Updated view of tars for psoriasis: what have we learned over the last decade?

Tars are one of the most effective, unknown, and oldest therapies for psoriasis. They include coal tar (CT) and biomass-derived products. These treatments, particularly the CT, have proven to be cost-effective with long remission times compared to other systemic or topical treatments. However, they have hardly evolved in recent years, as they are not well-embraced by clinicians or patients because of concerns regarding cosmesis and safety. This review summarizes current knowledge about the chemical characterization, mechanism of action, toxicity, and clinical studies supporting the use of tars for psoriasis over the last decade. Trends within these above aspects are reviewed, and avenues of research are identified. CT is rich in polycyclic aromatic hydrocarbons, whereas biomass-derived tars are rich in phenols. While the activation of the aryl hydrocarbon receptor is involved in the antipsoriatic effect of CT, the mechanism of action of biomass-derived products remains to be elucidated. No conclusive evidence exists about the risk of cancer in psoriasis patients under CT treatment. Large, randomized, double-blind, controlled clinical trials are necessary to promote the inclusion of tars as part of modern therapies for psoriasis.

Comparison Between Two Strategies of Topical Treatment in Tar Burn: A Case Report.

The management of tar burns presents a wide range of possible approaches, and several strategies can be used to reduce the damage regarding the removal of tar adhered to the patient's skin. Tar residues should preferably be emulsified with solvent solutions. Due to the low incidence of tar burns, it has not yet been possible to select the appropriate agent for the removal of the adhered tar. In this article, we reported a case of a 47-year-old man with a tar burn in his forehead region and his both upper limbs treated with two different approaches and the outcomes. In the right upper limb, the removal of tar with oil-based on essential fatty acids was attempted at the time of hospital admission, whereas in the left upper limb, he was treated with 1% silver sulfadiazine cream, sterile gauze, and bandage. On the right upper limb, the treatment was eventually performed with debridement and split-thickness skin grafting. On the left upper limb, there was complete re-epithelialization of the burns. The more conservative approach of keeping a dressing with 1% silver sulfadiazine on the tar itself, followed by removing the material in the dressing changes was considered better than the immediate removal of tar with an oily solution, especially about pain. Our impression was that the application of 1% silver sulfadiazine cream at the time of the admission, as well as in the following days, may be beneficial for the removal of the tar in close contact with the skin. Possibly, this approach leads to less trauma to the skin and, eventually, simplifies the treatment of burns by hot tar.

Systematic Review and Meta-Analysis of Inhaled Toxicants from Waterpipe and Cigarette Smoking.

OBJECTIVE: Waterpipe tobacco smoking (WTS) is an emerging trend worldwide. To inform public health policy and educational programming, we systematically reviewed the biomedical literature to compute the inhaled smoke volume, nicotine, tar, and carbon monoxide (CO) associated with a single WTS session and a single cigarette. METHODS: We searched seven biomedical bibliographic databases for controlled laboratory or natural environment studies designed to mimic human tobacco consumption. Included studies quantified the mainstream smoke of a single cigarette and/or single WTS session for smoke volume, nicotine, tar, and/or CO. We conducted meta-analyses to calculate summary estimates for the inhalation of each unique substance for each mode of tobacco consumption. We assessed between-study heterogeneity using chi-squared and I-squared statistics. RESULTS: Sufficient data from 17 studies were available to derive pooled estimates for inhalation of each exposure via each smoking method. Two researchers working independently abstracted measurement of smoke volume in liters, and nicotine, tar, and CO in milligrams. All numbers included in meta-analyses matched precisely between the two researchers (100% agreement, Cohen's k=1.00). Whereas one WTS session was associated with 74.1 liters of smoke inhalation (95% confidence interval [CI] 38.2, 110.0), one cigarette was associated with 0.6 liters of smoke (95% CI 0.5, 0.7). One WTS session was also associated with higher levels of nicotine, tar, and CO. CONCLUSIONS: One WTS session consistently exposed users to larger smoke volumes and higher levels of tobacco toxicants compared with one cigarette. These computed estimates may be valuable to emphasize in prevention programming.

A baseline assessment of beach debris and tar contamination in Bonaire, Southeastern Caribbean.

