scholarly journals Microplastics as Vectors of Chromium and Lead during Dynamic Simulation of the Human Gastrointestinal Tract

2020 ◽  
Vol 12 (11) ◽  
pp. 4792
Author(s):  
Verónica Godoy ◽  
Antonio Martínez-Férez ◽  
María Ángeles Martín-Lara ◽  
José Antonio Vellido-Pérez ◽  
Mónica Calero ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Gastrointestinal Tract ◽  
Human Body ◽  
Surface Porosity ◽  
Human Gastrointestinal Tract ◽  
Future Studies ◽  
Other Substances ◽  
First Time ◽  
Kinetics Of

The human body is exposed to the ingestion of microplastics that are often contaminated with other substances, which can be released into our body. In this work, a dynamic in-vitro simulator of the gastrointestinal tract based on a membrane reactor has been used for the first time to study the release, bioaccessibility, and bioavailability of chromium (Cr) and lead (Pb) from polyethylene and polypropylene microplastics previously contaminated in the laboratory. The results showed that 23.11% of the initial Cr and 23.17% of the initial Pb present in microplastics were able to cross the tubular membrane, simulating the intestinal absorption phase. The pH evolution during the gastric phase and the duodenal phase, the interaction mechanisms with physiological fluids, and the properties of the polymers, such as specific surface, porosity, and/or surface degradation, affected the kinetics of release from the microplastics and the behavior of both heavy metals. Cr was released very early in the gastric phase, but also began simultaneously to precipitate quite fast, while Pb was released slower and in less quantity than Cr, and did not precipitate until the beginning of the duodenal phase. This study shows, for the first time, how useful the dynamic gastrointestinal simulator is to study the behavior of microplastics and some problematic heavy metals along the human gastrointestinal tract, and can serve as a reference for future studies focused on the effects of these substances in the human body.

scholarly journals IMMUNE RESPONSES IN VITRO

1971 ◽  
Vol 134 (2) ◽  
pp. 395-416 ◽  
Author(s):  
Carl W. Pierce ◽  
Barbara M. Johnson ◽  
Harriet E. Gershon ◽  
Richard Asofsky
Keyword(s):  
Culture Conditions ◽  
Antibody Concentration ◽  
Spleen Cells ◽  
Immunoglobulin Class ◽  
Cell Densities ◽  
Erythrocyte Antigen ◽  
First Time ◽  
Kinetics Of

We have demonstrated for the first time that mouse spleen cells stimulated in vitro with heterologous erythrocytes developed immunoglobulin class-specific γM, γ1, γ2a+2b, and γA plaque-forming cell (PFC) responses. A modification of the hemolytic plaque technique, the addition of goat anti-mouse µ-chain antibody to the assay preparation, specifically prevented development of all γM PFC and enabled accurate and reproducible enumeration of immunoglobulin class-specific PFC after treatment with appropriate monospecific anti-globulins and complement. Culture conditions, with regard to medium, atmosphere, agitation, and spleen cell densities, were similar to those previously shown to support only γM PFC responses. Evaluation of the kinetics of appearance of PFC showed that γM PFC reached maximum numbers on days 4–5; the magnitude of this response was 3–10 times greater than γ1 γ2a+2b, or γA PFC which reached maximum numbers on days 5–6. Optimal erythrocyte antigen dose for γM PFC responses was 107/culture, whereas a dose of 106 erythrocytes/culture consistently stimulated optimal γ1 γ2a+2b, or γA PFC responses. Investigations of the effects of anti-erythrocyte antibody on γM and γG PFC responses indicated that antibody suppressed these responses by neutralizing the effective antigenic stimulus at the macrophage-dependent phase of the response. At the same antibody concentration, γG PFC responses were more effectively suppressed than γM PFC responses. Further, γG responses could be almost completely suppressed by antibody as long as 48 hr after initiation of cultures, whereas γM PFC responses could only be completely suppressed during the first 24 hr. These results were discusssed in terms of the role of antigen in the stimulation γM and γG antibody.

