Etiology of oral submucous fibrosis with special reference to the role of areca nut chewing

Oral submucous fibrosis (OSF) is a high risk precancerous condition, predominantly affecting Indians. Consumption of chilli was hypothesized as an etiologic factor on the basis of ecological observations and a solitary animal experimental study. Subsequent epidemiologic studies that included case-series reports, large cross-sectional surveys, case-control studies, cohort and intervention studies have identified areca nut as the major etiologic agent. Tissue-culture studies involving human fibroblasts, areca nut extracts and areca nut alkaloids supported this etiologic hypothesis by showing fibroblastic proliferation and increased collagen formation. Currently, the role of genetic susceptibility and that of autoimmunity are receiving attention. The influence of nutritional factors, if any, remains unclear.     

Hyposensitization to poison ivy after working in a cashew nut shell oil processing factory

19 adults were patch tested to urushiol, the allergen in poison ivy/oak, to determine their sensitivity to this allergen after working in a cashew nut shell oil (CNSO) processing plant. The cashew nut tree and poison ivy/oak are in the same botanical family. Anacardiaceae, and they share similar chemicals which cause allergic contact dermatitis. 13 of the 19 workers had a preemployment history of poison ivy sensitivity, with 10 developing CNSO dermatitis. After working in this factory for several months, 9 of the 13 noticed a decreased sensitivity or no sensitivity to poison ivy/oak. When tested to urushiol extract, only 3 reacted positively, 2 minimally. These results imply that hyposensitization to poison ivy/oak occurred in these employees after development of hardening to cashew nut shell oil.     

The effectiveness of school educating program for betel quid chewing: A pilot study in Papua New Guinea

Background

To investigate the effectiveness of educating program among primary and secondary school students in Papua New Guinea, where has the highest incidence of oral cancer all over the world.

The Effects of Preventive Intervention for Betel Nut Chewing in School

Abstract

Purpose: This study was to explore the effect of preventive health education intervention in the knowledge, attitude, practice of betel nut chewing, and self-efficacy of anti-betel nut chewing for adolescent students.

Methods: One hundred eighty-six indigenous samples were recruited, and divided into experimental and control groups. The experimental group underwent fourteen-week classes regarding the prevention of betel nut chewing. Both groups took post-tests immediately after intervention in order to evaluate the instant effect of the teaching program. The follow-up (post-post-test) evaluated the instant improvement at the 28th week (14 weeks after the end of the class).

Results: There was no difference in knowledge of the hazards of betel nut chewing among pre-tests, post-tests, and post-post-test in the experimental group. The attitude, practice of betel nut chewing and self-efficacy of anti-betel nut chewing aspects was significantly different among pre-tests, post-tests, and post-post-test after intervention. There was a significantly immediate and instant improvement after health education intervention.

Conclusion: Health education enables students to better resist the use of betel nuts. This study confirmed the importance of health education programs in dealing with the health risks of betel nut chewing for the risk group Students.     

MALDI-TOF mass spectrometry analysis of small molecular weight compounds (under 10 KDa) as biomarkers of rat hearts undergoing arecoline challenge

Context: Statistical and clinical reports indicate that betel nut chewing is strongly associated with progression of oral cancer because some ingredients in betel nuts are potential cancer promoters, especially arecoline. Early diagnosis for cancer biomarkers is the best strategy for prevention of cancer progression. Several methods are suggested for investigating cancer biomarkers. Among these methods, gel-based proteomics approach is the most powerful and recommended tool for investigating biomarkers due to its high-throughput. However, this proteomics approach is not suitable for screening biomarkers with molecular weight under 10 KDa because of the characteristics of gel electrophoresis.

Objective: This study investigated biomarkers with molecular weight under 10 KDa in rats with arecoline challenge.

Materials and methods: The centrifuging vials with membrane (10 KDa molecular weight cut-off) played a crucial role in this study. After centrifuging, the filtrate (containing compounds with molecular weight under 10 KDa) was collected and spotted on a sample plate for MALDI-TOF mass spectrometry analysis.

Results: Compared to control, three extra peaks (m/z values were 1553.1611, 1668.2097 and 1740.1832, respectively) were found in sera and two extra peaks were found in heart tissue samples (408.9719 and 524.9961, respectively). These small compounds should play important roles and may be potential biomarker candidates in rats with arecoline.

Discussion and conclusions: This study successfully reports a mass-based method for investigating biomarker candidates with small molecular weight in different types of sample (including serum and tissue). In addition, this reported method is more time-efficient (1 working day) than gel-based proteomics approach (5~7 working days).     

