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Large-scale efforts have been persistently undertaken for medical prophylaxis and treatment of COVID-19 disasters worldwide. A variety of novel viral spike protein-targeted vaccines have been extensively distributed for global inoculation based on accelerated approval. With concerns of emerging spike protein mutations, we revisited the early but inconclusive clinical interest in the repurposed combination of azithromycin (AZT) and zinc supplements with safety advantages. The aim of this study is to provide in vitro proof of concept for IκBα associated rapid and synergistic suppression of angiotensin-converting enzymes 2 (ACE2) following combination treatments with AZT plus zinc sulfate in two human airway cells with ACE2 expression, Calu-3 and H322M, representative cells of the human upper and lower airway origin respectively. Clinical timing of AZT combined with zinc is indicated based on suppression of the key cellular entry molecule, ACE2, of SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes a vast number of infections and fatalities worldwide. As the development and safety validation of effective vaccines are ongoing, drug repurposing is most efficient approach to search FDA approved agents against coronavirus disease 2019 (COVID-19). In the present study, we found that endogenous ACE2 expressions could be detected in H322M and Calu-3 cell lines, as well as their ACE2 mRNA and protein expressions were suppressed by pyrrolidine dithiocarbamate (PDTC), a NF-kappa B inhibitor, in dose- and time-dependent manners. Moreover, N-acetyl-cysteine (NAC) pretreatment reversed PDTC-induced ACE2 suppression, as well as the combined treatment of hydrogen peroxide and knockdown of p50 subunit of NF-kappa B by siRNA reduced ACE2 expression in H322M cells. In addition, anthelmintic drug triclabendazole and antiprotozoal drug emetine, repurposed drugs of NF-kappa B inhibitor, also inhibited ACE2 mRNA and protein expressions in H322M cells. Moreover, zinc supplement augmented the suppressive effects of triclabendazole and emetine on ACE2 suppression in H322M and Calu-3 cells. Taken together, these results indicate that ACE2 expression is modulated by reactive oxygen species (ROS) and NF-kappa B signal in human lung cell lines, and zinc combination with triclabendazole or emetine has the clinical potential for the prevention and treatment of COVID-19.

Large-scale efforts have been persistently undertaken for medical prophylaxis and treatment of COVID-19 disasters worldwide. A variety of novel viral spike protein-targeted vaccine preparations have recently been clinically distributed based on accelerated approval. We revisited the early but inconclusive clinical interest in the combination of azithromycin and zinc sulfate repurposing with safety advantages. In vitro proof of concept was provided for rapid and synergistic suppression of ACE2 expression following treatments in human airway cells, Calu-3 and H322M. The two representative ACE2-expressing human airway cells indicate the upper and lower respiratory tracts. Prophylactic and early therapeutic roles of azithromycin combined with zinc are proposed for virus cellular entry prevention potential bridging to effective antibody production.

Niclosamide is an FDA‑approved anthelmintic drug, and may elicit antineoplastic effects through direct STAT3 inhibition, which has been revealed in numerous human cancer cells. Chemotherapy is the standard treatment for advanced esophageal cancers, but also causes severe systemic side effects. The present study represents the first study evaluating the anticancer efficacy of niclosamide in esophageal cancers. Through western blot assay, it was demonstrated that niclosamide suppressed the STAT3 signaling pathway in esophageal adenocarcinoma cells (BE3) and esophageal squamous cell carcinoma cells (CE48T and CE81T). In addition, niclosamide inhibited cell proliferation as determined by 3‑(4,5‑dimethylthiazol‑2‑yl)‑5‑(3‑carboxymethoxyphenyl)‑ 2‑(4‑sulfophenyl)‑-2H‑tetrazolium)‑5‑(3‑carboxymethoxyphenyl)‑ 2‑(4‑sulfophenyl)‑2H‑tetrazolium (MTS) assay and soft agar colony forming assay, and induced cell apoptosis as determined by Annexin V and PI staining. The induction of p21 and G1 arrest of the cell cycle also was revealed in niclosamide‑treated CE81T cells by qPCR and flow cytometric assays, respectively. Furthermore, in the combination analysis of niclosamide and chemotherapeutic agents by MTS assay, low IC50 values were detected in cells co‑treated with niclosamide, with the exception of cisplatin‑treated CE81T cells. To confirm the results using an apoptosis assay, the apoptotic enhancement of niclosamide was only demonstrated in CE48T cells co‑treated with 5‑FU, cisplatin, or paclitaxel, and in BE3 cells co‑treated with paclitaxel, but not in CE81T cells. These findings indicate a future clinical application of niclosamide in esophageal cancers.

Background The empiric therapies for H. pylori infection in clinical guidelines have been widely used. However, the cure rate is decreasing due to the increase of antibiotic resistance. The importance of antimicrobial susceptibility test (AST) has been documented in many consensuses. However, the effect of tailored therapy remains controversial because the AST is rarely offered in most areas. We compared the evolution of treatment efficacy among tailored therapy and some recommended empiric therapies through a trend survey from 1999 to 2018. Methods This retrospective survey was performed at 2 medical centers and 3 community hospitals in Taiwan. A total of 16,370 treatment naive or failure patients were recruited. Successful H. pylori eradication was defined as a negative 13C-UBT. The empiric first-line regimens include tailored therapy, clarithromycin-containing triple therapy (CLA-TT), sequential therapy (ST), bismuth-containing quadruple therapy (BQT), and high-dose dual therapy (HDDT). The empiric rescue regimens include tailored therapy, levofloxacin-containing triple therapy (LEV-TT), BQT, and HDDT. We divided the 20 years of follow-up time into 4-year periods for evaluating the trend of treatment efficacies. The E-test was performed to evaluate H. pylori resistance. For the tailored therapy, CLA-TT, LEV-TT, BQT, or HDDT was chosen according to the resistance pattern of each patient. Results The efficacies of tailored therapy, BQT, and HDDT maintain a stable and high efficacy in both first-line and rescue treatment during the study period. However, the efficacies of CLA-TT, ST, and LEV-TT are decreasing year by year. The eradication rate of tailored therapy is significantly higher than that of CLA-TT, ST, LEV-TT, and BQT in recent 4-year period. However, there is no significant difference between the efficacy of tailored therapy and HDDT. The prevalence of H. pylori resistance to CLA and LEV increased gradually. In contrast, the resistance rate to amoxicillin and tetracycline remained low. Conclusions Over the past 20 years, we found that the efficacy of tailored therapy remains relatively stable. Of the recommended empiric therapies, HDDT and BQT have stable therapeutic efficacies and are a good choice of empiric treatment currently.

