Immunity Science Quiz

Second-generation H1 antihistamines are relatively free of adverse effects. This means that compared to first-generation H1 antihistamines, second-generation antihistamines have fewer side effects. This is an important characteristic when considering the use of antihistamines, as adverse effects can impact a person's overall well-being and quality of life.

The young man's symptoms of nasal congestion, sneezing, and watery eyes suggest an allergic reaction, commonly known as hay fever. These symptoms are caused by the release of chemical mediators, such as histamine, from mast cells. Mast cells are abundant in the nasal passageways and are known to be involved in allergic reactions. The fact that the symptoms improve with the use of loratadine, an antihistamine, further supports the involvement of mast cells in this case. Therefore, mast cells are the most likely cell type responsible for the young man's symptoms.

The skin prick test is the most commonly used and helpful test in routine clinical practice for identifying allergens. It involves pricking the skin with a small amount of allergen extract and observing for any allergic reaction, such as redness or swelling. This test is effective in diagnosing allergies to airborne substances, such as pollen, which could be the cause of the patient's symptoms during spring. The other options, such as allergen application on the skin, patch test, and intradermal skin test, are not as commonly used for identifying airborne allergens.

Facial-area furuncles are sometimes called "malignant" because they can lead to serious complications such as meningitis and sinus cavernous thrombosis. These conditions can be life-threatening and require immediate medical attention. The presence of furuncles in the facial area increases the risk of infection spreading to the brain and other vital structures, leading to potentially severe consequences. Therefore, it is important to treat facial-area furuncles promptly to prevent these complications.

The correct answer is A- Reed-Sternberg giant cell, B-Hodgkin cell. The structures marked by the green arrows in the microscopic image are most likely Reed-Sternberg giant cells and Hodgkin cells.

Converting a toxin to a toxoid reduces the toxic activity of the toxin. This is because a toxoid is a modified form of the toxin that has been treated to eliminate or reduce its toxicity while still retaining its ability to stimulate an immune response. By reducing the toxic activity of the toxin, the toxoid can be used as a vaccine to induce an immune response without causing harm to the individual.

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Anaphylaxis is a severe allergic reaction that typically involves multiple body systems. It can affect the skin, respiratory system, cardiovascular system, gastrointestinal system, and nervous system. It is characterized by a rapid onset, usually occurring within minutes to a few hours after exposure to an allergen. Symptoms may include hives, swelling, difficulty breathing, low blood pressure, vomiting, and dizziness. Bleeding from the nose is not a characteristic of anaphylaxis, and enlargement of the spleen and lymph nodes is not present in all cases. Arthralgia or joint swelling may or may not be present in anaphylaxis.

The patient's symptoms, including the delayed onset of the rash, its gradual increase in intensity, and its eventual fading away after two weeks, are consistent with a Type IV hypersensitivity reaction. Type IV hypersensitivity is a cell-mediated immune response that involves the activation of T cells. In this case, it is likely that the patient was exposed to an allergen during the hike, which triggered a delayed hypersensitivity reaction. The reaction is characterized by the recruitment of inflammatory cells, causing the rash.

Ludwig's angina is a serious infection of the floor of the mouth, usually caused by a dental infection. Odontogenic infection refers to infections originating from the teeth or oral cavity, and it is the most common cause of Ludwig's angina. Tongue piercing, parapharyngeal infection, tongue trauma, and tongue tumors are not typically associated with Ludwig's angina.

Reverse transcriptase is the correct answer because it is an enzyme that can synthesize DNA from an RNA template. This process is known as reverse transcription and is commonly found in retroviruses, which use reverse transcriptase to convert their RNA genome into DNA. Reverse transcriptase is also used in laboratory techniques such as reverse transcription polymerase chain reaction (RT-PCR) to convert RNA into complementary DNA (cDNA) for further analysis.

IL-12 is the correct answer because it promotes the differentiation of CD4 T cells into the effector Th1 cells. Th1 cells are known for their role in cell-mediated immunity and the production of pro-inflammatory cytokines. IL-12 stimulates the production of IFN-gamma, which is a key cytokine produced by Th1 cells. This cytokine helps in the activation of macrophages and enhances the immune response against intracellular pathogens.