Data on beach debris and tar contamination is provided for 21 natural beach sites in Bonaire, Southeastern Caribbean. Transects amounting to a combined length of 991 m were sampled March-May 2011 and a total of 8960 debris items were collected. Highest debris and tar contamination were found on the beaches of the windward east-coast of the island where geometric mean debris concentrations (± approx. 70% confidence limits) were 115±58 items m(-1) and 3408±1704 g m(-1) of beach front. These levels are high compared to data collected almost 20 years earlier on the nearby island of Curaçao. Tar contamination levels averaged 223 g m(-1) on windward beaches. Contamination levels for leeward west-coast beaches were generally two orders of magnitude less than windward beaches.

A bio-inspired sensor based on surfactant film and Pd nanoparticles.

A bio-inspired complex, [(bpbpmp)Fe(III)(m-OAc)(2)Cu(II)](ClO(4)), was combined with a zwitterionic surfactant (ImS3-14) stabilizing pre-formed palladium nanoparticles and coated on a glassy carbon electrode (GCE). This bio-inspired surfactant film was capable of catalyzing redox reactions of dihydroxybenzenes, thus allowing the simultaneous electrochemical quantification of CC and HQ in cigarette residue samples by square-wave voltammetry (SWV). The best experimental conditions were obtained using phosphate buffer solution (0.1 mol L(-1), pH 7.0), with 1.3 nmol of the bio-inspired complex, 0.15 µmol of the surfactant and 1.08 nmol of Pd. The best voltammetric parameters were: frequency 100 Hz, pulse amplitude 40 mV and step potential 8 mV. The limits of detection calculated from simultaneous curves were found to be 2.2 × 10(-7) and 2.1 × 10(-7) mol L(-1) for HQ and CC respectively.

Illicit tobacco trade between the United States and Mexico.

OBJECTIVE: To provide a brief history of the illicit tobacco trade between Mexico and the United States. MATERIALS AND METHODS: Research included a previously published study: "Cigarette taxes and smuggling: A statistical analysis and historical review", published by the Mackinac Center for Public Policy; US Customs and Border Protection data; various US court documents; General Accountability Office reporting; media reports; other historical material, and a personal interview. RESULTS: The research revealed that there is no credible evidence of organized criminal activity related to the illicit trade in tobacco products from Mexico into the United States. However, there is clear and convincing evidence of organized criminal activity in smuggling tobacco products from the United States into Mexico for at least 167 years. CONCLUSION: Historical records from 1845 into the 21st century clearly demonstrate that the United States was usually the source country for tobacco products moving illegally between the two countries.

Illicit tobacco trade between the United States and Mexico / El comercio ilícito de tabaco entre los Estados Unidos y México

OBJECTIVE: To provide a brief history of the illicit tobacco trade between Mexico and the United States. MATERIALS AND METHODS: Research included a previously published study: "Cigarette taxes and smuggling: A statistical analysis and historical review", published by the Mackinac Center for Public Policy; US Customs and Border Protection data; various US court documents; General Accountability Office reporting; media reports; other historical material, and a personal interview. RESULTS: The research revealed that there is no credible evidence of organized criminal activity related to the illicit trade in tobacco products from Mexico into the United States. However, there is clear and convincing evidence of organized criminal activity in smuggling tobacco products from the United States into Mexico for at least 167 years. CONCLUSION: Historical records from 1845 into the 21st century clearly demonstrate that the United States was usually the source country for tobacco products moving illegally between the two countries.

OBJETIVO: Describir brevemente la historia del comercio ilícito de tabaco entre Estados Unidos y México. MATERIAL Y MÉTODOS: La investigación incluye publicaciones previas, como "Impuestos sobre los cigarrillos y el contrabando: Un análisis histórico y estadístico"; datos de la Agencia de Aduanas y Protección Fronteriza; varios documentos de la Corte; los informes de la Oficina General de Rendición de Cuentas de EU; notas de prensa; materiales históricos, y una entrevista personal. RESULTADOS: La investigación reveló que no hay pruebas creíbles de actividad delictiva organizada relacionada con el comercio ilícito de productos de tabaco de México a EU. Sin embargo, hay pruebas claras y convincentes de que esta actividad se ha realizado de EU a México por lo menos durante 167 años. CONCLUSIÓN: Los registros históricos desde el año 1845 claramente demuestran que EU solía ser el país de origen del tabaco ilegal entre los dos países.

