Compositional and Micro-Morphological Characterisation of Red Colourants in Archaeological Textiles from Pharaonic Egypt

When the imagination conjures up an image of an Egyptian mummy, it is normally one of a human body wrapped with undyed linen bandages. However, the reality was much more colourful, as shown by the set of red mummy shrouds and textile fragments from Pharaonic Egypt considered in this work. The textiles were subjected to scientific investigation with the main aim of shedding light on the sources of red colour and on the possible reasons for the different levels of colour fading. The red colourants were investigated using various non-invasive and micro-invasive approaches. The results pointed towards the presence of three sources of red colour, which, in increasing order of lightfastness, are safflower (Carthamus tinctorius), madder (Rubia spp.), and red ochre. Micro-morphological observations and elemental analyses also enabled some hypotheses to be formulated regarding the application of these colourants to the textiles. The results not only deepen our knowledge of dyeing technologies in ancient Egypt and shed new light on the function of red shrouds and textiles as part of the funerary practices of Pharaonic Egypt, but are also essential in planning the display and future preservation of these mummies and their associated textiles.

Medical Devices; General and Plastic Surgery Devices; Classification of the Internal Tissue Marker. Final order

The Food and Drug Administration (FDA) is classifying the internal tissue marker into class II (special controls). The special controls that will apply to the device are identified in this order and will be part of the codified language for the internal tissue marker's classification. The Agency is classifying the device into class II (special controls) in order to provide a reasonable assurance of safety and effectiveness of the device.

Grape stalks as substrate for white rot fungi, lignocellulolytic enzyme production and dye decolorization

The aim of this work was to evaluate the potential of grape stalks, an agroindustrial waste, for growth and lignocellulolytic enzyme production via solid-state fermentation, using the following three white rot fungi: Trametes trogii, Stereum hirsutum and Coriolus antarcticus. The decolorization of several dyes by the above mentioned cultures was also investigated. Similar values of dry weight loss of the substrate were measured after 60 days (33-43 %). C. antarcticus produced the highest laccase and Mn-peroxidase activities (33.0 and 1.6 U/g dry solid). The maximum endoglucanase production was measured in S. hirsutum cultures (10.4 U/g), while the endoxylanase peak corresponded to T. trogii (14.6 U/g). The C. antarcticus/grape stalk system seems potentially competitive in bioremediation of textile processing effluents, attaining percentages of decolorization of 93, 86, 82, 82, 77, and 58% for indigo carmine, malachite green, azure B, remazol brilliant blue R, crystal violet and xylidine, respectively, in 5 h.

Desorption of reactive dyes from modified chitin

A study was undertaken to evaluate the efficiency of adsorption and desorption of three reactive dyes on to modified chitin. Black DN from the chlorotriazine group, Scarlet R from the vinylsulfone group of dyes and a chlorovinyl dye, Brilliantorange 3R, were examined. Following adsorption of the dyes at pH 3, their desorption was carried out at pH 11. The results obtained indicated that the highest efficiency of desorption, nearly 100%, was obtained for Brilliantorange 3R, and lower ones for Scarlet R and Black DN, at 89% and 90%, respectively. The highest number of adsorption/desorption cycles, nearly 100, was recorded for Brilliantorange 3R. In the case of Scarlet R the number of subsequent adsorption/ desorption cycles run reached around 25, whereas in the case of Black DN it accounted for 37.

Toxicity of textile dyes and their degradation by the enzyme horseradish peroxidase (HRP)

The enzyme peroxidase is known for its capacity to remove phenolic compounds and aromatic amines from aqueous solutions and also to decolorize textile effluents. This study evaluates the potential of the enzyme horseradish peroxidase (HRP) in the decolorization of textile dyes and effluents. Some factors such as pH and the amount of H(2)O(2) and the enzyme were evaluated in order to determine the optimum conditions for the enzyme performance. For the dyes tested, the results indicated that the decolorization of the dye Remazol Turquoise Blue G 133% was approximately 59%, and 94% for the Lanaset Blue 2R; for the textile effluent, the decolorization was 52%. The tests for toxicity towards Daphnia magna showed that there was a reduction in toxicity after the enzymatic treatment. However, the toxicity of the textile effluent showed no change towards Artemia salina after the enzyme treatment. This study verifies the viability of the use of the enzyme horseradish peroxidase in the biodegradation of textile dyes.