Aims Angiotensin-converting enzyme 2 (ACE2) is a key negative regulator of the renin-angiotensin system and also a major receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Here, we reveal a role for NF-κB in human lung cell expression of ACE2, and we further explore the potential utility of repurposing NF-κB inhibitors to downregulate ACE2. Main methods Expression of ACE2 was assessed by Western blotting and RT-qPCR in multiple human lung cell lines with or without NF-κB inhibitor treatment. Surface ACE2 expression and intracellular reactive oxygen species (ROS) levels were measured with flow cytometry. p50 was knocked down with siRNA. Cytotoxicity was monitored by PARP cleavage and MTS assay. Key findings Pyrrolidine dithiocarbamate (PDTC), an NF-κB inhibitor, suppressed endogenous ACE2 mRNA and protein expression in H322M and Calu-3 cells. The ROS level in H322M cells was increased after PDTC treatment, and pretreatment with N-acetyl-cysteine (NAC) reversed PDTC-induced ACE2 suppression. Meanwhile, treatment with hydrogen peroxide augmented ACE2 suppression in H322M cells with p50 knockdown. Two repurposed NF-κB inhibitors, the anthelmintic drug triclabendazole and the antiprotozoal drug emetine, also reduced ACE2 mRNA and protein levels. Moreover, zinc supplementation augmented the suppressive effects of triclabendazole and emetine on ACE2 expression in H322M and Calu-3 cells. Significance These results suggest that ACE2 expression is modulated by ROS and NF-κB signaling in human lung cells, and the combination of zinc with triclabendazole or emetine shows promise for clinical treatment of ACE2-related disease.

Platelets play crucial roles in thrombosis and hemostasis through platelet activation and aggregation that are crucial in cardiovascular diseases. Hydroquinone (HQ) and its derivatives are present in many dermatological creams, paints, motor fuels, air, microorganisms, and plant products like wheat bread, fruit, coffee, and red wine. The effect of HQ on humans is not clear. In this study, we found that HQ (>25 μM) inhibited arachidonic acid (AA)-induced platelet aggregation. HQ suppressed AA-induced thromboxane B2 production of platelets. HQ (>10 μM) also attenuated ex vivo platelet-rich plasma aggregation. HQ prevented the interleukin (IL)-1β-induced 8-isoprostane, and PGE2 production, but not IL-8 production of pulp cells. These results indicate that HQ may have an antiplatelet effect via inhibition of thromboxane production. HQ has antioxidative and anti-inflammatory effects, and possible inhibition of COX. Exposure and consumption of HQ-containing products, food or drugs may have antiplatelet, antioxidative, and anti-inflammatory effects.

Inflammation and oxidative stress contribute to liver injury. Amla (Emblica officinalis Gaertn.) is rich in vitamin C, gallic acid, flavonoids, and tannins, which may protect against hepatoxicity-induced liver injury. We elucidated the effects of supplementary Amla (100 mg/kg of body weight) on N-nitrosodiethylamine-induced injury by evaluating reactive oxygen species (ROS) responses in the liver and bile, the degree of accumulated leukocytes and Kupffer cell infiltration, 3-nitrotyrosine and 4-hydroxynonenal stains, apoptosis and autophagy, plasma aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyl transpeptidase (γ-GT) levels, and antioxidant/oxidant enzymes in rats. Amla was more potent than vitamin C in scavenging O₂⁻·, hydrogen peroxide, and nitric oxide. N-Nitrosodiethylamine increased ROS production in liver and bile, hepatic Kupffer cell and leukocyte infiltration, 3-nitrotyrosine and 4-hydroxynonenal accumulations, apoptosis and autophagy, and plasma ALT, AST, and γ-GT levels in the rats, decreased hepatic manganese superoxide dismutase (MnSOD) and catalase protein expressions, and enhanced inducible nitric oxide synthase (iNOS) and cytochrome P450 2E1 (CYP2E1) protein expressions. Amla significantly preserved MnSOD and catalase expressions and decreased iNOS and CYP2E1 protein expressions in N-nitrosodiethylamine-treated livers. Amla decreased N-nitrosodiethylamine-enhanced hepatic apoptosis and autophagy appearances via down-regulation of the Bax/Bcl-2 ratio and Beclin-1 expression. Thus Amla supplementation counteracts N-nitrosodiethylamine-induced liver injury via its antioxidant, anti-inflammation, anti-apoptosis, and anti-autophagy properties.

Study Objective. To determine the factors that may influence Helicobacter pylori eradication in patients receiving omeprazole-amoxicillin dual therapy. Design. Prospective, randomized study. Setting. University-affiliated hospital in Taiwan. Patients. A total of 128 adults (age range 20–75 yrs) with H. pylori-positive duodenal ulcer were enrolled; 121 completed the final evaluation. Intervention. Patients were randomly assigned to one of four omeprazole-amoxicillin treatment groups, with each treatment administered for 2 weeks: O2A2 group (33 patients)—omeprazole 20 mg twice/day plus amoxicillin 500 mg 4 times/day; O2A1 group (32 patients)—omeprazole 20 mg twice/day plus amoxicillin 250 mg 4 times/day; O1A2 group (32 patients)—omeprazole 20 mg once/day plus amoxicillin 500 mg 4 times/day; and O1A1 group (31 patients)—omeprazole 20 mg once/day plus amoxicillin 250 mg 4 times/day Measurements and Main Results. Data were collected on H. pylori status, histologic parameters, antibiotic resistance, intragastric pH, cytochrome P450 (CYP) 2C19 genotype, and adverse reactions. The intent-to-treat cure rates (95% confidence interval [CI]) in groups O2A2, O2A1, O1A2, and O1A1 were 76% (95% CI 59–87%), 72% (95% CI 54–84%), 50% (95% CI 34–66%) and 52% (95% CI 35–68%), respectively. Eradication of H pylori infection was statistically significantly dependent on omeprazole dosage, CYP2C19 genotype, age, gastritis status, and H. pylori density. All CYP2C19 poor metabolizers were cured, whereas the H pylori cure rate in CYP2C19 extensive metabolizers varied from 44–76% in the different treatment groups. Eradication of H. pylori was favored in the omeprazole higher dose groups versus the lower dose groups (79% vs 53%, p=0.004). No secondary antibiotic resistance was found. Thirty-seven (95%) of 39 patients who failed with the initial treatment were cured by subsequent antibiotic susceptibility-driven proton pump inhibitor-based triple therapy. Conclusion. Provided a maintenance dose of amoxicillin is given every 6 hours, eradication of H pylori infection was significantly dependent on omeprazole dosage, CYP2C19 genotype, age, gastritis status, and H pylori density.

