scholarly journals Tobacco experimental model to induce urinary bladder neoplasms

2014 ◽  
Vol 41 (1) ◽  
pp. 056-060 ◽  
Author(s):  
José Alexandre Colli Neto ◽  
José Hélio Zen Júnior ◽  
André Del Negro ◽  
Nelson Adami Andreollo ◽  
Marina Rachel Araujo ◽  
...  
Keyword(s):  
Experimental Model ◽  
Bladder Wall ◽  
Bladder Neoplasms ◽  
Urinary Bladder Neoplasms ◽  
Experimental Models ◽  
Histopathological Study ◽  
High Concentrations ◽  
Carbon Dioxide Co2 ◽  
Harmful Effects ◽  
Chronic Use

OBJECTIVE: to develop an experimental model of exposure to tobacco burning (cigarette) products to assess the effects of its chronic use in relation to cancers of the bladder. METHODS: the animals were chronically exposed to the burning tobacco products in a semi-open chamber to simulate smoking. Thirty young Wistar rats were divided into two groups: one with 20 animals simulating smoking for six months, and ten not exposed control animals for the same period. After exposure by inhalation of cigarette smoke, animals were euthanized and subjected to histopathological study of the bladder wall. RESULTS: no tumor was found but mild and non significant alterations. The studies of hemo-oximetry (carboxyhemoglobin and methemoglobin) and the concentration of carbon dioxide (CO2) confirm that the animals were exposed to high concentrations of tobacco smoke and its derivatives. CONCLUSION: no bladder mucosal neoplasia was found in the pathological study of animals. The developed experimental models were highly efficient, practical and easy to use and can be used in other similar studies to determine the harmful effects caused by smoking.

scholarly journals A histopathological study of urinary bladder neoplasms

2021 ◽  
Vol 8 (1) ◽  
pp. 59-63
Author(s):  
Seva V Makwana ◽  
Preeti N Jhaveri ◽  
Kishan K Oza ◽  
Cherry K Shah
Keyword(s):  
Urinary Bladder ◽  
Bladder Neoplasms ◽  
Urinary Bladder Neoplasms ◽  
Histopathological Study

A Population-based Study of 538 Patients with Newly Detected Urinary Bladder Neoplasms Followed during 5 Years

2003 ◽  
Vol 37 (3) ◽  
pp. 195-201 ◽  
Author(s):  
Per Larsson ◽  
Hans Wijkström ◽  
Andreas Thorstenson ◽  
Jan Adolfsson ◽  
Ulf Norming ◽  
...  
Keyword(s):  
Urinary Bladder ◽  
Bladder Neoplasms ◽  
Urinary Bladder Neoplasms ◽  
Population Based ◽  
Population Based Study

Urinary bladder neoplasms: evaluation with contrast-enhanced MR imaging.

Radiology ◽  
1989 ◽  
Vol 172 (3) ◽  
pp. 739-743 ◽  
Author(s):  
J M Neuerburg ◽  
K Bohndorf ◽  
M Sohn ◽  
F Teufl ◽  
R W Guenther ◽  
...  
Keyword(s):  
Urinary Bladder ◽  
Mr Imaging ◽  
Bladder Neoplasms ◽  
Urinary Bladder Neoplasms ◽  
Contrast Enhanced

scholarly journals Evaluation of the heme oxygenase-1 expression in esophagitis and esophageal cancer induced by different reflux experimental models and diethylnitrosamine

2010 ◽  
Vol 25 (3) ◽  
pp. 304-310 ◽  
Author(s):  
Cleber Rosito Pinto Kruel ◽  
Luis Felipe Ribeiro Pinto ◽  
Tania Cristina Moita Blanco ◽  
Theresa Christina Barja-Fidalgo ◽  
Levi Lourenzo Melo ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Experimental Model ◽  
Heme Oxygenase ◽  
Inflammatory Cells ◽  
Acid Reflux ◽  
Experimental Models ◽  
Control Group ◽  
Heme Oxygenase 1 ◽  
Duodenal Reflux ◽  
Esophageal Carcinogenesis

PURPOSE: To study the expression of heme-oxygenase-1 (HO-1), an enzyme induced by oxidative stress, in specimens obtained from an experimental model in rats that evaluated the role of gastric and duodenal reflux in esophageal carcinogenesis. METHODS: Esophageal specimens embedded in paraffin obtained from different experimental groups of rats were used for immunohistochemistry analysis of HO-1 expression. The rats had been divided into the following groups and were killed after 22 weeks: (1) cardioplasty to induce acid reflux; (2) esophagoduodenal anastomosis to induce duodenal reflux; (3) no treatment; (4) cardioplasty + diethylnitrosamine (DEN); (5) esophagoduodenal anastomosis + DEN; and (6) DEN. The study sample comprised 3 specimens from each group with the most severe histopathological lesions found on each study branch. RESULTS: The expression of HO-1 was seen only in rat specimens submitted to esophagoduodenal anastomosis (Groups 2 and 5), and the analysis of mean fluorescence intensity revealed a significant increase of HO-1 expression (4.8 and 4.6 fold, respectively) when compared with the control group (Group 3) (p<0.05). The main target for HO-1 induction was the inflammatory cells inside the tumor or in subepithelial areas. Rats exposed to gastric reflux had no HO-1 expression. CONCLUSION: Reflux esophagitis induced by reflux of duodenal contents, which provoked considerable oxidative stress, may play an important role in esophageal carcinogenesis. Acid reflux did not induce oxidative stress in this experimental model.

Model Simplification for Offshore Platforms Using Model Refinement Scheme

2013 ◽  
Vol 284-287 ◽  
pp. 1436-1440 ◽  
Author(s):  
Min Zhang ◽  
Shu Qing Wang ◽  
Jia Li Fu ◽  
Xiao Long Xu
Keyword(s):  
Experimental Model ◽  
Degrees Of Freedom ◽  
Oil And Gas ◽  
Model Updating ◽  
Experimental Models ◽  
Offshore Platforms ◽  
Model Refinement ◽  
Jacket Platform ◽  
Cross Model ◽  
Offshore Oil And Gas

Offshore jacket platforms have been widely used in offshore oil and gas exploitation under hostile ocean environments. Finite element models of such structures need to have many degrees of freedom (DOFs) to represent the geometrical detail of complex structures, which leads to more computing power when performing the analysis and what’s more, the incompatibility in the number of degrees of freedom to the experimental models. Therefore, there is a need to simplify the analytical model by reducing the DOFs and in the process, making the essential eigen-properties agree with those of the experimental model is desired. In this paper, a scaled physical experimental model of an offshore jacket platform is simplified using the recently developed model refinement scheme. Mathematically, the procedure to implement the model refinement technique is an application of cross-model cross-mode (CMCM) method for model updating. The master degrees of freedom are chosen according to the placement of accelerometers in the experiment. Upon the completion of the refinement, the improved reduced jacket platform model matches the dynamic characteristics of the experimental model quite well.

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