Kinds Of Hairs Research Articles

Localization, morphology, anatomy and ultrastructure of osmophores in species of Rhamnaceae.

Although the presence of scent was described for several species of Rhamnaceae, localization, morphology and structure of osmophores were unknown. We studied different species of the tribes Rhamneae (Rhamnoids clade), Pomaderreae, Colletieae, Paliureae (Ziziphoids clade) and the species Alphitonia excelsa (unknown tribe, Ziziphoids clade). We expect to have a better comprehension of these structures and provide information on which morphological and anatomical characters may support the phylogeny of the family. We localized the osmophores in the margins and top of the sepals using neutral red. Histochemical tests were made on transverse hand-cut sections of fresh sepals. Observations were made with stereoscopic and bright field microscopes, scanning and transmission electron microscopes. Papillae were observed in the zones with positive reaction to reagents. Different kinds of hairs are present in the sepal epidermis besides papillae. Epidermal cells present a striate cuticle with canals and cavities. Druses are abundant in most species. The ultrastructure of epidermal and subepidermal cells shows high metabolic activity: there are vesicles, mitochondria, endoplasmic reticulum, dictyosomes, plastids with lipids and starch. The vascularization is well developed and reaches the top of the sepal where the principal area of volatile components production is localized. The location and abundance of papillae are the most important traits that allow us recognize and characterize the osmophores in Rhamnaceae. There are no clear anatomical and morphological features exclusive of one clade or tribe. Therefore, in contrast to other sporophytic structures of this family, osmophores do not seem to have any systematic value.

Top stories: A new kind of hair ‘ID,’ healing broken bird wings, and double dipping NIH researchers

Top stories: A new kind of hair ‘ID,’ healing broken bird wings, and double dipping NIH researchers

Bite Out Your Tongue

Bite Out Your Tongue

Do cosmetic treatments increase the incorporation of amphetamines into hair?

According to several studies, the concentration of drugs in hair may decrease by bleaching or dyeing; however, at the same time, treated hair could incorporate greater quantity of drugs from sweat or sebum than intact hair. The aim of this study is to assess the incorporation of amphetamine (AP), methamphetamine (MA) and 3,4-methylenedioxy-methamphetamine (MDMA) from sweat or sebum to virgin, dyed, and bleached hair. Drug-free head hair samples (from 20 volunteers) were divided into four locks, one of them was left untreated, another was subjected to dyeing treatment, and the last two were subjected to different degree of bleaching. Virgin, dyed, mildly as well as severely bleached locks of hair were exposed to artificial sweat or sebum containing AP, MA, and MDMA (500 ng/g), at 37 °C for a time period of 8 and 24 h, respectively. After the exposure, all the hair samples were tested by GC/MS in SIM mode, applying an already published method. Drug concentrations in hair ranged 0.41 to 2.20 ng/mg from artificial sweat, while only reached 0.27 ng/mg from artificial sebum. The differences of each drug concentration (AP, MA, MDMA) between different kind of hair were statistically compared: virgin hair vs. dyed hair, virgin hair vs mildly bleached hair, virgin hair vs. severely bleached hair. The differences between different drugs concentration within each kind of hair (virgin, dyed, mildly and severely bleached) were, as well, statistically compared: AP vs. MA, AP vs. MDMA, MA vs. MDMA. In all cases, differences were calculated between locks of hair from the same volunteer. The paired samples Student's t-test was applied in cases where the concentration differences followed the normal law. In these cases the extent of the difference was calculated with a confidence interval of 95%. The paired samples Wilcoxon's t -test was applied in cases where the concentration differences did not follow the normal law. Regarding the incorporation of AP, MA and MDMA from artificial sweat in vitro, the analysis provides evidence that the mean concentration for each drug in dyed or bleached hair is higher than the mean concentration in virgin hair, and that the differences between means are likely to be between 0.15 and 0.57 ng/mg, depending on the drug and the compared pairs. The incorporation of different drugs in the same kind of hair shows little differences in virgin and dyed hair, but the mean concentration of MDMA in bleached hair is higher than the mean concentration of AP; the differences between means are likely to be between 0.08 and 0.16 ng/mg. Regarding the incorporation of AP, MA and MDMA from artificial sebum in vitro, the differences between mean concentrations are lower for every compared pair, in relation to the incorporation from sweat. AP is not incorporated into hair from sweat or sebum to a greater extent than MDMA. Higher positivity rates for AP have been found in dyed or bleached hair in relation to virgin hair, detecting both significant [1] and non-significant [2] differences in the target populations. Based on these facts and the quantitative results of in vitro incorporation of amphetamine derivatives in hair, when interpreting the results from cosmetically treated hair, consideration should be given not only to the possibility that the treatment will lead to a decrease in drug concentration, but also to an increase. This consideration is particularly relevant if the detected levels are close to the cut-off.

Modulating hair follicle size with Wnt10b/DKK1 during hair regeneration.