Chang MC, Chen YJ, Lee MY, Lin LD, Wang TM, Chan CP, Tsai YL, Wang CY, Lin BR, Jeng JH. Prostaglandin F2α stimulates MEK-ERK signalling but decreases the expression of alkaline phosphatase in dental pulp cells. International Endodontic Journal, 43, 461–468, 2010. Abstract Aim To study prostaglandin F2α (PGF2α) receptor expression and downstream signalling in cultured human dental pulp cells and the effect of PGF2α on the alkaline phosphatase (ALP) activity of dental pulp cells. Methodology Human dental pulp cells were cultured and exposed to PGF2α. The expression of PGF2α (FP) receptors was analysed by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting. The activation of extracellular regulated kinase (ERK) and cAMP responsive element binding protein/activating transcription factor-1 (CREB/ATF-1) signalling was determined by Western blotting. The expression of ALP in pulp cells after exposure to PGF2α was evaluated by ALP staining and PCR. Results Dental pulp cells expressed FP receptor mRNA and protein. Exposure to PGF2α revealed little cytotoxicity to pulp cells. PGF2α induced both ERK and CREB/ATF-1 phosphorylation in pulp cells. Exposure to PGF2α (>1 μmol L−1) further decreased the ALP activity and mRNA expression. However, U0126 (an inhibitor of MEK1) showed little preventive effect on the decline of ALP activity in dental pulp cells by PGF2α. Conclusion PGF2α may potentially activate FP receptors leading to ERK/CREB-ATF-1 activation during its production in inflamed dental pulp. PGF2α attenuated the ALP activity of pulp cells possibly via pathways not solely by MEK/ERK activation. PGF2α is a contributing factor of pulpal inflammation by regulating the activities of pulp cells.

Background: Tongue cancer metastasis is mainly through blood stream and possibly associated with tumor cell-induced platelet aggregation (TCIPA). Methods: Platelet aggregation was induced by different amounts of SAS tongue cancer cells with/without inhibitors and the latent period for induction of platelet aggregation was recorded. Gene expression was analyzed by reverse transcriptase-polymerase chain reaction. Results: SAS cells (4 × 104 to 1 × 106 cells/ml) induced platelet aggregation in a cell density-dependent manner. The latent period for induction of platelet aggregation reduced from 11.3 min (2 × 105 cells/ml) to 0.9 min (5 × 105 cells/ml). The extent of platelet aggregation increased from 39% to 76% by 2 × 105 and 5 × 105 SAS cells. Pre-treatment of SAS cells with aspirin showed little effect on its induction of platelet aggregation. SAS cells expressed tissue factor (TF) mRNA and the SAS cells-induced TCIPA was inhibited by TF neutralization antibody (5–20 μg/ml), heparin (5–10 U/ml), Hirudin fragment 54–65 (50 μg/ml) and D-Phenylalanyl-L-prolyl-L-arginine chloromethyl ketone. But areca nut (AN, a betel quid component known to generate reactive oxygen species (ROS)) extract showed little effect on TF expression in SAS cells. Pre-treatment with U73122 and 2-aminoethoxydiphenylborate inhibited SAS-induced TCIPA. Interestingly, catalase suppressed SAS cells-induced TCIPA, whereas AN extract enhanced this event. Conclusions: These results suggest that tongue cancer cells may induce TCIPA and enhance tumor metastasis. SAS-induced TCIPA is related to TF secretion, thrombin generation and associated with Phospholipase C-Inositol triphosphate signaling and ROS production. Betel quid chewing may potentially promote tongue cancer metastasis.

Background and Aim: Endoluminal gastroplication (ELGP) offers a minimally invasive option for the treatment of gastroesophageal reflux disease (GERD) in Western countries. However, long-term outcomes of ELGP in Asian populations have not been investigated. The aim of this prospective study was to evaluate the long-term benefits of ELGP in Asian patients with GERD. Methods: Taiwanese patients diagnosed with GERD were enrolled and had the procedure performed with EndoCinch. The assessment included symptom scoring, validated GERD questionnaires, esophagogastroduodenoscopy, esophageal manometry and 24-h pH monitoring before and after the procedure over a 2-year period. Results: Twenty-one consecutive patients were recruited and underwent ELGP. Patients reported improved heartburn symptom score (mean 64.0 vs 21.1, P

Background and purpose: Platelet hyperactivity is important in the pathogenesis of cardiovascular diseases. Betel leaf (PBL) is consumed by 200-600 million betel quid chewers in the world. Hydroxychavicol (HC), a betel leaf component, was tested for its antiplatelet effect. Experimental approach: We tested the effect of HC on platelet aggregation, thromboxane B2 (TXB2) and reactive oxygen species (ROS) production, cyclooxygenase (COX) activity, ex vivo platelet aggregation and mouse bleeding time and platelet plug formation in vivo. The pharmacokinetics of HC in rats was also assessed. Key results: HC inhibited arachidonic acid (AA) and collagen-induced platelet aggregation and TXB2 production. HC inhibited the thrombin-induced TXB2 production, but not platelet aggregation. SQ29548, suppressed collagen- and thrombin-induced TXB2 production, but not thrombin-induced platelet aggregation. HC also suppressed COX-1/COX-2 enzyme activity and the AA-induced ROS production and Ca2+ mobilization. HC further inhibited the ex vivo platelet aggregation of platelet-rich plasma (>100 nmole/mouse) and prolonged platelet plug formation (>300 nmole/mouse) in mesenteric microvessels, but showed little effect on bleeding time in mouse tail. Moreover, pharmacokinetics analysis found that more than 99% of HC was metabolized within 3 min of administration in Sprague-Dawley rats in vivo. Conclusions and implications: HC is a potent COX-1/COX-2 inhibitor, ROS scavenger and inhibits platelet calcium signaling, TXB2 production and aggregation. HC could be a potential therapeutic agent for prevention and treatment of atherosclerosis and other cardiovascular diseases through its anti-inflammatory and antiplatelet effects, without effects on haemostatic functions. British Journal of Pharmacology (2007) 152, 73–82; doi:10.1038/sj.bjp.0707367

Sanguinarine is a plant alkaloid present in the root of Sanguinaria canadensis and Poppy fumaria species. Sanguinarine has been used as an antiseptic mouth rinse and a toothpaste additive to reduce dental plaque and gingival inflammation. In this study, we investigated the antiplatelet effects of sanguinarine, aiming to extend its potential pharmacological applications. Sanguinarine inhibited platelet aggregation induced by arachidonic acid (AA), collagen, U46619 and sub-threshold concentration of thrombin (0.05 U/ml) with IC(50) concentrations of 8.3, 7.7, 8.6 and 4.4 microM, respectively. Sanguinarine (5-10 microM) inhibited 10-31% of platelet TXB(2) production, but not platelet aggregation induced by higher concentration of thrombin (0.1 U/ml). SQ29548, a thromboxane receptor antagonist, inhibited the AA-induced platelet aggregation but not TXB(2) production. Sanguinarine suppressed cyclooxygenase-1 (COX-1) activity (IC(50)=28 microM), whereas its effect on COX-2 activity was minimal. Sanguinarine (8, 10 microM) further inhibited the AA-induced Ca(2+) mobilization by 27-62%. In addition, SQ22536, an adenylate cyclase inhibitor, attenuated the inhibitory effect of sanguinarine toward AA-induced platelet Ca(2+) mobilization and aggregation. These results suggest that sanguinarine is a potent antiplatelet agent, which activates adenylate cyclase, inhibits platelet Ca(2+) mobilization, TXB(2) production as well as suppresses COX-1 enzyme activity. Sanguinarine may have therapeutic potential for treatment of cardiovascular diseases related to platelet aggregation.

