The intermediate filament structure of human hair

Wilk, Krystyna E.; James, Veronica J.; Amemiya, Yoshiyuki

doi:10.1016/0304-4165(95)00111-5

Cited by 35 publications

(29 citation statements)

References 13 publications

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“…Little is known about the geometrical distribution of molecules across the IF cross-section despite many efforts during the past 50 years. Various models have been developed, most of them consisting of ring or ring-core models (Bailey et al, 1965;Fraser et al, 1964aFraser et al, , 1976Fraser et al, , 1985Wilk et al, 1995). Based on equatorial X-ray scattering modelling, Briki et al (1998) showed that human hair IF corresponds to a uniform density cross-section, whilst porcupine quill IF is more consistent with a ring-core structure.…”

Section: Introductionmentioning

confidence: 97%

In vivo formation steps of the hard α-keratin intermediate filament along a hair follicle: Evidence for structural polymorphism

Er-Rafik

Briki

Burghammer

et al. 2006

Journal of Structural Biology

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Section: Introductionmentioning

confidence: 97%

In vivo formation steps of the hard α-keratin intermediate filament along a hair follicle: Evidence for structural polymorphism

Er-Rafik

Briki

Burghammer

et al. 2006

Journal of Structural Biology

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“…The first one, which we hereinafter call the ''Standard Protocol'', is known to have only been described in one publication by James. 17 The method has been referred to by James in several subsequent publications as the means by which diffraction data must be processed to facilitate the diagnosis of breast cancer. 1,3,12,13,15 Laaziri and co-workers 11 also reference this method as the technique they used for data reduction in their attempt to replicate the findings of James.…”

Section: Image Analysismentioning

confidence: 99%

“…In James' commentary on the work of Laaziri et al, 15 James discusses the quality of images required to perform the diagnosis of breast cancer and shows one-dimensional data extracted from diffraction patterns she has processed, but does not describe the actual processing method other than by referring to the previously published material. 2,17,23,33 None of these referenced works contain a complete method that could be used by an independent observer to determine the incidence of breast cancer from an X-ray diffraction pattern. Whether or not the parameters and methods used to process the Xray diffraction patterns by James have been developed since first published is unknown, but a clear and concise description of the complete method to process the X-ray diffraction patterns to diagnose breast cancer remains unpublished.…”

mentioning

confidence: 99%

Diagnosis of breast cancer by X‐ray diffraction of hair

Corino¹,

French²

2007

Intl Journal of Cancer

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This article presents the results of analyses of hair fibers from women with breast cancer using synchrotron-derived X-ray diffraction. These diffraction patterns contained a new feature superimposed on the normal diffraction pattern of a-keratin. The feature appeared as a ring with a molecular spacing determined to be 4.76 6 0.07 nm. This feature was not present in the diffraction patterns of hair from women without breast cancer as assessed by other routine clinical diagnostic techniques. Furthermore, different hairs from the same subject analysed on two different synchrotron beamlines give remarkably consistent diffraction patterns. Previous studies by other investigators have suggested that analysis of X-ray diffraction patterns of hair can reveal the presence of breast cancer in clinical and preclinical trials. This finding, however, has not been independently confirmed. The methodologies of sample handling, sample exposure and image analysis are known to be vital. We discuss some of these issues and provide a detailed description of the methodology employed for the sample handling and image analysis and new methodologies developed from this work. We conclude that X-ray diffraction of hair has the potential to provide a non-invasive test for the presence of breast cancer. ' 2007 Wiley-Liss, Inc.Key words: X-ray diffraction; hair; breast cancer; synchrotron In 1999 James et al. reported differences in the X-ray diffraction patterns of hair from individuals with breast cancer compared to healthy subjects.1 The X-ray diffraction patterns of hair from cancer patients contained a ring of comparatively low intensity, which was superimposed on the normal a-keratin pattern obtained from healthy control subjects and which corresponded to a molecular spacing of d 5 4.44 nm. This ring was reportedly observed in all samples of scalp and/or pubic hair taken from women diagnosed with breast cancer, as well as from subjects ''not yet diagnosed with breast cancer but suspected of being at risk''. In other words, a number of false positives were identified. Subsequent papers by James and coworkers reported X-ray diffraction analysis results of blinded human samples, which were consistent with the initial publication.2,3 The later paper reported on the results of 503 blinded hair sample analyses and demonstrated a sensitivity of 100% (no false negatives) and a specificity of 86% (14% false positives by comparison to mammography) for breast cancer.However, the finding remained highly controversial as several groups independent of James attempted to replicate the original findings and all were unsuccessful. [4][5][6][7][8][9][10][11] The technical explanations for these replication failures [12][13][14][15][16] provide insight into the experimental challenges. Myer et al., 9 whose diffraction data was not of sufficient quality to demonstrate a correlation between an altered X-ray diffraction pattern and the presence of breast cancer, sent the 27 samples they had examined to James who subsequently performed X-ray diffraction a...

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“…Then the IFs are embedded in an amorphous matrix with a high sulfur content to form the macrofibrils and the cortical cells (Leon, 1972;Wolfram, 2003). Previous studies have shown that this multi-scale organization did not differ according to the type of hair studied or the ethnic origin (Wilk et al, 1995;Franbourg et al, 2003). The fiber-matrix composite structure and the orientation of the IFs along the longitudinal axis are responsible for the anisotropic mechanical properties of hairs (Robbins, 2012).…”

Section: Introductionmentioning

confidence: 96%