Mutagenic activity of gastric fluid from chewers of tobacco with lime

Although tobacco chewing is strongly associated with a highrisk of oral and upper alimentary tract cancers, the natureof mutagenic exposure among users has not been clearly defined.In this study, tobacco-specific and mutagenic exposure of chewersof tobacco with lime was evaluated by analysis of gastric fluid(GF). The pH, nitrite and cotinine levels of GF samples fromchewers and non-chewers were determined and the samples weretested for mutagenicity in the Ames Sahnonella/microsome assayusing Salmonella typhimurium strains TA98, TA100 and TA102.Cotinine was not detected in GF from non-chewers while the levelsranged between 0.4–13.64 µg/ml in samples from chewers;however, the mean pH values (3.8 ± 0.4 versus 2.8 ±0.3) and nitrite levels (29.40 ± 1.51 versus 27.39 ±0.83 µM) were similar in both groups. While all GF samplesfrom non-chewers were non-mutagenic, samples from chewers weredirectly mutagenic or upon nitrosatlon to all the three testerstrains and to TA102 strain in the presence of S9. Experimentsusing scavengers of reactive oxygen species (ROS) showed thatmannitol and benzoate abolished the mutagenic response of TA102,indicating that ROS are principally responsible for oxidativedamage. The findings provide specific information regardingthe mutagenic exposure among tobacco chewers and suggest thattobacco chewing may be an important risk factor in the developmentof gastric cancer.     

Effects of dietary indole-3-carbinol on estradiol metabolism and spontaneous mammary tumors in mice

Indole-3-carbinol (I3C) is a potent inducer of cytochrome P450 enzymes in many species, including humans. We therefore studied alterations in the cytochrome P450-dependent metabolism of estradiol in different strains of mice consuming I3C in semisynthetic powdered diets at doses ranging from 250 to 5000 p.p.m. (34-700 mg/kg/day) for different periods of time. In short-term metabolic studies (3 weeks), wet liver weight increased in SW and C3H/OuJ mice in a dose-responsive manner. Dietary I3C increased the cytochrome P450 content measured in hepatic microsomes, as well as the extent of estradiol 2-hydroxylation, up to 5-fold. In a long-term feeding experiment (8 months), female C3H/OuJ mice consumed synthetic diets containing I3C at 0, 500 or 2000 p.p.m. Mammary tumor incidence and multiplicity were significantly lower at both doses of I3C, and tumor latency was prolonged in the high-dose group. We conclude that I3C is an inducer of hepatic P450-dependent estrogen metabolism in mice, and that it is chemopreventive in the C3H/OuJ mouse mammary tumor model. This protective effect may be mediated in part by the increased 2-hydroxylation and consequent inactivation of endogenous estrogens.     

Interferon-alpha and gamma mediated gene responses in a human breast carcinoma cell line

Interferons (IFNs) have been known to possess an antiproliferative effect on tumor cells besides their well characterized antiviral effect in cell cultures. The mechanism of action of the different IFNs is not fully understood, but in recent years a number of IFN-inducible genes, the presumed mediators of IFN action, have been identified. In the present study we examined the antiproliferative effect of IFN-alpha and IFN-gamma on human breast cancer cells (MCF-7) using (i) the MTT dye formation assay and (ii) anchorage-independent (AI) growth in soft agar. Both IFN-alpha and IFN-gamma were found to have an antiproliferative effect on the growth of MCF-7 cells. In addition, the kinetics of induction of a number of IFN-inducible genes was also examined. The expression of these genes was measured by mRNA analyses using specific [alpha-³²P]-labeled cDNAs as probes. The induction of these genes by IFN-alpha and IFN-gamma is a primary effect of IFN, asde novo protein synthesis is not required for their induction. Our results on the kinetics of induction of these genes by IFN-alpha and IFN-gamma suggests a complex mechanism of ligand-dependent gene activation in this cell line with some similar and dissimilar pathways.     

Evaluation of an alcohol-based surgical hand disinfectant containing a synergistic combination of farnesol and benzethonium chloride for immediate and persistent activity against resident hand flora of volunteers and with a novel in vitro pig skin model.

OBJECTIVE: To evaluate the immediate, persistent and sustained in vivo activity of an alcohol-based surgical hand disinfectant, consisting of a zinc gel and a preservative system containing a synergistic combination of farnesol and benzethonium chloride (ZBF disinfectant), and to develop a pig skin model for in vitro evaluation of the immediate and persistent efficacy of alcohol-based surgical hand disinfectants against resident hand flora. DESIGN: The in vivo immediate, persistent, and sustained activity of ZBF disinfectant was evaluated using human volunteers and the "glove-juice" method described in the US Food and Drug Administration's Tentative Final Monograph (FDA-TFM) for Healthcare Antiseptic Products. A novel in vitro pig skin model was developed to compare the immediate and persistent activity of alcohol-based surgical hand disinfectants against resident flora using Staphylococcus epidermidis as the test organism. Four alcohol-based surgical hand disinfectants were evaluated using this model. RESULTS: The results for the ZBF disinfectant exceed the FDA-TFM criteria for immediate, persistent, and sustained activity required for surgical hand disinfectants. The reduction factors for the 4 hand disinfectants obtained using the pig skin model show good agreement with the log(10) reductions in concentrations of hand flora obtained using human volunteers to test for immediate and persistent activity. CONCLUSION: The ZBF disinfectant we evaluated met the FDA-TFM criteria for surgical hand disinfectants. The immediate and persistent efficacy of the surgical hand disinfectants evaluated with the novel pig skin model described in this study shows good agreement with the results obtained in vivo.     

Lipodystrophy of Abdominal Pannus: A Severe Complication of Phosphatidyl Choline Injections

“Injection lipolysis” or “mesotherapy” is done for introducing various substances into deeper layers of the skin with the aim to dissolve subcutaneous fat. However, the safety profile of these chemicals is poorly regulated. Therefore, they may cause side effects or long-term sequelae that can be disastrous for the patient. We present such a case that required surgical management to salvage it and to give an aesthetically acceptable result.     

Acute recurrence of orbital cavernous hemangioma in a young man: a case report

A 29-year-old man presented with a history of prominent left eye of 6 months' duration. He also reported fluctuating blurred vision since 15 days ago. On examination, proptosis of 3 mm was noted in the left eye. Computed tomography (CT scan) of the orbits showed a well-circumscribed, hyperdense, intraconal mass lesion in left orbit, located in the inferotemporal quadrant. Orbitotomy was performed, and the tumor was delivered with an intact capsule. The clinical diagnosis of cavernous hemangioma was confirmed on histopathologic examination. The presence of intact capsule was confirmed grossly and with histopathology. The patient returned 6 weeks after surgery with recurrent proptosis. Repeated CT scan showed a recurrent intraconal mass of similar characteristics as in the primary presentation. A repeated orbitotomy was done, and the tumor was removed intact. Histopathology of the recurrent tumor confirmed the diagnosis of cavernous hemangioma. We report a rare case of orbital cavernous hemangioma with short-term recurrence (6 weeks).