Fabrication of visible marker on living body-derived materials for ultrasonography by sputtering technology

The redox reaction of the neurotransmitter dopamine at the carbon fibre microelectrode was studied by several electrochemical methods. It was found that under conditions usual in a living body, the diffusion current fullfils, within experimental errors, the behavior theoretically predicted by the Cottrell equation. Nevertheless, attention should be paid to the fact that unsupported or weakly supported conditions give rise to a non-Cottrell response of diffusion current. Moreover, similar changes were observed if the dopamine concentration was either lower such as several units of μmol l-1, or about 100 μmol l-1 or higher. The non-Cottrell behavior of diffusion current involves the nonlinearity of the dopamine calibration curve obtained by pulse techniques. The present work is aimed at pointing out that such behavior of the measured data could lead to misinterpretation of the obtained dopamine concentration. Similar features could be also achieved for the other catecholamines.

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Melanogenesis Connection with Innate Immunity and Toll-Like Receptors

International Journal of Molecular Sciences ◽

10.3390/ijms21249769 ◽

2020 ◽

Vol 21 (24) ◽

pp. 9769

Author(s):

Saaya Koike ◽

Kenshi Yamasaki

Keyword(s):

Skin Pigmentation ◽

Innate Immune ◽

Mitogen Activated Protein Kinase ◽

Ultraviolet Rays ◽

Toll Like Receptors ◽

Pigment Formation ◽

Living Body ◽

Pigmentary Disorders ◽

Wide Range ◽

Griscelli Syndrome

The epidermis is located in the outermost layer of the living body and is the place where external stimuli such as ultraviolet rays and microorganisms first come into contact. Melanocytes and melanin play a wide range of roles such as adsorption of metals, thermoregulation, and protection from foreign enemies by camouflage. Pigmentary disorders are observed in diseases associated with immunodeficiency such as Griscelli syndrome, indicating molecular sharing between immune systems and the machineries of pigment formation. Melanocytes express functional toll-like receptors (TLRs), and innate immune stimulation via TLRs affects melanin synthesis and melanosome transport to modulate skin pigmentation. TLR2 enhances melanogenetic gene expression to augment melanogenesis. In contrast, TLR3 increases melanosome transport to transfer to keratinocytes through Rab27A, the responsible molecule of Griscelli syndrome. TLR4 and TLR9 enhance tyrosinase expression and melanogenesis through p38 MAPK (mitogen-activated protein kinase) and NFκB signaling pathway, respectively. TLR7 suppresses microphthalmia-associated transcription factor (MITF), and MITF reduction leads to melanocyte apoptosis. Accumulating knowledge of the TLRs function of melanocytes has enlightened the link between melanogenesis and innate immune system.

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On the transcendental undercurrents of phenomenology: the case of the living body

Continental Philosophy Review ◽

10.1007/s11007-021-09534-z ◽

2021 ◽

Author(s):

Sara Heinämaa

Keyword(s):

Lived Body ◽

Living Body ◽

Special Scientific ◽

Mutual Relations ◽

Scientific Debates

AbstractToday the phenomenological concept of the lived body figures centrally in several philosophical and special scientific debates. In these wide and widening fields, the concept is used with multiple different meanings. In order to clarify and delineate the debates, this paper provides an explication of the phenomenological-transcendental methods. It argues that these methods help us remove the most fundamental ambiguities of the concept of embodiment by distinguishing between the main constituents of the lived body and by illuminating their mutual relations.

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Surface Reformation of Medical Devices with DLC Coating

Materials ◽

10.3390/ma14020376 ◽

2021 ◽

Vol 14 (2) ◽

pp. 376

Author(s):

Mao Kaneko ◽

Masanori Hiratsuka ◽

Ali Alanazi ◽

Hideki Nakamori ◽

Kazushige Namiki ◽

...

Keyword(s):

High Pressure ◽

Medical Devices ◽

Diamond Like Carbon ◽

Steam Sterilization ◽

Dlc Coatings ◽

Chrome Plating ◽

Living Body ◽

Dlc Coating ◽

Pressure Steam ◽

Adhesion Friction

We evaluated the adhesion, friction characteristics, durability against bodily acids, sterilization, cleaning, and anti-reflection performance of diamond-like carbon (DLC) coatings formed as a surface treatment of intracorporeal medical devices. The major coefficients of friction during intubation in a living body in all environments were lower with DLC coatings than with black chrome plating. DLC demonstrated an adhesion of approximately 24 N, which is eight times stronger than that of black chrome plating. DLC-coated samples also showed significant stability without being damaged during acid immersion and high-pressure steam sterilization, as suggested by the results of durability tests. In addition, the coatings remained unpeeled in a usage environment, and there was no change in the anti-reflection performance of the DLC coatings. In summary, DLC coatings are useful for improving intracorporeal device surfaces and extending the lives of medical devices.

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