embryos. The injection protocol induced variation in the concentration of urea in blood of hatchlings similar to that observed in the first experiment for turtles hatching in wet and dry environments. However, the injection protocol did not induce variation in size of hatchlings or in mass of their residual yolk. Thus, the reduction in metabolism and growth of chelonian embryos developing in dry environments does not result from an inhibition of intermediary metabolism caused by urea, and the ‘urea hypothesis’ for control of metabolism cannot be accepted in its present form.

scholarly journals Variations In Different Isolates Of Rhizoctonia Solani Based On Temperature And pH

1970 ◽  
Vol 36 (3) ◽  
pp. 389-396 ◽  
Author(s):  
BK Goswami ◽  
MM Rahaman ◽  
AKMA Hoque ◽  
K Bhuiyan ◽  
IH Mian
Keyword(s):  
Growth Factors ◽  
Rhizoctonia Solani ◽  
Radial Growth ◽  
Mycelial Growth ◽  
Potato Dextrose Agar ◽  
Optimum Temperature ◽  
Optimum Ph ◽  
Sclerotial Formation ◽  
Rates Of Growth ◽  
Different Levels

An experiment was conducted to find out variation in isolated Rhizoctonia solani based on radial mycelial growth and sclerotial production. Five isolates of Rhizoctonia solani representing five clusters group were selected and were grown at different levels of temperature and pH on potato dextrose agar (PDA). It was observed that optimum temperature and pH for growth and scierotial production varied among the isolates. The rates of growth and sclerotial formation were not uniform at the same levels of the two growth factors. The maximum mycelial growth of all isolates was found at 30°C. At 35°C, only GAZ-9 and GAZ-18 showed initiation of growth, but the rate was very slow. The optimum temperature for sclerotial production of the isolates GAZ-9, JES- 16, GAZ-18 SYL-26 was 30°C and for the isolate DIN-8 was 25°C. The optimum pH for maximum radial growth was 6 for DIN-8 and 7 for other four isolates. The maximum number of sclerotia was produced by DIN-8, GAZ-9, and SYL-30 at pH 8, 4, and 7, respectively. The optimum pH for sclerotia formation in JES-16 and GAZ-18 was pH 6. Keywords: Rhizoctonia solani; variations; temperature; pH. DOI: http://dx.doi.org/10.3329/bjar.v36i3.9267 BJAR 2011; 36(3): 389-396

scholarly journals Inter-relations between 3-hydroxypropionate and propionate metabolism in rat liver: relevance to disorders of propionyl-CoA metabolism

2017 ◽  
Vol 313 (4) ◽  
pp. E413-E428 ◽  
Author(s):  
Kirkland A. Wilson ◽  
Yong Han ◽  
Miaoqi Zhang ◽  
Jeremy P. Hess ◽  
Kimberly A. Chapman ◽  
...  
Keyword(s):  
Citric Acid Cycle ◽  
Adenine Nucleotides ◽  
Propionic Acidemia ◽  
Body Fluids ◽  
Intermediary Metabolism ◽  
Acid Cycle ◽  
Propionate Metabolism ◽  
Stable Isotopic ◽  
High Concentrations ◽  
Related Compounds

Propionate, 3-hydroxypropionate (3HP), methylcitrate, related compounds, and ammonium accumulate in body fluids of patients with disorders of propionyl-CoA metabolism, such as propionic acidemia. Although liver transplantation alleviates hyperammonemia, high concentrations of propionate, 3HP, and methylcitrate persist in body fluids. We hypothesized that conserved metabolic perturbations occurring in transplanted patients result from the simultaneous presence of propionate and 3HP in body fluids. We investigated the inter-relations of propionate and 3HP metabolism in perfused livers from normal rats using metabolomic and stable isotopic technologies. In the presence of propionate, 3HP, or both, we observed the following metabolic perturbations. First, the citric acid cycle (CAC) is overloaded but does not provide sufficient reducing equivalents to the respiratory chain to maintain the homeostasis of adenine nucleotides. Second, there is major CoA trapping in the propionyl-CoA pathway and a tripling of liver total CoA within 1 h. Third, liver proteolysis is stimulated. Fourth, propionate inhibits the conversion of 3HP to acetyl-CoA and its oxidation in the CAC. Fifth, some propionate and some 3HP are converted to nephrotoxic maleate by different processes. Our data have implications for the clinical management of propionic acidemia. They also emphasize the perturbations of the liver intermediary metabolism induced by supraphysiological, i.e., millimolar, concentrations of labeled propionate used to trace the intermediary metabolism, in particular, inhibition of CAC flux and major decreases in the [ATP]/[ADP] and [ATP]/[AMP] ratios.

scholarly journals Pathogenesis of the initial stages of severe COVID-19

2021 ◽  
Vol 12 (2) ◽  
pp. 83-102
Author(s):  
A S. Golota ◽  
Tatyana A. Kamilova ◽  
Olga V. Shneider ◽  
Dmitry A. Vologzhanin ◽  
Sergey G. Sherbak
Keyword(s):  
Reproductive Organs ◽  
Body Fluids ◽  
Effective Strategies ◽  
Organ Systems ◽  
Heart Blood ◽  
Viral Components ◽  
Innate Antiviral Immunity ◽  
Different Levels ◽  
Shed Light

