摘要:

Using a new computerized methodological procedure a separate analysis and a quantitative determination of the viscous and elastic parameters of the scalp hair shaft were performed in 37 neonates of both sexes with a gestational age of 28-29 weeks (n = 16) and 39-40 weeks (n = 21), respectively. A statistically significant (p < 0.001) decrease in the values of modulus of elasticity (Eα) was found in the hair shaft of premature neonates, as compared to the full-term ones, whereas the values of postyield slope (Eβ) and of SDIS/SSTOR (viscous parameter) did not significantly differ in the two groups. The decrease in modulus of elasticity in the hair shaft of premature neonates may be interpreted in terms of an insufficient number of disulphide bonds between the α-helical keratin units of the hair cortex or of a disordered arrangement of microfibrils within the matrix. Further studies are now warranted to determine the pattern of mechanical parameters of the scalp hair shaft in large numbers of newborn infants of different gestational ages and to answer the question as to whether this pattern might be useful in the accurate postnatal assessment of fetal maturati

ISSN:0302-3427    

DOI:10.1159/000211519

出版商:S. Karger AG    

年代:1997

数据来源: Karger

摘要:

We measurd the superoxide dismutase (SOD) activity in human skin from tissue homogenates after topical application of hydrocortisone-21 -acetate and clobetasol proprionate, dissolved in propylene glycol. SOD was measured spectropho-tometrically. SOD activity was higher in the treated skin than in the control untreated skin. We separated epidermis from the dermis by curettage and measured the level of SOD in each homogenized layer; SOD activity was higher in the epidermis compared to the dermis in untreated skin. After corticoid application, SOD activity was higher in the dermis compared to the epidermis to a degree dependent on corticoid potency. These experiments demonstrate that the epidermis may have a role in the barrier function of the skin by its antioxidant capacity and that the dermis is the major location of the metabolic activity in the skin. On the other hand, our results suggest that these corticosteroids may stimulate SOD production and may release antioxidants. This could be another anti-inflammatory property of corticosteroids.

ISSN:0302-3427    

DOI:10.1159/000211520

出版商:S. Karger AG    

年代:1997

数据来源: Karger

ISSN:0302-3427    

DOI:10.1159/000211521

出版商:S. Karger AG    

年代:1997

数据来源: Karger

ISSN:0302-3427    

DOI:10.1159/000211522

出版商:S. Karger AG    

年代:1997

数据来源: Karger

ISSN:0302-3427    

DOI:10.1159/000211523

出版商:S. Karger AG    

年代:1997

数据来源: Karger

ISSN:0302-3427    

DOI:10.1159/000211524

出版商:S. Karger AG    

年代:1997

数据来源: Karger

ISSN:0302-3427    

DOI:10.1159/000211508

出版商:S. Karger AG    

年代:1997

数据来源: Karger