scholarly journals A study of whole-body isotope dilution of [14C]ascorbic acid in guinea-pigs with graded ascorbate intakes

1992 ◽  
Vol 68 (3) ◽  
pp. 717-728 ◽  
Author(s):  
C. J. Bates ◽  
Harumi Tsuchiya ◽  
P. H. Evans
Keyword(s):  
Dietary Intake ◽  
Guinea Pigs ◽  
Specific Activity ◽  
The Body ◽  
Whole Body ◽  
Dietary Intakes ◽  
Radioactive Label ◽  
Wide Range ◽  
Specific Activities ◽  
The Individual

The purpose of the present study was first to assess the extent to which unlabelled ascorbate in the diet of guinea-pigs can exchange with labelled ascorbate within their organs when the dietary intake is varied over a wide range, and second to determine whether the retention of label might be used to assess either the amount of ascorbate intake or its biological availability where these are not known. The retention of [14C]ascorbate in the body and in various organs of guinea-pigs were, therefore, measured following a 13 d period of graded dietary intakes of ascorbate. It was found first, that the amount of label retained in each of the organs, 13 d after the initial dose of labelled ascorbate, was much more closely related to the amount of ascorbate intake after labelling than to the intake (and tissue ascorbate levels) before and at the time of labelling. Second, most of the individual internal organs exhibited a constant relationship between the specific activity at 13 d and the dietary intake, except for brain which was flushed to a smaller extent. Third, in agreement with several previous studies a high proportion of the radioactive label in the tissues was found to be still present in ascorbate. The specific activity of column-purified ascorbate was very similar to the estimated specific activity in the crude extract, which implies that it may be possible to estimate specific activities (or stable isotope enrichments) at certain sites without rigorous isolation procedures. Fourth, the amount of radioactivity appearing in the urine 2 d before killing the animals was correlated with the amount of ascorbate intake and with tissue specific activities, suggesting that intakes (or bioavailability) might be predicted from the patterns of label-appearance in the urine

Fermentative extraction of Amylase using waste Biomaterials as Substrate

2021 ◽  
pp. 4580-4582
Author(s):  
Sharmila S. ◽  
Preetha S. ◽  
Kowsalya E. ◽  
Kamalambigeswari R. ◽  
L. Jeyanthi Rebecca
Keyword(s):  
Specific Activity ◽  
Raw Materials ◽  
Maximum Activity ◽  
The Body ◽  
Biological Molecules ◽  
Treated Sample ◽  
Wide Range ◽  
Speed Up ◽  
Crude Sample ◽  
Groundnut Shell

Enzymes are biological molecules that significantly speed up the rate of virtually all of the chemical reactions that takes place within the cells. They are vital for life and serve as a wide range of important functions in the body. Solid state fermentation holds a high potential for the production of enzyme amylase using Aspergillus niger. In this work, different solid substrates such as groundnut shells, coconut coir and Palmyra sprout peels were used for the production of amylase as they are very cheap and also easily available raw materials. Then the maximum enzyme activities were analysed. Results showed that the enzyme activity of for which palmyra sprout peel was used as substrate had maximum activity in both crude sample (0.63µmol/ml.min) and in partially purified sample (1.42µmol/ml.min) and activity was found to be less for groundnut shell as substrate (crude sample 0.36µmol/ml.min) and in (treated sample 0.26µmol/ml.min) and also the specific activity was found to be maximum in palmyra sprout peel (29.2U/mg of protein) and less in groundnut shell (8.6U/mg of protein).

Unequal Absorption of Radiolabeled and Nonradiolabeled Drug from the Oral Dose Leads to Incorrect Estimates of Drug Absorption and Circulating Metabolites in a Mass Balance Study

2019 ◽  
Vol 13 (1) ◽  
pp. 37-44
Author(s):  
Ryan H. Takahashi ◽  
Jae H. Chang ◽  
Jodie Pang ◽  
Xiaorong Liang ◽  
Shuguang Ma
Keyword(s):  
Oral Dose ◽  
Mass Balance ◽  
Specific Activity ◽  
The Body ◽  
Total Drug ◽  
Beagle Dogs ◽  
Balance Study ◽  
Drug Concentrations ◽  
Specific Activities ◽  
Mass Balance Study

