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1.
Various animal models have been employed for research on the significance of measuring trace element concentrations in the human scalp hair. The objects of such research were the establishment of relationships between the concentrations of trace elements in human scalp hair and (1) their concentrations in other compartments of the human body or (2) specific pathophysiological conditions. The guinea pig appears to be the animal of choice for such studies because the elemental composition and growth pattern of its hair parallel those of the human scalp hair.  相似文献   

2.
The adverse health effects linked with chromium and manganese and the diverse cellular and molecular effects of chromium and manganese make the study of chromium and manganese carcinogenesis and toxicology very interesting and complex. Quantitative elemental analysis of scalp hair of breast cancer patients (stage III) (n=26) and controls (n=27) were used to study to find correlation and possible changes between breast cancer and healthy controls. The graphite furnace atomic absorption analysis of quantitative method was used for the determination of chromium and manganese element levels. Comparison of mean elemental contents of the breast cancer patients with controls shows a significant enhancement of chromium (p<0.05) but declining trends for manganase (p<0.05) in breast cancer patients. Changes in element content in hair can serve as a guide to opening up new vistas in the treatment of breast cancer on the basis of an overall analysis of symptoms and signs.  相似文献   

3.
We report isotopic data (δ2H, δ18O n = 196; δ13C, δ15N n = 142; δ34S n = 85) from human hair and drinking water (δ2H, δ18O n = 67) collected across China, India, Mongolia, and Pakistan. Hair isotope ratios reflected the large environmental isotopic gradients and dietary differences. Geographic information was recorded in H and O and to a lesser extent, S isotopes. H and O data were entered into a recently developed model describing the relationship between the H and O isotope composition of human hair and drinking water in modern USA and pre‐globalized populations. This has anthropological and forensic applications including reconstructing environment and diet in modern and ancient human hair. However, it has not been applied to a modern population outside of the USA, where we expect different diet. Relationships between H and O isotope ratios in drinking water and hair of modern human populations in Asia were different to both modern USA and pre‐globalized populations. However, the Asian dataset was closer to the modern USA than to pre‐globalized populations. Model parameters suggested slightly higher consumption of locally producedfoods in our sampled population than modern USA residents, but lower than pre‐globalized populations. The degree of in vivo amino acid synthesis was comparable to both the modern USA and pre‐globalized populations. C isotope ratios reflected the predominantly C3‐based regional agriculture and C4 consumption in northernChina. C, N, and S isotope ratios supported marine food consumption in some coastal locales. N isotope ratios suggested a relatively low consumption of animal‐derived products compared to western populations. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

4.
The influence of hair color on the trace elemental status in horse's hair has been studied. A current analytical technique such as particle-induced X-ray emission (PIXE) used in this study has provided reliable, rapid, easy, and relatively inexpensive diagnostic methods. Twenty-eight elements (Al, Br, Ca, Cl, Co, Cu, Cr, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, S, Se, Si, Sr, Ti, V, Y, and Zn) in mane hair were detected by the PIXE method. The gray hair contains significantly greter amounts of Cu, Ti, and Zn, and lower amounts of Br, Ca, Se, and Sr than those in other colored horse hairs (p<0.05). Those results measured in the horse's hair were similar to those found in human and dog hair. When interpreting a result, it should be kept in mind that hair color, especially gray hair, influences the concentrations of some elements in horse hair.  相似文献   

5.
This work describes a new hair dyeing methodology using a chemical reaction between geniposide, an iridoid glycoside extracted from the fruit of Genipa americana (geniposide extract, GE) and the amine group of hair keratin. The influence of reaction conditions (pH, temperature, and extract concentration) on the staining of hair fibers, color development, fiber morphology, and mechanical hair properties of black and white human hair samples, was evaluated before and after GE dyeing treatment. Eye contact safety of GE was also studied using HET-CAM. The treatment of white hair fibers using GE at 20 mg mL−1, temperature of 80 °C and pH 5.5 presented the greatest color change (ΔE=54.0). The higher pH influence was observed at pH 10.0 on white hair tresses (ΔE=6.8), using an GE concentration of 20 mg mL−1 and room temperature (25 °C). Treated samples showed marked changes on mechanical and morphological properties. The HET-CAM did not show any change, thus demonstrating that using GE is safe. In conclusion, the temperature and concentration of the extract were the variables that mostly influenced the color and hair damage. A new approach for hair dyeing was established where iridoids may potentially be useful as a natural hair dyeing.  相似文献   

