In situ Chelation of Monoazo Dyes in Human Hair Keratin Fibers Using Environmentally Benign Metal Ions.

The coloration of human hair keratin fibers has long involved the oxidative coupling of primarily aromatic amines and phenols inside the fibers with the aid of harsh agents such as H2O2 and NH4OH. Further, the traditional process has exposed millions of consumers and their hairstylists to toxic substances such as skin sensitizers. While alternative hair dyeing processes have been explored, they fail to be competitive with the traditional method, for reasons including impracticality and limited colors achievable. In the present study, we developed an approach to imparting color to human hair fibers that involves entrapping colorants inside hair fibers by forming chelated monoazo dyes in situ. Dyes employed were based on monoarylide, arylazopyrazolone, and arylazonaphthol families, which display yellow, orange, and magenta colors on dyed hair. The dyes were applied at 40 °C without the use of oxidants and alkali associated with current commercial hair dyes, with the best dye uptake observed when the arylazonaphthol dye was employed. The dyed hair fibers showed good durability to washing, and treatment of these fibers with Al3+ or Fe3+ ions at 40 °C led to the rapid in situ formation of 1:2 metal/dye structures. In addition, the dyed hair was soft, indicating that chelated dye occupies the interior of the fibers rather than the surface. Such an approach can be applied to the coloration of other materials, including textiles.

A promising Ames battery for mutagenicity characterization of new dyes.

When testing new products, potential new products, or their impurities for genotoxicity in the Ames test, the quantity available for testing can be a limiting factor. This is the case for a dye repository of around 98,000 substances the Max Weaver Dye Library (MWDL). Mutagenicity data on dyes in the literature, although vast, in several cases is not reliable, compromising the performance of the in silico models. In this report, we propose a strategy for the generation of high-quality mutagenicity data for dyes using a minimum amount of sample. We evaluated 15 dyes from different chemical classes selected from 150 representative dyes of the MWDL. The purity and molecular confirmation of each dye were determined, and the microplate agar protocol (MPA) was used. Dyes were tested at the limit of solubility in single and concentration-response experiments using seven strains without and with metabolic activation except for anthraquinone dyes which were tested with eight strains. Six dyes were mutagenic. The most sensitive was YG1041, followed by TA97a > TA98 > TA100 = TA1538 > TA102. YG7108 as well as TA1537 did not detect any mutagenic response. We concluded that the MPA was successful in identifying the mutagenicity of dyes using less than 12.5 mg of sample. We propose that dyes should be tested in a tiered approach using YG1041 followed by TA97a, TA98, and TA100 in concentration-response experiments. This work provides additional information on the dye mutagenicity database available in the literature.

Data from X-ray crystallographic analysis and DFT calculations on isomeric azo disperse dyes.

X-ray crystallography and DFT calculations were used to characterize the molecular nature and excited state properties of isomeric photostable azo dyes for textile fibers undergoing extensive sunlight exposure. Structural data in CIF files arising from X-ray analysis are reported and the complete files are deposited with the Cambridge Crystallographic Data Centre as CCDC 1548989 (https://www.ccdc.cam.ac.uk/structures/Search?Ccdcid=1548989) and CCDC 1548990 (https://www.ccdc.cam.ac.uk/structures/Search?Ccdcid=1548990). Data from calculating the vertical electronic excitation of 20 excited states for each dye and from calculating excited state oxidation potential (ESOP) and Frontier HOMO/LUMO isosurfaces are also presented. This data is related to the article "Molecular and excited state properties of isomeric scarlet disperse dyes" (Lim et al., 2018) [1].

Weaver's historic accessible collection of synthetic dyes: a cheminformatics analysis.

We present the Max Weaver Dye Library, a collection of ∼98 000 vials of custom-made and largely sparingly water-soluble dyes. Two years ago, the Eastman Chemical Company donated the library to North Carolina State University. This unique collection of chemicals, housed in the College of Textiles, also includes tens of thousands of fabric samples dyed using some of the library's compounds. Although the collection lies at the core of hundreds of patented inventions, the overwhelming majority of this chemical treasure trove has never been published or shared outside of a small group of scientists. Thus, the goal of this donation was to make this chemical collection, and associated data, available to interested parties in the research community. To date, we have digitized a subset of 2700 dyes which allowed us to start the constitutional and structural analysis of the collection using cheminformatics approaches. Herein, we open the discussion regarding the research opportunities offered by this unique library.