The girl's symptoms of diarrhea after eating seafood and the resolution of symptoms within 3 hours suggest an immediate hypersensitivity reaction, which is characteristic of localized anaphylaxis. This type of reaction occurs when an allergen, in this case seafood, triggers the release of histamine and other inflammatory mediators, leading to symptoms such as diarrhea. The absence of abnormal findings on physical examination suggests that the reaction is localized rather than systemic.

The classical complement pathway is initiated by the formation of antibody-antigen complexes. When antibodies bind to antigens, they can activate the complement system. This triggers a cascade of enzymatic reactions that leads to the formation of the membrane attack complex, which can destroy the target cell. This pathway is an important part of the immune response against pathogens.

CD8 CTLs are capable of killing infected CD4 T cells, so the statement "They cannot kill infected CD4 T cells" is incorrect. Additionally, CD8 CTLs do need to be activated before they can exert their cytotoxic function, so the statement "They don't need to be activated before exerting their cytotoxic function" is also incorrect.

MHC class I molecules are important for binding to CD8 molecules on T cells and presenting endogenous antigens to cytotoxic T cells. These interactions are crucial for the activation of cytotoxic T cells, which play a key role in immune responses against infected or cancerous cells. By binding to CD8 molecules, MHC class I molecules facilitate the recognition of infected or abnormal cells by cytotoxic T cells. Additionally, by presenting endogenous antigens, MHC class I molecules help cytotoxic T cells identify and eliminate these abnormal cells.

HIV-1 is characterized by being a global pandemic. This means that it has spread widely across the world, affecting various regions and populations. The term "pandemic" refers to a disease that has reached epidemic proportions on a global scale, indicating that HIV-1 has become a significant public health concern affecting numerous countries and populations worldwide.

Serum sickness is a type III hypersensitivity reaction that occurs in response to the administration of certain medications or the injection of foreign proteins, such as antiserum. It is characterized by symptoms such as fever, malaise, and the enlargement of lymph nodes. These symptoms are indicative of an immune response and inflammation in the body. The other options mentioned in the question are not specific to serum sickness and do not align with its characteristic symptoms.

IgA is the most abundant class of immunoglobulins in bodily secretions. It is found in high concentrations in mucosal areas such as the respiratory tract, gastrointestinal tract, and genitourinary tract. IgA plays a crucial role in preventing the attachment and invasion of pathogens at these mucosal surfaces, providing a first line of defense against infections. It is also involved in neutralizing toxins and allergens. IgA is produced by plasma cells in the mucosal tissues and is transported across epithelial cells to be released into bodily secretions.

Betamethasone is the most likely drug that was given to the first-time mother to mature the fetal lungs. This is because betamethasone is a corticosteroid that is commonly used in obstetrics to promote fetal lung maturation in cases of preterm labor. It helps to accelerate the production of surfactant in the lungs, which is essential for the proper functioning of the lungs after birth. The other options, such as acetylsalicylic acid, indomethacin, ketorolac, and celecoxib, are not typically used for this purpose in obstetrics.

The radiologic features of lymphadenopathy in primary tuberculosis include enlarged hilar and paratracheal lymph nodes, which are typically unilateral and right-sided. This means that the lymph nodes in the chest area near the trachea and around the lung hilum become enlarged in tuberculosis. X-ray and CT scans are not informative in diagnosing primary tuberculosis, and resolution of lymphadenopathy can be seen after treatment. The statement "never occurs in children" is incorrect, as primary tuberculosis can occur in individuals of any age.

The main cofactors of anaphylaxis are exercise and emotional stress. These factors can trigger anaphylactic reactions in individuals who are already sensitized to certain allergens. Exercise-induced anaphylaxis is a condition where physical activity leads to an allergic reaction, while emotional stress can also contribute to the severity of anaphylactic symptoms. Other factors such as air pollution, hyperlipidemia, and smoking may have an impact on overall health but are not directly linked to anaphylaxis.

Active fragments of C5a can lead to contraction of smooth muscle, vasodilation, and attraction of leukocytes. However, opsonization of cells and attachment of lymphocytes to macrophages are not processes that are directly mediated by C5a.

The first antibody is able to react with the denatured TT because it recognizes the primary amino acid sequence of TT, which remains intact even when the disulfide bonds are disrupted. On the other hand, the second antibody is specific for conformational determinants, which are disrupted when the disulfide bonds are disrupted. Therefore, the second antibody fails to react with the denatured TT.