6.
The selenium (Se) content of the diet and/or selenium supplements might have an ameliorating effect on arsenic (As) toxicity as recently shown by Wang et al. (1), Yang et al. (2), and as reviewed by Spallholz et al. (3). The underlying principles of the ameliorating effect is the complexation of Se with As forming the seleno-bis (S-glutathionyl) arsinium ion (4) excreted in bile and the complexation of Se with As in tissues forming nontoxic insoluble selenides (5,6). Addition protection afforded by Se supplementation from arsenicosis could be the elevation of glutathione peroxidase activity reducing the oxidative stress induced by As (7,8). The present study assessed the status of Se and As in hair by neutron activation analysis (NAA). Human hair samples were collected from the United States, Canada, The People's Republic of China (PRC), Bangladesh, and Nepal, the latter two countries now engaged in a struggle to find relief from human arsenicosis resulting from extensive domestic groundwater contamination by As. No statistically significant differences were observed in the samples between the Se and As content of hair from, Lubbock, Texas (USA) or Winnipeg, Canada. The concentration of As in all hair samples analyzed correlated (r=0.960, p<0.001) with the amount of As in the drinking water. Selenium levels in hair were highest from Nepal. The results demonstrate the viability of hair as a noninvasive biomonitor in assessing aspects of dietary Se and environmental As exposure. The hair data confirmed the known low intake of Se in the Keshan disease area of the PRC, the very high accumulation in hair of As from subjects consuming contaminated ground waters, and an adequate Se status in subjects from North America consuming municipal water of low As content. The high As content of hair from people in Bangladesh is the result of a high As consumption from contaminated water compounded by a less than desirable intake of Se (9). From Nepal, the As content of hair corresponded to the known low and high intake of As from contaminated groundwater. The very high Se content found in all hair samples from Nepal might be the result of the use of henna.  相似文献   

7.
目的 头发是一类重要的皮肤附属物,主要由角蛋白和角蛋白相关蛋白等组成。不同种族及性别样本的头发蛋白质组成和占比存在差异,且目前缺乏高效率提取头发蛋白的方法。本文探究基于定量头发蛋白质组学方法,旨在探索该方法区分不同个体的可能性。方法 以3例头发样本,对样品处理方法和裂解缓冲液进行探究,发展一种名为PLEE (PTM lab for protein extraction from hair with high efficiency)的稳定、高效的头发蛋白质提取方法,对7例人发样本,以PLEE法进行提取,结合胶内消化方法进行蛋白质组学实验,产出蛋白质组学数据,分析个体间的头发蛋白质组成及占比。结果 共鉴定274种蛋白质,共有的蛋白质107种,非共有蛋白质种类在57~119,部分样本存在独特鉴定蛋白。使用共鉴定107种蛋白质进行定量蛋白质组分析,通过聚类和主成分分析,可将各样本进行区分,且技术重复样本可聚在一起,表明流程的稳定性。另外,筛选出10个关键蛋白(KRT33A、KRTAP9-6、KRT83、KRTAP7-1、KRT32、BLMH、KRT38、KRTAP11-1、NPAS1、KRTA...  相似文献   

8.
A mathematical method is described for using an amino acid analysis for estimating the proportions of the major structural components of human hair. Application of this method to the amino acid composition of hair from malnourished children and from trichothiodystrophic hair suggests its potential usefulness as a diagnostic index, particularly for nutritional status. The possible relevance of the results to the biosynthesis of hair proteins is also discussed.  相似文献   

9.
Selenium deficiency in yugoslavia   总被引:1,自引:0,他引:1  
Data on selenium (Se) deficiency in Yugoslavia are presented. The results include Se content of soil, cereal crops, and garlic grown in these soils, and human serum and scalp hair from several towns and regions. All data indicate a serious Se deficiency: soil (n=140), the mean value of 200±69.6 μg/kg Se; wheat, (58) = 20.5 ± 12.4 μg/kg; corn, (79) = 13.7 ± 13.6 μg/kg; and garlic, (66) = 13.7 ± 17.1 μg/kg Se. Analyses of human tissue show a very low Se status of the Yugoslav population: serum, (n=875) = 50.0 ± 18.0 μg/L and scalp hair, (388) = 94 ± 16 μg/kg Se. In some regions, Se contents of grain, garlic, and human serum and hair are approaching those in the low-Se belt in China. It is assumed that very low Se status of a human population could be a risk factor in the development of Balkan Endemic Nephropathy (BEN) and in a high incidence of urinary tract tumors (UTT) in endemic areas. A portion of these results were presented at the International Symposium on Selenium, Belgrade, May 12–15, 1991, Abstracts p.1, Serbian Academy of Sciences and Arts.  相似文献   