Objective: Gastroesophageal flap valve (GEFV) grade predicts severe gastroesophageal reflux disease in Caucasians, but its role in other populations is unclear. This study evaluated the significance of endoscopic grading of the GEFV in Taiwanese subjects. Methods: Five hundred and six consecutive patients undergoing routine check-ups at the National Taiwan University Hospital were enrolled. Symptoms of upper gastrointestinal disease and endoscopic severity of esophageal mucosal injury were correlated to GEFV grades according to the Hill classification. Results: The frequency of abnormal valves (Hill grades III or IV) was 27.3%. Of these, 42.7% had erosive esophagitis (EE). The majority of patients with EE were classified as Los Angeles grades A and B (79.7 and 16.9%, respectively). The prevalence of EE, hiatal hernia and, to a lesser degree, non-erosive reflux disease, increased with altered GEFV. Patients with abnormal valves were younger and more likely to be male, overweight, and to have atypical and extraesophageal symptoms. Conclusions: Taiwanese patients with abnormal GEFVs share similar characteristics and risk factors with the patients who have EE. Endoscopic grading of the GEFV is highly associated with GERD, and in particular EE, in subjects undergoing routine endoscopy.

Increased hepatic sympathetic activity affects hepatic metabolism and hemodynamics and subsequently causes acute hepatic injury. We examined whether the vesicovascular reflex evoked by bladder overdistension could affect hepatic function, specifically reactive oxygen species (ROS)-induced inflammation and apoptosis, through activation of the hepatic sympathetic nerve. We evaluated the hepatic hemodynamics, hepatic sympathetic nervous activities, and cystometrograms in anesthetized rats subjected to acute urinary retention. We used a chemiluminescence method, an in situ nitro blue tetrazolium perfusion technique, and a DNA fragmentation/apoptosis-related protein assay to demonstrate de novo and colocalize superoxide production and apoptosis formation in rat liver. Acute urinary retention increased the hepatic sympathetic-dependent vesicovascular reflex, which caused hepatic vasoconstriction/hypoxia and increased superoxide anion production from the periportal Kupffer cells and hepatocytes, which were aggravated by the increase in volume and duration of urinary retention. The ROS-enhanced proinflammatory NF-κB, activator protein-1, and ICAM-1 expression also promoted proapoptotic mechanisms, including increases in the Bax/Bcl-2 ratio, CPP32 expression, poly-(ADP-ribose)-polymerase cleavages, and DNA fragmentation and apoptotic cells in the liver. The proinflammatory and proapoptotic mechanisms were significantly attenuated in rats treated with hepatic sympathetic nerve denervation or catechin (antioxidant) supplement. In conclusion, our results suggest that acute urine retention enhances hepatic sympathetic activity, which causes hepatic vasoconstriction and evokes proinflammatory and proapoptotic oxidative injury in the rat liver. Reduction of the hepatic sympathetic tone or antioxidant supplement significantly attenuates these injuries.

Cresol is a well-known environmental pollutant, toluene metabolite, uremic toxicant and accidental poisoning product. Formocresol, a preparation of formalin and cresol, is also used as a root canal medicament and for pulpotomy of primary teeth. However, little is known about its effect on cardiovascular system. In this study, m-cresol inhibited the AA-induced platelet aggregation by 43-97% at concentrations ranging from 0.25 to 1 mM. Collagen-induced platelet aggregation was also inhibited by 0.25-1 mM of m-cresol by 47-98%. Accordingly, o-cresol (0.1-0.5 mM) also inhibited the AA-induced platelet aggregation by 46-96% and the collagen-induced platelet aggregation by 35-88% at concentrations of 0.1-1 mM. AA- and collagen-induced platelet thromboxane B(2) (TXB(2)) production was inhibited by even 0.1 mM of m-cresol with 88 and 54% of inhibition, respectively. The o-cresol (0.1 mM) also inhibited the AA- and collagen-induced platelet TXB(2) production with 91 and 97% respectively. Although m- and o-cresol (

There are 2 to 6 billion betel quid (BQ) chewers in the world. Areca nut (AN), a BQ component, modulates arachidonic acid (AA) metabolism, which is crucial for platelet function. AN extract (1 and 2 mg/ml) stimulated rabbit platelet aggregation, with induction of thromboxane B2 (TXB2) production. Contrastingly, Piper betle leaf (PBL) extract inhibited AA-, collagen-, and U46619-induced platelet aggregation, and TXB2 and prostaglandin-D2 (PGD2) production. PBL extract also inhibited platelet TXB2 and PGD2 production triggered by thrombin, platelet activating factor (PAF), and adenosine diphosphate (ADP), whereas little effect on platelet aggregation was noted. Moreover, PBL is a scavenger of O2(*-) and *OH, and inhibits xanthine oxidase activity and the (*)OH-induced PUC18 DNA breaks. Deferoxamine, 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) and neomycin prevented AN-induced platelet aggregation and TXB2 production. Indomethacin, genistein, and PBL extract inhibited only TXB2 production, but not platelet aggregation. Catalase, superoxide dismutase, and dimethylthiourea (DMT) showed little effect on AN-induced platelet aggregation, whereas catalase and DMT inhibited the AN-induced TXB2 production. These results suggest that AN-induced platelet aggregation is associated with iron-mediated reactive oxygen species production, calcium mobilization, phospholipase C activation, and TXB2 production. PBL inhibited platelet aggregation via both its antioxidative effects and effects on TXB2 and PGD2 production. Effects of AN and PBL on platelet aggregation and AA metabolism is crucial for platelet activation in the oral mucosa and cardiovascular system in BQ chewers.

