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1.
The hair of 132 healthy subjects between 6 and 40 yr old living in the Veneto region in Italy was analyzed by means of HPLC method in order to determine the presence of zinc, copper, nickel, manganese, and lead. The collected samples were subdivided on the basis of age (6–11 and 19–40 yr), and sex and color (black, red, brown, and blond). From the data some evident differences were emphasized. In female hair the content of metals was higher than in male hair independently of color. Blond hair gave the lowest concentration values of the elements studied independently of sex. The maximum amount of the metals was found generally in black hair, followed by red and brown hair. Age seems to have a different influence, with the copper element decreasing appreciably in brown and blond female hair as the age of the subjects increased.  相似文献   

2.
Hair examinations and comparisons conducted by forensic scientists often provide investigative and associative information. Apart from its length and its natural color, hair displays a morphologic diversity both macroscopically and microscopically. Pseudogenization of 相似文献   

3.
贵州布依族、仫佬族和毛南族9对遗传性状的基因频率   总被引:1,自引:0,他引:1  
对贵州布依族、仫佬族和毛南族1239例的9对遗传性状的基因频率进行了调查, 并对民族间基因频率差异进行显著性检验。结果显示: 卷舌和小指弯曲的显性基因频率高于隐性基因频率, 而叠舌、前额发际、发旋、耵聍、拇指类型、中指毛、环食指长则相反; 卷舌、叠舌、前额发际、耵聍、拇指类型、环食指长的基因频率在民族间差异较大, 而发旋、中指毛、小指弯曲则相对较小。  相似文献   

4.
In the light, transfer of lettuce seedlings precultured on liquid medium at pH 6.0 to fresh medium at pH 4.0 induces root hair formation. However, no root hairs form in the dark. Here, we investigated how light induces root hair formation. Randomization of the transverse cortical microtubule (CMT) arrays which occurs in root epidermal cells in the light prior to root hair initiation was not observed in the dark. However, addition of indole-3-acetic acid (IAA) or 1-aminocyclopropane-1-carboxylic acid (ACC) induced CMT randomization and root hair formation. In these cases, CMT randomization occurred in almost the same time-dependent manner as under light. However, root hair initiation was delayed for several hours in the dark. These results suggest that light promotes CMT randomization and root hair initiation via auxin and ethylene signaling but light additionally influences root hair initiation independently of these signaling mechanisms. Furthermore, addition of a microtubule-depolymerizing drug in the dark disrupted the transverse CMT arrays and initiated root hair formation; however, root hair elongation was still suppressed. Root hairs elongated when IAA or ACC was applied with the drug. These results suggest that light also promotes root hair elongation via auxin and ethylene signaling.  相似文献   

5.
Although Wnts are expressed in hair follicles throughout life from embryo to adult, and considered to be critical for their development and maturation, their roles remain largely unknown. In the present study, we investigated the effects of Wnts (Wnt-3a, Wnt-5a, Wnt-10b, and Wnt-11) on epithelial cell differentiation using adult mouse-derived primary skin epithelial cell (MPSEC) cultures and hair growth using hair follicle organ cultures. Only Wnt-10b showed evident promotion of epithelial cell differentiation and hair shaft growth, in contrast to Wnt-3a, 5a, and 11. Our results suggest that Wnt-10b is unique and plays an important role in differentiation of epithelial cells in the hair follicle.  相似文献   

6.
A method is described for the simultaneous identification and quantification of opiates, amphetamines, cocainics, diazepam and nordiazepam from one hair extract (typically 10-50mg hair). After decontamination by washing with shampoo, dichloromethane, isopropanol and acetone, drugs were extracted using 0.1M HCl followed by SPE clean-up using mixed-mode extraction cartridges. The SPE extracts were submitted to a two-step derivatisation using MBTFA and MSTFA+1% TCMS and analysis was performed by GC-MS using both SIM and scan modes. Four deuterated standards were used to monitor 14 compounds. The limit of quantification was the total drug detected from the sample. This was 5 ng for amphetamines and 10 ng for remaining drugs which is equivalent to 0.1 and 0.2 ng/mg from a 50mg sample. Standard curves for the range 5-400 ng total drug concentration for all drugs had regression coefficients greater than 0.98. An authentic hair sample was used to validate the method and gave R.S.D.s <25% for both inter and intra-day reproducibility. The results of the analysis of hair taken from four patients attending a drug treatment clinic and six hair samples including head hair, pubic hair, axial hair and beard taken at post-mortem are presented.  相似文献   

