Genetic Influences on Hormonal Markers of Chronic HPA Function in Human Hair

AbstractCortisol is the primary output of the hypothalamic-pituitary-adrenal (HPA) axis and is central to the human biological stress response, with wide-ranging effects on physiological function and psychiatric health. In both humans and animals, cortisol is frequently studied as a biomarker for exposure to environmental stress. Relatively little attention has been paid to the possible role of genetic variation in heterogeneity in chronic cortisol, in spite of well-studied biological pathways of glucocorticoid function. Using recently developed technology, hair samples can now be used to measure accumulation of cortisol over several months. In contrast to more conventional salivary measures, hair cortisol is not influenced by diurnal variation or transient hormonal reactivity. In an ethnically and socioeconomically diverse sample of 1 070 child and adolescent twins and multiples from 556 unique families, we estimated genetic and environmental influences on hair concentrations of cortisol and its inactive metabolite, cortisone. We identified sizable genetic influences on cortisol that decrease with age, concomitant with genetic influences on cortisone that increase with age. Shared environmental influences on cortisol and cortisone were modest and, for cortisol, decreased with age. Twin-specific, non-shared environmental contributions to cortisol and cortisone became increasingly correlated with age. We find some evidence for sex differences in the biometric contributions to cortisol, but no strong evidence for main or moderating effects of family socioeconomic status on cortisol or cortisone. This study constitutes the first genetic study of hormone concentrations in human hair, and provides the most definitive characterization to-date of age and socioeconomic influences on hair cortisol.

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Pathogenesis of Human Hair Defects

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005007x ◽

1974 ◽

Vol 32 ◽

pp. 12-13

Author(s):

P.S. Porter ◽

T. Aoyagi ◽

R. Matta

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Human Hair ◽

Standard Techniques ◽

Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

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Ruthenium Red Staining of Human Hard Keratin Fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054005 ◽

1982 ◽

Vol 40 ◽

pp. 278-279

Author(s):

M. C. Buhrer ◽

R. A. Mathews

Keyword(s):

Human Hair ◽

Ruthenium Red ◽

Acid Mucopolysaccharides ◽

Biochemical Studies ◽

Keratin Fibers ◽

Ruthenium Red Staining ◽

Extracellular Materials

Ruthenium red has been used as a stain to demonstrate a variety of extracellular materials, especially acid mucopolysaccharides. It also reacts with certain intracellular and extracellular lipids. Since biochemical studies in our laboratory demonstrated the presence of a variety of monosaccharides in human hair ruthenium red staining procedures were adopted in order to evaluate the presence and morphological location of acid oligosaccharides in the keratinized aspect of hair.

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Ultrastructure of Cryptorchidism and Seminoma

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099143 ◽

1981 ◽

Vol 39 ◽

pp. 540-541

Author(s):

Shirley Siew ◽

Susan C. James

Keyword(s):

Malignant Tumors ◽

Frozen Section ◽

Malignant Potential ◽

Genetic Influences ◽

Endocrine Gland ◽

Medial Aspect ◽

Left Testis ◽

Bilateral Orchiectomy

Testicular maldescent is the most common endocrine gland abnormality, as 2.7% of mature neonates are cryptorchid. The significant complications are that there is a disturbance of normal maturation which results in diminished fertility and there is an increase in the malignant potential which is 35 times greater in the undescended than the descended testis. It is considered that genetic influences may be of etiological importance and recurrence has been described in some families. It is of interest, that the case reported here has 2 siblings who have also presented with cryptorchidism and malignant tumors.The propositus is 14 years old. He is well developed (described by some as obese) and shows normal secondary male characteristics except for an immature scrotum. Laparotomy showed both testes to be intraabdominal. A hard nodule (0.5cm) was palpated on the medial aspect of the left testis. Frozen section showed the presence of seminoma and bilateral orchiectomy was performed.

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Human-hair analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124835 ◽

1992 ◽

Vol 50 (1) ◽

pp. 886-887

Author(s):

Brenda E. Lambert ◽

Ernest C. Hammond

Keyword(s):

Human Hair ◽

Hair Analysis ◽

Hair Shaft ◽

White Female ◽

Chemical Processing ◽

X Ray ◽

Hair Samples ◽

Wave Technique ◽

Permanent Wave ◽

Scanning Electron

The purpose of this study was to examine the external structure of four human hair shaft samples with the scanning Electron Microscope (SEM) and to obtain information regarding the chemical composition of hair by using the attached x ray microanalysis unit.The hair samples were obtained from two female subjects. Sample A was taken from a black female and had not undergone any type of chemical processing. Sample B, C, D were taken from a white female, and were natural, processed, and unpigmented, i.e. “gray”, respectively. Sample C had been bleached, tinted, and chemically altered using a permanent wave technique.

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Cosmetology treatments on human hair: An SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167160 ◽

1996 ◽

Vol 54 ◽

pp. 940-941

Author(s):

D.F. Bowling

Keyword(s):

High School ◽

High Resolution ◽

Human Hair ◽

Optical Microscope ◽

Convincing Evidence ◽

Brightness Contrast ◽

Sem Study

High school cosmetology students study the methods and effects of various human hair treatments, including permanents, straightening, conditioning, coloring and cutting. Although they are provided with textbook examples of overtreatment and numerous hair disorders and diseases, a view of an individual hair at the high resolution offered by an SEM provides convincing evidence of the hair‘s altered structure. Magnifications up to 2000X provide dramatic differences in perspective. A good quality classroom optical microscope can be very informative at lower resolutions.Students in a cosmetology class are initially split into two groups. One group is taught basic controls on the SEM (focus, magnification, brightness, contrast, specimen X, Y, and Z axis movements). A healthy, untreated piece of hair is initially examined on the SEM The second group cements a piece of their own hair on a stub. The samples are dryed quickly using heat or vacuum while the groups trade places and activities.

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