Biomedical Research What is Biomedical Research n Biomedical

Biomedical Research

What is Biomedical Research n Biomedical research is the area of science devoted to the study of the processes of life; prevention and treatment of disease; and the genetic, lifestyle and environmental factors related to disease and health.

Scientific Method Science is a “continuous stream of ideas that are constantly being reshaped. ” It is discovery-based and/or inquiry based. n Involves critical thinking, encourages creativity and seeking solutions to problems n

Observation n Hypothesis n Experiment n Conclusion n Science is a way of making predictions and making decisions for the future n

Basic Biomedical Research Conducted to increase fundamental knowledge and understanding of life processes and diseases n It is NOT directed toward solving any particular problem n Provides the building blocks for other types of research n

Applied Research Directed toward specific objectives such as developing new medications n Involves the application of existing knowledge to a problem n Can be conducted with animals, computer models and tissue cultures n

Clinical Research Takes place after the other 2 n Clinical research tests a particular medication or treatments in humans n Takes place in a hospital or other health care facility n May lead to the need for further research n

Biomedical Research Methods n Researchers use a combination of highly interdependent, state of the art methods to understand life processes.

Chemical, mathematical and computer simulations Used to simulate living organisms n Helpful in understanding complicated biological processes n Helpful in the preliminary stages of research n Provide ideas about new research directions n

Strengths Models increase the speed and efficiency with which data can be studied and processed. n If the model is simple, it can be very accurate n Reduces the number of animals needed for research n

Limitations They cannot replace laboratory testing n The reliability is a function of how well the organism being researched is defined n Expensive n Cannot replace living systems n

In vitro tests Experiments performed in laboratory containers using tissues or cells. n Literally means “in glass” n Scientists use cell cultures, isolated tissues, in the early and intermediate phases of research n

Strengths Allow scientist to study a single effect in isolation without interference n Less expensive, less time consuming and more accurate n Able to control more readily n Critical to the study of viruses n

Limitations Toxic effects are complex therefore it cannot be duplicated n Cells grown in culture are not exposed to other living organism processes n Cells do not metabolize toxins in culture the same n Difficult to maintain differentiated cells n

Nonhuman Animal Models Animals provide the best surrogate for humans n Results from animal studies can be applied to humans n Animals provide a complex living system n

Strengths Ethical alternative to using humans n Whole integrated biological system n Animals share the same structures and function as humans n

Limitations Animals are not identical to humans n Research animals are expensive n Animal research is regulated by extensive federal regulations n

Human Clinical Trials Important component n 3 major phases of clinical trials n ¨ Phase III

Strengths Actual human data on the efficacy and safety of new medications n Ethical and moral limitations n Limitations n Requires extensive pre-clinical testing n Numerous variables affect test data

Epidemiological Studies Epidemiology is the study of disease incidence and its distribution in a population n To prevent disease, need to know what causes it n Three general types of epidemiological studies n

Experimental Epidemiology Human equivalent to animal testing such as providing or withholding a substance to determine toxic or beneficial effects. n Greatly limited by ethical and legal considerations and by securing large numbers of people n

Descriptive Epidemiology Analyzing data on the extent and distribution of disease n Looking for correlations of disease with diet, air quality and occupation n Often comparisons are made between countries and smaller geographic regions. n

Observational Epidemiology Uses data from individuals or small groups n Data is evaluated statistically to determine relationship between variables and disease n Cohort studies are done over time on a homogeneous group n Case-controlled studies uses control group n

Strengths Epidemiological studies offer direct opportunity to study diseases n Identify patterns and distribution of disease Limitations n Considerable human exposure can take place before a toxic effect is detected n Difficult to demonstrate a cause and effect relationship because information is gathered ‘after the fact’ n Difficulty in determining the control group n

Epidemiological Studies: 1775 Sir Percival Pott of England reported chimney sweeps had high incidence of scrotal cancer n Early 1900’s established 14 th century black plague was spread from rats to fleas to us n 1854 Dr John Snow – cholera from contaminated water pump n

Epidemiological Studies: Linked occupational settings: asbestos plants and coal mines to various lung diseases n Hammond-Horn Smoking Study: effect on cigarette smoking on death rates from cancer and other diseases n