Haseeb Ullah

Platyhelminthes Definition Platyhelminthes (Flatworms)   Characteristics: Flattened, bilaterally symmetrical bodies.   Group: Includes both freeliving and parasitic species.   Medical Importance: Parasitic flatworms include classes like Trematoda (flukes) and Cestoda (tapeworms). Lifecycle in Humans Trematodes (Flukes) 1 . Eggs: Released in human feces or urine. 2. Larval Stages: Eggs hatch into miracidia, infecting intermediate hosts (usually snails). 3. Cercariae: Develop within snails, released into water. 4. Human Infection: Penetrate human skin or ingested. 5. Adult Stage : Migrate to organs (e.g., liver, lungs), mature into adult flukes. 6. Reproduction: Adults lay eggs, excreted from human body. Example: Schistosoma spp. Lifecycle 1. Eggs: Excreted in feces. 2. Miracidia: Hatch and infect snails. 3. Cercariae: Released from snails, penetrate human skin. 4. Schistosomula: Migrate through the bloodstream to the liver. 5. Adults:

  Nematodes (Helminths): Lifecycle in Humans, Diagnosis, and Treatment   Definition Nematodes (Roundworms)   Phylum: Nematoda   Characteristics:    Cylindrical, elongated, unsegmented bodies   Habitats:    Soil, Water, Parasitic environments (plants and animals, including humans) Lifecycle in Humans 1. Ingestion/Penetration: Ingest eggs/larvae via food, water, soil; some penetrate skin. 2. Larval Migration: Larvae move through tissues (e.g., lungs, intestines). 3. Adult Stage: Mature in specific body locations (e.g., intestines, lymphatics). 4. Reproduction : Adults reproduce; eggs excreted in feces or remain in tissues. 5. Environmental Stage : Eggs/larvae develop in environment; become infectious. Ascaris lumbricoides Example 1. Ingestion: Ingest eggs via contaminated food/water. 2. Hatching: Eggs hatch in intestines. 3. Migration: Larvae move to lungs, then throat, swallowed back to intestines. 4. Maturation: Mature into adults in intest

Toxoplasma: Its Life Cycle, Symptoms, and Prevention Life cycle   Definitive Host: Domestic cats and other felines.   Intermediate Hosts : Humans and other mammals. Cycle in Cats: 1. Cats ingest cysts (e.g., from raw meat like mice). 2. Cysts release bradyzoites in the small intestine. 3. Bradyzoites infect mucosal cells and differentiate into gametocytes. 4. Gametocytes fuse to form oocysts. 5. Oocysts are excreted in cat feces. Human Infection: 1. Ingestion of cysts via:     Undercooked meat     Accidental contact with cat feces 2. Cysts rupture in the small intestine, releasing forms that invade the gut wall. 3. Forms differentiate into tachyzoites (rapidly multiplying trophozoites). 4. Tachyzoites infect various tissues (e.g., brain, muscle). 5. Tachyzoites transform into bradyzoites, forming tissue cysts. Transmission:   Contaminated soil with cat feces ingested inadvertently.   Consumption of undercooked meat from animals grazing in contam

  Leishmania donovani: Life Cycle, Pathogenesis, Treatment Prevention and Diagnosis   Leishmania donovani: The Causative Agent of Kalaazar (Visceral Leishmaniasis) Lifecycle   Reservoir Hosts: Various mammals (e.g., dogs, foxes, rodents).   Vector: Female sandflies.    Require blood meals for egg maturation.    Ingest macrophages containing amastigotes when feeding on an infected host. Inside the Sandfly: 1. Amastigotes transform into promastigotes in the gut. 2. Promastigotes multiply and migrate to the pharynx and proboscis. 3. This process takes about 10 days. Transmission to Humans: 1. Sandfly bites human, injecting promastigotes. 2. Promastigotes are engulfed by macrophages. 3. Inside macrophages, promastigotes transform back into amastigotes. Within the Human Host: 1. Amastigotes evade destruction by preventing vacuolelysosome fusion. 2. Infect other macrophages and reticuloendothelial cells. Cycle Completion:   Another sandfly ingests

   Introduction ·          IgG/IgM antibodies occasionally coat red blood cells (RBCs) without causing agglutination due to their monomeric structure. ·          The small size of antibody molecules prevents cross-linked bridges formation. ·          Coombs, Mourant, and Race developed a test in 1945 to detect these non-agglutinating, coating antibodies.     Principle ·          RBCs coated with incomplete antibody (IgG) or C3 complement do not cause agglutination. ·          Coombs reagent contains antibodies against human IgG/IgM/complement. ·          Anti-Human Globulin (AHG) reacts with human globulin molecules, either bound to RBCs or free in serum.     FDA Licensed Antihuman Globulin Reagents - Polyspecific   1. Rabbit polyclonal: Contains anti-IgG and anti-C3d.   2. Rabbit/murine monoclonal blend. - Monospecific   1. Anti-IgG (Rabbit polyclonal): Contains anti-IgG with no anticomplement activity.   2. Anti-IgG (Gamma-done AHG): Murine monoclonal

Introduction ·          Immunoglobulins (Ig) or Antibodies: Gamma globulins produced by plasma cells, specific to antigens. ·          Respond to foreign proteins or complex molecules not accepted by the host. ·          Exist as approximately 20% of proteins in body fluids. ·          Functions: Antigen binding, complement fixation, facilitation of phagocytosis, neutralization of toxic substances.   Classification ·          Based on the molecular structure of their heavy chains. ·          Five classes: IgA (α), IgD (δ), IgE (ε), IgG (γ), IgM (µ). ·          Each class has unique roles and characteristics.   Immunoglobulin/Antibody Structure ·          Common biochemical structural configuration. ·          Glycoproteins made of light (L) and heavy (H) polypeptide chains. ·          Basic unit: Four polypeptide chains (two identical light chains and two identical heavy chains). ·          Simplest antibody: Y-shaped.   Antigen Binding Fragment (Fab)

  Introduction   Immunity: Resistance or defense against harmful agents/substances causing disease.   Immune System: Cells and molecules defending the body against environmental pathogens.   Antigen: Substance stimulating an immune response.   Antibodies: Proteins reacting to antigens.   Self vs NonSelf   Self: Cells, fluids, molecules, and structures from the host.   NonSelf: External substances, living organisms (parasites, fungi), nonliving toxins, or host derived genetic rearrangements.   Types of Immunity   Innate or Natural Immunity: Primary, nonspecific defense present at birth, not altered by repeated exposure.   Acquired or Adaptive Immunity: Specific, acquired through contact with foreign substances, has memory improving response with each encounter.   Innate Immunity   First Line of Defense: Physical barriers like intact skin, mucous membranes.   Second Line of Defense: Cellular components like phagocytic cells, macrophages, NK cells, and hum

Introduction -           Blood is a mixture of cells, colloids, and crystalloids. -           Can be separated into different components: -           Packed Red Blood Cells (pRBC) -           Platelet Concentrate -           Fresh Frozen Plasma -           Cryoprecipitate   Component Separation Process -           Components separated based on: -           Relative density -           Sediment rate -           Size -           Centrifugal force is applied for separation. -           Each component is used for specific indications.   Importance of Component Separation -           Maximizes the utility of one whole blood unit. -           Provides different components for various therapeutic needs. -           Enhances efficiency and effectiveness of blood transfusions.   Storage and Temperature Requirements -           Different components have specific storage conditions. -           Temperature requirements vary for therapeutic efficacy.