Comparative in vitro fermentation activity in the canine distal gastrointestinal tract and fermentation kinetics of fiber sources

2008 ◽  
Vol 86 (11) ◽  
pp. 2979-2989 ◽  
Author(s):  
G. Bosch ◽  
W. F. Pellikaan ◽  
P. G. P. Rutten ◽  
A. F. B. van der Poel ◽  
M. W. A. Verstegen ◽  
...  
Keyword(s):  
Gastrointestinal Tract ◽  
In Vitro Fermentation ◽  
Fermentation Kinetics ◽  
Kinetics Of

scholarly journals Antiplasmodial Activity of Gnetum gnemon Leaves and Compounds Isolated from them

2018 ◽  
Vol 13 (10) ◽  
pp. 1934578X1801301
Author(s):  
Partha P Dutta ◽  
Manobjyoti Bordoloi ◽  
Sonali Roy ◽  
Bardwi Narzary ◽  
Kabita Gogoi ◽  
...  
Keyword(s):  
Ethanol Extract ◽  
Antiplasmodial Activity ◽  
Future Studies ◽  
North East India ◽  
North East ◽  
Gnetum Gnemon ◽  
Preliminary Study ◽  
Low Cytotoxicity ◽  
First Time

Gnetum gnemon L. (Gnetaceae) is used traditionally for treating malaria related fever by indigenous people of North East India. In our preliminary study, the ethanol extract of G. gnemon leaves showed promising antiplamodial activity against Plasmodium falciparum chloroquine sensitive (3D7) strain in vitro with an IC50 value of 29.4 μg/mL. Therefore, it was further investigated, and by following a bioassay guided approach, 2,3-dihydroxypropyl icosanoate (1), oleic acid (2) and ursolic acid (3) were isolated for the first time from this plant. Compound 3 showed highest antiplasmodial activity with IC50 values of 4.0 and 6.0 μg/mL against chloroquine sensitive (3D7) and resistant (Dd2) strains of P. falciparum, respectively. The antiplasmodial activity of 1 (IC50 9.5 and 11.4 μg/mL) and 2 (IC50 17.6 and 21.1 μg/mL) was moderate. The isolated constituents showed low cytotoxicity against rat skeletal muscle (L6) and human cervical cancer (HeLa) cells. This is the first report on the antimalarial potential of G. gnemon and the isolated compounds may be responsible for its activity. The findings of the study are in line with the ethnopharmacological claim and can be possible leads for future studies.

In vitro Gastrointestinal Models for Prebiotic Carbohydrates: A Critical Review

2019 ◽  
Vol 25 (32) ◽  
pp. 3478-3483 ◽  
Author(s):  
Oswaldo Hernandez-Hernandez
Keyword(s):  
Small Intestine ◽  
Gastrointestinal Tract ◽  
Brush Border ◽  
Critical Review ◽  
In Vitro Digestibility ◽  
Human Gastrointestinal Tract ◽  
Intestinal Brush Border ◽  
Small Intestinal ◽  
Existing Data

Background: In the last decade, various consortia and companies have created standardized digestion protocols and gastrointestinal simulators, such as the protocol proposed by the INFOGEST Consortium, the simulator SHIME, the simulator simgi®, the TIM, etc. Most of them claim to simulate the entire human gastrointestinal tract. However, few results have been reported on the use of these systems with potential prebiotic carbohydrates. Methods: This critical review addresses the existing data on the analysis of prebiotic carbohydrates by different in vitro gastrointestinal simulators, the lack of parameters that could affect the results, and recommendations for their enhancement. Results: According to the reviewed data, there is a lack of a realistic approximation of the small intestinal conditions, mainly because of the absence of hydrolytic conditions, such as the presence of small intestinal brush border carbohydrases that can affect the digestibility of different carbohydrates, including prebiotics. Conclusion: There is a necessity to standardize and enhance the small intestine simulators to study the in vitro digestibility of carbohydrates.

scholarly journals Antioxidant Activity of Medicinal Plants from Habitats with Different Anthropogenic Loads

2020 ◽  
Vol 6 (2) ◽  
pp. 119-127
Author(s):  
S.A. Kurbatov ◽  
◽  
V.M. Zubkova ◽  
Keyword(s):  
Antioxidant Activity ◽  
Free Radicals ◽  
Medicinal Plants ◽  
Human Body ◽  
Raw Materials ◽  
Mechanism Of Formation ◽  
Analysis Of Results ◽  
Biochemical Research ◽  
First Time

the analysis of results of biochemical research concerning antioxidant activity of medicinal raw materials, with use of a method of inhibition of autooxidation of adrenaline in vitro is carried out. The mechanism of formation of free radicals and their sources is considered. A brief overview of the action of free radicals on the human body and cells is given. For the first time, depending on the biological characteristics, the antioxidant activity of plants in areas characterized by different anthropogenic loads was studied: an increase in the anthropogenic load was accompanied by a decrease in the antioxidant activity of plants.

