Sense and Sensibility of Oxygen in Pathophysiology Using EPR Oximetry

‘Pray, pray be composed,’ cried Elinor, ‘and do not betray what you feel to every body present. Perhaps he has not observed you yet.’ For Elinor Dashwood, sensible and sensitive, and her romantic, impetuous younger sister Marianne, the prospect of marrying the men they love appears remote. In a world ruled by money and self-interest, the Dashwood sisters have neither fortune nor connections. Concerned for others and for social proprieties, Elinor is ill-equipped to compete with self-centred fortune-hunters like Lucy Steele, whilst Marianne’s unswerving belief in the truth of her own feelings makes her more dangerously susceptible to the designs of unscrupulous men. Through her heroines’ parallel experiences of love, loss, and hope, Jane Austen offers a powerful analysis of the ways in which women’s lives were shaped by the claustrophobic society in which they had to survive.

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Evaluation of a Refined Implantable Resonator for Deep-Tissue EPR Oximetry in the Clinic

Applied Magnetic Resonance ◽

10.1007/s00723-021-01376-5 ◽

2021 ◽

Author(s):

Eunice Y. Chen ◽

Dan Tse ◽

Huagang Hou ◽

Wilson A. Schreiber ◽

Philip E. Schaner ◽

...

Keyword(s):

Deep Tissue ◽

Epr Oximetry

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Photoreactivity of Hair Melanin from Different Skin Phototypes—Contribution of Melanin Subunits to the Pigments Photoreactive Properties

International Journal of Molecular Sciences ◽

10.3390/ijms22094465 ◽

2021 ◽

Vol 22 (9) ◽

pp. 4465

Author(s):

Krystian Mokrzynski ◽

Shosuke Ito ◽

Kazumasa Wakamatsu ◽

Theodore G. Camenish ◽

Tadeusz Sarna ◽

...

Keyword(s):

Chemical Composition ◽

Singlet Oxygen ◽

Near Infrared ◽

Paramagnetic Resonance ◽

Time Resolved ◽

W Band ◽

Epr Oximetry ◽

X Band ◽

Hair Samples ◽

Electron Paramagnetic

Photoreactivity of melanin has become a major focus of research due to the postulated involvement of the pigment in UVA-induced melanoma. However, most of the hitherto studies were carried out using synthetic melanin models. Thus, photoreactivity of natural melanins is yet to be systematically analyzed. Here, we examined the photoreactive properties of natural melanins isolated from hair samples obtained from donors of different skin phototypes (I, II, III, and V). X-band and W-band electron paramagnetic resonance (EPR) spectroscopy was used to examine the paramagnetic properties of the pigments. Alkaline hydrogen peroxide degradation and hydroiodic acid hydrolysis were used to determine the chemical composition of the melanins. EPR oximetry and spin trapping were used to examine the oxygen photoconsumption and photo-induced formation of superoxide anion, and time-resolved near infrared phosphorescence was employed to determine the singlet oxygen photogeneration by the melanins. The efficiency of superoxide and singlet oxygen photogeneration was related to the chemical composition of the studied melanins. Melanins from blond and chestnut hair (phototypes II and III) exhibited highest photoreactivity of all examined pigments. Moreover, melanins of these phototypes showed highest quantum efficiency of singlet oxygen photogeneration at 332 nm and 365 nm supporting the postulate of the pigment contribution in UVA-induced melanoma.

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