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Abstract  

In the Egyptian society, it is usual until now that females wear extensively gold jewelry since their birth. The present work is carried out to determine gold content in scalp hair samples from some selected female donors of various ages. Instrumental Neutron Activation Analysis, with gamma ray spectrometry was applied for this study. The obtained data are compared with the available published data for analysis of hair samples from other countries. The correlation between age and gold concentration in hair samples is discussed. Interpretation of the influence of other factors which possibly may affect the contents of gold in the analyzed hair samples is also presented.

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Abstract  

Autopsy of 29-year old woman suspicious of committing suicide by the ingestion of As2O3 yielded contradictory findings. All pathological findings as well as clinical symptoms suggested acute poisoning, while a highly elevated As level of 26.4 μg g−1 in her hair collected at the autopsy, which was determined with inductively coupled plasma mass spectrometry indicated chronic poisoning. To elucidate this discrepancy, instrumental neutron activation analysis (INAA) with proven accuracy was performed of another set of sectioned hair samples. Levels of As found by INAA in the range of 0.16–0.26 μg g−1 excluded chronic poisoning, because the person died after approximately 14 h after the As2O3 ingestion. Two reasons for the discordant As results obtained by ICP-MS and INAA are considered: (1) accidental, non-removed contamination of hair on the As2O3 ingestion; (2) erroneous performance of ICP-MS.

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Abstract  

Scalp hair is routinely used to assess exposure to toxic trace elements and nutritional status of some required trace elements. The advantages and disadvantages of hair as a biologic monitor have been comprehensively discussed in the literature for many years. Among the concerns is distinguishing between exogenous and endogenous contributions. Nested in this issue is the longitudinal distribution of a trace element along the hair strand. The typical observation for many elements of interest is that the element concentration increases from the root end to the distal end; and this is attributed to continuing contamination from exogenous sources. In this study we used neutron activation analysis to measure 14 trace elements in 6 mm segments of full-length scalp hair from three healthy members of the same household having light-urban environmental exposure. To extend the data set for selenium, we included three adult female subjects with longer than average scalp hair. From these trace-element concentrations we calculated the root-to-distal end ratios as a profile diagnostic of trace-element distributions. Ratios fall into three diagnostic categories, >1, ≈1, and <1 corresponding to profiles having decreasing root-to-distal concentrations, unchanging concentrations, and increasing concentrations, respectively. Of the 14 elements measured, only Se has R > 1, Zn and S have R ≈ 1, and the remaining 11 elements all have R < 1 in the order: As > I > Hg ≈ Au ≈ Mg ≈ Mn ≈ Sb ≈ Ca > Cu > Al ≈ Ag. R Se is greater than 1 and increases with hair length (P = 0.02) corresponding to a continuous longitudinal loss of Se in stark and puzzling contrast to the other elements measured. An analogous loss of Se in the nail monitor was not observed leading us to conclude that the nail is less prone to misclassification of selenium status in epidemiological studies.

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Abstract  

Hair samples from junior high school students in metropolitan areas of Taichung, Taiwan were tested for a total of 13 elements, Al, Ag, Br, Cl, Cr, Fe, K, La, Mn, Na, Sc, Se, and Zn by instrumental neutron activation analysis (INAA) to establish seasonal variations, gender and environmental exposures. The seasonal variations of hairs in 39 healthy students (18 males and 21 females; age 13.3 ± 0.4 years; height, 158.0 ± 4.1 cm; weight, 53.4 ± 5.7 kg) were collected at 1.5-month intervals for 1 year starting from late August, 2008. The concentrations of the above elements varied from 103 to 10−2 μg g−1 at different sampling times. A quantified index of agreement (AT) was introduced to help classify the elements. A smaller AT indicated highly consistent quantities of specific metals in the hair while a larger AT indicated increased fluctuation, i.e., less agreement. The different ATs in various hair samples were discussed. The concentrations of these elements are compared with the data in the literature.

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Abstract  

The street children phenomenon is an increasing problem in most cities of the world including Isfahan, which is a fast growing town. The number of street children with the growth of the town is increased. It is therefore important to have baseline data on their health problems. Hair element analysis remains an important tool in the nutritional and environmental assessment of them. A measurement of the elemental concentration in recently-grown hair provides an integrated view of the element status in the follicular cells and their blood supply, unaffected by short term fluctuations in the nutrient intake of the subject. This study aimed to assess heavy metals concentrations in the hair of street children in Isfahan using neutron activation analysis method. The concentration of heavy metals (Cu, Cr, Fe, Hg, Mn, and Zn) of 17 Iranian street children (Isfahan) was examined. Data analysis found that different profiles of the concentrations of Cr, Hg, Mn, and Zn were seen in each sample. These results were discussed with reference to show of environmental effects.

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Journal of Thermal Analysis and Calorimetry
Authors: C. Barba, M. Martí, A. Roddick-Lanzilotta, A. Manich, J. Carilla, J. Parra, and L. Coderch

Abstract  

Most beauty care products and treatments primarily affect the cuticle layers of hair fibers. The resulting damage has an adverse effect on hair water absorption. Water changes a wide variety of properties of human hair and is therefore of fundamental interest. Wool proteins are mild, natural, biodegradable, and sustainably produced with multiple functionalities and potential for use in the personal care and detergent market. In this study, the effect on hair water sorption of two types of keratin samples obtained from wool is investigated. Modifications of hair water sorption due to a bleaching treatment have been demonstrated, with lower values of water sorption capacity and an increase of the fibers permeability. Applications of keratin peptides and proteins to bleached hair improved the water sorption properties of the fibers and reduced their permeability.

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Orvosi Hetilap
Authors: Melinda Erdős, Beáta Tóth, Zsuzsanna Almássy, László Tímár, and László Maródi

McKusick, V. A.: Metaphyseal dysostosis and thin hair: a „new” recessively inherited syndrome? Lancet, 1964, 1 , 832–833. McKusick V. A

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Journal of Thermal Analysis and Calorimetry
Authors: Robson Miranda da Gama, Tatiana Santana Balogh, Simone França, Tânia Cristina Sá Dias, Valcinir Bedin, André Rolim Baby, Jivaldo do Rosário Matos, and Maria Valéria Robles Velasco

Introduction The hair thread has a highly organized, cylindrical structure, formed by mostly keratinized inert cells which follow a very precise and pre-defined design [ 1 , 2 ]. The human hair is composed of about 65

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Journal of Behavioral Addictions
Authors: Erin M. Altenburger BA, Esther S. Tung, and Nancy J. Keuthen

McNally M A Jenike 1996 Trichotillomania and self-esteem: A survey of 62 female hair pullers Journal of Clinical Psychiatry

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Journal of Behavioral Addictions
Authors: Liana R. N. Schreiber, Katherine Lust, Brian Odlaug, Katherine L. Derbyshire, and Jon Grant

. C. A. Flessner V. S. Knopik J. McGeary 2012 Hair pulling disorder (trichotillomania): Genes

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