Background: Mass balance studies conducted using radiolabeled material (14C or 3H) definitively characterize the Absorption, Metabolism, and Excretion (AME) of a drug. A critical aspect of these studies is that the radiotracer maintains its proportion to total drug from its administration to its complete elimination from the body. In the study of GDC-0276 in beagle dogs, we observed that the 14C radiotracer proportion (specific activity) varied through the study. Method: High resolution-accurate mass spectrometric measurements of 12C and 14C isotopes of GDC- 0276 and its metabolites in plasma and excreta samples were used to determine the apparent specific activities, which were higher than the specific activity of the dosing formulation. Drug concentrations were adjusted to the observed specific activities to correct the readouts for GDC-0276 AME and PK. Results: The enrichment of 14C, which resulted in higher specific activities, was consistent with faster and more extensive absorption of the radiotracer from the dosing formulation. This resulted in overestimating the dose absorbed, the extent of elimination in urine and bile, and the exposures to circulating metabolites. These biases were corrected by the specific activities determined for study samples by mass spectrometry. Conclusion: Assuming that the radiotracer was proportional to total drug throughout a radiolabeled study was not valid in a 14C study in beagle dogs. This presumably resulted from unequal absorption of the radiotracer and nonradiolabeled test articles from the oral dose due to inequivalent solid forms. We were able to provide a more accurate description of the AME of GDC-0276 in dogs by characterizing the differential absorption of the radiotracer.

scholarly journals THE RESPONSE OF EOSINOPHILS IN THE GUINEA PIG TO SENSITIZATION, ANAPHYLAXIS AND VARIOUS DRUGS

Blood ◽  
1949 ◽  
Vol 4 (3) ◽  
pp. 217-246 ◽  
Author(s):  
MAX SAMTER
Keyword(s):  
Bone Marrow ◽  
Guinea Pig ◽  
Eosinophil Count ◽  
Guinea Pigs ◽  
Specific Antigen ◽  
Wide Range ◽  
The Individual ◽  
Bone Marrow Blood ◽  
Antihistamine Drugs ◽  
Definite Correlation

Abstract 1. The eosinophilic response of the guinea pig sensitized and reinjected with the specific antigen varies with the nature of the antigen used, but also with the individual guinea pig in any groupsensitized and reinjected with the same antigen. 2. Certain antihistamine drugs which abolish anaphylactic symptoms, do not abolish the eosinophilic response. 3. The severity of anaphylactic "shock" symptoms has no influence on the eosinophilic response. 4. Histamine phosphate has no effect on the eosinophil count of nonsensitized guinea pigs protected by benadryl; it causes a distinct eosinophilic response in sensitized animals. 5. Heparin—in the dose injected—produced only an insignificant rise in the peripheral eosinophil count of sensitized guinea pigs; adenosine had no effect. 6. Attempts were made to correlate the eosinophilic response in bone marrow, blood and shock tissue of guinea pigs sensitized and reinjected with a specific antigen. The variation within a wide range of the number of eosinophils in the bone marrow of nonsensitized and of sensitized, reinjected guinea pigs is emphasized. A definite correlation seems to exist between the presence of a large number of eosinophils in blood and lungs; it is shown, however, that this observation permits only limited conclusions. 7. The factors which account for discrepancies in the interpretation of the eosinophilic response, e.g., nature of antigen, route of administration and characteristics of species, are analyzed. 8. The significance of the findings is reviewed in the light of previous work.

