PERCUTANEOUS ABSORPTION OF 2,4-DICHLOROPHENOXYACETIC ACID FROM SOIL WITH RESPECT TO SOIL LOAD AND SKIN CONTACT TIME: IN VIVO ABSORPTION IN RHESUS MONKEY AND IN VITRO ABSORPTION IN HUMAN SKIN

AbstractIn vitro cultures of Leucojum aestivum are considered as an alternative for the production of galanthamine, which is used for the symptomatic treatment of Alzheimer’s disease. We studied the effects of auxins 2,4-dichlorophenoxyacetic acid (2,4-D), 4-amino-3,5,6-trichloropicolinic acid (picloram), 3,6-dichloro-o-anisic acid (dicamba) at concentrations of 25 and 50 µM on the induction of embryogenic callus and its capacity to induce somatic embryogenesis and alkaloid accumulation. The embryogenic response of the explants was from 30% for 25 µM of dicamba to 100% for picloram (for both 25 and 50 µM). 2,4-D (50 µM) stimulated greater callus proliferation and somatic embryo induction as compared to the other auxins. Polyethylene glycol (PEG) stimulated somatic embryo maturation. Callus grown on media containing 50 µM of auxins produced fewer phenolic compounds as compared with callus grown on media containing 25 µM of auxins. GC-MS analyses showed seven alkaloids in the in vivo bulbs and two to four in callus culture. Galanthamine was detected in callus cultivated with 2,4-D (25, 50 µM), picloram (25 µM), and dicamba (50 µM). Other alkaloids, trisphaeridine, tazettine, and 11-hydroxyvittatine were accumulated only in callus growing on medium with picloram (50 µM).

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In Vivo Percutaneous Absorption of Boric Acid, Borax, and Disodium Octaborate Tetrahydrate in Humans Compared to in Vitro Absorption in Human Skin from Infinite and Finite Doses

Toxicological Sciences ◽

10.1093/toxsci/45.1.42 ◽

1998 ◽

Vol 45 (1) ◽

pp. 42-51 ◽

Cited By ~ 1

Author(s):

Ronald C. Wester ◽

Xiaoying Hui ◽

Tracy Hartway ◽

Howard I. Maibach ◽

Kathleen Bell ◽

...

Keyword(s):

Boric Acid ◽

Human Skin ◽

Percutaneous Absorption ◽

Disodium Octaborate Tetrahydrate ◽

In Vivo Percutaneous Absorption

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Correction to: Predicting in vivo absorption of chloramphenicol in frogs using in vitro percutaneous absorption data

BMC Veterinary Research ◽

10.1186/s12917-021-02860-7 ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Victoria K. Llewelyn ◽

Lee Berger ◽

Beverley D. Glass

Keyword(s):

Percutaneous Absorption ◽

Absorption Data ◽

In Vivo Absorption ◽

In Vitro Percutaneous Absorption

An amendment to this paper has been published and can be accessed via the original article.

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In vivo and in vitro instability of B chromosomes in palmarosa grass (Cymbopogon martinii var. motia)

Genome ◽

10.1139/g88-153 ◽

1988 ◽

Vol 30 (6) ◽

pp. 966-973 ◽

Cited By ~ 7

Author(s):

H. L. Sreenath ◽

K. S. Jagadishchandra

Keyword(s):

Germ Line ◽

Chromosome Instability ◽

Metaphase Plate ◽

B Chromosome ◽

B Chromosomes ◽

Dichlorophenoxyacetic Acid ◽

Cymbopogon Martinii ◽

2,4 Dichlorophenoxyacetic Acid

Meiotic and mitotic instability and elimination of B chromosomes was observed in diploid palmarosa (Cymbopogon martinii var. motia) with 2n = 20 + 1–2 B under in vivo and in vitro conditions. Under in vivo conditions B chromosomes were totally absent from the roots but preferentially transmitted in the germ line tissues. When present as a pair, the B chromosomes formed bivalents showing almost regular orientation, congression, and disjunction. When present singly, the B chromosome formed a univalent and did not pair with any of the A chromosomes and showed nonalignment on the metaphase plate during metaphase I. Immature inflorescences of a race of palmarosa with 2n = 20 + 2 B were cultured on Murashige and Skoog's medium containing 1 mg/L of 2,4-dichlorophenoxyacetic acid to produce embryogenic callus. The cytological analysis of the callus revealed only 20 A chromosomes in nearly all the cells, both the B chromosomes being eliminated. From this callus, plantlets without B chromosomes were regenerated on MS medium without growth regulators and established in the soil. The regenerated plants exhibited 20 A chromosomes with normal meiosis.Key words: Cymbopogon martinii, chromosome instability, palmarosa grass, B chromosomes, tissue culture, plant regeneration.

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In vitro and in vivo percutaneous absorption of 14C-chloroform in humans

Human & Experimental Toxicology ◽

10.1177/096032719501400305 ◽

1995 ◽

Vol 14 (3) ◽

pp. 260-265 ◽

Cited By ~ 9

Author(s):

D. Dick ◽

Kme Ng ◽

DN Sauder ◽

I. Chu

Keyword(s):

Human Skin ◽

Percutaneous Absorption ◽

Low Dose ◽

Dermal Absorption ◽

High Dose ◽

Distilled Water ◽

Applied Dose ◽

Flow Through

Chloroform has been found in potable water and there is concern that significant dermal absorption may arise from daily bathing and other activities. The present study examines percutaneous absorption of 14C-chloroform in vivo using human volunteers and in vitro using fresh, excised human skin in a flow-through diffusion cell sys tem. Fifty microlitre doses of either 1000 μg ml-1 chloro form in distilled water, (16.1 μg cm-2) or 5000 μg ml-1 of chloroform in ethanol, (80.6 μg cm-1) were applied to the forearm of volunteers with exhaled air and urine being collected for analysis. Single doses of either 0.4 μg ml-1 chloroform in distilled water (low dose, 0.62 μg cm-2, 1.0 ml dosed) or 900 μg ml-1 chloroform in distilled water (high dose, 70.3 μg cm -2, 50 μl dosed) were applied to discs of the excised abdominal skin placed in flow-through dif fusion cells and perfused with Hepes buffered Hank's bal anced salt solution, with a wash at 4 h. In vivo absorption was 7.8 ± 1.4% (water as vehicle) and 1.6 ± 0.3% (ethanol as vehicle). Of the dose absorbed in vivo, more than 95% was excreted via the lungs (over 88% of which was CO2), and the maximum pulmonary excretion occurred between 15 min and 2 h after dosing. The percentage of dose absorbed in vitro (skin + perfusate) was 5.6 ± 2.7% (low dose) and 7.1 ± 1.4% (high dose). The above data demon strate that a significant amount of the dissolved chloro form penetrates through the human skin, and that a higher percentage of the applied dose was absorbed using water as vehicle. In addition, the in vitro method offers a good estimate for in vivo data.

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