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Concept: Coal tar


Abstract The Goeckerman regimen, consisting of the application of crude coal tar combined with exposure to ultraviolet radiation, was formulated in 1925 for the treatment of psoriasis. While some centers have adapted the Goeckerman regimen for the treatment of eczema, there are no published reports of its efficacy in this condition. Here, we explain how the Goeckerman regimen has been modified for use in an eczema population at the University of California San Francisco (UCSF). We reviewed the treatment records of eczema patients treated with the modified Goeckerman regimen over a 6-year period at UCSF. We found that the Goeckerman regimen was effective in treating patients with severe baseline disease, inducing a mean remission period of 7.2 months. The treatment was tolerated well with mild folliculitis and occasional ultraviolet B phototoxicity noted as the only adverse reactions. Since the use of Goeckerman as a treatment for severe eczema is both effective and safe, it should be considered an excellent alternative or adjunct to the systemic therapies currently being used.

Concepts: Cancer, Ultraviolet, Electromagnetic spectrum, Sunlight, Eczema, Psoriasis, Psoralen, Coal tar


BACKGROUND: The majority of people with psoriasis have localised disease, where topical therapy forms the cornerstone of treatment. OBJECTIVE: To summarise evidence on relative efficacy, safety and tolerability of different topical treatments used in plaque psoriasis METHODS: Systematic review and meta-analyses of randomised trial data of UK-licensed topical therapies. The primary outcome was clear or nearly clear status stratified for (i) trunk and limbs and (ii) scalp. Network meta-analyses allowed ranking of treatment efficacy. RESULTS: 48 studies were available for trunk and limb psoriasis and 17 for scalp psoriasis (n=22,028); the majority included people with at least moderate psoriasis severity. Strategies containing potent corticosteroids (alone or in combination with a vitamin D analogue) or very potent corticosteroids, dominated the treatment hierarchy at both sites (trunk and limbs, scalp); coal tar and retinoids were no better than placebo. No significant differences in achievement of clear/nearly clear status were observed between twice and once daily application of the same intervention or between any of the following: combined vitamin D analogue and potent corticosteroid (applied separately or in a single product), very potent corticosteroids, or potent corticosteroids (applied twice daily). Investigator and patient assessment of response differed significantly for some interventions (response rate to very potent corticosteroids 78% and 39% respectively). No significant differences were noted for tolerability or steroid atrophy, but data were limited. CONCLUSIONS: Corticosteroids are highly effective and safe in psoriasis when used continuously for up to 8 weeks and intermittently for up to 52 weeks. Coal tar and retinoids are of limited benefit. There is a lack of long-term efficacy and safety data available on topical interventions used for psoriasis.

Concepts: Vitamin D, Ultraviolet, Randomized controlled trial, Sunlight, Efficacy, Psoriasis, Coal tar, Dandruff


Coal tar pitch (CTP) is a key factor in the development of occupational lung cancer. In order to investigate the function of the anti-oxidative signaling pathway regulated by NF-E2-related factor 2 (Nrf2) during cancer development, BEAS-2B cells were cultured with CTP extract for 30 passages. It was revealed that malignant transformation occurred in cells between the 20 and 30th passage. The expression levels of Nrf2 and NAD(P)H:quinone oxidoreductase 1 (NQO1) were promoted throughout the CTP exposure culture, and there was a positive linear correlation between the expression levels of Nrf2 and NQO1. Following knockdown of Nrf2 expression, the level of NQO1 decreased markedly and malignant transformation was more likely to occur. It was hypothesized that CTP may be toxic to BEAS-2B cells, which may lead to malignant transformation. Nrf2 was a quick response factor: Counteracting cytotoxicity by promoting the expression of anti-oxidative genes. Thus, Nrf2 was associated with the malignant transformation of BEAS-2B cells exposed to CTP and may be a potential therapeutic target.

Concepts: Gene, Gene expression, Cancer, Lung cancer, Organism, Culture, Tar, Coal tar


The aim of this work was to study an integration of micro-electrolysis with biological reactor (MEBR) for strengthening removal of phenolic compounds in coal gasification wastewater (CGW). The results indicated MEBR achieved high efficiencies in removal of COD and phenolic compounds as well as improvement of biodegradability of CGW under the micro-oxygen condition. The integrated MEBR process was more favorable to improvement of the structural stability of activated sludge and biodiversity of specific functional microbial communities. Especially, Shewanella and Pseudomonas were enriched to accelerate the extracellular electron transfer, finally facilitating the degradation of phenolic compounds. Moreover, MEBR process effectively relieved passivation of Fe-C filler surface and prolonged lifespan of Fe-C filler. Accordingly, the synergetic effect between iron-carbon micro-electrolysis (ICME) and biological action played a significant role in performance of the integrated process. Therefore, the integrated MEBR was a promising practical process for enhancing CGW treatment.

