Oral complications of head and neck radiotherapy: prevalence and management.

AIM: The aim of the study was to evaluate the short-term and long-term toxicity caused by radiation treatment in the head and neck with the technique of intensity-modulated radiotherapy (IMRT). METHODS: We selected 20 patients, 18 men and 2 women aged between 21 and 71 years, undergoing radiation therapy (IMRT) in head and neck. Patients were visited during radiotherapy and followed for six months after the end of the therapy. We assessed the presence of: mucositis, xerostomia, dysgeusia, dysphagia, pain, trismus and, in the case of late-onset complications, radiation cavities. RESULTS: Acute toxicity: in 20 patients, 18 reported mucositis, 19 xerostomia, 17, dysgeusia, 15 dysphagia, 18 had pain and 3 patients had trismus. Tardive toxicity: in 14 patients, 5 reported mucositis, 11 xerostomia, 6 dysgeusia, 2 dysphagia, 3 had pain, 4 trismus and in 4 patients were found radiation cavities. CONCLUSION: Acute complications with higher prevalence were xerostomia (19 of 20 patients), dysgeusia of 2nd grade (11 patients of 20), mucositis of 1st grade and pain of 1st grade (10 patients of 20). Among the late complications it was noted a maintenance of the high prevalence of xerostomia (11 patients of 14) and an increase in prevalence of trismus (4 patients of 14) against a reduction of all other complications. The presence of radiation cavities in 4 patients of 14 was also recorded.

HPV and oral lesions: preventive possibilities, vaccines and early diagnosis of malignant lesions.

The importance of HPV in world healthy is high, in fact high-risk HPV types contribute significantly to viral associated neoplasms. In this article we will analyze vary expression of HPV in oral cavity both benign and malignant, their prevalence and the importance in early diagnosis and prevention. The classical oral lesions associated with human papillomavirus are squamous cell papilloma, condyloma acuminatum, verruca vulgaris and focal epithelial hyperplasia. Overall, HPV types 2, 4, 6, 11, 13 and 32 have been associated with benign oral lesions while HPV types 16 and 18 have been associated with malignant lesions, especially in cancers of the tonsils and elsewhere in the oropharynx. Transmission of the virus can occur with direct contact, genital contact, anal and oral sex; latest studies suggest a salivary transmission and from mother to child during delivery. The number of lifetime sexual partners is an important risk factor for the development of HPV-positive head-neck cancer. Oral/oropharyngeal cancer etiologically associated with HPV having an increased survival and a better prognostic (85%-90% to five years). There is no cure for the virus. There are two commercially available prophylactic vaccines against HPV today: the bivalent (16 and 18) Cervarix® and the tetravalent (6, 11, 16 and 18) Gardasil® and new vaccine Gardasil 9 (6, 11, 16, 18, 31, 33, 45, 52, 58) was approved in the United States. To be effective, such vaccination should start before "sexual puberty". The vaccine could be an important preventive strategy, in fact the scientific community is in agreement on hypothesis that blocking the contagion it may also limit the distance complications as the oropharyngeal cancer.

Mechanism of intestinal formation of deoxycholic acid from cholic acid in humans: evidence for a 3-oxo-delta 4-steroid intermediate.

12 alpha-Hydroxy-3-oxo-4-cholenoic acid coupled to an adenosine nucleotide has been shown to be a metabolite of cholic acid in the intestinal anaerobic bacteria, Eubacterium species VPI 12708 (1987. J. Biol. Chem. 262: 4701-4707) and it has been suggested that this may be an intermediate in the conversion of cholic acid into deoxycholic acid. The possibility that the intestinal conversion of cholic acid into deoxycholic acid involves a 3-oxo-delta 4-steroid as an intermediate has been studied in the present work by use of [3 beta-3H]- and [5-3H]-labeled cholic acid. Whole cells as well as cell extracts of Eubacterium sp. VPI 12708 catalyzed conversion of [3 beta-3H] + [24-14C]cholic acid into deoxycholic acid with loss of about 50% of 3H label. When unlabeled chenodeoxycholic acid (20 microM) was added along with [3 beta-3] + [24-14C]cholic acid, then approximately 85% of the [3 beta-3H]-labeled was lost from deoxycholic acid. After administration of the same mixture to two healthy volunteers, deoxycholic acid could be isolated that had lost 81 and 84%, respectively, of the 3H label. Conversion of a mixture of [5-3H]- and [24-14C]labeled cholic acid by the above intestinal bacteria or cell extracts led to loss of 79-94 of the [5-3H] label.(ABSTRACT TRUNCATED AT 250 WORDS)

Genetic aspects of aflatoxin B1 resistance in Drosophila melanogaster.

Fifteen wild-type laboratory strains of Drosophila melanogaster were tested for egg-adult viability when exposed to larval development in media containing 0.5 and 1.0 ppm aflatoxin B (AFB1). Significant variation among the strains was demonstrated, especially at the 0.5 ppm AFB1 concentration. Two resistant and two sensitive strains were made isogenic and mated in a 4 X 4 diallel system. Results indicate that differences in AFB1 sensitivity are due to genes with additive effects on viability and that nonsystematic effects due to the interaction of cytoplasms and genes of both paternal and maternal origin are present. A chromosome/cytoplasm substitution analysis was performed using one of the sensitive and one of the resistant strains. Results indicate that genes on chromosomes X and 2 contribute to egg-adult viability differences observed for larval growth on media containing 0.5 and 1.0 ppm AFB1. Also, a significant interaction between chromosome 2 and cytoplasm, both from the resistant strain, was observed, resulting in a twofold increase in viability at 0.5 ppm AFB1 when compared to controls. Possible relationships of these findings with those from vertebrate systems are discussed.