A method for evaluating the mean residence times of metabolites in the body, systemic circulation, and the peripheral tissue not requiring separate i.v. administration of metabolite

1987 ◽  
Vol 8 (4) ◽  
pp. 395-401 ◽  
Author(s):  
Peter Veng-Pedersen ◽  
William R. Gillespie
Keyword(s):  
Systemic Circulation ◽  
The Body ◽  
Peripheral Tissue ◽  
Residence Times ◽  
The Mean ◽  
Mean Residence Times

Symbolic Equation for the Instantaneous Amount of Substance in Linear Compartmental Systems

2011 ◽  
pp. 348-379
Author(s):  
J.M. Villalba ◽  
R. Varón ◽  
E. Arribas ◽  
R. Diaz-Sierra ◽  
F. Garcia-Sevilla ◽  
...  
Keyword(s):  
Time Course ◽  
Open Systems ◽  
Residence Times ◽  
Transient Phase ◽  
State Equations ◽  
Amount Of Substance ◽  
The Mean ◽  
Symbolic Equation ◽  
Mean Residence Times ◽  
User Friendly

The symbolic time course equations corresponding to a general model of a linear compartmental system, closed or open, with or without traps and with zero input are presented in this chapter. From here, the steady state equations are obtained easily from the transient phase equations by setting the time towards infinite. Special attention is given to the open systems, for which an exhaustive kinetic analysis has been developed to obtain important properties. Besides, the results are particularized to open systems without traps. The software COEFICOM, easy to use and with a user-friendly format of the input of data and the output of results, allows the user to obtain the symbolic expressions of the coefficients involved in the general symbolic equation and all the information necessary to derive the symbolic time course equations for closed or open systems as well as for the derivation of the mean residence times.

Human selenite metabolism: a kinetic model

1989 ◽  
Vol 257 (3) ◽  
pp. R556-R567 ◽  
Author(s):  
B. H. Patterson ◽  
O. A. Levander ◽  
K. Helzlsouer ◽  
P. A. McAdam ◽  
S. A. Lewis ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
Kinetic Model ◽  
Sodium Selenite ◽  
The Body ◽  
Residence Times ◽  
Stable Isotope Tracer ◽  
Isotope Tracer ◽  
Liver And Pancreas ◽  
Mean Residence Times ◽  
Kinetics Of

A model is developed to describe the kinetics of sodium selenite metabolism in humans, based on plasma, urine, and fecal samples obtained from six subjects over a 4-wk period after a single oral 200-micrograms dose of the enriched stable isotope tracer 74Se. The model describes absorption, distributed along the gastrointestinal tract, and enterohepatic recirculation. The model includes four kinetically distinct plasma components, a subsystem consisting of the liver and pancreas, and a slowly turning-over tissue pool. For the six subjects, the ranges of mean residence times for the four plasma components are, respectively, 0.2-1.1 h, 3-8 h, 9-42 h, and 200-285 h; for the hepatopancreatic subsystem 4-41 days; and for the tissue pool 115-285 days. Approximately 84% of the administered dose was absorbed, and after 12 days approximately 65% remained in the body. The model predicts that after 90 days approximately 35% of this Se would be retained, primarily in the tissues. Separating Se metabolism into several distinct kinetic components is a first step in identifying the efficacious, nutritious, and toxic forms of the element.

scholarly journals Pharmacokinetics and tissue residue of toltrazuril in broiler chickens

2015 ◽  
Vol 4 (3) ◽  
pp. 310 ◽  
Author(s):  
Ahmed Soliman
Keyword(s):  
Broiler Chickens ◽  
Animal Health ◽  
Tissue Level ◽  
Residence Times ◽  
Once Daily ◽  
Tissue Residue ◽  
Elimination Half ◽  
The Mean ◽  
Mean Residence Times ◽  
Broiler Feed

<p>The pharmacokinetics and tissue residue of toltrazuril (Baycox<sup>®</sup>, Bayer Animal Health) were investigated in broiler chickens after repeated oral administrations of 7 mg/kg b.wt once daily for two consecutive days. Chickens were subjected to clinical diagnosis to ensure that each one is free from any Eimeria was received a standard broiler feed free from any medications. The results revealed that following repeated oral administration; toltrazuril peaked in blood with [C<sub>max</sub>] of 6.56 and 6.70 μg/ml at [T<sub>max</sub>] of 2.56 and 2.52 hours and the elimination half-life [t<sub>1/2β</sub>] of 14.92 and 16.19 hours and the mean residence times (MRT) were 21.33 and 23.14 hours after first and second doses, respectively. The tissue level concentrations were highest in the kidney and decreased in the following order: liver &gt; lung &gt; heart &gt; muscle &gt; skin and fat. No toltrazuril residues were detected in tissues and plasma after 8 days.</p>