Hair follicles have characteristic sizes corresponding to their cycle-specific stage. However, how the anagen hair follicle specifies its size remains elusive. Here, we showed that in response to prolonged ectopic Wnt10b-mediated β-catenin activation, regenerating anagen hair follicles grew larger in size. In particular, the hair bulb, dermal papilla and hair shaft became enlarged, while the formation of different hair types (Guard, Awl, Auchene and Zigzag) was unaffected. Interestingly, we found that the effect of exogenous WNT10b was mainly on Zigzag and less on the other kinds of hairs. We observed dramatically enhanced proliferation within the matrix, DP and hair shaft of the enlarged AdWnt10b-treated hair follicles compared with those of normal hair follicles at P98. Furthermore, expression of CD34, a specific hair stem cell marker, was increased in its number to the bulge region after AdWnt10b treatment. Ectopic expression of CD34 throughout the ORS region was also observed. Many CD34-positive hair stem cells were actively proliferating in AdWnt10b-induced hair follicles. Importantly, subsequent co-treatment with the Wnt inhibitor, DKK1, reduced hair follicle enlargement and decreased proliferation and ectopic localization of hair stem cells. Moreover, injection of DKK1 during early anagen significantly reduced the width of prospective hairs. Together, these findings strongly suggest that Wnt10b/DKK1 can modulate hair follicle size during hair regeneration.

Analysis of Hair Coat of Dachshund of Longhaired, Shorthaired, and Wirehaired Variety

Abstract The aim of the study was to analyse the hair coat of the three dachshund varieties, i.e. shorthaired, longhaired, and wirehaired, with respect to its histological structure and content of selected chemical elements. The study was conducted on female dachshunds originating from individual breeders. The study included the assessment of the contribution of particular hair fractions, measurements of hair thickness and length, and also the analysis of histological structure of particular hair fractions. A great differentiation in the parameters and structure of particular kinds of hair from the examined dogs was demonstrated. Thickness and length of hair of particular varieties showed statistically significant differentiation, as well as percentage contribution of particular hair fractions. As regard the content of chemical elements in particular hair fractions and dachshund variety, it appeared that the elements forming hair keratin were the most abundant. The findings presented in the paper may be a useful tool for the recognition of dachshund varieties based on their hair coat structure. They may be also a valuable contribution to the expanding breed standards, which lack histological hair description.

Classical Black

[A] water-smoothed head of antiquity brought up from the depths, intact; basalt blackness the concentration of time, not pigment. Even the hair – black man's kind of hair – had resisted water and remained classically in place as a seabird's feather or the lie of a fish's scales. (Gordimer 140)English in Africa Vol. 34 (2) 2007: pp. 19-34

A taxonomic Study of Lysimachia sect. Spicatae (Primulaceae) Based on Morphological Characters

The general morphological characters of Lysimchia sect. Spicatae were reviewed. From the results, numerical analyses were conducted based on 34 morphological characters from 14 populations of three species in Korea in order to investigate the key characters among the treated taxa and taxonomic delimitation and to discuss the systematic relationship. Habitat, leaf apices, presence or absent of hair on leaves, stipules, stems and bracts, branch of stems, kind of hair on floral axis and pedicels, shape of florescens were important diagnostic characters to identify the species. The relationship between Lysimachia clethoides and L. ba교stachys was more close than that of L. fortunei based on the quantitative characters. Also, a new key was made up from the result.

Relaxing/straightening of Afro‐ethnic hair: historical overview

Afro-ethnic hair, when compared with naturally straight hair, presents some important variations such as differences in diameter in many points of the thread, ellipsoidal threads, and low trend of hydrating the scalp thus turning the hair drier, because the natural sebum distribution is irregular along the thread. This kind of hair may be straightened through both chemical and thermal methods. Straightening is a chemical process by which excessively curly hair is straightened in an irreversible way. Generally, the products used are formulated in a cosmetic emulsion with high pH. In this review, we present the historical development of hair straightening or relaxing through the evolution of the product categories.

Rhodamine B as a collective marker for studying movements of small mammals

We present a new method of collective marking (rhodamine B) of small mammals that can be used under natural conditions. We examine the acceptance of marked baits, detection and persistence of the signal on the different kinds of hairs of two small species of rodents. Rhodamine B was ingested by captive animals and their hairs were dyed a fluorescent red coloration and observed over more than 150 days. Preliminary results obtained under field conditions tend to demonstrate that winter and summer movements could be detected by this technique. This new collective marking technique may be of great interest to study population turnover and movements of small mammals between habitat patches; it may represent an important method of assessing connectivity and permeability of landscapes by small mammals.