Hierarchical Engineering Model of the Human Body

2016 ◽  
Author(s):  
Somayajulu D. Karamchetty
Keyword(s):  
Human Body ◽  
Hierarchical Modeling ◽  
Control Volume ◽  
The Body ◽  
Whole Body ◽  
Operational Parameters ◽  
Sufficient Detail ◽  
Wide Range ◽  
Level Model ◽  
Complex Engineering

Engineers and scientists are able to understand and analyze the behavior of complex engineering systems in a wide range of critical technologies through hierarchical modeling followed by simulation of the model operation. This process results in a high fidelity integrated model as each level in the hierarchy is modeled in sufficient detail. The overall objective of this effort is to develop a sophisticated hierarchical model of the human body, followed by simulation of the model operation. In this initial research phase, the feasibility of the concept is explored and a framework for the model is described. A six-level model consisting of the whole body as a system, system of systems, organs, tissues, cells, and molecules is proposed and described. This paper explains that the human body is amenable to such hierarchical modeling and describes the benefits that can be achieved. The systems in the body deal with numerous processes: electrical, chemical, biochemical, energy conversion, transportation, pumping, sensing, communications, and so on. Control volume models for the organs in the body capture the mass and energy balance and chemical reactions. Tissue can be represented similar to structural components made of various biomaterials. Cells can be represented as a manufacturing and maintenance workforce assisted by molecular reactions. Following the representation of a healthy body, simulation runs by inserting faults and/or deficiencies in the operational parameters into the model could reveal the causes for specific diseases and illnesses. Such modeling and simulation will benefit medical, pharmaceutical, nutritional specialists, and engineers in designing, developing, and delivering products and services to enable humans to lead healthy lives.

scholarly journals Gestational diabetes status and dietary intake modify maternal and cord blood allostatic load markers

2020 ◽  
Vol 8 (1) ◽  
pp. e001468
Author(s):  
Chauntelle Jack-Roberts ◽  
Patricia Maples ◽  
Betul Kalkan ◽  
Kaydine Edwards ◽  
Ella Gilboa ◽  
...  
Keyword(s):  
Gestational Diabetes ◽  
Dietary Intake ◽  
Allostatic Load ◽  
Glycemic Load ◽  
The Body ◽  
Future Research ◽  
P Value ◽  
Dietary Intakes ◽  
Blood Samples ◽  
Diabetes Status

IntroductionAllostatic load (AL) defines cardiometabolic, inflammatory, and neuroendocrine changes in the body in response to internal and external stressors. It is largely unknown whether gestational diabetes mellitus (GDM) alters maternal and fetal AL, which in turn affects GDM outcomes. Whether dietary intakes and quality can modify AL and thus influence GDM progression is also unknown.Research design and methodsIn this study, we recruited 35 GDM and 30 non-GDM women in gestational week 25–33. Fasting blood samples were collected at enrollment, and cord venous blood samples were collected at delivery for the measurement of a series of AL biomarkers to calculate the composite AL index. Three-day dietary recalls were conducted at enrollment.ResultsResults suggest that GDM women had 60% higher composite AL index scores (p value=0.01). Maternal AL index was associated with shorter duration of gestation (β=−0.33, p value=0.047) and higher fetal AL index (β=0.47, p value=0.006) after adjusting for GDM status. Dietary intake of monounsaturated fatty acids was negatively associated with maternal AL index (β=−0.20, p value=0.006). GDM women had lower total caloric intake and dietary glycemic load, yet their linolenic acid, vitamin C and E intakes were also decreased (all p value<0.05). These dietary differences were not related to birth outcomes measured.ConclusionsIn this study, GDM status and dietary intakes modify AL in this population. AL may serve as an indicator of GDM control. Future research on dietary interventions that can improve maternal AL markers during GDM is warranted.

Effects of Aluminum on the Leopard Frog, Rana pipiens: Life Stag Comparisons and Aluminum Uptake

1990 ◽  
Vol 47 (1) ◽  
pp. 210-216 ◽  
Author(s):  
Joseph Freda ◽  
D. Gordon McDonald
Keyword(s):  
Rana Pipiens ◽  
Low Ph ◽  
The Body ◽  
Leopard Frog ◽  
Whole Body ◽  
Toxicity Tests ◽  
Al Content ◽  
Wide Range ◽  
Water Ph ◽  
Percent Mortality

