The modifying effects of dietary administration of a flavonoid antioxidant, silymarin, a mixture of three flavonoids isolated from milk thistle seeds, on N-butyl-N-(4-hydroxybutyl)nitrosamine (OH-BBN)-induced urinary bladder carcinogenesis were examined in male ICR mice. Animals were divided into 5 groups, and groups 1 to 3 were given OH-BBN (500 ppm) in drinking water for 6 weeks. Mice in group 2 were fed a diet containing 1000 ppm silymarin for 8 weeks during the initiation phase starting 1 week before OH-BBN exposure, and mice in group 3 were fed the diet for 24 weeks during the postinitiation phase. Animals in group 4 were given only the test compound, and those in group 5 were given the basal diet alone throughout the experiment. Animals were sacrificed at the end of week 32. The frequency of bladder lesions, cell proliferation and cell cycle progression activity estimated in terms of the 5-bromodeoxyuridine (BrdU) labeling index or cyclin D1-positive cell ratio were compared among the groups. Administration of silymarin in the initiation or postinitiation phase significantly decreased the incidences of bladder neoplasms and preneoplastic lesions. Dietary exposure to this agent significantly reduced the labeling index for BrdU and the cyclin D1-positive cell ratio in various bladder lesions. These findings suggest that silymarin is effective in preventing OH-BBN-induced bladder carcinogenesis in mice. Key words: Chemoprevention -Silymarin -OH-BBN -Cyclin D1 -Urinary bladder carcinogenesisThe incidence of bladder cancer has been increasing in most industrialized countries.1) In the United States, 50 500 new cases of the disease were recognized in 1995.2) In the light of the high incidence, increasing attention has been focused on the prevention of bladder cancer at the earliest possible stage.A recent approach to curb cancer incidence is chemopreventive intervention, through which the disease can be prevented totally, or slowed, or reversed partially or substantially by the administration of one or more naturally occurring or synthetic chemical agents. Fruit, vegetables, and beverages, as well as several herbs and plants with diverse pharmacological properties, have been shown to be rich sources of microchemicals with potential to prevent the occurrence of cancers.3-7) The chemopreventive potential of flavonoids in various organs has been established in vivo as well as in vitro. [8][9][10] Among flavonoids, silymarin, a mixture of three structural isomers (Fig. 1) is known to be present in milk thistle (Silybum marianum) seeds and is used clinically in Europe, Asia, and other countries basically for the treatment of liver disease. [11][12][13] It is well known that silymarin is capable of scavenging both free radicals and reactive oxygen species in rodents and in cell cultures.14-17) This agent is reported to abolish the lethal effects and pathological changes induced by microcystin-LR intoxication.18) In human studies, it was shown that serum transaminases and sulfobromophthalein retention in the silymarin-...

This paper is to present a space vector PWM algorithm for four switch three phase inverters (B4, FSTPI) based on the one for six switch three phase inverters (B6, SSTPI) (principle of similarity) where the cX plan is divided into 6 sectors and the formation of the required reference voltage space vector is done in the same way as for B6 by using effective (mean) vectors. This facilitates the calculation for B4 and some studies on B6 can be applied for B4 as well through this proposed similarity, e.g. the problem with PWM in the overmodulation zone due to the complicated non-linear character there. Matlab/ Simulink is used for the simulation of the proposed SVPWM algorithm for undermodulation, overmodulation mode 1 and 2. This SVPWM approach is also validated experimentally using control board TMS eZDSP2812 (Texas Instrument Co.).

The modifying effects of dietary administration of 1,4-phenylene diisothiocyanate (DITC) on N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN)-induced urinary bladder carcinogenesis during the initiation and post-initiation phases were examined in male ICR mice. Five-week-old animals were divided into 5 groups. Groups 1-3 were given BBN (500 ppm) in drinking water for 6 weeks starting at age 6 week. Mice in Group 2 were given the diet containing 100 ppm DITC for 8 weeks during the initiation phase, starting 1 week before BBN exposure. Animals in Group 3 were fed the experimental diet for 24 weeks during the post-initiation phase starting 1 week after the cessation of BBN exposure. Mice in Group 4 were given only the diet containing the test compound, and those in Group 5 were given the basal diet alone throughout the experiment (32 weeks). The frequency of bladder lesions, neoplasms, dysplasia and hyperplasia, was analyzed histopathologically. The cell-proliferation activity estimated by the 5-bromodeoxyuridine labeling index (BrdU-LI), and cell cycle progression by counting cyclin D1-positive cell ratios were compared among the groups using immunohistochemistry. Administration of DITC in the initiation phase reduced significantly the incidence of urinary bladder carcinoma and dysplasia. The frequencies of any lesions of urinary bladder were not reduced by DITC in post-initiation phase. Dietary exposure of this agent in initiation phase reduced significantly both BrdU-LI and cyclin D1-positive cell ratios in any bladder lesions. Administration of DITC in post-initiation phase also significantly reduced BrdU-LI in bladder neoplasms and hyperplasia and cyclin D1-positive cell ratios in urinary bladder carcinoma as well as dysplasia. These results suggest that dietary DITC could be a preventive agent against BBNinduced bladder carcinogenesis in mice when fed during the initiation phase. ' 2005 Wiley-Liss, Inc.Key words: chemoprevention; DITC; BBN; cyclin D1; BrdU labeling index; urinary bladder carcinogenesis Epidemiologic studies suggest that the consumption of green and yellow vegetables has an inverse relationship with cancer risk. [1][2][3][4][5][6][7] Organosulfur compounds that are present abundantly in a group of cruciferous vegetables or allium species have been shown to possess cancer chemopreventive properties. [8][9][10] Especially, isothiocyanates (ITC) are versatile chemopreventive agents in many animal systems.Cancer prevention studies of our group have demonstrated that benzyl isothiocyanate (BITC) inhibit methylazoxymethanol (MAM)-acetate induced intestinal carcinogenesis and diethylnitrosamine (DEN) induced hepatocarcinogenesis in rats, and sinigrin reduced 4-nitroquinoline 1-oxide-induced rat tongue carcinogenesis and DEN-induced hepatocarcinogenesis.11-14 We also found that BITC reduced not only unscheduled DNA synthesis (UDS) but also replicative DNA synthesis (RDS), induced by some genotoxic carcinogens, e.g., 2-acetylaminofluorene (AAF), MAM acetate, 9,10-dimethyl-1,2-benzanthracene (DMBA), and DEN....

BACKGROUND: Deep venous thrombosis (DVT) is a prevalent complication of orthopedic surgery. According in many studies. The incidence of DVT may be up to 50% if thromboprophylaxis is not available. AIM: The objective of this study was to check the degree of disease, clinical characteristics and analyzed factors in vulnerabilities with lower-limp DVT after orthopedic surgery in a Vietnam teaching hospital. METHODS: Orthopedic patients who met criteria were recruited at our hospital between August 2017 and June 2018. Ultrasound was used to discovering lower-limp DVT in pre-surgery and 7 days after surgery in all patients. RESULTS: The incidence of DVT after orthopedic surgery was 7.2%. Patients with older age (> 60) have a risk of 2 times higher of DVT after surgery than normal people (p < 0.05). The incidence of postoperative DVT was higher in immobile individuals > 72 hours (p < 0.05). Patients with prolonged surgical time (>120 minutes) had a higher risk of postoperative DVT than non-surgical patients’ surgery (p < 0.05). CONCLUSIONS: DVT remains a common complication following orthopedic surgery. Older age, immobility status, and surgical time have been found to be risky factors for the development of postoperative lower-limp DVT in orthopedic patients.

No abstract