scholarly journals Heavy Metals Mixture Phytotoxic Impact upon Elodea canadensis Macrophite uner the Experimental Ecosystems Conditions

2017 ◽  
Author(s):  
Keyword(s):  
Heavy Metals ◽  
Machine Building ◽  
Elodea Canadensis ◽  
Polluted Water ◽  
Experimental Ecosystems ◽  
Phytotoxic Effect ◽  
First Time ◽  
Upper Boundary

Phytotoxic effect of the heavy metal mixture polluted water has been investigated. The experimental microcosm water contained heavy metals (Zn, Сu, Pb, Cd, Fe+2, Fe+3, Cr+6, Ni). Metal concentrations have been selected to simulate water pollution with machine-building waste (slimes). Such an experiment has been carried out in vitro for the first time. Elodea canadensis macrophite as one of the most adopted and wide-spread species was incubated into the microcosms. No phytotoxic effect was recorded in the microcosms with plants and admixture of heavy metals over the first three days. The death of plants was detected 168 hours (7 days) after the start of incubation. Microcosms with plants without adding of the metals did not alter after the start of incubation. On the second day after incubation and orange sediment precipitated in the microcosms without macrophytes but with the heavy metals adding. The investigation results supplement the vision concerning polyfunctional role of hydrocoles in the elements migration within aquatic ecosystems. The obtained data indicated the prospective and promising character of further research of Elodea canadensis in terms of phytomefitation and search for the upper boundary of tolerance to heavy metals.

scholarly journals Motor responses of human gastrointestinal tract to 5-hydroxytryptamine in vivo and in vitro

Gut ◽  
1966 ◽  
Vol 7 (3) ◽  
pp. 208-216 ◽  
Author(s):  
J. J. Misiewicz ◽  
S. L. Waller ◽  
M. Eisner
Keyword(s):  
Gastrointestinal Tract ◽  
Human Gastrointestinal Tract ◽  
Motor Responses

scholarly journals Insulin differentially affects the distribution kinetics of amyloid beta 40 and 42 in plasma and brain

2017 ◽  
Vol 38 (5) ◽  
pp. 904-918 ◽  
Author(s):  
Suresh Kumar Swaminathan ◽  
Kristen M Ahlschwede ◽  
Vidur Sarma ◽  
Geoffry L Curran ◽  
Rajesh S Omtri ◽  
...  
Keyword(s):  
Amyloid Beta ◽  
Amyloid Beta Peptides ◽  
Beta Peptides ◽  
Distribution Kinetics ◽  
In Vitro Bbb Model ◽  
First Time ◽  
Kinetics Of ◽  
The Brain ◽  
Distinct Distribution

Impaired brain clearance of amyloid-beta peptides (Aβ) 40 and 42 across the blood–brain barrier (BBB) is believed to be one of the pathways responsible for Alzheimer’s disease (AD) pathogenesis. Hyperinsulinemia prevalent in type II diabetes was shown to damage cerebral vasculature and increase Aβ accumulation in AD brain. However, there is no clarity on how aberrations in peripheral insulin levels affect Aβ accumulation in the brain. This study describes, for the first time, an intricate relation between plasma insulin and Aβ transport at the BBB. Upon peripheral insulin administration in wild-type mice: the plasma clearance of Aβ40 increased, but Aβ42 clearance reduced; the plasma-to-brain influx of Aβ40 increased, and that of Aβ42 reduced; and the clearance of intracerebrally injected Aβ40 decreased, whereas Aβ42 clearance increased. In hCMEC/D3 monolayers (in vitro BBB model) exposed to insulin, the luminal uptake and luminal-to-abluminal permeability of Aβ40 increased and that of Aβ42 reduced; the abluminal-to-luminal permeability of Aβ40 decreased, whereas Aβ42 permeability increased. Moreover, Aβ cellular trafficking machinery was altered. In summary, Aβ40 and Aβ42 demonstrated distinct distribution kinetics in plasma and brain compartments, and insulin differentially modulated their distribution. Cerebrovascular disease and metabolic disorders may disrupt this intricate homeostasis and aggravate AD pathology.

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