7.
Pituitary dwarfism (hGHD) is known to be associated with trace element deficiency, which causes improper functioning of the involved endocrine system. Previously, we reported on the head hair concentrations of zinc, copper, manganese, and iron from a total of 418 normal subjects (154 male and 264 female). In this report, we analyzed the head hair concentrations of the same four trace metals of 103 hGHD children (60 male and 43 female) under treatment with human growth hormone (hGH). These subjects ranged in age from 5 to 18 yr. The results were compared with 338 agematched normal subjects (120 male and 218 female). Both male and female hGHD showed approx 1.7 times higher zinc concentrations than normal subjects. Cheruvanky et al. reported a similar trend but with a slightly lower difference between hGHD and normal subjects. The average copper content in the hair of both male and female subjects also showed higher values for the hGHD than for the normal subjects, a trend similar to the values reported by Teraoka et al. In the case of manganese, the concentrations in hair of the hGHD were approx 50% of the values in the normal subjects. Head hair concentrations of iron in the hGHD were commensurate with the normal subjects. Because the content of trace elements in hair varies with the age of subjects, as a control, we investigated the head hair concentration of zinc from 20 healthy girls ranging in age from 10 to 18 yr. The average zinc concentration decreased from 10 to 12 yr, but no clear relation to age was observed from 13 yr and older. These trends were similar to our previous report. The zinc concentration in hair and body weight gain over a year was negatively correlated. The age variation in the content of zinc, copper, manganese, and iron in hair was measured comparing hGHD with the normal subjects in various ages. Concerning the zinc-level variation of hGHD and normal subjects, there were conspicuous differences between hGHD and normal subjects. For copper, the variations in concentration with age were similar to zinc. Regarding the age variations for manganese, hGHD had lower concentrations in hair compared to the normal subjects throughout adolescence (11–18 yr). We have studied the effects between the hair and these trace element concentrations in hGHD before and after hGH administration. These results suggest that hGH affects the metabolism of these trace elements.  相似文献   

8.
The relationships between metal contents in soil, road dust, and rice, and in human hair from a rural area of China were observed for Cr, Cu, Mn, Ni, Pb, and Zn. The results showed that the mean concentrations of Mn in human hair were higher than the highest reference value. The concentrations of Cr, Cu, Ni, and Zn in soil and road dust were usually higher than their background values. The enrichment factors indicated that the determined metals in soil and road dust were usually derived from natural sources. Chromium, Pb, and Zn in soils and road dusts from several sites were slightly influenced by anthropogenic sources. The regression analyses showed that positive relationships usually exist between the concentrations of the determined metals in rice and in human hair as well as in soil and in human hair. However, relationships between metal concentrations in road dust and in human hair were less obvious. The study demonstrated that human hair was an applicable biomonitor of metal concentrations in rice, soil, and road dust from a rural area in China. Metal concentrations in local human hair could be used to predict contamination levels of metals in rice and soil.  相似文献   

9.
We screened for genes specifically expressed in the mesenchymes of developing hair follicles using representational differential analysis; one gene identified was MAEG, which encodes a protein consisting of five EGF-like repeats, a linker segment containing a cell-adhesive Arg-Gly-Asp (RGD) motif, and a MAM domain. Immunohistochemistry showed that MAEG protein was localized at the basement membrane of embryonic skin and developing hair follicles, while MAEG expression diminished at the tip of the hair bud. A recombinant MAEG fragment containing the RGD motif was active in mediating adhesion of keratinocytes to the substratum in an RGD-dependent manner. One of the adhesion receptors recognizing the RGD motif was found to be the alpha8beta1 integrin, the expression of which was detected in the placode close to MAEG-positive mesenchymal cells, but later became restricted to the tip of the developing hair bud. Given its localized expression at the basement membrane in developing hair follicles and the RGD-dependent cell-adhesive activity, MAEG may play a role as a mediator regulating epithelial-mesenchymal interaction through binding to RGD-binding integrins including alpha8beta1 during hair follicle development.  相似文献   