槟榔提取液诱发大鼠口腔粘膜下纤维性变的实验研究 Ⅰ.组织形态学观察

采用粘膜下注射及表面涂布水溶性槟榔提取液（ＡＡＮＥ）相结合方法，诱发ＳＤ大鼠颊部口腔粘膜下纤维性变（ＯＳＦ）。在实验第１２，１６，２２及２８周分别进行颊粘膜显微及超微结构观察。结果发现：模型组动物在各个时期均出现了不同程度的ＯＳＦ样改变，即：上皮萎缩，钉突变平或消失；固有层大量炎症细胞浸润，胶原纤维堆积，排列紊乱并玻璃样变；病变进一步发展可波及深部肌层。停止使用ＡＡＮＥ６周后，病变未见明显逆转。对照组未见明显的组织形态学改变。采用粘膜下注射及表面涂布ＡＡＮＥ相结合方法可快速诱发出大鼠颊部比较典型、稳定的ＯＳＦ模型。     

The diagnosis of Brazil nut allergy using history, skin prick tests, serum-specific immunoglobulin E and food challenges

BACKGROUND: Allergy to Brazil nut is a relatively common nut allergy and can be fatal. However, the evidence is lacking regarding the best approach to its diagnosis. OBJECTIVE: We sought to determine the relative merits of history, skin prick testing, measurement of serum-specific IgE and challenge in the diagnosis of Brazil nut allergy. METHODS: Fifty-six children and adults with a history of an allergic reaction to Brazil nut or evidence of sensitization were investigated by questionnaire (n=56), skin prick tests (SPTs) (n=53), measurement of serum-specific IgE to Brazil nut (n=54) and double-blind, placebo-controlled labial, and if necessary oral, challenges (n=19). RESULTS: Brazil nut allergy occurred in highly atopic individuals of any age with a strong family history of atopy. In 24 of 56 (43%), the history of an immediate reaction was sufficient to make a diagnosis with confidence and an oral challenge was considered unsafe. Of the 19 subjects undertaking the 'gold standard' test of a double-blind, placebo-controlled, food challenge, all six subjects with a SPT of at least 6 mm had a positive challenge and all three subjects with a SPT of 0 mm had a negative challenge. In the remaining 10 (53%) subjects, where SPT was between 1 and 5 mm and serum-specific IgE was less than 3.5 kU/L, an oral challenge was performed resulting in three positive and seven negative challenges. CONCLUSION: A combination of history, SPT and serum-specific IgE was adequate in achieving a diagnosis in the majority (77%) patients with suspected Brazil nut allergy. However, a doubtful history with SPT between 1 and 5 mm, or a serum-specific IgE less than 3.5 kU/L may require an oral challenge to help determine the risk of a Brazil nut allergic reaction.     

Interpretation of tests for nut allergy in one thousand patients, in relation to allergy or tolerance

BACKGROUND: Peanut and tree nut allergy are common, increasing in prevalence and the commonest food cause of anaphylaxis. In the USA, 7.8% are sensitized (have nut-specific IgE), but not all those sensitized are allergic. Lack of data makes interpretation of tests for nut-specific IgE difficult. OBJECTIVES: This is the first study to investigate the clinical significance of test results for peanut and tree nut allergy in allergic or tolerant patients. Findings are related to the severity of the allergy. METHOD: An observational study of 1000 children and adults allergic to at least one nut. History of reactions (severity graded) or tolerance to up to five nuts was obtained and skin prick test (SPT)/serum-specific IgE (CAP) performed. RESULTS: There was no correlation between SPT size and graded severity of worst reaction for all nuts combined or for peanut, hazelnut, almond and walnut. For CAP, there was no correlation for all nuts. Where patients tolerated a nut, 43% had positive SPT of 3-7 mm and 3% > or = 8 mm. For CAP, 35% were positive (0.35-14.99 kU/L) and 5% > or = 15 kU/L. In SPT range 3-7 mm, 54% were allergic and 46% were tolerant. There was poor concordance between SPT and CAP (66%). Of patients with a clear nut-allergic history, only 0.5% had negative SPT, but 22% negative CAP. CONCLUSIONS: Magnitude of SPT or CAP does not predict clinical severity, with no difference between minor urticaria and anaphylaxis. SPT is more reliable than CAP in confirming allergy. Forty-six per cent of those tolerant to a nut have positive tests > or = 3 mm (sensitized but not allergic). One cannot predict clinical reactivity from results in a wide 'grey area' of SPT 3-7 mm; 22% of negative CAPs are falsely reassuring and 40% of positive CAPs are misleading. This emphasizes the importance of the history. Understanding this is essential for accurate diagnosis. Patients with SPT > or = 8 mm and CAP > or = 15 kU/L were rarely tolerant so these levels are almost always (in > or = 95%) diagnostic.     

Development of an in vivo mouse model to study oral submucous fibrosis

BACKGROUND: Epidemiological data have shown an association of areca nut chewing with oral submucous fibrosis (OSF). Experimental evidence to confirm this has been limited. Fibrosis-promoting activity of areca nut was tested in an animal model. METHOD: Buccal mucosa of a group of 20 female BALB/c strain mice, 10-12 weeks of age, was treated twice daily 6 days per week with topical application of aqueous areca nut extracts for 300-600 days. A control group (n = 20) was treated with 50 mM NaCl. The influence of areca nut on the oral epithelium and connective tissue was recorded semiquantitatively by light microscopy. RESULTS: The areca nut-treated oral epithelium showed progressive changes in epithelial thickness leading to atrophy, increased cellularity of fibroblasts, fibrosis of connective tissue, focal infiltration of inflammatory cells and muscle atrophy. On killing after 600 days of treatment, the scores on cellularity, inflammation and muscle atrophy were significantly different to the control group (P = 0.03). CONCLUSION: The study provides further evidence that areca nut contributes to the development of OSF in treated animals. The model has the potential to test synergism of areca nut with other carcinogens and any therapeutic interventions.