Microwave sanitization of color additives used in cosmetics: feasibility study.
(9/238)
Microwave exposure has been explored as a method of microbiologically sanitizing color additives used in cosmetic products. Selected microbiologically unacceptable cosmetic color additives, D&C red no. 7 Ca lake (certified synthetic organic color), carmine (natural organic color not subject to certification), and chromium hydroxide green (inorganic color not subject to certification), were submitted to microwave exposure. Gram-negative bacteria were eliminated, as verified by enrichment procedures, and levels of gram-positive bacteria were reduced. Generally, analytical and dermal safety studies indicated no significant alterations in physical, chemical, and toxicological properties of the colors. Sanitization was also successfully performed on other colors (D&C red no. 9 Ba lake, D&C red no. 12 Ba lake, D&C green no. 5, and FD&C red no. 4); initial physical and chemical tests were satisfactory. Results indicated that this method of sanitization is feasible and warrants further investigation. (+info)
Bioavailability of octamethylcyclotetrasiloxane (D(4)) after exposure to silicones by inhalation and implantation.
(10/238)
We developed a physiologically based pharmacokinetic (PBPK) model to predict the target organ doses of octamethylcyclotetrasiloxane (D(4)) after intravenous (IV), inhalation, or implantation exposures. The model used (14)C-D(4) IV disposition data in rats to estimate tissue distribution coefficients, metabolism, and excretion parameters. We validated the model by comparing the predicted blood and tissues concentrations of D(4) after inhalation to experimental results in both rats and humans. We then used the model to simulate D(4) kinetics after single and/or repeated D(4) exposures in rats and humans. The model predicted bioaccumulation of D(4) in fatty tissues (e.g., breast), especially in women. Because of its high lipid solubility (Log P(oct/water) = 5.1), D(4) persisted in fat with a half life of 11.1 days after inhalation and 18.2 days after breast implant exposure. Metabolism and excretion remained constant with repeated exposures, larger doses, and/or different routes of exposure. The accumulation of D(4) in fatty tissues should play an important role in the risk assessment of D(4) especially in women exposed daily to multiple personal care products and silicone breast implants. (+info)
A facile spectrophotometric method for the determination of selenium.
(11/238)
A rapid and sensitive spectrophotometric method is described for the determination of trace amounts of selenium using Variamine Blue (VB) as a chromogenic reagent. The proposed method is based on the reaction of selenium with potassium iodide in an acidic medium to liberate iodine, which oxidizes Variamine Blue to form a violet-colored species having an absorption maximum at 546 nm. Beer's law is obeyed in the range 2-20 g of selenium in a final volume of 10 ml. The molar absorptivity and Sandell's sensitivity were found to be 2.6 x 10(4) l mol-1 cm-1 and 0.003 microgram cm-2, respectively. The optimum reaction conditions and other analytical parameters were evaluated. The effect of interfering ions on the determination is described. The proposed method has been successfully applied to the determination of selenium in real samples of water, soil, plant materials, human hair, and synthetic samples of cosmetics and pharmaceutical preparations. (+info)
Possible relation of Tunisian pemphigus with traditional cosmetics: a multicenter case-control study.
(12/238)
Pemphigus is a severe, autoimmune, blistering disorder with a high incidence among young women in rural Tunisia. The authors investigated explanatory environmental factors. A multicenter case-control study was conducted prospectively from 1992 to 1996 in Tunisia. Sixty-eight incident female cases of pemphigus and 166 controls matched on age, hospital, and geographic area were included. Data collected concerned socioeconomic status, medical history, drug intakes, lifestyle, and environment. Several factors were significantly associated with pemphigus in multivariate logistic regression analyses: traditional cosmetics (odds ratio (OR) = 4.0, 95% confidence interval (CI): 1.1, 14.8); Turkish baths (OR = 3.2, 95% CI: 1.4, 7.3); cutting up raw poultry (OR = 5.1, 95% CI: 1.3, 19.4); contact with ruminants (OR = 2.7, 95% CI: 1.3, 5.8); and wasp, bee, and spider stings (OR = 3.1, 95% CI: 1.5, 6.4). A dose-dependent relation was observed for traditional cosmetics. All risks except insect bites were higher when analysis was restricted to younger women, the demographic group with higher incidence. The strength of the associations, the dose-dependent relation for traditional cosmetics, and the increase of risk estimates for younger women support a causal relation. Traditional cosmetics widely used by Tunisian women could play a major role in excess of cases of pemphigus. (+info)
Identification of the cytochromes P450 that catalyze coumarin 3,4-epoxidation and 3-hydroxylation.