10.
A cross-sectional sample of 3136 scalp hair drawn from 392 individuals aged 10 to 60 years and belonging to the Bania (n = 201) and Brahmin (n = 191) caste groups of Punjab State of India were examined for diameters of hair shaft and medulla, scale count, medulla type, hair index, medullary index and scale-count index, employing standard procedures. The mean hair shaft diameter, medullary diameter, incidence of medullation and scale-count index was higher in males, while the mean scale count was higher in females. However, with a few exceptions, the gender differences were not statistically significant (p < 0.05). The Brahmins showed significantly (p < 0.05) higher mean values of hair shaft diameter and scale count than the Banias. The mean scale-count index was higher among the Banias. The fragmentary medulla was the most common medullary type among the Banias, while the continuous medulla was the most frequent type of medulla among the Brahmins. The frequency of medullation was significantly more among the Banias. On the average, the hair shaft diameter and diameter of medulla increased up to 30 years. Some age variations in medullation were noticed in both the caste groups. No clear age trend was noticeable in the scale count. By and large, the mean hair shaft diameter of the Banias was less than that of other populations. The mean hair shaft diameter of the Brahmin males was greater than that of the Banias, the Onges, and the Bengalees. The Brahmin females showed greater mean hair shaft diameter than that of the Banias, the Australian Aborigines, the Juangs and the Onges. Human scalp hair shows some age, gender and population variations in micro-morphological variables which have the potential of being useful for anthropological and forensic investigations.  相似文献   

11.
Kim CM  Park SH  Je BI  Park SH  Park SJ  Piao HL  Eun MY  Dolan L  Han CD 《Plant physiology》2007,143(3):1220-1230
Root hairs are long tubular outgrowths that form on the surface of specialized epidermal cells. They are required for nutrient and water uptake and interact with the soil microflora. Here we show that the Oryza sativa cellulose synthase-like D1 (OsCSLD1) gene is required for root hair development, as rice (Oryza sativa) mutants that lack OsCSLD1 function develop abnormal root hairs. In these mutants, while hair development is initiated normally, the hairs elongate less than the wild-type hairs and they have kinks and swellings along their length. Because the csld1 mutants develop the same density and number of root hairs along their seminal root as the wild-type plants, we propose that OsCSLD1 function is required for hair elongation but not initiation. Both gene trap expression pattern and in situ hybridization analyses indicate that OsCSLD1 is expressed in only root hair cells. Furthermore, OsCSLD1 is the only member of the four rice CSLD genes that shows root-specific expression. Given that the Arabidopsis (Arabidopsis thaliana) gene KOJAK/AtCSLD3 is required for root hair elongation and is expressed in the root hair, it appears that OsCSLD1 may be the functional ortholog of KOJAK/AtCSLD3 and that these two genes represent the root hair-specific members of this family of proteins. Thus, at least part of the mechanism of root hair morphogenesis in Arabidopsis is conserved in rice.  相似文献   

12.
Goodrich LV 《Neuron》2005,45(1):3-5
Our senses of hearing and balance rely on the function of specialized receptor neurons called "hair cells." In this issue of Neuron, Grant et al. report a series of elegant zebrafish experiments that reveal a previously unappreciated role for glia in the regulation of hair cell proliferation and differentiation. This work is a beautiful example of how zebrafish are particularly useful model systems for studying hair cell development and function.  相似文献   