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Post-primary pulmonary tuberculosis is characterized by cavitation, which is the formation of cavities or hollow spaces in the lung tissue. This is the hallmark feature of this stage of tuberculosis. Additionally, patchy consolidation in the upper lobes of the lungs is commonly seen in post-primary tuberculosis. However, large self-limited bilateral pleural effusions are not always present in this stage, and bilateral involvement of the upper lung lobes can occur. The most common outcome of post-primary tuberculosis is resolution without any long-term complications or sequelae.

The visceral surface of the spleen has impressions from the left kidney, stomach, and colon. This means that these organs are in close proximity to the spleen and may leave indentations or markings on its surface. The liver, duodenum, and right kidney do not have their impressions on the visceral surface of the spleen.

The side effects of dry mouth, constipation, difficulty urinating, and increased appetite are consistent with the blockade of M cholinergic receptors and serotonergic receptors. M cholinergic receptors are involved in the regulation of salivation, gastrointestinal motility, and urinary function, so their blockade can lead to dry mouth, constipation, and difficulty urinating. Serotonergic receptors are involved in the regulation of appetite, so their blockade can lead to increased appetite. Therefore, the side effects described in the patient are likely due to the blockade of M cholinergic and serotonergic receptors.

Injection of endotoxin into an animal stimulates various responses, including activation of the Hageman factor leading to intravascular coagulation and hemorrhage, an inflammatory response resulting in fever, opsonized bacteria and activation of phagocytosis of macrophages, and activation of complement leading to inflammation. However, endotoxin injection does not directly result in the production of long duration antibodies. Antibody production is typically a result of an adaptive immune response, which takes time to develop and is not an immediate response to endotoxin injection.

The presence of multiple necrotic vascular walls replaced by smudgy, pink "fibrinoid" material in the kidneys suggests that there is inflammation and tissue injury occurring. This type of morphologic change is commonly associated with immune complex-mediated inflammation and tissue injury. Immune complexes are formed when antibodies bind to antigens, leading to the activation of inflammatory pathways and subsequent tissue damage. Therefore, the most likely pathogenesis mechanism for the morphologic changes in the patient's kidneys is immune complex-mediated inflammation and tissue injury, which is supported by the formation of immune complexes.

The correct diagnosis is Pandactilitis. The patient presents with symptoms of fever, redness, swelling, and intense pain in the finger, which are consistent with an infection. The fact that the finger is swollen, red, very painful, and has fluctuation suggests an abscess formation. Pandactilitis refers to an infection involving multiple structures of the finger, including the skin, subcutaneous tissue, and deep structures such as the tendon sheaths. This diagnosis is more appropriate than the other options, which refer to infections limited to specific structures such as the nail (Panaritium subunguale) or the skin (Panaritium subcutaneum and Panaritium cutaneum).

The morphologic features visible in the bone marrow biopsy, along with the patient's clinical symptoms, suggest that the most likely cause of the patient's pathology is intoxication by alkylating chemical agents and whole-body irradiation. This is because both of these factors can cause bone marrow suppression, leading to symptoms such as weakness, dyspnea, and susceptibility to respiratory infections. The morphologic features seen in the biopsy may also be consistent with the effects of these agents on the bone marrow.

Individuals with an undeveloped thymus would be expected to have a disturbed immune response and diminished number of cells in the periarterial lymphoid sheath in the spleen and the paracortex of the lymph node. The thymus plays a crucial role in the development and maturation of T cells, which are important for immune response. Without a properly developed thymus, the production and function of T cells would be compromised, leading to a decreased number of cells in these regions. The other options listed, such as fenestrated capillaries of bone marrow, germinal centers of primary lymphoid nodules, splenic trabeculae, and medulla of the lymph node, are not directly affected by thymus development.

Acetylsalicylic acid, also known as aspirin, can cause a rare but serious condition called Reye's syndrome in children with viral infections, such as influenza. Reye's syndrome is characterized by liver and brain damage, which can lead to coma and death. The symptoms of Reye's syndrome include high fever, fatty infiltration of the liver, and cerebral edema, which are consistent with the autopsy findings in the case of the 5-year-old boy. Therefore, acetylsalicylic acid is the medication that could cause death in this scenario.