Environmental tritium measurements and lumped parameter modelling in the Tafilalet aquifer, south-east Morocco

2007 ◽  
Vol 95 (10) ◽  
Author(s):  
S. Bouhlassa ◽  
B. Ammary ◽  
A. Elyahyaoui
Keyword(s):  
Residence Time ◽  
Subsurface Water ◽  
Residence Times ◽  
Transport Modelling ◽  
Lumped Parameter ◽  
The Mean ◽  
Mean Residence Times ◽  
Environmental Tritium ◽  
Future Work

The paper presents a case study for the application of environmental tritium to assess the mean residence time of water in the Tafilalet aquifer. This aquifer corresponds geologically to a tectonic depression with Quaternary fill. The Tafilalet area depends mainly on agriculture and herding. Groundwater is the main source of water supply for domestic, agriculture, and herding purposes.The data on the distribution of tritium in subsurface water indicate the modern water of the Tafilalet aquifer. The tritium transport modelling indicates that Quaternary alluvial waters are likely to have short mean residence times of a few years (14 to 32 years). The study addresses several difficulties concerning the detailed quantitative interpretations of the results, which must be the focus of future work.

Gut microbiome a promising target for management of respiratory diseases

2020 ◽  
Vol 477 (14) ◽  
pp. 2679-2696
Author(s):  
Riddhi Trivedi ◽  
Kalyani Barve
Keyword(s):  
Respiratory Diseases ◽  
New Technology ◽  
Bacterial Flora ◽  
Systemic Circulation ◽  
The Body ◽  
Lung Pathology ◽  
Promising Target ◽  
Current Therapies ◽  
Intestinal Microbial Flora ◽  
On Chip

The intestinal microbial flora has risen to be one of the important etiological factors in the development of diseases like colorectal cancer, obesity, diabetes, inflammatory bowel disease, anxiety and Parkinson's. The emergence of the association between bacterial flora and lungs led to the discovery of the gut–lung axis. Dysbiosis of several species of colonic bacteria such as Firmicutes and Bacteroidetes and transfer of these bacteria from gut to lungs via lymphatic and systemic circulation are associated with several respiratory diseases such as lung cancer, asthma, tuberculosis, cystic fibrosis, etc. Current therapies for dysbiosis include use of probiotics, prebiotics and synbiotics to restore the balance between various species of beneficial bacteria. Various approaches like nanotechnology and microencapsulation have been explored to increase the permeability and viability of probiotics in the body. The need of the day is comprehensive study of mechanisms behind dysbiosis, translocation of microbiota from gut to lung through various channels and new technology for evaluating treatment to correct this dysbiosis which in turn can be used to manage various respiratory diseases. Microfluidics and organ on chip model are emerging technologies that can satisfy these needs. This review gives an overview of colonic commensals in lung pathology and novel systems that help in alleviating symptoms of lung diseases. We have also hypothesized new models to help in understanding bacterial pathways involved in the gut–lung axis as well as act as a futuristic approach in finding treatment of respiratory diseases caused by dysbiosis.

Evaluation of Salivary Antioxidants and Oxidative Stress Markers in Male Smokers

2019 ◽  
Vol 22 (7) ◽  
pp. 496-501
Author(s):  
Fatemeh Ahmadi-Motamayel ◽  
Parisa Falsafi ◽  
Hamidreza Abolsamadi ◽  
Mohammad T. Goodarzi ◽  
Jalal Poorolajal
Keyword(s):  
Oxidative Stress ◽  
Uric Acid ◽  
Free Radicals ◽  
Antioxidant Capacity ◽  
Cigarette Smoke ◽  
Total Antioxidant Capacity ◽  
The Body ◽  
Total Antioxidant ◽  
The Mean ◽  
And Oxidative Stress

Background: Cigarette smoke free radicals can cause cellular damage and different diseases. All the body fluids have antioxidants which protect against free radicals. Objective: The aim of this study was to evaluate salivary total antioxidant capacity and peroxidase, uric acid and malondialdehyde levels in smokers and a nonsmoking control group. Methods: Unstimulated saliva was collected from 510 males. A total of 259 subjects were current smokers and 251 were non-smokers. The levels of salivary total antioxidant capacity, uric acid, peroxidase and malondialdehyde were measured using standard procedures. Data were analyzed with t test and ANOVA. Results: The smokers were younger and dental hygiene index was higher than healthy nonsmoking controls. The mean total antioxidant capacity in smokers and nonsmokers was 0.13±0.07 and 0.21±011, respectively (P=0.001). Smokers had significantly lower peroxidase and uric acid levels than healthy controls. In addition, the mean malondialdehyde levels in the smokers and nonsmokers were 4.55 ±2.61 and 2.79 ±2.21, respectively (P=0.001). Conclusion: Cigarette smoke produces free radical and oxidative stress, causing many side effects. Salivary antioxidant levels decreased and malondialdehyde levels increased in smokers, indicating the high oxidative stress among smokers compared to nonsmokers. Cigarette smoke had deleterious effects on main salivary antioxidants levels.

