1.Vanishing Pancreatic Grafts.
Christopher PIVETTI ; In Chul HONG ; Chang H YOO ; Sun LEE ; Kenny KIM ; Gregory EMMANUEL ; Jason KIM ; Romy CHUNG ; Slawomir NIEWIADOMSKI ; Paul WOLF ; R F GITTES
Yonsei Medical Journal 2004;45(6):1169-1172
Comparison of pancreaticoduodenal transplants (PDT) and duct-ligated pancreas transplant (DLPT) were performed using syngeneic and allogeneic studies in rats. Both DLPT and PDT allogeneic grafts showed mild rejection. DLPT groups showed disorganized pathology and acini replaced by fat. Eventually, massive fibrosis was seen in the Islets of Langerhans, as well as rejection cellular infiltrates. In both PDT groups, normal histology was observed in the same period. Thus the effect of duct occlusion is highly detrimental for the grafts.
Animals
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Graft Rejection/pathology
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Ligation/adverse effects
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Pancreas/*pathology
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Pancreas Transplantation/*adverse effects
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Pancreatic Ducts/surgery
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Postoperative Period
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Rats
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Rats, Inbred Lew
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Rats, Sprague-Dawley
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Research Support, Non-U.S. Gov't
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Transplantation, Homologous
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Transplantation, Isogeneic
2.Gonadal Tumors Developed from Consecutively Transplanted Spleens Bearing Gonad Implants.
In Chul HONG ; Sun LEE ; Chang Hyun YOO ; Kenny K KIM ; Jason KIM ; Gregory EMMANUEL ; Slawomir NIEWIADOMSKI ; Paul WOLF ; Ruben F GITTES
Yonsei Medical Journal 2004;45(6):1136-1142
This study was conducted by consecutively transplanting spleens, which had gonads implanted previously. A total of 84 cases for infantile testicles and 106 cases for ovarian follicles were performed. In the case of ovarian implants, the results were determined by the total number of follicle implants. A modified spleen transplantation technique called double implantation of ovarian follicles was applied to increase the amount of the implants. In this technique, an extra spleen is implanted into the potential donor so that the ovarian follicles can be implanted to two different spleens, doubling the amount of implants. Through consecutive spleen transplantation, we observed the results beyond a typical rat's life span. In many of these cases, we found more aggressive forms of malignant tumor, seminoma and dysgerminoma. We present the results and discuss possible pathogenic mechanisms of tumor formation.
Animals
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Animals, Newborn
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Female
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Male
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Ovarian Neoplasms/*etiology
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Ovary/*transplantation
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Rats
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Rats, Inbred Lew
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Research Support, Non-U.S. Gov't
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Spleen/*surgery/*transplantation
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Testicular Neoplasms/*etiology/pathology
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Testis/*transplantation
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*Transplantation, Heterotopic
3.Effects of Basella alba and Hibiscus macranthus extracts on testosterone production of adult rat and bull Leydig cells.
Paul F MOUNDIPA ; Nathalie Sara E BEBOY ; Fabien ZELEFACK ; Silvére NGOUELA ; Etienne TSAMO ; Wolf-Bernhard SCHILL ; Thomas K MONSEES
Asian Journal of Andrology 2005;7(4):411-417
AIMTo determine the androgenic effects of Basella alba and Hibiscus macranthus extracts in the rat and the bull, and to develop a novel in vitro test system using Leydig cells from bull testes.
METHODSThe effect of methanol extracts from both plants on testosterone production in isolated Leydig cells from the rat and the bull was analyzed using 125I-radioimmunoassay (125I-RIA). Rat Leydig cells were obtained by common methods, whereas a novel technique was used to purify Leydig cells from bull testes.
RESULTSBull testes from the slaughter house were a cheap source of pure Leydig cells. In culture, these cells produced testosterone for 5-6 days, which can be stimulated by human chorionic gonadotrophin (hCG). Basella alba extracts significantly enhanced testosterone production in bull and rat Leydig cells in a concentration-dependent manner. Hibiscus macranthus showed no androgenic effect but was shown to inhibit testosterone production at higher concentrations.
CONCLUSIONLeydig cells purified from bull testes can be used as an alternative tool in experimental animal research. Certain fractions of Basella alba extract demonstrated androgenic potential whereas Hibiscus macranthus extracts did not.
Animals ; Cattle ; Cells, Cultured ; Hibiscus ; Iodine Radioisotopes ; Leydig Cells ; cytology ; drug effects ; metabolism ; Male ; Methanol ; Plant Extracts ; pharmacology ; Plants, Edible ; Rats ; Rats, Sprague-Dawley ; Solvents ; Testosterone ; biosynthesis
4.Population based cohort study for Pediatric Infectious Diseases research in Vietnam
Lay-Myint Yoshida ; Motoi Suzuki ; Vu Dinh Thiem ; Wolf Peter Smith ; Ataru Tsuzuki ; Vu Thi Thu Huong ; Kensuke Takahashi ; Masami Miyakawa ; Nguyen Thi Hien Anh ; Kiwao Watanabe ; Nguyen Thu Thuy Ai ; Le Huu Tho ; Paul Kilgore ; Hiroshi Yoshino ; Michiko Toizumi ; Michio Yasunami ; Hiroyuki Moriuchi ; Dang Duc Anh ; Koya Ariyoshi
Tropical Medicine and Health 2014;():-
A population-based cohort study on pediatric infectious diseases was established at Khanh Hoa Province, central Vietnam in 2006, to determine the etiology and risk factors for severe pediatric infectious diseases (SPID) such as acute respiratory infection (ARI), diarrhea and dengue which are the major causes of under 5 mortality. A population census survey was conducted in Nha-Trang and Ninh-Hoa to collect demographic, social-behavioral data and disease burden on SPID. The study site covered a population of 353,525 residing in 75,826 households with 24,781 children less than 5 years. Hospital databases from two hospitals covering the region were obtained. Linking the census and hospital databases, we were able to investigate on a variety of SPID such as environmental tobacco smoking exposure and increased risked of pediatric pneumonia hospitalization, population density, water supply and risk of dengue fever and animal livestock and risk of hospitalized diarrhea. To determine incidence, viral etiology and risk factors for pediatric ARI/pneumonia, we setup a population based prospective hospitalized Pediatric ARI surveillance at Khanh Hoa General Hospital, Nha-Trang in February 2007. The study has revealed RSV, rhinovirus and influenza A as major viral pathogens, role of multiple viral infection and its interaction with bacteria in the development of pneumonia. In addition, we are also conducting a birth cohort study to investigate the incidence of congenital infection and its impact on physical-neurological development, and role of host genetic polymorphism on SPID hospitalization in Vietnam. Population mobility, high cost of regular census update and low mortality are the challenges.