Background: Studies assessing the efficacy of triple therapy containing clarithromycin and amoxicillin for the eradication of Helicobacter pylori infection and healing of duodenal ulcers in Asian and African countries are limited. Aim: To determine the efficacy and safety of 1-week triple therapy with omeprazole, amoxicillin and clarithromycin for eradicating H. pylori infection in patients with active duodenal ulcer living in Asian and African regions. Methods: This was an open-label, multicentre study in 11 centres in Asia and Africa. Patients with endoscopy-proven duodenal ulcer and who were H. pylori-positive were treated with clarithromycin 500 mg, omeprazole 20 mg, and amoxicillin 1000 mg, all given twice daily for 7 days. Upper endoscopy was repeated at week 6 to check for ulcer healing and H. pylori status. Results: A total of 117 patients were recruited. H. pylori eradication rates were 85% by per protocol analysis and 80% by intention-to-treat analysis. Ulcer healing was found in 94% of subjects (per protocol analysis). Clinical success, measured by change of pre-treatment ulcer symptoms, was strongly supported by complete resolution or improvement in 100% of the evaluable patients (per protocol analysis). Since treatment-related adverse events, when present, were largely mild or moderate, the triple therapy regimen was considered safe. Conclusion: Seven-day triple therapy with omeprazole, amoxicillin, and clarithromycin was efficacious for treating Asian and African patients with duodenal ulcer disease associated with H. pylori infection, and the treatment regimen was well-tolerated.

One newly bred variety of tea cultivar, purple-shoot tea, was selected to evaluate its antiproliferative effects on colorectal carcinoma cells, as well as normal colon cells. The phytochemicals and identified catechins of purple-shoot tea extract (PTE) were significantly higher than that of ordinary tea, especially the anthocyanins (surpassed by 135-fold) and anthocyanidins (surpassed by 3.5-fold). PTE inhibited the proliferation of COLO 320DM (IC(50) = 64.9 μg/mL) and HT-29 (IC(50) = 55.2 μg/mL) by blocking cell cycle progression during the G(0)/G(1) phase and inducing apoptotic death. Western blotting indicated that PTE induced cell cycle arrest by reducing the expression of cyclin E and cyclin D1 in COLO 320DM and the upregulation of p21 and p27 cyclin-dependent kinase inhibitors in HT-29. Two cells treated with PTE also indicated the cleavage of PARP, activation of caspase 3, and an increased Bax/Bcl-2 ratio. Our results showed that PTE is a potential novel dietary agent for colorectal cancer chemoprevention.

Objective: Gut barrier dysfunction and bacterial translocation occur in various disorders, including intestinal obstruction. Overexpression of inducible nitric oxide synthase is implicated in the pathogenesis of bacterial translocation, of which the molecular mechanism remains unclear. Epithelial permeability is regulated by tight junction reorganization and myosin light chain phosphorylation. Our aim was to investigate the roles of Rho-associated kinase and protein kinase C in epithelial nitric oxide synthasemediated barrier damage. Design: Animal study and cell cultures. Setting: Research laboratory. Subjects: BALB/c mice. Interventions: Mouse distal small intestine was obstructed in vivo by a 10-cm loop ligation in which vehicle, L-Nil (a nitric oxide synthase inhibitor), or Y27632 (a Rho-associated kinase inhibitor) was luminally administered. After obstruction for 24 hrs, intestinal tissues were mounted on Ussing chambers for macromolecular flux. Liver and spleen tissues were assessed for bacterial counts. Caco-2 cells were exposed to 1 mM S-nitroso-Nacetylpenicillamine (a nitric oxide donor) for 24 hrs, and transepithelial resistance and permeability were evaluated. Measurements and Main Results: Mice with intestinal obstruction displayed epithelial barrier dysfunctions, such as permeability rise and bacterial translocation, associated with tight junction disruption and myosin light chain phosphorylation. Increased inducible nitric oxide synthase and phosphorylated protein kinase C were observed in villus epithelium. Enteric instillation of L-Nil and Y27632 attenuated the functional and structural barrier damage caused by intestinal obstruction. L-Nil decreased intestinal obstruction-induced myosin light chain, myosin phosphatase target subunit 1, and protein kinase C phosphorylation, suggesting that inducible nitric oxide synthase is upstream of Rho-associated kinase and protein kinase C signaling. The intestinal phosphorylated myosin light chain level did not increase in inducible nitric oxide synthase(-/-) mice following intestinal obstruction. In vitro studies showed that S-nitroso-N-acetylpenicillamine-induced transepithelial resistance drop and permeability rise was independent of cell apoptosis. Y27632 inhibited S-nitroso-N-acetylpenicillamine-induced myosin light chain phosphorylation and permeability rise. S-nitroso-N-acetylpenicillamine also triggered phosphorylation and membrane translocation of protein kinase C . Inhibitory protein kinase C pseudosubstrate blocked S-nitroso-N-acetylpenicillamine-induced tight junction reorganization, but not myosin light chain phosphorylation. Conclusions: Epithelial inducible nitric oxide synthase activates two distinct signals, protein kinase C and Rho-associated kinase, to disrupt tight junctions leading to bacterial influx. (Crit Care Med 2011; 39:000‐000)

P-cresol is a well-known uremic toxin and environmental toxicant that may affect platelet functions. In this study, p-cresol (1-5 μM) inhibited the arachidonic acid (AA)-induced platelet aggregation, with 47% and 82% of inhibition at concentrations of 2 and 5 μM, respectively. Under similar experimental condition, p-cresol showed little effect on the U46619-induced platelet aggregation. p-cresol (

Tongue cancer metastasis is mainly through blood stream and possibly associated with tumor cell-induced platelet aggregation (TCIPA).Platelet aggregation was induced by different amounts of SAS tongue cancer cells with/without inhibitors and the latent period for induction of platelet aggregation was recorded. Gene expression was analyzed by reverse transcriptase-polymerase chain reaction.SAS cells (4 x 10(4) to 1 x 10(6) cells/ml) induced platelet aggregation in a cell density-dependent manner. The latent period for induction of platelet aggregation reduced from 11.3 min (2 x 10(5) cells/ml) to 0.9 min (5 x 10(5) cells/ml). The extent of platelet aggregation increased from 39% to 76% by 2 x 10(5) and 5 x 10(5) SAS cells. Pre-treatment of SAS cells with aspirin showed little effect on its induction of platelet aggregation. SAS cells expressed tissue factor (TF) mRNA and the SAS cells-induced TCIPA was inhibited by TF neutralization antibody (5-20 microg/ml), heparin (5-10 U/ml), Hirudin fragment 54-65 (50 microg/ml) and D-Phenylalanyl-L-prolyl-L-arginine chloromethyl ketone. But areca nut (AN, a betel quid component known to generate reactive oxygen species (ROS)) extract showed little effect on TF expression in SAS cells. Pre-treatment with U73122 and 2-aminoethoxydiphenylborate inhibited SAS-induced TCIPA. Interestingly, catalase suppressed SAS cells-induced TCIPA, whereas AN extract enhanced this event.These results suggest that tongue cancer cells may induce TCIPA and enhance tumor metastasis. SAS-induced TCIPA is related to TF secretion, thrombin generation and associated with Phospholipase C-Inositol triphosphate signaling and ROS production. Betel quid chewing may potentially promote tongue cancer metastasis.