[Observations on Acanthamoeba trophozoites in axenic cultures and their staining characteristics with different stains]

Acanthamoeba spp. are among the most prevalent protozoa found in the environment. The species of this genus are the causative agents of granulomatous amebic encephalitis (GAE), a fatal disease of the central nervous system (CNS), and amebic keratitis (AK), a painful sight-threatening disease of the eye. In this study we have used two species of Acanthamoeba, Acanthamoeba castellanii and A. hatchetti, both were obtained from Vienna, Austria. They were cultivated on non-nutritious agar seeded with Escherichia coli and PPYG (protease peptone-yeast extract-glucose) medium. Our aim was to concentrate on three points in relation to the trophozoites and cysts stages of these species as follows: (i) to observe their morphology, (ii). to confirm our previous observation of a canal between two trophozoites. The bridge-like connection between these trophozoites greatly resembled the one that can be observed in conjugation during an exchange of genetic material. Two tro-phozoites with a bridge-like extension between them keep their position for at least 200 minutes. (iii). to detect the reactions of trophozoites to various stains. According to our findings in regard to these three points: (i). trophozoites with more than one nucleus are often seen in axenic cultures. (ii). This resembles a type of conjugation with a transfer of genetic material between two trophozoites. Certainly, this needs further investigation using more sophisticated methods. (iii). trophozoites equally stained well with Heidenhain's iron haematoxylin, Giemsa, PAS, Masson Trichrome, and Toludin-O stains. However, our results with reticulin, PAP, Van Gison, Musicarmine and Orsein stains were not satisfactory.

Evaluation of the toxicity and teratogenity of six commercial textile dyes using the frog embryo teratogenesis assay-Xenopus

Potential developmental toxicities of six different textile dyes were evaluated using the frog embryo teratogenesis assay-Xenopus (FETAX). Xenopus laevis embryos were exposed to astrazon red FBL, astrazon blue FGRL, remazol red RR, remazol turquoise blue G-A, cibacron red FN-3G, and cibacron blue FN-R from stage 8 to 11 for a 96-h exposure period in static renewal test conditions. A minimum of 17 concentration-response tests were performed with tested dyes, excluding a control group for each dye. Median lethal concentration (LC50), malformation (EC50), non observed adverse effect concentration (NOAEC), and lowest observed adverse effect concentration (LOAEC) were calculated. Also, teratogenic index (TI), minimum concentration to inhibit growth (MCIG), and MCIG/LC50 values were determined for each of the tested dyes. Characteristic abnormalities induced by a given test material were determined by the relationship between concentration and dye in the study. Results from these studies suggested that each tested dye is teratogenic for X. laevis embryos. The lowest LC50 was determined for astrazon red exposure corresponding to a value of 4.73 mg/L. The LC50 value was similar for this dye and astrazon blue; the highest TI was calculated for astrazon blue exposure. Tests with X. laevis indicated that each of the tested compounds possessed teratogenic potential with varying degrees of potency: astrazon blue FGRL > remazol turquoise blue G-A > astrazon red FBL > cibacron blue FN-R > cibacron red FN-3G > remazol red RR. Different types of malformations occurred in the embryos, depending on concentration and dye. From these results, we can suggest that astrazon blue is the most toxic compound, but that the others are also highly toxic and teratogenic substances for X. laevis embryos. Results of the study confirmed that the FETAX assay can be useful in an integrated biological hazard assesment for the preliminary screening of textile dye stuff.

New tetrachromic VOF stain (Type III-G.S) for normal and pathological fish tissues