13.
Acute promyelocytic leukaemia (APL) is a distinctive subtype of acute myeloid leukaemias. Even through this human disease can be treated by the intravenous administration of all-trans retinoic acid (ATRA), 25% of patients typically relapse after the first treatment. In this context, the intravenous administration of APL patients with an aqueous solution of arsenic trioxide has also been demonstrated to be successful despite the established mammalian toxicity of this arsenic compound. Accordingly, the administration of a therapeutic dose of arsenic trioxide has resulted in an improved patient survival in both relapsing as well newly diagnosed APL patients.We present here a mini-review of the medicinal use of arsenite, its mammalian metabolism (with an emphasis on biomethylation pathways), its elimination and pharmacokinetics and the novel application of hair analysis as a biomonitoring material. This mini-review also introduces our own results on the analysis of hair of patients receiving arsenic trioxide therapy.In this work, instead of quantifying arsenic content in bulk hair, we performed longitudinal analysis in order to use hair as a marker of arsenic exposure correlated to a time scale. Taking into account the hair growth rate, the longitudinal analysis of hair is demonstrated to provide a chronological record of the treatment of patients with arsenic trioxide. The small quantity of material to be analysed required the use of Synchrotron radiation based X-ray fluorescence (SXRF) spectroscopy. The hair arsenic content was well correlated with the clinical background of patients and reflected the intake of arsenic trioxide. In particular, the onset of arsenic trioxide therapy and interruptions during therapy were reflected by total arsenic content, which suggested rapid elimination.Another type of experiment, micro-XRF cartography on thin hair slices, allowed us to obtain distribution maps of arsenic, which demonstrated that arsenic is located at the periphery of hair. Micro-XANES spectra recorded at the periphery of hair, suggest that inorganic arsenic is incorporated in hair in its trivalent oxidation state, in agreement with previous results.  相似文献   

14.
Sox2 has been variously implicated in maintenance of pluripotent stem cells or, alternatively, early stages of cell differentiation, depending on context. In the developing inner ear, Sox2 initially marks all cells in the nascent sensory epithelium and, in mouse, is required for sensory epithelium formation. Sox2 is eventually downregulated in hair cells but is maintained in support cells, the functional significance of which is unknown. Here we describe regulation and function of sox2 in the zebrafish inner ear. Expression of sox2 begins after the onset of sensory epithelium development and is regulated by Atoh1a/b, Fgf and Notch. Knockdown of sox2 does not prevent hair cell production, but the rate of accumulation is reduced due to sporadic death of differentiated hair cells. We next tested the capacity for hair cell regeneration following laser ablation of mature brn3c:gfp-labeled hair cells. In control embryos, regeneration of lost hair cells begins by 12 h post-ablation and involves transdifferentiation of support cells rather than asymmetric cell division. In contrast, regeneration does not occur in sox2-depleted embryos. These data show that zebrafish sox2 is required for hair cell survival, as well as for transdifferentiation of support cells into hair cells during regeneration.  相似文献   

15.
16.
In this investigation, the concentration levels of hair elements of calcium, iron, and zinc were measured in pregnant women from Tianjin metropolis, China. The subjects were 93 cases of pregnant women who had been suffering from calcium, iron, or zinc deficiency judged by blood tests at the mid-term of the second trimester or early in the third trimester. Of these 93 cases, 82 subjects had their hair element levels measured when the blood tests were conducted. Then, they were supplied with mineral element nutrients of gluconic acidic zinc (noted as Zn-nutrient), gluconic acidic calcium (Ca-nutrient), or/and ferrous sulfate (Fe-nutrient) which were correspondent to the deficient element(s) for more than 2 mo before 84 subjects returned to hospital for further diagnoses and had their hair element levels measured for the second time. Finally, in the third trimester or nearparturient phase, 13 subjects had their hair element levels measured again. Except for the deficiencies of calcium, iron, or/and zinc, these subjects were all healthy without symptoms of any diseases. The concentrations of hair Ca, Fe, and Zn were measured by X-ray fluorescence (XRF) spectrometry. These concentrations of the three hair elements measured at three different times were statistically analyzed. From the analyses, it was clear that hair concentrations of Ca, Fe, and Zn could reflect the effects of supplementation. Also, the mutual resistant effects among Ca-, Fe-, and Zn-nutrients were revealed. However, by appropriate combination, the mutual resistant effects could be depressed and mutual promotional effects might be enhanced. Finally, it could be concluded that mineral element deficiencies might be convalesced by adequate compensations of mineral element nutrients.  相似文献   