Background & Aims The efficacy of treatment of Helicobacter pylori infection has decreased steadily because of increasing resistance to clarithromycin, metronidazole, and levofloxacin. Resistance to amoxicillin is generally low, and high intragastric pH increases the efficacy of amoxicillin, so we investigated whether a combination of a high-dose proton pump inhibitor and amoxicillin (dual therapy) was more effective than standard first-line or rescue therapies in eradicating H pylori . Methods We performed a large-scale multihospital trial to compare the efficacy of a high-dose dual therapy (HDDT) with that of standard therapies in treatment-naive (n = 450) or treatment-experienced (n = 168) patients with H pylori infection. Treatment-naive patients were randomly assigned to groups given HDDT (rabeprazole 20 mg and amoxicillin 750 mg, 4 times/day for 14 days, group A1), sequential therapy for 10 days (group B1), or clarithromycin-containing triple therapy for 7 days (group C1). Treatment-experienced patients were randomly assigned to groups given HDDT for 14 days (group A2), sequential therapy for 10 days (B2), or levofloxacin-containing triple therapy for 7 days (C2). H pylori infection was detected by using the 13 C-urea breath test. We evaluated factors associated with treatment outcomes. Results In the intention-to-treat analysis, H pylori was eradicated in 95.3% of patients in group A1 (95% confidence interval [CI], 91.9%−98.8%), 85.3% in B1 (95% CI, 79.6%−91.1%), and 80.7% in group C1 (95% CI, 74.3%−87.1%). Infection was eradicated in 89.3% of patients in group A2 (95% CI, 80.9%−97.6%), 51.8% in group B2 (95% CI, 38.3%−65.3%), and 78.6% (95% CI, 67.5%−89.7%) in group C2. The efficacy of HDDT was significantly higher than that of currently recommended regimens, irrespective of CYP2C19 genotype. Bacterial resistance to drugs was associated with treatment failure. There were no significant differences between groups in adverse events or patient adherence. Conclusions HDDT is superior to standard regimens as empirical first-line or rescue therapy for H pylori infection, with similar safety profiles and tolerability. ClinicalTrials.gov number: NCT01163435.

Background: The increased primary and acquired resistance rates of H. pylori to clarithromycin, metronidazole, and levofloxacin have resulted in a significant reduction in the efficacy of various anti-H. pylori regimens. We recently demonstrated that an optimized high-dose dual therapy (HDDT) is superior to the standard triple therapy (TT) or sequential therapy (ST) for H. pylori infection in a large-scale multi-hospital, randomized, comparative study (Clinical Gastro & Hepato, in press). Because the global prevalence of primary and acquired resistance to amoxicillin (AMO) is rare, we hypothesize that HDDT can be used repeatedly and empirically for H. pylori treatment without a reduction of eradication efficacy. Aim: To evaluated the cumulative efficacy of repeated HDDT treatment for first-line and rescue antiH. pylori therapy. Methods: A total of 618 patients with H. pylori infection diagnosed by endoscopy with biopsy for histology examination and bacterial culture were recruited in this multi-hospital study and were randomly allocated to receive HDDT, TT, or ST for therapy. As reported in our previous study, H. pylori was eradicated in 143 out of 150 (95.3%; 95% C.I. 92.9-97.8) treatment-naive patients receiving the first course of HDDT (rabeprazole 20 mg + AMO 750 mg, qid for 14 days). Six patients who failed in the first HDDT treatment received the second course of HDDT. For treatment-experienced patients, 68 out of 84 patients failed in TT and 25 out of 45 patients failed in ST received the first course of HDDT. The second course of HDDT was used again if the first course failed. Four to eight weeks after termination of each treatment, H. pylori infection status was examined by the C13-urea breath test. The E-test was used to evaluate the antibiotics resistances of H. pylori strains before and after failed treatment of repeated HDDT. Results: Five out of 6 treatment-naive patients had successfully H. pylori eradication by a second course of HDDT, resulting in a cumulative eradication rate of 98.7% (148/150; 95% C.I. 97.3-100.0) in the intention-to-treat (ITT) analysis, and 99.3% (148/149; 95% C.I. 98.4-100.3) in perprotocol (PP) analysis. For the treatment-experienced patients, H. pylori was successfully eradicated in 90.3% (84/93; 95% C.I. 85.9-94.7) of patients with first course of HDDT treatment. Seven out of 9 patients who failed in the first HDDT treatment achieved H. pylori eradication with a second course of HDDT. The cumulative eradication rate was 97.8% (91/ 93; 95% C.I. 95.7-100.0) in both ITT and PP analyses. The susceptibility of H. pylori to antibiotics did not significantly impact eradication rates. Conclusion: HDDT consisting of a PPI and AMO given four times daily is highly efficacious when it is used repeatedly for H. pylori eradication. Thus, H. pylori susceptibility testing may be avoided by using HDDT.

Sanguinarine is a benzopheanthridine alkaloid present in the root of Sanguinaria canadensis L. and Chellidonium majus L. In this study, sanguinarine (2 and 3 microM) exhibited cytotoxicity to KB cancer cells by decreasing MTT reduction to 83% and 52% of control after 24-h of exposure. Sanguinarine also inhibited the colony forming capacity (>52-58%) and growth of KB cancer cells at concentrations higher than 0.5-1 microM. Short-term exposure to sanguinarine (>0.5 microM) effectively suppressed the adhesion of KB cells to collagen and fibronectin (FN). Sanguinarine (2 and 3 microM) induced evident apoptosis as indicated by an increase in sub-G0/G1 populations, which was detected after 6-h of exposure. Only a slight increase in cells arresting in S-phase and G2/M was noted. Induction of KB cell apoptosis and necrosis by sanguinarine (2 and 3 microM) was further confirmed by Annexin V-PI dual staining flow cytometry and the presence of DNA fragmentation. The cytotoxicity by sanguinarine was accompanied by an increase in production of reactive oxygen species (ROS) and depolarization of mitochondrial membrane potential as indicated by single cell flow cytometric analysis of DCF and rhodamine fluorescence. NAC (1 and 3 mM) and catalase (2000 U/ml) prevented the sanguinarine-induced ROS production and cytotoxicity, whereas dimethylthiourea (DMT) showed no marked preventive effect. These results suggest that sanguinarine has anticarcinogenic properties with induction of ROS production and mitochondrial membrane depolarization, which mediate cancer cell death.