Concentrations of Potassium, Sodium, Magnesium, Calcium, Copper, Zinc, Manganese and Iron in Black and Gray Hairs in Taiwan

An investigation of the metal concentrations of potassium, sodium, calcium, magnesium, copper, zinc, manganese and iron in the black and gray hairs of the same person in Taiwan was performed using atomic absorption spectroscopy (AAS). The flame modus of AAS was employed to determine the concentrations of trace and mineral elements. The results of trace element and mineral element concentration determinations were evaluated by statistical analysis using the t-test for comparison of significant differences between black and gray hairs of the same person in the same region of the head. Our findings revealed that the concentrations of potassium, sodium, calcium, magnesium, copper, zinc, manganese and iron in gray hairs were lower than those in black hairs. Concentrations of manganese, copper, magnesium, calcium and sodium showed significant differences between the two kinds of hairs (p 0.05). Our experiment gives direct evidence to suggest that reduction of hair trace element and mineral element concentrations may be one of the factors associated with hair graying or aging. Manganese, copper, magnesium, calcium and sodium obviously have greater effects on the hair color and aging.

The genetic basis of patterned baldness in Drosophila

Norbert Perrimon Howard Hughes Medical Institute Department of Genetics Harvard Medical School Boston, Massachusetts 02115 Studies of segment polarity genes, which specify cellular identities within the Drosophila segmented embryonic epi- dermis, have identified two secreted proteins, wingless (wg) and hedgehog (hh), that play key roles in instructing cells about their fates within the segments. These mole- cules appear to function as signals in two temporally dis- tinct pathways. First, through short-range interactions, cells expressing the wg and hh signals stabilize their mu- tual expression. Second, these signals pattern cell types at a distance, acting either as morphogens or by the trig- gering of a cascade of local signaling responses and ulti- mately a determination of whether epidermal cells differ- entiate various kinds of hairs or naked cuticle. The functions of many other segment polarity genes can be explained either as regulators or transducers within the signaling pathways of these two primary signals. Wg and hh are also implicated in long-range signaling that estab- lishes cellular patterning within the imaginal discs. The components that mediate the wg and hh effects in both the embryo and imaginal discs are similar, indicating that these signals activate biochemical cascades that have been conserved between cell types. Identification of these molecules in vertebrates also suggests that these path- ways have been conserved during evolution. lntrasegmental patterning In the Drosophila embryo, the first morphological sign of segmentation begins at mid-stage 10 with the formation of metameric units or parasegments (Figure 1). The anterior boundaries of the pair rule genes fus/?Ctafazu and even-

Variability of opiates concentrations in human hair according to their anatomical origin: head, axillary and pubic regions

The concentrations of morphine and codeine were investigated in hair from the head, axillary and pubic regions obtained from 20 fatal heroin cases. Hair preparation involves decontamination procedure in dichloromethane at 37°C for 15 min, solubilization in sodium hydroxyde at 100°C for 5 min, neutralization with hydrochloric acid and centrifugation. After extraction in chloroform/isopropanol/ n-heptane (50:17:33; v/v) at pH 9.2, drugs were derivatized with BSTFA + 1% TMCS and separated on a 12-m BP-5 capillary column. Quantification was done by GC MS using selected ion monitoring. The highest morphine concentrations were found in pubic hair (0.80–41.34 ng/mg), followed by hair of the head (0.62–27.10 ng/mg), and axillary hair (0.40–24.20 ng/mg). Codeine was also detected in all samples, and the codeine/morphine ratios ranged from 0.054 to 0.273. The differences observed in drug concentration in the three kinds of hair are discussed in the light of the existing literature.

Etude en microscopie optique des poils (Pili) dela faune pyrénéene sauvage en vue de leur détermination

AbstractThis study presents certain data on the hairs of forty species of pyrenean mammals in order to recognize them in the faeces of wild carnivores. Six orders have been considered, in which there are 37 wild species and 3 domestic ones. Samples were taken from the skin of Regio dorsocostalis, on adult animals, and examined by optic microscopy.Different kinds of hairs and their constitutive parts were measured and observed, and a classification established in accordance with previous works. New Nomina Anatomica are proposed. Specific diagnosis of hairs is more or less easy according to the group to which they belong.

Observaciones sobre la epidermis foliar de Zea mays L. al microscopio electrónico de rastreo

Electron microscopic scanning of the adaxial leaf epidermis of Zea mays L. showed several kinds of hairs: macro-hairs on the veins, micro-hairs in the costal and intercostal zones and prickle hairs in the intercostal zones. Macro-hairs are lacking in the abaxial surface. The leaf is amphistomatic and stomata as well as short cells of various shapes (lenticular, crenate and tetralobulate) are restricted to the intercostal areas; the short cells form lines along the adaxial and abaxial (lower) intercostal zones as do the stomata in the abaxial surface. Small hollows of unknown origin and function, which alternate with the silica cells, are reported for the first time in this plant.The leaf sheath shows rectangular epidermal cells with linear cell walls in the intercostal zoneii; it is covered by a striated cuticle. Stomata are scarce and are morphologically similar to those of the blade. Silica cells of variable shape are present abaxially. Abaxial costal zones are similar to those of the abaxial leaf blade, although the leaf sheath is almost glabrous.