17.
As part of an ongoing research program on the development of drug detection methodology, we developed an assay for the simultaneous measurement of cocaine, heroin and metabolites in plasma, saliva, urine and hair by solid-phase extraction (SPE) and gas chromatography—mass spectrometry (GC—MS). The analytes that could be measured by this assay were the following: anhydroecgonine methyl ester; ecgonine methyl ester; ecgonine ethyl ester; cocaine; cocaethylene; benzoylecgonine; cocaethylene; norcocaethylene; benzoylnorecgonine; codeine; morphine; norcodeine; 6-acetylmorphine; normorphine; and heroin. Liquid specimens were diluted, filtered and then extracted by SPE. Additional handling steps were necessary for the analysis of hair samples. An initial wash procedure was utilized to remove surface contaminants. Washed hair samples were extracted with methanol overnight at 40°C. Both wash and extract fractions were collected, evaporated and purified by SPE. All extracts were evaporated, derivatized with N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) with 1% trimethylchlorosilane (TMCS) and analyzed by GC—MS. The limit of detection (LOD) for cocaine, heroin and metabolites in biological specimens was approximately 1 ng/ml with the exception of norcodeine, normorphine and benzoylnorecgonine (LOD = 5 ng/ml). The LOD for cocaine, heroin and metabolites in hair was approximately 0.1 ng/mg of hair with the exception of norcodeine (LOD = 0.3 ng/mg) and normorphine and benzoylnorecgonine (LOD = 0.5 ng/mg). Coefficients of variation ranged from 3 to 26.5% in the hair assay. This assay has been successfully utilized in research on the disposition of cocaine, heroin and metabolites in hair, plasma, saliva and urine and in treatment studies.  相似文献   

18.
Aml1/Runx1 controls developmental aspects of several tissues, is a master regulator of blood stem cells, and plays a role in leukemia. However, it is unclear whether it functions in tissue stem cells other than blood. Here, we have investigated the role of Runx1 in mouse hair follicle stem cells by conditional ablation in epithelial cells. Runx1 disruption affects hair follicle stem cell activation, but not their maintenance, proliferation or differentiation potential. Adult mutant mice exhibit impaired de novo production of hair shafts and all temporary hair cell lineages, owing to a prolonged quiescent phase of the first hair cycle. The lag of stem cell activity is reversed by skin injury. Our work suggests a degree of functional overlap in Runx1 regulation of blood and hair follicle stem cells at an equivalent time point in the development of these two tissues.  相似文献   

19.
Hair follicles are easily accessible skin appendages that protect against cold and potential injuries. Hair follicles contain various pools of stem cells, such as epithelial, melanocyte, and mesenchymal stem cells (MSCs) that continuously self-renew, differentiate, regulate hair growth, and maintain skin homeostasis. Recently, MSCs derived from the dermal papilla or dermal sheath of the human hair follicle have received attention because of their accessibility and broad differentiation potential. In this review, we describe the applications of human hair follicle-derived MSCs (hHF-MSCs) in tissue engineering and regenerative medicine. We have described protocols for isolating hHF-MSCs from human hair follicles and their culture condition in detail. We also summarize strategies for maintaining hHF-MSCs in a highly proliferative but undifferentiated state after repeated in vitro passages, including supplementation of growth factors, 3D suspension culture technology, and 3D aggregates of MSCs. In addition, we report the potential of hHF-MSCs in obtaining induced smooth muscle cells and tissue-engineered blood vessels, regenerated hair follicles, induced red blood cells, and induced pluripotent stem cells. In summary, the abundance, convenient accessibility, and broad differentiation potential make hHF-MSCs an ideal seed cell source of regenerative medical and cell therapy.  相似文献   

20.

Background  

This paper assess the relationship between the quantity of three anti-seizure medications in hair and the color of the analyzed hair, while controlling for the effects of dose, dose duration, and patient age for 140 clinical patients undergoing anti-seizure therapy. Three drugs are assessed: carbamazepine (40 patients), valproic acid (40 patients), and phenytoin (60 patients). The relationship between hair assay results, hair color, dose, dose duration, and age is modeled using an analysis of covariance. The covariance model posits the hair assay results as the dependent variable, the hair color as the qualitative categorical independent variable, and dose, dose duration, and age as covariates. The null hypothesis assessed is that there is a no relationship between hair color and the quantity of analyte determined by hair assay such that darker colored hair will demonstrate higher concentrations of analyte than lighter colored hair.  相似文献   

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