Radiation Biology and Pathology 2 PDF

**RADIATION BIOLOGY** **ATOM** - An atom is the fundamental building block of matter. It is the smallest unit of an element that retains the chemical properties of that element. Atoms are composed of three main subatomic particles: protons, neutrons, and electrons. ***Atoms*** are electrically neu...

**RADIATION BIOLOGY** **ATOM** - An atom is the fundamental building block of matter. It is the smallest unit of an element that retains the chemical properties of that element. Atoms are composed of three main subatomic particles: protons, neutrons, and electrons. ***Atoms*** are electrically neutral because they have an equal number of protons and electrons, resulting in overall zero net charge. The mass of an atom is primarily determined by the [combined masses of its protons and neutrons, while its size is determined by the distribution of its electrons.] **PARTS OF THE ATOMS** **Protons** - - - **Neutrons** - - - - - **Electrons** - - - - - - **MOLECULES** - - - - - **IONIC BONDS** - - **METALLIC BONDS** - **HYDROGEN BOND** - - **BASIC CELLULAR BIOLOGY** - - - - - - **CELLULAR STRUCTURE** - - **Nucleus:** The nucleus [houses the cell\'s genetic material], including DNA, in the form of chromosomes. - **Cytoplasm:** The cytoplasm is the [gel-like substance] that fills the space between the cell membrane and the nucleus. - **Endoplasmic Reticulum (ER):** The ER is a network of membranes [involved in protein synthesis, folding, and transport.] - **Golgi Apparatus (Golgi Complex):** The Golgi apparatus [modifies, sorts, and packages proteins and lipids for transport] within the cell or secretion to the extracellular environment. - **Mitochondria:** Mitochondria are often referred to as the \"powerhouses\" of the cell because they [produce energy through cellular respiration. ] - **Lysosomes:** Lysosomes contain enzymes that [break down waste materials, cellular debris, and foreign substances through processes] called ***autophagy*** and ***phagocytosis***. - **Peroxisomes:** Peroxisomes contain enzymes that [break down fatty acids and detoxify harmful substances, producing ***hydrogen peroxide*** as a byproduct. ] - **Cytoskeleton:** The cytoskeleton is a network of protein filaments (microtubules, microfilaments, and intermediate filaments) that [provide structural support, maintain cell shape, and facilitate cellular movement and transport.] ***Centrioles*** are cylindrical structures [involved in cell division and the organization of microtubules.] ***Centrosomes*** are regions near the nucleus that [contain centrioles and help coordinate cell division.] - - - **BASIC CELL CHEMISTRY** 1. 2. **METABOLISM** - - - **ORGANIC AND INORGANIC COMPOUND** - - **Enzymes and Catalysts** - - - - - - - - - **INTERPHASE** - - - - **MITOSIS** - - - - - **CYTOKINESIS** - **RAD PATHO 2** **GUIDE FOR SMALL GROUP DISCUSSION** **Pathology -** The [study of diseases] that can cause abnormalities in the structure or function of various organ systems. **Disease -** Pattern of the body's response to some form of injury that causes variation of normal conditions - *Pathologic process can be defined as following:* - - - - - - **Terminologies** **Etiology -** study of the cause of a disease: - - - - - - **Prevalence -** number of cases found in a given population **Incidence** - number of cases found in a given period. **Iatrogenic --** diseases caused by physicians or their treatment **Nosocomial --** infections at the acute care facility **Community acquired --** infections that develop outside the healthcare facility **Idiopathic --** underlying cause is unknown **Acute -** quick onset and last for a short period e.g. Pneumonia May be followed by lasting effects -- **sequelae** e.g. Stroke, or cerebrovascular accident, resulting in long-term neurologic deficits **Chronic -** diseases may manifest more slowly and last for a very long time e.g. Multiple sclerosis, diabetes mellitus experiencing hypoglycemia or hyperglycemia **Diagnosis -** is the identification of a disease an individual is believed to have **Prognosis -** predicted course and outcome of the disease **Morphology -** The structure of cells or tissue **Epidemiology -** is the investigation of disease in large groups **Manifestations of Pathologic Processes** **INFLAMMATION** - **Process of inflammatory reaction:** **Dilation** of arterioles, capillaries, and venules (hyperemia) **Heat and redness** Venules and capillaries become abnormally permeable (allowing exudate in the surrounding tissue) **Swelling** produces pressure on sensitive nerve endings (Pain) **Fever --** common in inflammatory conditions **Clinical signs of acute inflammation** - - - - - **Events that occur in Inflammatory response** 1. 2. 3. 