Lifestyle element evaluated: sodium butyrate. Outcome studied: toxic effect of sodium butyrate (cell cycle arrest, apoptosis and growth inhibition) in SAS tongue cancer cells; sodium butyrate-induced ROS production in SAS tongue cancer cells. Method of biomarker analysis: toxic effect of sodium butyrate on SAS cancer cells (growth of SAS cancer cells, cell cycle progression of SAS cancer cells); ROS production (Reactive oxygen species scavenging properties of sodium butyrate, effect of sodium butyrate on GSH and ROS levels in SAS cancer cells)Study type: Human tongue cancer cell line SAS Quality control: More than four separate experiments were performed for each test.Impact on outcome: Sodium butyrate inhibited the growth of SAS tongue cancer cells by 32% and 53% at concentrations of 1 and 2mM, respectively. Low concentrations of sodium butyrate (1-8mM) induced G0/G1 cell cycle arrest of SAS cells, whereas concentrations of 4-16 mM elicited G2/M arrest and a slight increase in apoptotic cell populations. These events were concomitant with induction of intracellular reactive oxygen species (ROS) production. An elevation in p21 mRNA and protein level was noted in SAS cells by sodium butyrate. On the contrary, a decline of cyclin Bl, cdc2 and cdc25C mRNA and protein expression in SAS cells was found after exposure to sodium butyrate. In addition, no evident increase in cdc2 inhibitory phosphorylation was found in sodium butyrate-treated SAS cancer cells. Inclusion of N-acetyl-l-cysteine (NAC) (3mM), catalase (1000 U/ml) and dimethylthiourea (DMT, 5mM), and also SOD (500 U/ml) attenuated the sodium butyrate-induced ROS production in SAS cells. However, they were not able to prevent the cell cycle arrest, apoptosis and growth inhibition in SAS cells induced by 1, 2 and 16 mM of sodium butyrate. KEYWORDS - CLASIFFICATION: analysis;Apoptosis;Butyrates;Cell Cycle;Cell Cycle Proteins;Cell Line,Tumor;drug effects;Free Radical Scavengers;Gene Expression;genetics;Human;Humans;lifestyle modulation of cancer & cancer biomarkers;mechanisms of carcinogenesis;metabolism;Oxidation-Reduction;pathology;pharmacology;Proteins;Reactive Oxygen Species;Research;Sodium;Taiwan;Tongue Neoplasms;Toxicology; Butyrate is a metabolite produced by oral and colonic microorganism. Butyrate has been shown to reduce colon cancer, whereas its role in oral carcinogenesis is not clear. Butyrate concentration in dental plaque and saliva ranged from 0.2 to 16 mM. In this study, we found that sodium butyrate inhibited the growth of SAS tongue cancer cells by 32% and 53% at concentrations of 1 and 2mM, respectively. Low concentrations of sodium butyrate (1-8mM) induced G0/G1 cell cycle arrest of SAS cells, whereas concentrations of 4-16 mM elicited G2/M arrest and a slight increase in apoptotic cell populations. These events were concomitant with induction of intracellular reactive oxygen species (ROS) production. An elevation in p21 mRNA and protein level was noted in SAS cells by sodium butyrate. On the contrary, a decline of cyclin Bl, cdc2 and cdc25C mRNA and protein expression in SAS cells was found after exposure to sodium butyrate. In addition, no evident increase in cdc2 inhibitory phosphorylation was found in sodium butyrate-treated SAS cancer cells. Inclusion of N-acetyl-l-cysteine (NAC) (3mM), catalase (1000 U/ml) and dimethylthiourea (DMT, 5mM), and also SOD (500 U/ml) attenuated the sodium butyrate-induced ROS production in SAS cells. However, they were not able to prevent the cell cycle arrest, apoptosis and growth inhibition in SAS cells induced by 1, 2 and 16 mM of sodium butyrate. These results indicate that sodium butyrate is toxic and inhibits the tongue cancer cell growth via induction of cell cycle arrest and apoptosis. Sodium butyrate mediates these events by mechanisms additional to ROS production.

Various root-end filling materials have been used to prevent the entry of root-canal pathogens into periapical regions. Five root-end filling materials were compared regarding the cytotoxicity, apoptosis, and mitochondrial dehydrogenase (MDH) activities of human periodontal ligament (PDL) fibroblasts, with the use of a novel transwell culture system. Exposure to IRM (a ZnO eugenol-based intermediate restorative material), a 2-ethoxybenzoic acid cement (Super EBA), and amalgam for 3 days inhibited the MDH activity of PDL fibroblasts as indicated by decrease in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) reduction by 97%, 95%, and 51%, respectively. Evident suppression of MTT reduction by amalgam and glass ionomer cement (GIC) was noted after 5 days of exposure, with 73% and 46% of inhibition, respectively. Mineral trioxide aggregates (MTA) showed little effect on MDH activity. IRM and Super EBA were cytotoxic to PDL fibroblasts as indicated by a trypan blue dye exclusion technique. GIC and amalgam showed mild cytotoxicity. IRM, GIC, and amalgam further induced apoptosis of PDL cells, as revealed by the presence of sub-G0/G1 DNA content in flow cytometric histogram. Twenty-four-hour exposure to IRM and Super EBA elevated the MDH activities to 156% and 117%, correspondingly, of that of control. Eugenol, a phenolic ingredient in Super EBA and IRM, also increases MDH activity of PDL fibroblasts by 45% and 51%, at concentrations of 0.5 and 1 mM. However, at concentrations higher than 0.5 mM, eugenol decreased the number of viable PDL fibroblasts. These results suggest that MTA is a biocompatible root-end filling material, followed by self-curing Fuji II GIC and amalgam. IRM and Super EBA ingredients induced marked cytotoxicity and transiently stimulate MDH activities, which is possibly due to their content of eugenol and induction of cellular adaptive response.

The predictive value of gastroesophageal reflux disease (GERD) symptoms for erosive esophagitis is controversial. This study evaluated the sensitivity of heartburn and acid regurgitation as indicators of erosive esophagitis in Taiwanese.Data collected from 521 consecutive health check-up participants who received panendoscopy and completed a self-administered questionnaire for GERD were analyzed. A classification system was used based on the presence of typical symptoms (heartburn or acid regurgitation) experienced 1 or more times per week (I), less than once per week, but more than once per month (II), and in the past (III), and in subjects free of typical symptoms, comprised those with atypical symptoms (IV), extraesophageal symptoms (V), both atypical and extraesophageal symptoms (VI), and lack of all of the above symptoms (VII). The Los Angeles classification was used for the endoscopic assessment of erosive esophagitis.The sensitivity, positive predictive value (PPV), and specificity of criteria I+II were 30.5%, 32%, and 78.9%, respectively, for erosive esophagitis in Taiwanese. Inclusion of symptoms in category III increased sensitivity by 13.3%. Combined symptoms in categories IV+V+VI had the highest negative predictive value of 85.5% and a fair specificity of 73.8% for those free of typical symptoms. In the overall classification system, the combination of symptoms in categories IV+V+VI increased sensitivity by 17.9 to 61.7%, and decreased specificity by 26.3 to 40.4%. The most specific indicator was symptoms in category I (with a PPV of 45% for erosive esophagitis in symptomatic patients). About two-fifths (38.3%) of patients with erosive esophagitis had none of the symptoms in the classification system.Heartburn and acid regurgitation are insensitive predictors of erosive esophagitis in Taiwanese. Step-wise addition of previous typical symptoms, currently atypical and extraesophageal symptoms to the "heartburn and acid regurgitation" criterion can greatly increase sensitivity, but endoscopy remains the method of choice to detect erosive esophagitis.