(13/238)
Coumarin, a widely used fragrance ingredient, is a rat liver and mouse lung toxicant. Species differences in toxicity are metabolism-dependent, with injury resulting from the cytochrome P450-mediated formation of coumarin 3,4-epoxide (CE). In this study, the enzymes responsible for coumarin activation in liver and lung were determined. Recombinant human and rat CYP1A forms and recombinant human CYP2E1 readily catalyzed CE production. Coinhibition with CYP1A1/2 and CYP2E1 antibodies blocked CE formation by 38, 84, and 67 to 92% (n = 3 individual samples) in mouse, rat, and human hepatic microsomes, respectively. Although CYP1A and 2E forms seem to be the most active catalysts of CE formation in liver, studies conducted with the mechanism-based inhibitor 5-phenyl-pentyne demonstrated that CYP2F2 is responsible for up to 67% of CE formation in whole mouse lung microsomes. In contrast to the CE pathway, coumarin 3-hydroxylation is a minor product of coumarin in liver microsomes from mice, rats, and humans and is catalyzed predominately by CYP3A and CYP1A forms, confirming that CE and 3-hydroxycoumarin are formed via distinct metabolic pathways. (+info)
Pharmaceuticals from natural products: current trends.
(14/238)
The use of products extracted from plants for medicinal purposes can be traced to the beginnings of civilization and up until the end of the nineteenth century natural products were the principal source of medicines. Since then their relative importance has oscillated according to the strategies of large pharmaceutical companies. Now that these strategies are changing, there are new opportunities for countries like Brazil, in which a large proportion of the world's biodiversity is located. There are, however, new circumstances that must be taken into consideration: material must be collected by groups which are formally authorized to do so and under the conditions of the Convention of Biological Diversity, the discovery process is being successively outsourced to smaller specialized firms and there is a growing integration with producers of cosmetics and phytomedicines. (+info)
Randomized trial of breast irradiation schedules after lumpectomy for women with lymph node-negative breast cancer.
(15/238)
BACKGROUND: Breast irradiation after lumpectomy is an integral component of breast-conserving therapy that reduces the local recurrence of breast cancer. Because an optimal fractionation schedule (radiation dose given in a specified number of fractions or treatment sessions over a defined time) for breast irradiation has not been uniformly accepted, we examined whether a 22-day fractionation schedule was as effective as the more traditional 35-day schedule in reducing recurrence. METHODS: Women with invasive breast cancer who were treated by lumpectomy and had pathologically clear resection margins and negative axillary lymph nodes were randomly assigned to receive whole breast irradiation of 42.5 Gy in 16 fractions over 22 days (short arm) or whole breast irradiation of 50 Gy in 25 fractions over 35 days (long arm). The primary outcome was local recurrence of invasive breast cancer in the treated breast. Secondary outcomes included cosmetic outcome, assessed with the European Organisation for Research and Treatment of Cancer (EORTC) Cosmetic Rating System. All statistical tests were two-sided. RESULTS: From April 1993 through September 1996, 1234 women were randomly assigned to treatment, 622 to the short arm and 612 to the long arm. Median follow-up was 69 months. Five-year local recurrence-free survival was 97.2% in the short arm and 96.8% in the long arm (absolute difference = 0.4%, 95% confidence interval [CI] = -1.5% to 2.4%). No difference in disease-free or overall survival rates was detected between study arms. The percentage of patients with an excellent or good global cosmetic outcome at 3 years was 76.8% in the short arm and 77.0% in the long arm; the corresponding data at 5 years were 76.8% and 77.4%, respectively (absolute difference = -0.6%, 95% CI = -6.5% to 5.5%). CONCLUSION: The more convenient 22-day fractionation schedule appears to be an acceptable alternative to the 35-day schedule. (+info)
Occupational airborne and hand dermatitis to hop (Humulus lupulus) with non-occupational relapses.
(16/238)
We report a case of a 57-years-old female farmer with occupational airborne dermatitis and hand dermatitis to hop (Humulus lupulus). The disease appeared at the age of 46, after 30 years of working with hop without any health problems. The patient had skin erythema of the face, neck and decollete , oedema of the eyelids, conjunctivitis, as well as acute dermatitis of the hands. The symptoms were provoked both by fresh and dried hop, appeared after half-an-hour of working and persisted over 1-2 days. There were no other skin or allergic problems. Skin tests were carried out with hop leaves (saline extract: prick positive, patch negative; glycerol extract: prick positive, patch negative) and hop cones (saline extract: prick positive, patch negative; glycerol extract: prick negative, patch positive after 48 and 72 hours). Despite discontinuing work, the patient experienced several relapses of her dermatitis. We identified new sources of hop allergens: a beauty cream and a herbal sedative, both containing hop extract. During the next hop cultivation period it also turned out that sleeping in one bed with her husband was provoking relapses of the patient's dermatitis. The husband admitted that sometimes he felt too tired to wash thoroughly after working on the plantation. Our case shows that connubial contacts with husband working in the same workplace may cause relapses of occupational dermatitis. To our knowledge, this is the first report on the concurrent occupational and connubial dermatitis to hop. (+info)