Haptens are substances, usually of low molecular weight, that require carrier molecules to be immunogenic. They can stimulate secondary antibody responses without carriers. They interact with specific antibody only when conjugated with a high-molecular weight carrier.

The correct answer is Ultrasound-guided puncture and drainage and CT guided drainage. These methods involve using imaging techniques such as ultrasound or CT scans to guide the puncture and drainage of an abscess. This ensures accurate placement of the needle and helps to avoid damaging surrounding tissues. By using these closed methods, the abscess can be effectively drained without the need for open surgery, reducing the risk of complications and promoting faster healing.

Clostridium difficile causes diarrhea after antibiotic therapy because its spores are resistant to most common antibiotics. Additionally, antibiotics disrupt the normal gut flora, which allows for the overgrowth of C. difficile. Moreover, antibiotics can injure the epithelium of the intestines and increase sensitivity to bacterial toxins.

The correct answer is 1. A and B, 2. Immunohistochemical reaction. Based on the clinical history of chronic osteomyelitis of the right femoral bone, the morphologic features and anatomical sites of the observed lesions in images A and B are most likely direct complications of the osteomyelitis. The immunohistochemical reaction is the most likely method to confirm these images as complications, as it can help identify specific markers or antigens associated with the inflammatory process in the affected tissues. The congo red testing is not relevant to confirming the complications of chronic osteomyelitis.

The cisterna chyli is a lymphatic structure that collects lymph from various parts of the body. In this case, it collects lymph from the small intestine, liver, and right lower limb. The small intestine is a major site of nutrient absorption and lymphatic vessels in this area help transport absorbed fats and fat-soluble vitamins. The liver is involved in various metabolic processes and produces lymph that contains waste products. The right lower limb has lymphatic vessels that drain lymph from the leg and foot.

The correct answer is Ibuprofen. Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that can be prescribed for pain relief in patients with osteoarthritis. It is a commonly used NSAID and is generally well-tolerated. The patient's history of bleeding from a stomach ulcer 6 months ago is important to consider, as some NSAIDs can increase the risk of gastrointestinal bleeding. However, Ibuprofen is considered to have a lower risk of causing stomach ulcers compared to other NSAIDs, making it a suitable choice for this patient.

The presence of marked icterus and a low hemoglobin level suggests that the baby is experiencing hemolytic anemia. The fact that the baby required an exchange transfusion further supports this. The most likely immunological mechanism causing this is the production of anti-receptor antibodies by the fetus. These antibodies can bind to receptors on the baby's red blood cells, leading to their destruction and subsequent anemia. This condition is known as immune-mediated hemolytic disease of the newborn.

Macrophages are located in the stroma of reticular cells and reticular fibers and filter the blood in the cortex of the thymus.

Hyperbaric oxygen therapy (HBO) and urgent necrosectomy are the treatment components that have the greatest impact on outcomes in necrotizing soft tissue infections (NSTIs). HBO therapy involves delivering 100% oxygen at high pressure, which helps improve tissue oxygenation and promote wound healing. Urgent necrosectomy refers to the surgical removal of necrotic (dead) tissue, which is crucial in preventing the spread of infection and promoting healing. These interventions are considered essential in the management of NSTIs and have been shown to significantly improve patient outcomes.

The correct answer is histamine and neutrophilic granulocytes chemotactic factor. Histamine is released by mast cells during inflammation and causes vasodilation and increased vascular permeability. Neutrophilic granulocytes chemotactic factor attracts neutrophils to the site of inflammation. Both of these factors play a role in the early stages of inflammation and can be observed in the electron microscopy images presented.

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IgM is the correct answer because it is the only immunoglobulin that can form a pentameric structure. IgM is the first antibody produced during an immune response and its pentameric structure allows for increased binding capacity and efficient neutralization of pathogens. IgE, IgA, IgD, and IgG all have different structures and functions.

The correct answer is "Gram-positive rods that colonize animal and human intestines" and "Tetanus toxin prevent release of acetylcholine at peripheral cholinergic synapse". These statements accurately describe the infection agent of tetanus. Tetanus is caused by a bacterium called Clostridium tetani, which is a gram-positive rod-shaped bacterium that can colonize the intestines of animals and humans. The bacterium produces a neurotoxin called tetanus toxin, which prevents the release of acetylcholine at peripheral cholinergic synapses. This leads to muscle stiffness and spasms, characteristic symptoms of tetanus.