Natural and Artificial Defenses: Immunology and Medicine
Natural Defenses
Natural defenses are any defenses formed that act against a pathogen or illness.
- Genetic Resistance: Some individuals are immune to certain pathogens.
- Anatomic Barriers: These prevent the passage of pathogens within the organism.
- Inflammatory Response: Characterized by swelling, pain, etc. Phagocytes destroy the pathogen.
- Inducible Defenses: Specific defenses are triggered in response to the presence of an antigen. Lymphocytes, when presented with the foreign substance, respond by producing proteins that act against the antigen.
Artificial Defenses
Surgery
Surgery is to intervene manually and instrumentally in the affected organ of the patient.
Transplantation
Transplantation involves implanting an organ or tissue from a donor into a recipient. When the donor is the same patient, it is called autologous, and if it is from another individual, it is called allogeneic. Organ transplants are more complicated than tissue transplants. The main problem is rejection, as the body perceives the transplanted organ as foreign and the immune system tries to destroy it. Compatibility tests are required to help prevent rejection. Transplantation is sometimes the only means to prevent death or improve the quality of life.
Medicinal Substances
Medicinal substances are used in medicine to prevent illness, combat it, and alleviate its effects. They are produced by pharmaceutical industries.
- Vaccines: These have antigenic capacity and generate immunological memory against an antigen.
- Serum: Antibodies are injected into the patient. The serum is made by another body that has previously contacted the pathogen. It is administered when immediate action is necessary.
- Antibiotics: Used to destroy or prevent the metabolism of prokaryotes. The first antibiotic was penicillin, discovered by Fleming in 1929. Fleming, while studying mutations, found one of his cultures contaminated by a fungus. Around the contaminated area, there were no bacteria, which he attributed to the action of a substance produced by the fungus. Penicillin began to be commercialized in 1943, and in 1944, it was used to treat the wounded in the Battle of Normandy. The discovery of penicillin was a revolution in medical science.
Rational Use of Drugs
- Weigh the beneficial and harmful effects in each patient.
- Prescribe medications available in pharmacies.
- Choose the cheapest among the different possibilities.
- Inform the patient of administration patterns, especially dosage and duration of treatment.
Drug Patents
The manufacture of new pharmaceuticals involves medical industries that must make large investments over time, after many clinical trials. To compensate for these investments, each new product sold is protected by patent law, which allows exclusive operation for 20 years by the laboratories. This prevents innovations in developing countries, which cannot manufacture or import generic drugs at a much lower price.
Constraints on Medical Research
The scientific method is developed through various types of studies:
- Observation: The researcher observes the situation without controlling any type of variable.
- Experimentation: The researcher controls and manipulates the variables to determine adverse effects, etc.
Drug research is done in successive stages. Preclinical research is conducted in laboratory cell cultures and animals. Later, clinical trials study the drug’s behavior in humans.
Preformationism and Epigenesis
The observation of spermatozoa with a rudimentary microscope led to the belief that it was a minuscule man that, after fertilization, would grow and lead to an individual. This hypothesis was called preformationism. When microscopy techniques improved, epigenesis was postulated, according to which after fertilization, there is not only growth but a series of structural transformations. Later, Darwin returned to classical pangenesis, which states that every organ of the body of both parents would produce some rudiments or small gemmules that would travel through the blood to the genitals and from there pass to the children. Darwin called this the provisional hypothesis of pangenesis.