In this study, we conducted a series of toxicity tests investigating the response of embryos, prestage 25 tadpoles and 3-wk old tadpoles of the leopard frog (Rana pipiens) to a wide range pf pH (4.2–4.8) and Al (0–1000 μg∙:L−1}, and to pH 6.5 with no Al present. In embryos and prestage 25 tadpoles, Al ameliorated the toxic effects of very low pH's (4.2–4.4), while becoming toxic at higher pH's (4.6–4.8). Although both embryos and prestage 25 tadpoles were killed by low pH (pH 4.2–4.4 and 4.2, respectively) and elevated Al ([Formula: see text] and [Formula: see text] Al, respectively), embryos were relatively more sensitive (i.e. higher percent mortality) to low pH, whereas prestage 25 tadpoles were relatively more sensitive to Al Three week old tadpoles did not die at any test pH (without Al) and mortality (>20%) caused by Al occurred at only pH 4.8 and 750–1000 μg∙L−1 Al. The body sodium concentrations of 3-wk old tadpoles that survived high Al exposure were depressed indicating sublethal stress. Whole body Al uptake in 3-wk old tadpoles was also elevated in water containing high concentrations of Al, but it was positively related to water pH and exposure time. This result suggests that body Al content is not an accurate indicator of Al exposure in tadpoles living in acidic, Al contaminated ponds.

scholarly journals Exploring Experience as a Myriad Richness: Micro-phenomenology as a Transformative Approach to Research

2020 ◽  
Vol 14 (14) ◽  
pp. 13-25
Author(s):  
Magali Ollagnier-Beldame
Keyword(s):  
Subjective Experience ◽  
Ways Of Knowing ◽  
The Body ◽  
Whole Body ◽  
First Person ◽  
Knowledge Processes ◽  
Felt Sense ◽  
Transformative Approach ◽  
The Individual ◽  
Suspension Of Judgement

Over the last twenty years, researches within cognitive sciences has massively grown in the field of the ways of knowing. For instance, in recent years, the paradigm of 4-E cognition suggests that cognition involves the whole body, as well as the situation of the body in the environment. This article argues that a first-person approach enriches the understanding of the ways of knowing in their complexity - particularly by seeking to re-question classical dichotomies - through the re-integration of subjective experience. In the heart of first-person epistemology, the micro-phenomenological interview - based on the explicitation interview - consists in “guided retrospective introspections”, and allows to scientifically access subjective experience. This technique relies on the epoché – the suspension of judgement – a process at first investigated by philosophers that was made accessible to psychology to empirically investigate and study subjective experience. How does the epoché happen? What concrete acts make it up? More broadly, what is the relationship between the epoché and embodiment? This paper sheds lights on possible relations between researches describing concrete practices of the Husserlian epoché and Gendlin’s work concerning the process of Focusing, which aims at accessing the inner felt sense of experience. The process of Focusing, is a way of paying attention to one’s being-in-the-world, one’s interaction as it is experienced through the individual (but not separate) body. We will especially consider the process of “clearing a space” that Gendlin describes, as well as the rupture that occurs during the “bodily felt shift” which can be compared to the conversion happening within the process of epoché. Finally, we discuss how our proposition can allow the construction of new models of knowledge processes, the challenge of such a proposal being not only epistemological, but also ethical and societal. KEYWORDS Subjective experience, embodiment, micro-phenomenology, epoché, focusing.

scholarly journals Sociality and Interaction Envelope Organize Visual Action Representations

2019 ◽  
Author(s):  
Leyla Tarhan ◽  
Talia Konkle
Keyword(s):  
Visual Cortex ◽  
Large Scale ◽  
Functional Neuroimaging ◽  
Action Observation ◽  
The Body ◽  
Whole Body ◽  
Action Perception ◽  
Social Content ◽  
Wide Range ◽  
The Brain