10.
Although we have made significant progress in understanding the regulation of the UVR‐exposed epidermal‐melanin unit, we know relatively little about how human hair follicle pigmentation is regulated. Progress has been hampered by gaps in our knowledge of the hair growth cycle’s controls, to which hair pigmentation appears tightly coupled. However, pigment cell researchers may have overly focused on the follicular melanocytes of the nocturnal and UVR‐shy mouse as a proxy for human epidermal melanocytes. Here, I emphasize the epidermis‐follicular melanocyte pluralism of human skin, as research models for vitiligo, alopecia areata and melanoma, personal care/cosmetics innovation. Further motivation could be in finding answers to why hair follicle and epidermal pigmentary units remain broadly distinct? Why melanomas tend to originate from epidermal rather than follicular melanocytes? Why multiple follicular melanocyte sub‐populations exist? Why follicular melanocytes are more sensitive to aging influences? In this perspective, I attempt to raise the status of the human hair follicle melanocyte and highlight some species‐specific issues involved which the general reader of the pigmentation literature (with its substantial mouse‐based data) may not fully appreciate.  相似文献   

11.
Objective: The objective of this study was to determine the effect of body hair (scalp and facial) on air displacement plethysmography (BOD POD) estimates of percentage of body fat. Research Methods and Procedures: A total of 25 men (31.4 ± 8.0 years, 83.4 ± 12.2 kg, 181.8 ± 6.9 cm) agreed to grow a beard for 3 weeks to participate in the study. Total body density (g/cm3) and percentage of body fat were evaluated by BOD POD. To observe the effect of trapped isothermal air in body hair, BOD POD measures were performed in four conditions: criterion method (the beard was shaven and a swimcap was worn), facial hair and swimcap, facial hair and no swimcap, and no facial hair and no swimcap. Results: The presence of only a beard (facial hair and swimcap) resulted in a significant underestimation of percentage of body fat (16.2%, 1.0618 g/cm3) vs. the criterion method (17.1%, 1.0597 g/cm3, p < 0.001). The effect of scalp hair (no swim cap worn) resulted in a significant underestimation in percentage of body fat relative to the criterion method, either with facial hair (facial hair and no swimcap; 14.8%, 1.0649 g/cm3) or without facial hair (no facial hair and no swimcap; 14.8%, 1.0650 g/cm3, p < 0.001 for both). Discussion: A significant underestimation of percentage of body fat was observed with the presence of facial hair (~1%) and scalp hair (~2.3%). This underestimation in percentage of body fat may be caused by the effect of trapped isothermal air in body hair on body‐volume estimates. Thus, excess facial hair should be kept to a minimum and a swimcap should be worn at all times to ensure accurate estimates of body fat when using the BOD POD.  相似文献   

12.
We used genetic and stable isotope analysis of hair from free-ranging black bears (Ursus americanus) in Yosemite National Park, California, USA to: 1) identify bears that consume human food, 2) estimate the diets of these bears, and 3) evaluate the Yosemite human–bear management program. Specifically, we analyzed the isotopic composition of hair from bears known a priori to be food-conditioned or non-food-conditioned and used these data to predict whether bears with an unknown management status were food-conditioned (FC) or non-food-conditioned (NFC). We used a stable isotope mixing model to estimate the proportional contribution of natural foods (plants and animals) versus human food in the diets of FC bears. We then used results from both analyses to evaluate proactive (population-level) and reactive (individual-level) human–bear management, and discussed new metrics to evaluate the overall human–bear management program in Yosemite. Our results indicated that 19 out of 145 (13%) unknown bears sampled from 2005 to 2007 were food-conditioned. The proportion of human food in the diets of known FC bears likely declined from 2001–2003 to 2005–2007, suggesting proactive management was successful in reducing the amount of human food available to bears. In contrast, reactive management was not successful in changing the management status of known FC bears to NFC bears, or in reducing the contribution of human food to the diets of FC bears. Nine known FC bears were recaptured on 14 occasions from 2001 to 2007; all bears were classified as FC during subsequent recaptures, and human–bear management did not reduce the amount of human food in the diets of FC bears. Based on our results, we suggest Yosemite continue implementing proactive human–bear management, reevaluate reactive management, and consider removing problem bears (those involved in repeated bear incidents) from the population. © 2012 The Wildlife Society.  相似文献   

