Experimental model of pulmonary emphysema by exposure of cigarette smoke.

A Doença Pulmonar Obstrutiva Crônica (DPOC) destaca-se como um grave problema de saúde no mundo. O enfisema pulmonar, dentro do espectro das DPOC, caracteriza-se pelo alargamento dos espaços aéreos distais resultante da destruição do parênquima pulmonar. O tabagismo é considerado o principal fator relacionado ao surgimento da patologia. Considerando a escassez de aparelhos comercializados para exposição à fumaça de cigarro, bem como o elevado custo dos existentes, o presente projeto propôs um modelo experimental de enfisema por exposição à fumaça utilizando um novo aparato. Foram realizadas avaliações morfométricas e funcionais nos pulmões de ratos expostos à fumaça ou ao ar ambiente. Além disso, o peso dos animais foi aferido semanalmente. Os resultados indicaram alargamento dos espaços aéreos pulmonares, além de redução do ganho de peso nos animais expostos. Não houve diferenças funcionais entre os grupos controle e experimental. O trabalho objetivou o desenvolvimento de um aparato eficiente e menos custoso para estudos relacionados ao enfisema pulmonar.The Chronic Obstructive Pulmonary Disease (COPD) stands out as a serious health problem in the world. The pulmonary emphysema, in the spectrum of COPD, has as main feature the enlargement of the airspaces distal resulting from destruction of lung parenchyma. Smoking is considered the main factor related to the development of pathology. Considering the lack of machines marketed for exposure to cigarette smoke, as well as the high cost of devices available, the currently project has proposed a experimental model of pulmonary emphysema induced by the use of a new apparatus. Were performed morphometric and functional measurements in the lung of rats exposed to cigarette smoke or clean air. Further, the animal weight was measured weekly. The results indicated enlargement of the pulmonary airspaces, as well as reduction of weight gain in animals exposed. There were no functional differences between control and experimental groups. The current study aimed to the development of an efficient and less costly apparatus for experimental studies related to the pulmonary emphysema

Animal models in chronic obstructive pulmonary disease-an overview

Chronic obstructive pulmonary disease (COPD) is characterized by progressive airway obstruction resultant from an augmented inflammatory response of the respiratory tract to noxious particles and gases. Previous reports present a number of different hypotheses about the etiology and pathophysiology of COPD. The generating mechanisms of the disease are subject of much speculation, and a series of questions and controversies among experts still remain. In this context, several experimental models have been proposed in order to broaden the knowledge on the pathophysiological characteristics of the disease, as well as the search for new therapeutic approaches for acute or chronically injured lung tissue. This review aims to present the main experimental models of COPD, more specifically emphysema, as well as to describe the main characteristics, advantages, disadvantages, possibilities of application, and potential contribution of each of these models for the knowledge on the pathophysiological aspects and to test new treatment options for obstructive lung diseases

Cell Therapy with Bone Marrow Mononuclear Cells in Elastase-Induced Pulmonary Emphysema

Emphysema is characterized by destruction of alveolar walls with loss of gas exchange surface and consequent progressive dyspnea. This study aimed to evaluate the efficiency of cell therapy with bone marrow mononuclear cells (BMMC) in an animal model of elastase-induced pulmonary emphysema. Emphysema was induced in C57Bl/J6 female mice by intranasal instillation of elastase. After 21 days, the mice received bone marrow mononuclear cells from EGFP male mice with C57Bl/J6 background. The groups were assessed by comparison and statistically significant differences (p & 0. 05) were observed among the groups treated with BMMC and evaluated after 7, 14 and 21 days. Analysis of the mean linear intercept (Lm) values for the different groups allowed to observe that the group treated with BMMC and evaluated after 21 days showed the most significant result. The group that received no treatment showed a statistically significant difference when compared to other groups, except the group treated and evaluated after 21 days, evidencing the efficacy of cell therapy with BMMC in pulmonary emphysema. © 2012 Springer Science+Business Media New York

Exploring middle school students' use of inscriptions in project-based science classrooms This paper was edited by former Section Coeditors Gregory J. Kelly and Richard E. Mayer

This study explores seventh graders' use of inscriptions in a teacher-designed project-based science unit. To investigate students' learning practices during the 8-month water quality unit, we collected multiple sources of data (e.g., classroom video recordings, student artifacts, and teacher interviews) and employed analytical methods that drew from a naturalistic approach. The findings showed that throughout the unit, provided with the teachers' scaffold and social, conceptual, and material resources, the seventh graders were able to use various inscriptions (e.g., digital pictures, Web pages, and models) to demonstrate meaningful inscriptional practices such as creating and using inscriptions to make arguments, to represent conceptual understandings, and to engage in thoughtful discussions. Inscriptions and associated practices provided students with experiences and understandings about certain ways to organize, transform, and link data or scientific ideas. However, when constructing inscriptions, students did not consider how the inscriptions could serve certain reasoning purposes. In addition, more scaffolds were needed to help students use multiple inscriptions to make a coherent argument. © 2006 Wiley Periodicals, Inc. Sci Ed 90 :852–873, 2006Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55781/1/20154_ftp.pd

A new experimental model of cigarette smoke-induced emphysema in Wistar rats

Objective: To describe a new murine model of cigarette smoke-induced emphysema. Methods: Twenty-four male Wistar rats were divided into two groups: the cigarette smoke group, comprising 12 rats exposed to smoke from 12 commercial filter cigarettes three times a day (a total of 36 cigarettes per day) every day for 30 weeks; and the control group, comprising 12 rats exposed to room air three times a day every day for 30 weeks. Lung function was assessed by mechanical ventilation, and emphysema was morphometrically assessed by measurement of the mean linear intercept (Lm). Results: The mean weight gain was significantly (approximately ten times) lower in the cigarette smoke group than in the control group. The Lm was 25.0% higher in the cigarette smoke group. There was a trend toward worsening of lung function parameters in the cigarette smoke group. Conclusions: The new murine model of cigarette smoke-induced emphysema and the methodology employed in the present study are effective and reproducible, representing a promising and economically viable option for use in studies investigating the pathophysiology of and therapeutic approaches to COPD