5.Population Based Cohort Study for Pediatric Infectious Diseases Research in Vietnam
Lay-Myint Yoshida ; Motoi Suzuki ; Vu Dinh Thiem ; Wolf Peter Smith ; Ataru Tsuzuki ; Vu Thi Thu Huong ; Kensuke Takahashi ; Masami Miyakawa ; Nguyen Thi Hien Anh ; Kiwao Watanabe ; Nguyen Thu Thuy Ai ; Le Huu Tho ; Paul Kilgore ; Hiroshi Yoshino ; Michiko Toizumi ; Michio Yasunami ; Hiroyuki Moriuchi ; Dang Duc Anh ; Koya Ariyoshi
Tropical Medicine and Health 2014;42(2SUPPLEMENT):S47-S58
A population-based cohort study on pediatric infectious diseases was established at Khanh Hoa Province, central Vietnam in 2006, to determine the etiology and risk factors for severe pediatric infectious diseases (SPID) such as acute respiratory infection (ARI), diarrhea and dengue which are the major causes of under 5 mortality. A population census survey was conducted in Nha-Trang and Ninh-Hoa to collect demographic, social-behavioral data and disease burden on SPID. The study site covered a population of 353,525 residing in 75,826 households with 24,781 children less than 5 years. Hospital databases from two hospitals covering the region were obtained. Linking the census and hospital databases, we were able to investigate on a variety of SPID such as environmental tobacco smoking exposure and increased risked of pediatric pneumonia hospitalization, population density, water supply and risk of dengue fever and animal livestock and risk of hospitalized diarrhea. To determine incidence, viral etiology and risk factors for pediatric ARI/pneumonia, we setup a population based prospective hospitalized Pediatric ARI surveillance at Khanh Hoa General Hospital, Nha-Trang in February 2007. The study has revealed RSV, rhinovirus and influenza A as major viral pathogens, role of multiple viral infection and its interaction with bacteria in the development of pneumonia. In addition, we are also conducting a birth cohort study to investigate the incidence of congenital infection and its impact on physical-neurological development, and role of host genetic polymorphism on SPID hospitalization in Vietnam. Population mobility, high cost of regular census update and low mortality are the challenges.
6.Surface roughness of zirconia for full-contour crowns after clinically simulated grinding and polishing.
Rim HMAIDOUCH ; Wolf-Dieter MÜLLER ; Hans-Christoph LAUER ; Paul WEIGL
International Journal of Oral Science 2014;6(4):241-246
The aim of this study was to evaluate the effect of controlled intraoral grinding and polishing on the roughness of full-contour zirconia compared to classical veneered zirconia. Thirty bar-shaped zirconia specimens were fabricated and divided into two groups (n=15). Fifteen specimens (group 1) were glazed and 15 specimens (group 2) were veneered with feldspathic ceramic and then glazed. Prior to grinding, maximum roughness depth (Rmax) values were measured using a profilometer, 5 times per specimen. Simulated clinical grinding and polishing were performed on the specimens under water coolant for 15 s and 2 N pressure. For grinding, NTI diamonds burs with grain sizes of 20 µm, 10 µm, and 7.5 µm were used sequentially. The ground surfaces were polished using NTI kits with coarse, medium and fine polishers. After each step, Rmax values were determined. Differences between groups were examined using one-way analysis of variance (ANOVA). The roughness of group 1 was significantly lower than that of group 2. The roughness increased significantly after coarse grinding in both groups. The results after glazing were similar to those obtained after fine grinding for non-veneered zirconia. However, fine-ground veneered zirconia had significantly higher roughness than venerred, glazed zirconia. No significant difference was found between fine-polished and glazed zirconia, but after the fine polishing of veneered zirconia, the roughness was significantly higher than after glazing. It can be concluded that for full-contour zirconia, fewer defects and lower roughness values resulted after grinding and polishing compared to veneered zirconia. After polishing zirconia, lower roughness values were achieved compared to glazing; more interesting was that the grinding of glazed zirconia using the NTI three-step system could deliver smooth surfaces comparable to untreated glazed zirconia surfaces.
Aluminum Silicates
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chemistry
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Ceramics
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chemistry
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Crowns
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Dental Materials
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chemistry
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Dental Polishing
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instrumentation
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methods
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Dental Prosthesis Design
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Dental Veneers
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Diamond
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chemistry
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Humans
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Materials Testing
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Microscopy, Electron, Scanning
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Particle Size
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Potassium Compounds
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chemistry
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Pressure
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Surface Properties
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Time Factors
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Water
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chemistry
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Yttrium
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chemistry
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Zirconium
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chemistry