13.
Hair, water, and sediment samples (n = 69, 27, and 24, respectively) were collected at four locations (P1–P4) along the Yellow River Gan-Ning-Meng (GNM) reaches, China. Total elemental contents of Cd, Cr, Cu, Fe, Mn, Pb, and Zn were determined using inductively coupled plasma mass spectroscopy (ICP-MS) to investigate their distribution and exposure levels in the different media. Results showed that trace metals had widely spatial variability in water and hair samples. There were the highest levels of mean concentrations of Cd, Cu, Fe, Mn, Pb, and Zn (geometric mean, GM = 0.22, 17, 65, 3.0, 4.9, and 170 μg/g, respectively) in residents' hairs living at P2. Most of the hair donors in this study showed high concentrations of Cr when compared with the literature. Differences could be distinguished for Mn (p = 0.001) and Fe (p = 0.001) with gender, and for Cr (p = 0.021), Zn (p = 0.003), and Pb (p = 0.035) with age, respectively. The pollution assessments revealed an unpolluted degree in filtered water and a moderately polluted degree for Cd in sediments at P1–P4. Correlation analysis showed significant correlations between hair and sediment samples for Cr and Mn. This paper provides basic and useful information in facing public and environmental health challenges in the GNM sections of the Yellow River.  相似文献   

14.
A recent trend in stable isotopic analysis involves the reconstruction of short-term variations in diet using hair segments. However, bulk hair samples typically contain a growth cycle error, which may conceal or confound the most recently incorporated isotopic information. It is assumed that, at any given time, ~85-90% of scalp hairs are actively growing, while the remaining 10-15% have transitioned into a resting or inactive phase, which lasts up to 4 months before hairs are shed. This study uses growth phase to determine the effects of age, sex, and health status on carbon and nitrogen isotopic ratios of hair analyzed in sequential segments. For this study, we selected archaeological hair samples from 10 individuals from Dakhleh Oasis, Egypt. Isotopic analyses of actively growing hair segments were compared to those for mixed growth phase segments from each individual. These data demonstrate the presence of growth cycle error and show that an understanding of structural-functional relationships is essential for interpreting normal versus pathological changes in hair follicle and fiber production. In situations where diet change and mobility produce variations in an individual's isotopic composition, elimination of positional-temporal error in sequential segment hair analyses can facilitate greater understanding of intraindividual metabolic reactions and changes in hair growth cycles. Phase identification may aid in determining the presence of pathological conditions in individuals, especially in those lacking skeletal indications, and provide a more precise estimation of seasonal dietary patterns, access to changing food resources, and metabolic equilibration to a new locality.  相似文献   

15.
Heavy metals in biological samples: nails, teeth, and hair were examined during 1991–1993. Investigations of biological samples (hairn=249 samples, teethn=145, nailsn=80 samples) were provided for inhabitants of selected towns in Beskid Śląski. The towns are small mountain towns in southern Poland: Wista, Szczyrk, Istebna, Koniaków, and Jaworzynka. The analysis of ANOVA and MANOVA variances were used for biological samples in the context of age, sex, and type of samples for 12 elements (Pb, Cd, Cr, Zn, Fe, Cu, Mn, Ni, Co, Ca, Na, and K). The matrix correlation and cluster analysis were applied to explain the behavior of metals in human hair, teeth, and nails.  相似文献   