A new VOF Type III-G.S stain was applied to histological sections of different organs and tissues of healthy and pathological larvae, juvenile and adult fish species (Solea senegalensis; Sparus aurata; Diplodus sargo; Pagrus auriga; Argyrosomus regius and Halobatrachus didactylus). In comparison to the original Gutiérrez VOF stain, more acid dyes of contrasting colours and polychromatic/metachromatic properties were incorporated as essential constituents of the tetrachromic VOF stain. This facilitates the selective staining of different basic tissues and improves the morphological analysis of histochemical approaches of the cell components. The VOF Type III -6.5 stain is composed of a mixture of several dyes of varying size and molecular weight (Orange G<acid Fuchsin<Light green<Methyl Blue<Fast Green), which are used simultaneously, and it enables the individual tissues to be selectively differentiated and stained. Muscle fibers, collagen, reticulin and elastin fibers, erythrocytes, cartilage, bone, mucous cells, oocytes and larvae were selectively stained and differentiated. Dyes with small size and molecular weight (i.e Orange G), penetrate all tissue structures rapidly, but are only tightly retained in densely textured tissues (i.e erythrocytes). Methyl Blue is an interesting triarylmethane dye (large size and molecular weight), which is incorporated in this new VOF tetrachrome stain, and acquires histochemical significance when used at acid pH (2.8) because collagen and reticulin fibers, as well basophilic and metachromatic substances (strongly ionized sulphated glycoconjugates) can be identified. Muscle tissues show an evident green colour (Fast Green or Light Green affinities), even those isolated and/or diffuse muscle fibers present in the digestive submucosa layer. Connective tissues showed a specific and strong blue colour (Methyl Blue affinity) or mixed blue-red staining (Methyl Blue and Acid Fucshin affinities). Very noticeable is the staining of the mucous cells, as well as the hyaline capsule of the viral lymphocystic cells, which were stained blue-purple (carboxylated and/or strongly ionized sulphated groups). Cartilaginous tissues showed a blue or purple (Methyl Blue affinity) staining, and a specific red colour (Acid Fucshin affinity) was evident during calcification or in bone structures (i.e skeleton, fins, gills, teeth).

The natural constituents of historical textile dyes

The sources and structures of dyes used to colour Western historical textiles are described in this tutorial review. Most blue and purple colours were derived from indigo--obtained either from woad or from the indigo plant--though some other sources (e.g. shellfish and lichens) were used. Reds were often anthraquinone derivatives obtained from plants or insects. Yellows were almost always flavonoid derivatives obtained from a variety of plant species. Most other colours were produced by over-dyeing--e.g. greens were obtained by over-dyeing a blue with a yellow dye. Direct analysis of dyes isolated from artefacts allows comparison with the historical record.

White-rot fungi and their enzymes for the treatment of industrial dye effluents

White-rot fungi produce various isoforms of extracellular oxidases including laccase, Mn peroxidase and lignin peroxidase (LiP), which are involved in the degradation of lignin in their natural lignocellulosic substrates. This ligninolytic system of white-rot fungi (WRF) is directly involved in the degradation of various xenobiotic compounds and dyes. This review summarizes the state of the art in the research and prospective use of WRF and their enzymes (lignin-modifying enzymes, LME) for the treatment of industrial effluents, particularly dye containing effluents. The textile industry, by far the most avid user of synthetic dyes, is in need of ecoefficient solutions for its colored effluents. The decolorization and detoxification potential of WRF can be harnessed thanks to emerging knowledge of the physiology of these organisms as well as of the biocatalysis and stability characteristics of their enzymes. This knowledge will need to be transformed into reliable and robust waste treatment processes.

Evaluation of biotoxicity of textile dyes using two bioassays

The toxicity of eight textile dyes was evaluated using two bioassays namely: Ames test and seed germination test. The Ames test is widely used for the evaluation of hazardous mutagenic effect of different chemicals, as a short-term screening test for environmental impact assessment. The eight-textile dyes and Eithidium bromide dye (as positive control) were tested with five "his" Salmonella typhimurium strains: TA 100; TA 98; TA 1535; TA 1537; TA 1538. Using six concentrations of each dye (2.5 microg/ml, 4.5 microg/ml, 9 microg/ml, 13.5 microg/ml, 18 microg/ml, and 22.5 microg/ml) revealed that, most of the dyes were mutagenic for the test strains used in this study. The high concentrations of dye eliminated microbial colonies due to the high frequency of mutation causing lethal effect on the cells. In this work the phytotoxicity of different soluble textile dyes was estimated by measuring the relative changes in seed germination of four plants: clover, wheat, tomato and lettuce. The changes in shooting percentages and root length as affected by dye were also measured. Seed germination percent and shoot growth as well as root length were recorded after 6 days of exposure to different concentrations of textile dyes in irrigation water. The results show that high concentrations of dyes were more toxic to seed germination as compared with the lower concentrations. However, the low concentrations of the tested dyes adversely affected the shooting percent significantly.