Since SARS-CoV-2 first appeared in humans, the scientific community has tried to gather as much information as possible in order to find effective strategies for the containment and treatment this pandemic coronavirus. We reviewed the current published literature on SARS-CoV-2 with an emphasis on the distribution of SARS-CoV-2 in tissues and body fluids, as well as data on the expression of its input receptors on the cell surface. COVID-19 affects many organ systems in many ways. These varied manifestations are associated with viral tropism and immune responses of the infected person, but the exact mechanisms are not yet fully understood. We emphasize the broad organotropism of SARS-CoV-2, as many studies have identified viral components (RNA, proteins) in many organs, including immune cells, pharynx, trachea, lungs, blood, heart, blood vessels, intestines, brain, kidneys, and male reproductive organs. Viral components are present in various body fluids, such as mucus, saliva, urine, cerebrospinal fluid, semen and breast milk. The main SARS-CoV-2 receptor, ACE2, is expressed at different levels in many tissues throughout the human body, but its expression levels do not always correspond to the detection of SARS-CoV-2, indicating a complex interaction between the virus and humans. We also highlight the role of the renin-angiotensin aldosterone system and its inhibitors in the context of COVID-19. In addition, SARS-CoV-2 has various strategies that are widely used in various tissues to evade innate antiviral immunity. Targeting immune evasion mediators of the virus can block its replication in COVID-19 patients. Together, these data shed light on the current understanding of the pathogenesis of SARS-CoV-2 and lay the groundwork for better diagnosis and treatment of patients with COVID-19.

Low-anxiety rats are more sensitive to amphetamine in comparison to high-anxiety rats

2016 ◽  
Vol 31 (1) ◽  
pp. 115-126 ◽  
Author(s):  
Małgorzata H Lehner ◽  
Ewa Taracha ◽  
Ewelina Kaniuga ◽  
Aleksandra Wisłowska-Stanek ◽  
Marek Gryz ◽  
...  
Keyword(s):  
Positive Reinforcement ◽  
Preference Test ◽  
Brain Regions ◽  
High Anxiety ◽  
General Hypothesis ◽  
Emotional Processes ◽  
Cortex Area ◽  
Injection Protocol ◽  
Different Levels ◽  
Conditioned Place Preference Test

This study utilised the two injection protocol of sensitisation (TIPS) and the conditioned place preference test to validate and extend previous findings on the effects of amphetamine on positive reinforcement-related 50 kHz ultrasonic vocalisation (USV) in rats. We also examined changes in the expression of c-Fos and the NMDA receptor 2B (GluN2B) subunit, markers of neuronal activity and plasticity, in brain regions of rats in response to TIPS. We used low anxiety-responsive (LR) and high anxiety-responsive (HR) rats, which are known to exhibit different fear-conditioned response strengths, different susceptibilities to amphetamine in the TIPS procedure and different amphetamine-dependent 50 kHz USV responses. The LR rats, compared to the HR rats, not only vocalised much more intensely but also spent significantly more time in the amphetamine-paired compartment. After the second dose of amphetamine, the LR rats exhibited more c-Fos and GluN2B activation in layers II and III of the M1/M2 motor cortex area and prefrontal cortex (PRE, PRL, IL) and also presented with more GluN2B activation in the basal amygdala. These data reveal that HR and LR rats exhibit different levels of reactivity in the cortical-limbic pathway, which controls reward-related motivational processes. These findings contribute to the general hypothesis that heterogeneity in emotional processes is one of the causes of sensitisation to amphetamine and drug addiction.

scholarly journals Acid-base regulation in tadpoles of Rana catesbeiana exposed to environmental hypercapnia.

1997 ◽  
Vol 200 (19) ◽  
pp. 2507-2512 ◽  
Author(s):  
M Busk ◽  
E H Larsen ◽  
F B Jensen
Keyword(s):  
Rana Catesbeiana ◽  
Extracellular Fluid ◽  
Body Fluids ◽  
The Body ◽  
Acid Base ◽  
Regulatory Response ◽  
High Degree ◽  
Internal Buffer ◽  
Different Levels ◽  
Tail Muscle

Tadpoles of Rana catesbeiana were exposed to different levels of environmental hypercapnia. The acid-base regulatory response differed from that in adult amphibians in showing a high degree of pH compensation in the extracellular fluid (65-85%) and complete compensation in the intracellular fluid (tail muscle and liver) within 24 h. Hypercapnia induced a massive transfer of HCO3- equivalents and Ca2+ from the tadpoles to the environment, which lasted some 4-6 h. Bicarbonate accumulated in the body fluids came mainly from internal buffer sources (probably CaCO3 in lime sacs and/or skin deposits). It is suggested that the large bicarbonate efflux from the animal is a consequence of the dissolution of CaCO3 stores and the delayed adjustment of bicarbonate-retaining mechanisms. Re-exposure of tadpoles to hypercapnia after 1-3 weeks of normocapnic recovery only affected transepithelial fluxes of acid-base equivalents marginally, suggesting that mobilisable CaCO3 stores were depleted during the first exposure to hypercapnia and that they were not refilled. The CaCO3 stores may normally be mobilised during the slowly developing internal hypercapnia that occurs during metamorphosis.