Effect of High Plane of Nutrition on Blood Biochemical Profile and Onset of Puberty in Prepubertal HF X Kankrej Crossbred Heifers

2019 ◽  
Vol 15 (02) ◽  
pp. 14-17
Author(s):  
K K Hadiya ◽  
A J Dhami ◽  
D V Chaudhari ◽  
P M Lunagariya
Keyword(s):  
Body Weight ◽  
Treatment Group ◽  
Plasma Levels ◽  
Age Of Onset ◽  
The Body ◽  
Monthly Interval ◽  
Control Group ◽  
Blood Biochemical ◽  
Lower Protein ◽  
The Mean

This study was initiated on 24 prepubertal Holstein x Kankrej crossbred heifers of nearly identical age (7-9 months) and body weight (130-140 kg) at University farm to evaluate the effect of high plane of nutrition on blood biochemical and minerals profile and the age at puberty. Twelve heifers were managed under routine farm feeding (control) and the rest 12 under ideal optimum feeding regime (treatment) that included extra 1 kg concentrate, 30 g min mix and ad-lib dry fodder. The body weight and ovarian ultrasonography together with blood sampling was carried out at monthly interval from 10 to 18 months of age to study the ovarian dynamics and blood biochemical changes. High plane of nutrition to growing heifers was beneficial in reducing the age of onset of puberty (by 2-3 months) compared to routine farm fed group. The mean plasma total protein and cholesterol concentrations showed a rising trend with significant variations from 10 to 16 months of age, where it got mostly stabilized indicating adult profile. The activity of enzymes GOT and GPT also rose gradually and significantly from 10 months till 14-15 months of age, and thereafter it remained more or less static till 18 months of age. The levels of both these enzymes were higher, with lower protein and cholesterol, in control than the treatment group from 15-16 months of age onwards. The mean plasma levels of both calcium and phosphorus increased gradually and significantly with advancing age till 16-17 months of age, with little higher values in supplemented than a control group. The plasma levels of zinc, iron, copper, and cobalt also showed rising trend with significant differences between 10th and 12th-14th months of age, and from 15th to 18th months of age the levels were statistically the same in all the groups with slightly higher values in the treatment group.

scholarly journals Comparative study between fascia lata and temporalis fascia in myringoplasty

2020 ◽  
Vol 36 (1) ◽  
Author(s):  
Ayman Ali Abdel Fattah ◽  
Abdel Hay Rashad Elasy ◽  
Ahmed Helmy Hoseini ◽  
Tarek Abdel Rahman Abdel Hafez
Keyword(s):  
Tympanic Membrane ◽  
Good Alternative ◽  
Fascia Lata ◽  
The Body ◽  
Temporalis Fascia ◽  
Fascia Graft ◽  
Fascia Lata Graft ◽  
Group A ◽  
The Mean ◽  
Group B

Abstract Background Repair of a perforated tympanic membrane (myringoplasty) can facilitate normal middle ear function, resist infection, and help re-establish normal hearing. Autogenous graft materials are the most popular graft materials used in myringoplasty because of their easy acceptability by the body. This study is conducted to compare between temporalis fascia graft and fascia lata graft in myringoplasty for patients with tubo-tympanic dry perforation. Results A total of 60 patients with persistent dry tympanic membrane perforation were included in our study during the period from January 2018 to May 2020. Patients underwent myringoplasty with temporalis fascia (30 patients as group A) or fascia lata (30 patients as group B). Patients were scheduled for follow-up visits concerning graft status, ear discharge, and audiograms. The mean postoperative air-bone gap in group A was 17.5 ± 4 after 1 month and 8.6 ± 6.9 after 3 months, while in group B, the mean postoperative air-bone gap was 17.6 ± 4.9 after 1 month and 9.4 ± 7.5 after 3 months. There was 90% success in graft uptake in group A, while there was 80% success in group B. Conclusion Using temporalis fascia is still the best and most trustworthy technique of myringoplasty compared to fascia lata graft. However, fascia lata can be a good alternative to temporalis fascia especially in cases of revision myringoplasty, ears having large perforation, or near-total perforation where the chances of residual perforation are high because of the limited margin of remnant tympanic membrane overlapping the graft.

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