Classification and naming of dyes, stains and fluorochromes

A classification of dyes and other colorants is proposed, based on the chemical features responsible for their visibility and generally consonant with the writings of modern color chemists. The scheme differs in several respects from that of the Colour Index (CI), but it retains some traditional small groups of dyes that include biological stains. Natural dyes, recognized as a group in the CI, are placed with or near synthetic dyes with identical or similar chromophores. The new scheme also provides categories for dyes and fluorochromes that do not have places in the CI classification. Some CI categories, including lactones, aminoketones and hydroxyketones, are not recognized in this new scheme, which is adopted in the forthcoming 10th edition of Conn's Biological Stains: a Handbook of Dyes and Fluorochromes for Use in Biology and Medicine. Some rules are also set out for the spelling of trivial names, which has long been inconsistent in scientific literature. The ending '-ine' is used for compounds derived from organic bases (e.g., fuchsine and thionine, not fuchsin or thionin), and names ending in '-in' are for compounds that are not bases or their derivatives (e.g., eosin and phloxin, not eosine or phloxine). Initial capital letters are used only for words that are names of people or places (e.g., Nile blue or Congo red) and for the 'generic' components of CI application names (as in Acid yellow 36). Other words, including trade names that have fallen into common usage are not capitalized (e.g., alcian blue, biebrich scarlet, coomassie blue). The recommended spellings of some dyes differ from those commonly seen in vendors' catalogs and in biological publications, but they are generally consistent with English and American dictionaries, with recent writings in English by color chemists, and with the trivial names of other organic compounds.

Q-switch laser and tattoo pigments: first results of the chemical and photophysical analysis of 41 compounds

BACKGROUND AND OBJECTIVE

In the Western world, there are at least 20-30 million people with tattoos. Improved self-image and social stigmatization are the main reasons for removing tattoos from skin. Q-switched lasers are applied to destroy the tattoo compounds in the skin. The treatment of tattoos containing ink often gives excellent results, whereas the results of treatments for coloured tattoos are not predictable and usually are worse. The chemical structure and the absorption spectra of the tattoo pigments are usually unknown. However, the efficacy of the treatment by using light of different Q-switched lasers (wavelengths 510, 532, 694, 755, 1064 nm) is correlated to both the chemical structure of the tattooed compounds yielding specific absorption spectra and the laser wavelength used.

STUDY DESIGN/MATERIALS AND METHODS

A structural and spectroscopic analysis of 41 coloured pigments was performed.

RESULTS

The 41 substances were identified, and they consist of 16 individual chemicals of different structured well-known industrial organic pigments. The absorption spectra of the 16 pigments were measured quantitatively.

CONCLUSION

The results of the present analysis explain to some extent the outcome of clinical studies regarding laser therapy of coloured tattoos. Because the laser energy used produces a high temperature in the azo or polycyclic pigments, it is necessary to investigate whether that change causes possibly toxic or cancerogenic compounds.

Endoscopic diagnosis of mucosal cancer

Now that minimally invasive treatment is performed more widely, it is important that more cases indicated for such treatment are diagnosed, i.e., microcancers that can be treated endoscopically should be accurately diagnosed. Since the diameter of early gastric cancer indicated for endoscopic treatment is generally less than 2.0 cm, detection of these microcancers is crucial and improvement in the endoscopic diagnosis is needed. We discuss the method for measuring lesion size, the procedure of dye scattering endoscopy, and the types of dyes used in this examination. In addition, we describe a method for increasing the diagnostic accuracy in the color of the vasoconstriction by the spraying of a drug that acts directly on the capillaries in the gastric mucosa. These basic aspects of endoscopic diagnosis of early gastric cancer will significantly assist gastroenterologists. We hope that these skills will be mastered and that endoscopic diagnosis, built on a firm foundation, will become even more widespread.

A new case of occupational asthma from reactive dyes with severe anaphylactic response to the specific challenge

A case of occupational asthma in a wool and cotton dyer handling reactive dyes is described. The patient was skin positive, but asymptomatic to house dust mites. A bromoacrilamidic dye (Lanasol Yellow 4G) has been identified through chamber inhalation challenge as being responsible for the sensitization. A very short (4-minute) exposure produced a severe immediate obstructive ventilatory defect followed by arterial hypotension and urticaria. Bronchial hyperresponsiveness as tested through metacholine challenge was absent both in basal conditions and after the dye challenge. Both prick and patch test for the dye were positive in the absence of any sign of contact dermatitis.