Concepts: Electron, Microbiology, Phenols, Coal, Chemical engineering, Phenolic compounds in wine, Gasification, Coal tar


Chemical analysis of soils contaminated with coal tar indicated that most organic compounds, and particularly PAHs, were contained in coarser particles (> 200 μm). Microscopic observations of this fraction, carried out on polished sections, reported the presence of organic particles in addition to mineral particles. Some organic particles had a very low porosity, and their microstructure did not evolve during biotreatment. Alternatively, other organic particles had a large porosity composed of an interconnected pore network that was open to coal tar surface and thus in contact with soil water. Interconnected porosity seemed to increase during biotreatment in relation to a decrease in the amount of organic compounds. The amount of open porosity in contact with soil water was expected to increase the desorption rate of PAHs. Consequently, the environmental hazard could depend on the amount of open porosity in addition to chemical properties of organic particles, such as their concentration in PAHs. Thus, microscopy can be complementary to chemical analysis and ecotoxicological assays to assess the best strategy for remediation but also to follow the advancement of a biotreatment.

Concepts: Chemistry, Soil, Analytical chemistry, Organic chemistry, Part, Porosity, Charcoal, Coal tar


Crude coal tar and its derivatives have been used in modern medicine for the treatment of psoriasis since at least 1925 as part of the Goeckerman regimen. To this day, coal tar remains a safe and highly effective option for the treatment of psoriasis vulgaris. However, the mechanism by which coal tar has its therapeutic effect is not known. This review summarizes current knowledge of the mechanism by which coal tar has its therapeutic effect in the treatment of psoriasis vulgaris.

Concepts: Pharmacology, Medicine, Petroleum, Effectiveness, Therapy, Psoriasis, Coal tar, Dandruff


Palmoplantar psoriasis is often disabling and refractory to conventional therapy. Systemic drugs are indicated in its severe form, but side effects are a concern with their use. Methotrexate is one such systemic drug which is effective and cheap. To reduce systemic toxicity, methotrexate has been tried topically but results have been inconsistent due to poor drug penetration into the skin by passive diffusion. Iontophoresis may enhance its absorption and efficacy.

Concepts: Pharmacology, Effectiveness, Drug, Skin, Psoriasis, Coal tar


Coal tars are a mixture of organic and inorganic compounds and were by-products from the manufactured gas and coke making industries. The tar compositions varied depending on many factors such as the temperature of production and the type of retort used. For this reason a comprehensive database of the compounds found in different tar types is of value to understand both how their compositions differ and what potential chemical hazards are present. This study focuses on the heterocyclic and hydroxylated compounds present in a database produced from 16 different tars from 5 different production processes.

Concepts: Oxygen, Carbon monoxide, Chemical compound, Charcoal, Coal, Tar, Coal tar, Coal gas


Coal tars are a mixture of organic and inorganic compounds and were by-products from the manufactured gas and coke making industries. Different manufacturing processes have resulted in the production of distinctly different tar compositions. This study presents a comprehensive database of compounds produced using two-dimensional gas chromatography combined with time-of-flight mass spectrometry (GCxGC/TOFMS), analysing 16 tar samples produced by 5 distinct production processes.

Concepts: Oxygen, Carbon monoxide, Coal, Manufacturing, Industry, Tar, Coal tar, Coal gas


Coal tars are a mixture of organic and inorganic compounds and were produced as a by-product from the manufactured gas and coke making industries. The composition of the tar produced varied depending on many factors; these include the temperature of production and the type of retort used. As different production processes produce different tars, a comprehensive database of the compounds present within coal tars from different production processes is a valuable resource. Such a database would help to understand how their chemical properties differ and what hazards the compounds present within these tars might pose. This study focuses on the aliphatic and aromatic compounds present in a database of 16 different tars from 5 different production processes.

Concepts: Benzene, Carbon monoxide, Chemical compound, Charcoal, Coal, Tar, Coal tar, Coal gas