Actions of redox-active compound resveratrol under hydrogen peroxide insult in C6 astroglial cells.

The mechanisms by which resveratrol (3,5,4'-trihydroxy-stilbene) imparts neural effects is not well understood. We previously demonstrated that, depending upon the concentration of resveratrol and the cell type, this compound exerts anti-or pro-oxidant effects. In the present study, we investigated the effects of resveratrol on H(2)O(2)-mediated genotoxicity in C6 astroglial cells (I - 1mM H(2)O(2)/30 min or II - 0.1mM H(2)O(2)/6h), evaluated by micronucleus assay, lipid peroxidation (TBARS) and membrane integrity. H(2)O(2) increased micronuclei to 1.5 (I) and 1.7-fold (II), compared to control cells. This DNA damage was prevented (I) or partially prevented (II) by resveratrol. Oxidative insult also increased TBARS, 52% in I and 38% in II, P<0.05. These effects were prevented by resveratrol in I and increased in II (70% of increase). Present data contribute to the understanding of resveratrol effects under oxidative stress damage.

Average structural analysis of tar obtained from pyrolysis of wood.

Conventional analytical methods such as (1)H NMR, vapor pressure osmometry (VPO) and elemental analysis were used to characterize the tar obtained from pyrolysis of pine. The major fraction of tar obtained during pyrolysis of pine at different temperatures was the insoluble fraction in n-heptane which corresponds to asphaltenes; this fraction was characterized and analyzed using average structural parameters. The structural unit of the tar is composed of one aromatic ring substituted by aliphatic chains, olefinic groups and the presence of oxygenated groups. Two of such average structures determined with this methodology corresponds to 4-formyl-2,6-dimethoxy-3-[(1E)-prop-1-en-1-yl]-5-propylbenzoic acid and 2,3,5-trimethoxy-6-[(1E)-prop-1-en-1-yl]-4-propylbenzaldehyde.

Novel highly reactive and regenerable carbon/iron composites prepared from tar and hematite for the reduction of Cr(VI) contaminant.

Highly reactive carbon/Fe composites were prepared from tar used as a carbon source, and hematite (alpha-Fe(2)O(3)), a widespread naturally available iron oxide. Tar was impregnated on hematite and thermally treated under N(2) atmosphere. Mössbauer, powder X-ray diffraction and magnetization data suggested that treatment at 400 and 600 degrees C produced only magnetite (Fe(3)O(4)) whereas at 800 degrees C mainly metallic iron (Fe(0)) was produced. Raman, TG and XRD analyses of the different composites revealed the presence of amorphous and graphitic carbon highly dispersed on the iron oxide surface. The composites obtained at 800 degrees C were very efficient in reducing aqueous Cr(VI), as CrO(4)(2-), even compared to finely ground commercial Fe(0). XPS and Mössbauer data showed that after five consecutive reuses, the composites deactivated, due to the surface oxidation of Fe(0). A simple treatment at 800 degrees C completely regenerated the composite by reducing Fe(3+) species allowing several reuses.

Low- and high-yield cigarette smoke inhalation potentiates bone loss during ligature-induced periodontitis.

BACKGROUND: It is well recognized that cigarette consumption is a strong risk factor for periodontitis. Tobacco companies have developed a cigarette with low levels of toxic compounds; however, its effect on periodontium has not been investigated. The aim of this study was to verify the impact of smoke produced by low- and high-yield cigarettes on bone loss resulting from ligature-induced periodontitis. METHODS: A total of 36 male Wistar rats were used in the study. A ligature was placed around one of the mandibular first molars (ligated teeth) of each animal, and they were assigned randomly to one of three groups: group 1: control (N = 10), group 2: 30 days' inhalation of smoke produced by high-yield cigarettes (N = 13), and group 3: 30 days' inhalation of smoke produced by low-yield cigarettes (N = 13). The animals were sacrificed 30 days after ligature placement, and the specimens were processed for decalcified sections. RESULTS: Intergroup analysis of unligated teeth (without periodontal disease) did not show a significant difference regarding periodontal ligament area (2.40 +/- 0.5 mm(2), 2.72 +/- 0.7 mm(2), and 2.61 +/- 0.4 mm(2) for groups 1, 2, and 3, respectively; P >0.05). Conversely, significant differences were noted in ligated teeth (with periodontitis); bone loss was directly proportional to the level of toxic compounds in the cigarettes (5.74 +/- 0.5 mm(2), 7.40 +/- 0.50 mm(2), and 6.51 +/- 0.50 mm(2) for groups 1, 2, and 3, respectively; P <0.05). CONCLUSION: Low- and high-yield cigarettes potentiated bone loss during experimental periodontitis in a directly proportional fashion.