Piper betle, belonging to the Piperaceae family, is a tropical plant, and its leaf and inflorescence are popularly consumed by betel quid (BQ) chewers in Taiwan and many other South and Southeast Asian countries. However, little is known about the biochemical properties of inflorescence Piper betle (IPB) toward reactive oxygen species (ROS) and platelet functions. In the present work, aqueous IPB extract was shown to be a scavenger of H(2)O(2), superoxide radical, and hydroxyl radical with a 50% inhibitory concentration (IC(50)) of about 80, 28, and 73 microg/mL, respectively. IPB extract also prevented the hydroxyl radical induced PUC18 plasmid DNA breaks at concentrations higher than 40 microg/mL. Since ROS are crucial for platelet aggregation, we further found that IPB extract also inhibited the arachidonic acid (AA) induced and collagen-induced platelet aggregation, with an IC(50) of 207 and 335 microg/mL, respectively. IPB extract also inhibited the AA-, collagen- (100 microg/mL of IPB), and thrombin (250 microg/mL of IPB)-induced thromboxane B(2) (TXB(2)) production by more than 90%. However, IPB extract showed little effect on thrombin-induced aggregation. These results indicated that aqueous components of IPB are potential ROS scavengers and may prevent the platelet aggregation possibly via scavenging ROS or inhibition of TXB(2) production.

Betel quid (BQ) chewing has a strong correlation with oral leukoplakia, submucous fibrosis and oral cancer. For elucidation of its pathogenesis, we investigated the effects of areca nut (AN) and inflorescence piper betle (IPB) extracts and arecoline on the growth, total DNA synthesis (TDS) and unscheduled DNA synthesis (UDS) of cultured human gingival keratinocytes (GK). Arecoline and AN extract suppressed the growth of GK over 5 days of incubation in a dose-dependent fashion. At concentrations of 100, 200 and 400 microg/ml, AN extract suppressed the growth of GK by 31%, 46% and 90%, respectively. The IPB extracts exerted less inhibitory effect on the growth of GK. IPB extract (200-400 microg/ml) decreased cell numbers by 20-40% over 5 days of incubation. Moreover, at a concentration of 0.1, 0.2 and 0.4 mM, arecoline suppressed cell growth by 44%, 77% and 96%, respectively. However, only AN extract induced TDS and UDS in cultured GK within 6 h of exposure. Induction of UDS by AN extract was concomitant with the presence of apparent intracellular vacuolization. Arecoline was also toxic to GK, but did not induce intracellular vacuolization. At a concentration range of 200-1600 microg/ml, AN extract induced TDS by 2.1- to 6.5-fold. Furthermore, at a concentration of 400-1600 microg/ml, AN extract elevated the UDS by 2.4- to 5.5-fold more than that of untreated control. On the contrary, IPB extract (200-1600 microg/ml) and arecoline (0.2-1.6 mM) inhibited the TDS and UDS of GK to a different extent. Simultaneous exposure of confluent GK to AN extract, IPB extract and arecoline for 1 to 5 days led to different degrees of cytotoxicity that was dose- and time-dependent. These results indicate that AN, IPB and arecoline take part in the pathogenesis of BQ chewing-related oral mucosal lesions, possibly through both genotoxic and non-genotoxic mechanisms.

S1552 Endoscopic Surveillance of the Gastroesophageal Flap Valve Following Endoluminal Gastroplication in Patients with GERD Chien-Chung Liao, Bor-Ru Lin, Chia-Long Lee, Ivy L. Pike Background: Endoluminal gastroplication (ELGP) is a novel therapeutic option for the treatment of gastroesophageal reflux disease (GERD). The procedure seems to lessen or eliminate the hiatal space. An improvement of the gastroesophageal flap valve (GEFV) following ELGP was reported and was noted in most patients Abstracts

Curcumin (diferuloylmethane), a yellow substance from the root of the plant Curcuma longa Linn., has been demonstrated to inhibit carcinogenesis of murine skin, stomach, intestine and liver. However, the toxicology, pharmacokinetics and biologically effective dose of curcumin in humans have not been reported. This prospective phase-I study evaluated these issues of curcumin in patients with one of the following five high-risk conditions: 1) recently resected urinary bladder cancer; 2) arsenic Bowen's disease of the skin; 3) uterine cervical intraepithelial neoplasm (CIN); 4) oral leucoplakia; and 5) intestinal metaplasia of the stomach. Curcumin was taken orally for 3 months. Biopsy of the lesion sites was done immediately before and 3 months after starting curcumin treament. The starting dose was 500 mg/day. If no toxicityor = grade II was noted in at least 3 successive patients, the dose was then escalated to another level in the order of 1,000, 2,000, 4,000, 8,000, and 12,000 mg/day. The concentration of curcumin in serum and urine was determined by high pressure liquid chromatography (HPLC). A total of 25 patients were enrolled in this study. There was no treatment-related toxicity up to 8,000 mg/day. Beyond 8,000 mg/day, the bulky volume of the drug was unacceptable to the patients. The serum concentration of curcumin usually peaked at 1 to 2 hours after oral intake of crucumin and gradually declined within 12 hours. The average peak serum concentrations after taking 4,000 mg, 6,000 mg and 8,000 mg of curcumin were 0.51 +/- 0.11 microM, 0.63 +/- 0.06 microM and 1.77 +/- 1.87 microM, respectively. Urinary excretion of curcumin was undetectable. One of 4 patients with CIN and 1 of 7 patients with oral leucoplakia proceeded to develop frank malignancies in spite of curcumin treatment. In contrast, histologic improvement of precancerous lesions was seen in 1 out of 2 patients with recently resected bladder cancer, 2 out of 7 patients of oral leucoplakia, 1 out of 6 patients of intestinal metaplasia of the stomach, I out of 4 patients with CIN and 2 out of 6 patients with Bowen's disease. In conclusion, this study demonstrated that curcumin is not toxic to humans up to 8,000 mg/day when taken by mouth for 3 months. Our results also suggest a biologic effect of curcumin in the chemoprevention of cancer.