Search PubMedSearch

PubMed · 2964988

Bioengineering and the patch test.

Abstract

Several non-invasive techniques based on different physical principles have been developed to investigate skin function and have been used for patch test assessment. In the present paper, the advantages and the defects of these methods are described in the light of the more recent data available in literature. Meanwhile, the eye and the fingers still remain the simplest method to assess skin irritancy. Bioengineering techniques could provide efficient recording systems for monitoring skin color, skin blood flow and barrier function damage, useful to the investigator rather than to the clinician.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

E Berardesca, H I Maibach. 1988. Bioengineering and the patch test.. https://doi.org/10.1111/j.1600-0536.1988.tb05481.x

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Selective and sensitive colorimetric sensing of carbosulfan based on BiO2-x/Bi2O2.75 nanosheets with excellent haloperoxidase-like activity.

The development of colorimetric methods based on directly inhibiting nanozyme activity for pesticide detection has attracted considerable attention. In this study, we report a novel colorimetric sensing strategy utilizing BiO2-x/Bi2O2.75 nanosheets (BiO2-x/Bi2O2.75 NSs) with haloperoxidase (HPO)-like activity for the rapid and sensitive detection of carbosulfan (CBS) in foods. Oxygen-vacancy-rich BiO2-x/Bi2O2.75 NSs with HPO-like activity were rationally constructed. Kinetic studies revealed a remarkable Michaelis-Menten constant (Km) of 0.014 mM for I-, indicating a higher affinity for iodide ions than other reported HPO-like nanozymes, as evidenced by its lower Km. Under acidic conditions, CBS tends to be hydrolyzed to produce reductive sulfide species, which directly inhibit the iodoperoxidase-like activity of BiO2-x/Bi2O2.75 NSs, enabling selective detection with a limit of detection (LOD) of 0.18 μg/mL and a linear range of 0.20-100 μg/mL. When the concentration of interfering pesticides and substances was 5 times that of CBS, the sensor remained unaffected, exhibiting excellent stability and specificity. This work contributes to the detection of CBS in complex food matrices, bridging the application gap of HPO-like nanozymes in pesticide detection and providing a promising method for food safety detection.

Colorimetry

A tetrazolium-based colorimetric assay for quantification of HIV-1-induced cytopathogenicity in monocyte-macrophages exposed to macrophage-colony-stimulating factor.

A sensitive assay was developed for in vitro evaluation of anti-HIV agents in monocyte-macrophage cells (M/M) (a crucial target of HIV in the body). Monocyte-macrophage cells are usually poorly sensitive to the cytopathic effect induced by HIV. However, when fresh adherent monocyte-macrophage cells are cultured at relatively high density in the presence of macrophage-colony stimulating factor (M-CSF), they undergo cytolysis and die in 2-3 weeks. HIV-mediated cell-killing can thus be assessed with a method based on the reduction of the yellow colored 3-(4-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) by metabolically active cells to a blue formazan, which can be measured spectrophotometrically. HIV-mediated cytopathic effect of M-CSF-exposed monocyte-macrophage cells was consistently achieved in all experiments performed under the conditions described herein. Anti-HIV activity of zidovudine (AZT) was also comparatively evaluated in M-CSF- and normal monocyte-macrophage cells both using the MTT assay and by measuring HIV-p24 antigen production in supernatants of monocyte-macrophage cells cultures, and similar results obtained with both methods. These results support the use of this colorimetric assay for broad screening of anti-HIV agents in monocyte-macrophage cells.

Colorimetry