Cotinine concentration in smokers from different countries: relationship with amount smoked and cigarette type.

This four-country study examined salivary cotinine as a marker for nicotine intake and addiction among smokers in relation to numbers and types of cigarettes smoked. Smoking characteristics of cigarette smokers in Brazil, China, Mexico, and Poland were identified using a standard questionnaire. Cotinine concentration was measured using a saliva sample from each participant; its relationship with numbers and types of cigarettes smoked was quantified by applying regression techniques. The main outcome measure was salivary cotinine level measured by gas chromatography. In all four countries, cotinine concentration increased linearly with cigarettes smoked up to 20 per day [11.3 ng/mL (95% confidence interval, 10.5-12.2)] and then stabilized as the number of cigarettes exceeded 20 [6.8 ng/mL per cigarette (95% confidence interval, 6.3-7.4) for up to 40 cigarettes]. On average, smokers of regular cigarettes consumed more cigarettes and had higher cotinine levels than light cigarette smokers. Cotinine concentration per cigarette smoked did not differ between regular and light cigarette smokers. Results suggest a saturation point for daily nicotine intake and minimal or no reduction in nicotine intake by smoking light cigarettes.

High molecular weight polycyclic aromatic hydrocarbons in hydrothermal petroleums from the Gulf of California and Northeast Pacific Ocean.

Hydrothermal petroleums and heavy tars have been analyzed for polycyclic aromatic hydrocarbons (PAH) with molecular weights greater than that of coronene (300 da). Samples from the hydrothermal systems in the Guaymas Basin (Gulf of California) and in the Escanaba Trough and Middle Valley (Northeastern Pacific) were analyzed by gas chromatography-mass spectrometry and high pressure liquid chromatography with diode-array absorbance detection. Mass spectra and fluorescence spectra were used to characterize the compounds. Several large PAHs with six and more rings were identified among the heavy PAH. Production routes via one-ring build-up and Scholl-condensation are proposed to explain the observed structures. The variations in PAH concentrations and distributions between samples from different locales are a consequence of the hydrothermal conditions of generation, migration, and post-depositional alteration.

Composition of tobaccos from countries with high and low incidences of lung cancer. I. Selenium, polonium-210, Alternaria, tar, and nicotine.

Tobaccos from countries with high and low incidences of lung cancer were analyzed. Tobacco concentrations of polonium-210 were similar in cigarettes from high- and low-incidence countries, as were levels of cigarette smoke tar and nicotine. Tobaccos from low-incidence countries had significantly lower Alternaria spore counts. Mean selenium concentrations of tobaccos from the high-incidence countries (0.16 +/- 0.05 micrograms/g) were significantly lower than those of tobaccos from the low-incidence countries (0.49 +/- 0.22 micrograms/g).

Terapeutica de afeccoes do couro cabeludo pela associacao de um topico com betametasona - 17 valerato e um xampu de derivados do alcatrao. / Treatment of scalp diseases with a combination of topic betametasone- 17 valerate and a shampoo of tar derivatives

Foram tratados 26 casos de afeccoes do couro cabeludo, sendo 11 casos de dermatite seborreica, 11 casos de pitiriase capitis e 4 casos de psoriase, com a associacao de um produto topico de betametasona 17 valerato e um xampu de alcatroes de diversas origens. Os resultados foram considerados bons em 10 dos 11 casos de Dermatite seborreica, em todos os casos de pitiriase capitis e 3 casos moderados dos 4 casos de psoriase