4. **EDEMA** - **Localized -** inflammatory reaction **Anasarca --** [Generalized edema] occurs with pronounced swelling of subcutaneous tissues throughout the body - - **ISCHEMIA** - *May be caused by:* - - - - **INFARCT** [Localized area of ischemic necrosis within a tissue or organ] produced by occlusion of either its arterial supply or its venous drainage. **Necrosis --** [tissue death] that may be caused by lack of blood supply **Gangrene --** condition that [results from death of tissue] due to lack of blood supply **HEMORRHAGE** - - **Hematoma --** trapped blood within the body tissues **Petechiae --** [minimal hemorrhages into the skin], mucous membranes, or serosal surfaces **Purpura -** Slightly larger hemorrhages **Ecchymosis --** [large (greater than 1 to 2 cm) subcutaneous hematoma] (a hematoma that appears just under the skin). Bruises **ALTERATIONS OF CELL GROWTH** Notes: **-Plasia -** formation, growth, proliferation (number) **-trophy -** nutrition, nourishment, growth (size) **Atrophy --** reduction in the size or number of cells in an organ or tissue **Hypoplasia** - underdevelopment or incomplete development of organs **Aplasia --** failure to develop or an organ is largely or wholly absent **Hypertrophy --** increase in the size of cells in an organ or tissue **Hyperplasia --** increased number of cells **Metaplasia -** conversion of one cell type into another cell type that is not normal for that tissue **Dysplasia --** loss of uniformity of individual cells and their architectural orientation. Turns abnormal. **NEOPLASIA** - - - - - - - **Basic components of tumors** 1. - 2. - **Benign tumors** - - - e.g. pituitary, islets of Langerhans, brain, spinal cord, trachea, esophagus. - **Malignant tumors (Cancers)** - - - - - - - **Sarcoma** - - **Carcinogens** - **Chemical carcinogens** - - The spread of malignant cancer cells resulting in a secondary tumor distant from the primary lesion is termed **metastasis** Malignant neoplasms disseminate to distant sites by one of three ways 1. 2. 3. **Seeding (diffuse spread)** - - - **Lymphatic spread** - - - **Hematogenous spread** - - - - - **Staging of Malignant Tumor** - - - - - - - **TNM system:** - - - - - - **In situ---**Abnormal cells are present but have not spread to nearby tissue. **Localized---**Cancer is limited to the place where it started, with no sign that it has spread. **Regional---**Cancer has spread to nearby lymph nodes, tissues, or organs. **Distant---**Cancer has spread to distant parts of the body. **Unknown---**There is not enough information to figure out the stage. **Grading of Malignant Tumor** - - - - **Grade 1 --** The cancer cells look very similar to normal cells and are growing slowly (Well differentiated) (low grade) **Grade 2 --** The cells look unlike normal cells and are growing more quickly than normal. Moderately differentiated (intermediate grade) **Grade 3 --** The cancer cells look very abnormal and are growing quickly Poorly differentiated (high grade) **Grade 4 -** Tumors tend to grow rapidly and spread faster (Undifferentiated) (high grade) **GX -** means that the grade can\'t be assessed. It is also called **undetermined grade.** **Hereditary Diseases** - - - - - - - - - **Autosomal Dominant disorders** - - **Autosomal Recessive disorders** - - - - **Acquired Immunodeficiency Syndrome** - - - - - - - - **SKELETAL SYSTEM** - - - - - - - **Major types of bones** ***Compact bone*** - - - - ***Cancellous (spongy) bone*** - - - **Osteocytes** ***Osteoclasts*** - - ***Osteoblasts*** - - - - **Greulich and Pyle method** - - **CONGENITAL AND HEREDITARY DISEASES** ***Osteogenesis Imperfecta*** - - - 1. - - 2. - ***Achondroplasia*** - - - - - ***Osteopetrosis*** - - - - **Hand and Foot Malformations** - - - - **VERTEBRAL ANOMALIES** ***Scoliosis*** - - - - ***Significance of Cobb's angle:*** - - - - ***Transitional Vertebra*** - - - - ***Cervical Rib*** - - - ***Spina bifida*** - - - ***Spina bifida occulta*** - - - ***Spina bifida cystica*** - - - - - - - - - **VERTEBRAL COLUMN DISEASE** ***Spondylolisthesis*** - - - - - - - **Spondylolysis** - - **Spondylosis** - - **CRANIAL ANOMALIES** ***Craniosynostosis*** - - - - *Types:* 1. 2. 3. 4. ***Sagittal synostosis (Scaphocephaly)*** - - - ***Coronal synostosis*** - - - - - **Unicoronal synostosis (Anterior Plagiocephaly)** - - - - - **Bicoronal synostosis (Brachycephaly)** - - - **Metopic synostosis (Trigonocephaly)** - - - - - **Lambdoid synostosis (posterior Plagiocephaly)** - - - - **Anencephaly** - - - **INFLAMMATORY DISEASES** ***Osteomyelitis*** - - - - - - - - - - - - **Tuberculosis** - - - **ARTHROPATHIES** - *limited to:* 1. 2. 3. 4. - ***Infectious Arthritis*** - - ***Rheumatoid Arthritis*** - - - - - - ***Psoriatic Arthritis*** - - ***Reiter Syndrome*** - - - ***Juvenile Rheumatoid Arthritis*** - - - ***Ankylosing Spondylitis*** - - - ***Osteoarthritis*** - - - - - - - - - - **Associated Joint Structures** - - - - **METABOLIC BONE DISEASE** ***Osteoporosis*** - - - - - - - - - *Radiographic Appearance* - - ***Osteomalacia*** - - - *Radiographic Appearance* - ***Rickets*** - *Radiographic Appearance* - **Gout** - - *Radiographic appearance* - - ***Paget's Disease (osteitis deformans)*** - - - *Radiographic appearance* - - **NEOPLASTIC DISEASES** ***Bone Tumors*** - - - - - - - - - ***Osteochondroma (Exostosis)*** - - - - ***Osteoma*** - - ***Enchondroma*** - - - ***Giant cell tumor (Osteoclastoma)*** - - - - - ***Osteosarcoma (osteogenic sarcoma)*** - - - - ***Ewing sarcoma*** - - - ***Chondrosarcoma*** - - - **FRACTURES** - - - - - - - - - - - - - - - - - **Common Fractures and Dislocations** - - - - - - - - - -