Cerebral Metastases of Lung Cancer Mimicking Multiple Ischaemic Lesions - A Case Report and Review of Literature.

BACKGROUND: Restricted diffusion that is found on magnetic resonance diffusion-weighted imaging (DWI) typically indicates acute ischaemic stroke. However, restricted diffusion can also occur in other diseases, like metastatic brain tumours, which we describe in this case report. CASE REPORT: A 57-year-old male, with a diagnosis of small-cell cancer of the right lung (microcellular anaplastic carcinoma), was admitted with focal neurological symptoms. Initial brain MRI revealed multiple, disseminated lesions that were hyperintense on T2-weighted images and did not enhance after contrast administration; notably, some lesions manifested restricted diffusion on DWI images. Based on these findings, disseminated ischaemic lesions were diagnosed. On follow-up MRI that was performed after 2 weeks, we observed enlargement of the lesions; there were multiple, disseminated, sharply outlined, contrast-enhancing, oval foci with persistent restriction of diffusion. We diagnosed the lesions as disseminated brain metastases due to lung cancer. To our knowledge, this is the first description of a patient with brain metastases that were characterised by restricted diffusion and no contrast enhancement. CONCLUSIONS: Multiple, disseminated brain lesions, that are characterised by restricted diffusion on DWI, typically indicate acute or hyperacute ischemic infarcts; however, they can also be due to hypercellular metastases, even if no contrast enhancement is observed. This latter possibility should be considered particularly in patients with cancer.

Evaluation of pain in patients with lumbar disc surgery using VAS scale and quantitative sensory testing.

BACKGROUND: Pain is interpreted at the cortex level, however, pain signaling stimuli arise at the periphery and are conveyed by nociceptive A delta and C fibers. OBJECTIVES: Evaluation of pain using the VAS scale in pre- and postoperative S1 sciatica patients with regard to thermal thresholds in the corresponding dermatome. MATERIAL AND METHODS: Twenty-six S1 sciatica patients with herniated disc on an MRI, non-responsive to conservative care, were involved in the study. Pain in the affected leg was measured using the VAS scale and thermal thresholds in S1 symptomatic dermatome using Quantitative Sensory Testing (QST). RESULTS: Pain intensity as well as thermal thresholds were increased in sciatica patients compared to controls. Disc surgery resulted in a pronounced lowering of pain in each of the operated patients. From the whole group, 21 subjects were examined postoperatively six months later. In the group with complete clinical recovery, thermal thresholds were within normal limits. In those patients with residual pain disability, normalization of thresholds has not been achieved. CONCLUSIONS: Pain in sciatica patients may be objectively measured by QST.

[Thalidomide-induced sensory neuropaty in patients with multiple myeloma]. / Neuropatia czuciowa u chorych na szpiczaka mnogiego leczonych talidomidem.

UNLABELLED: Chemotherapy-induced sensory neuropathies differ in clinical picture. There is predominance of paresthesiae in some of them while in others pain or deep sensation failure can dominate. THE AIM OF THE STUDY: To perform the clinical and electrophysiological assessment of peripheral sensory nerves in patients with multiple myeloma (m.m.) treated with thalidomide. Special attention was directed to function of subtypes of sensory fibres which convey different modalities of sensation. MATERIAL AND METHODS: Twenty seven m.m. patients and 30 controls were examined. Neurological examination together with allocation to different groups acc. to sNCI-CTC scale were performed. Standard sensory conduction velocity was measured in ulnar and sural nerves. Quantitative Sensory Testing (QST) was used to determine thermal detection thresholds. RESULTS: All patients informed about subjective positive sensory symptoms and sensory deficit of symmetrical, distal pattern was found in them. Electroneurography revealed axonal and demyelinating abnormalities with dominance of axonal injury. Warm and heat-pain detection thresholds were elevated, while threshold for skin cooling was decreased both in palm and foot in m.m. patients in comparison with controls. There were no differences in the thresholds for cold-pain detection between examined groups. CONCLUSIONS: Thalidomide-induced sensory neuropathy can appear shortly after the introduction of treatment. Patients with longer duration of treatment or with higher cumulative dose present higher degree of neuropathy acc. to the sCNI-CTC scale. Sensory deficit in thalidomide' neuropathy is associated with dysfunction in A delta and C caliber primary afferent fibres.