Humans observe a wide range of actions in their surroundings. How is the visual cortex organized to process this diverse input? Using functional neuroimaging, we measured brain responses while participants viewed short videos of everyday actions, then probed the structure in these responses using voxel-wise encoding modeling. Responses were well fit by feature spaces that capture the body parts involved in an action and the action’s targets (i.e. whether the action was directed at an object, another person, the actor, and space). Clustering analyses revealed five large-scale networks that summarized the voxel tuning: one related to social aspects of an action, and four related to the scale of the interaction envelope, ranging from fine-scale manipulations directed at objects, to large-scale whole-body movements directed at distant locations. We propose that these networks reveal the major representational joints in how actions are processed by visual regions of the brain.Significance StatementHow does the brain perceive other people’s actions? Prior work has established that much of the visual cortex is active when observing others’ actions. However, this activity reflects a wide range of processes, from identifying a movement’s direction to recognizing its social content. We investigated how these diverse processes are organized within the visual cortex. We found that five networks respond during action observation: one that is involved in processing actions’ social content, and four that are involved in processing agent-object interactions and the scale of the effect that these actions have on the world (its “interaction envelope”). Based on these findings, we propose that sociality and interaction envelope size are two of the major features that organize action perception in the visual cortex.

scholarly journals Food Consumption in Ferzan Ozpetek’s Hamam and Luca Guadagnino’s Io sono l’amore: A Gender Issue

2018 ◽  
Vol 37 (2) ◽  
pp. 173-190
Author(s):  
Patrizia Sambuco
Keyword(s):  
Food Consumption ◽  
The Body ◽  
Sensory Level ◽  
Cultural Meanings ◽  
Self Identity ◽  
Social Conventions ◽  
Female Protagonists ◽  
Wide Range ◽  
Gender Constructions ◽  
The Individual

Within the wide range of scholarly works on food studies, the topic of food and cinema has gained increasing attention in recent years. This article contributes to the discussion offering a gender per­spective in the analysis of Italian films. It examines cinematic represen­tations of food consumption in Ferzan Ozpetek’s Hamam and Luca Guadagnino’s Io sono l’amore. Food consumption is a means of look­ing at self-identity and the relationship of the individual to the outside world. Eating implies taking part of the outside world inside, and as such it involves not only nutrition for the body but invests the sub­ject with cultural meanings. As a result, the analysis of food consump­tion lends itself to an examination of cultural gender dynamics that influence representations. Through a gender reading of specific scenes, the article argues that in spite of the apparent representations of inde­pendent, successful female protagonists who dare to challenge social conventions, the films considered contribute to the reinforcement of traditional gender constructions. Claude Fischler’s and Pasi Falk’s theo­ries of food consumption help to uncover how the sensory and aesthetic dimensions prevail in the representations of the women protagonists of the films analysed. The female protagonists’ relationship to the outside world remains an individual one, experienced at the sensory level, that cannot express the radical and collective transformations available to the male protagonists.

A minimal model for human whole body cholesterol metabolism

1993 ◽  
Vol 265 (3) ◽  
pp. E513-E520
Author(s):  
R. E. Ostlund
Keyword(s):  
Minimal Model ◽  
Cholesterol Metabolism ◽  
Specific Activity ◽  
Clinical Investigation ◽  
Plasma Cholesterol ◽  
Fractional Excretion ◽  
Compartment Model ◽  
The Body ◽  
Whole Body ◽  
Mean Values

Important work by others has shown that human whole body cholesterol metabolism can be described by a three-compartment model computed from plasma cholesterol specific activity after an intravenous infusion of labeled cholesterol. However, some parameters of that model cannot be estimated precisely [coefficient of variation (CV) 15-19% after 40 wk of follow-up], making its use in routine clinical investigation difficult. On the other hand, a simpler two-compartment model can be calculated with excellent precision from only 10 wk of data (CV 2-8%), but its parameters are inaccurate (for example, the size of the central pool is overestimated by 20%, and the rate constant for fractional excretion of cholesterol from the body is underestimated by 15%). Thus both three-compartment and two-compartment models of cholesterol turnover have important limitations. An alternative is provided by a minimal model that takes advantage of the increased precision expected in the solution of models with fewer parameters. A three-compartment structure is used, but only four (rather than 6 or more) parameters are calculated: the mass of the rapidly mixing central cholesterol compartment, the fractional rate of cholesterol elimination from the body, and the average forward and reverse rate constants for cholesterol transfer between the rapid compartment and both slower compartments. Each of these parameters can be determined unambiguously (without the need to use a minimum or maximum estimate), accurately (mean values within 2% of theory), and with precision (CV 3-13%).(ABSTRACT TRUNCATED AT 250 WORDS)

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