Dependence of Intergranular Fracture on Boundary Topography and Cohesion

1973 ◽  
Vol 31 ◽  
pp. 150-151
Author(s):  
J. E. Doherty ◽  
A. F. Giamei ◽  
B. H. Kear ◽  
C. W. Steinke
Keyword(s):  
Grain Boundary ◽  
Room Temperature ◽  
Nickel Base Superalloy ◽  
Boundary Shear ◽  
Room Temperature Ductility ◽  
Solid Solution Matrix ◽  
Nickel Base ◽  
Solution Matrix ◽  
Different Levels ◽  
Base Superalloy

Recently we have been investigating a class of nickel-base superalloys which possess substantial room temperature ductility. This improvement in ductility is directly related to improvements in grain boundary strength due to increased boundary cohesion through control of detrimental impurities and improved boundary shear strength by controlled grain boundary micros true tures.For these investigations an experimental nickel-base superalloy was doped with different levels of sulphur impurity. The micros tructure after a heat treatment of 1360°C for 2 hr, 1200°C for 16 hr consists of coherent precipitates of γ’ Ni3(Al,X) in a nickel solid solution matrix.

Immunoenzymatic demonstration of the simultaneous presence of transferrin, hemopexin and albumin in a same hepatocyte and their ultrastructural localization

1978 ◽  
Vol 36 (2) ◽  
pp. 88-89
Author(s):  
M. Kraemer ◽  
J. Foucrier ◽  
J. Vassy ◽  
M.T. Chalumeau
Keyword(s):  
Plasma Proteins ◽  
Rat Hepatocytes ◽  
Ultrastructural Localization ◽  
Carrier Proteins ◽  
Normal Cells ◽  
Adult Rat ◽  
Adult Rat Hepatocytes ◽  
Monospecific Antisera ◽  
Different Levels

Some authors using immunofluorescent techniques had already suggested that some hepatocytes are able to synthetize several plasma proteins. In vitro studies on normal cells or on cells issued of murine hepatomas raise the same conclusion. These works could be indications of an hepatocyte functionnal non-specialization, meanwhile the authors never give direct topographic proofs suitable with this hypothesis.The use of immunoenzymatic techniques after obtention of monospecific antisera had seemed to us useful to bring forward a better knowledge of this problem. We have studied three carrier proteins (transferrin = Tf, hemopexin = Hx, albumin = Alb) operating at different levels in iron metabolism by demonstrating and localizing the adult rat hepatocytes involved in their synthesis.Immunological, histological and ultrastructural methods have been described in a previous work.

Isolation of Asbestos from Lung Tissue and Sputum

1982 ◽  
Vol 40 ◽  
pp. 330-331
Author(s):  
M. G. Williams ◽  
C. Corn ◽  
R. F. Dodson ◽  
G. A. Hurst
Keyword(s):  
Sodium Hypochlorite ◽  
Lung Tissue ◽  
Body Fluids ◽  
Unknown Etiology ◽  
The Past

During this century, interest in the particulate content of the organs and body fluids of those individuals affected by pneumoconiosis, cancer, or other diseases of unknown etiology developed and concern was further prompted with the increasing realization that various foreign particles were associated with or caused disease. Concurrently particularly in the past two decades, a number of methods were devised for isolating particulates from tissue. These methods were recently reviewed by Vallyathan et al. who concluded sodium hypochlorite digestion was both simple and superior to other digestion procedures.

Electron microscopic radioautographic studies on the incorporation of 3H proline in the glomerular basement membrane (GBM) in antistreptococcal-cell-membrane (SCM) injected mice

1984 ◽  
Vol 42 ◽  
pp. 188-189
Author(s):  
R.P. Nayyar ◽  
C.F. Lange ◽  
J. L. Borke
Keyword(s):  
Body Weight ◽  
Cell Membrane ◽  
Basement Membrane ◽  
Glomerular Basement Membrane ◽  
Mesangial Matrix ◽  
Electron Microscopic ◽  
Group A ◽  
Injection Protocol

Streptococcal cell membrane (SCM) antiserum injected mice show a significant thickening of glomerular basement membrane (GBM) and an increase in mesangial matrix within 4 to 24 hours of antiserum administration (1,2,3). This study was undertaken to evaluate the incorporation of 3H proline into glomerular cells and GBM under normal and anti-SCM induced conditions. Mice were administered, intraperitoneally, 0.1 ml of normal or anti-SCM serum followed by a 10 µC/g body weight injection of 3H proline. Details of the preparation of anti-SCM (Group A type 12 streptococcal pyogenes) and other sera and injection protocol have been described elsewhere (2). After 15 minutes of isotope injection a chase of cold proline was given and animal sacrificed at 20 minutes, 1,2,4,8,24 and 48 hours. One of the removed kidneys was processed for immunofluorescence, light and electron microscopic radioautographic studies; second kidney was used for GBM isolation and aminoacid analysis.

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