16.
人类头发是以角蛋白和角蛋白相关蛋白为主要成分的天然纤维,是一种可表征一定时间内机体状态的良好生物学样本。头发易采集、低成本、易于运输和存储等优点使其在毒品、酒精及兴奋剂等的检测中具有独特优势。蛋白质组学是一种在整体水平上研究蛋白表达和调控的新兴技术,在生命科学领域应用广泛。蛋白质组学技术可用于不同人群头发蛋白组成及动态变化研究,在寻找疾病标志物、区分个人特质等方面具有巨大潜力。本文从头发的结构及组成、心理压力下头发的变化以及头发蛋白质组学分析技术的研究进展进行了全面综述,对理解头发蛋白质组学表征人体特征以及指导相关研究具有重要意义。  相似文献   

17.
Determination of inseparable exogenous and endogenous levels of toxic trace elements such as lead in human scalp hair has been used to understand and assess population exposure to such elements. For any such analysis, washing of the hair samples to remove superficial contamination is the foremost requirement. However, the use of such washing methods prior to elemental analysis removes minute quantities of trace elements from the hair strands. This degree of loss is dependent on the washing method employed. In the present study, the element lead has been determined in human scalp hair after three methods of hair washing. It is apparent that the nonionic detergent-acetone method is best suited for securing valid lead analysis results in human scalp hair.  相似文献   

18.
Genetic variation and population structure of hair crab (Erimacrus isenbeckii) were examined using nucleotide sequence analysis of 580 base pairs (bp) in the 3′ portion of the mitochondrial cytochrome c oxidase subunit I gene (COI) of 20 samples collected from 16 locales in Japan (the Hokkaido and Honshu Islands) and one in Korea. A total of 27 haplotypes was defined by 23 variable nucleotide sites in the examined COI region. Pairwise population F ST estimates and neighbor-joining tree inferred distinct genetic differentiation between the representative samples from the Pacific Ocean off the Eastern Hokkaido Island and the Sea of Japan, while others were intermediate between these two groups. AMOVA also showed a weak but significant differentiation among these three groups. The present results suggest a moderate population structure of hair crab, probably influenced by high gene flow between regional populations due to sea current dependent larval dispersal of this species.  相似文献   

19.
Low phosphorus availability stimulates root hair elongation in many plants, which may have adaptive significance in soil phosphorus acquisition. We investigated the effect of low phosphorus on the elongation of Arabidopsis thaliana root hairs. Arabidopsis thaliana plants were grown in plant culture containing high (1000 mmol m?3) or low (1 mmol m?3) phosphorus concentrations, and root hair elongation was analysed by image analysis. After 15d of growth, low-phosphorus plants developed root hairs averaging 0.9 mm in length while high-phosphorus plants of the same age developed root hairs averaging 0.3 mm in length. Increased root hair length in low-phosphorus plants was a result of both increased growth duration and increased growth rate. Root hair length decreased logarithmically in response to increasing phosphorus concentration. Local changes in phosphorus availability influenced root hair growth regardless of the phosphorus status of the plant. Low phosphorus stimulated root hair elongation in the hairless axr2 mutant, exogenously applied IAA stimulated root hair elongation in wild-type high-phosphorus plants and the auxin antagonist CM PA inhibited root hair elongation in low-phosphorus plants. These results indicate that auxin may be involved in the low-phosphorus response in root hairs.  相似文献   

20.
Melanin isolated from the ink sac of cuttle fish (Sepia melanin) is a proposed standard for natural eumelanin. Sepia melanin isolated by a standard protocol was submitted for both elemental analysis and quantitative amino acid analysis. The contribution of the detected amino acids to the elemental composition is subtracted from the total elemental analysis, and the resultant elemental composition reflects the composition of the Sepia melanin backbone chromophore. The assumption is made that, for eumelanins, there is only one nitrogen atom per monomeric unit, and thus, the empirical formula for the average monomeric Sepia melanin backbone chromophore was determined. Three key parameters can be determined for any melanin sample; namely, the molar C/N for the average monomeric unit, the formula weight of the average monomeric unit, and the total percent composition of amino acid residues. Three commonly used melanin preparations, namely, natural Sepia melanin, melanin prepared by the in vitro tyrosinase catalyzed polymerization of tyrosine (tyrosine-enzymatic melanin), and a polymer synthesized by the peroxide oxidative polymerization of tyrosine (tyrosine-chemical melanin), have been subjected to this standard method of characterization. Tyrosine-enzymatic and Sepia melanin are quite similar and tyrosine-chemical melanin is fundamentally different from the other two melanins.  相似文献   

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