Platelet activating factor is: a. Generated by the action of phospholipase A2 on membrane phospholipids b. Antiinflammatory in most of its actions c. Synthesized by endothelial and other cells d. Exerts a variety of biologic effects which are platelet-independent

Platelet activating factor is: a. Generated by the action of phospholipase A2 on membrane phospholipids b. Antiinflammatory in most of its actions c. Synthesized by endothelial and other cells d. Exerts a variety of biologic effects which are platelet-independent
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Answer: a, c, d  Like the eicosanoids, platelet-activating factor (PAF) is not stored in cells but is rapidly produced during inflammation. PAF exerts a variety of biologic effects that are platelet-independent. The synthesis of PAF is initiated by the activation of phospholipase A2. Activation of phospholipase A2 releases arachidonic acid in addition to lyso-PAF. Hence, PAF synthesis and eicosanoid production are coordinately regulated. PAF is synthesized on activation of a variety of inflammatory cells including platelets, neutrophils, basophils, mast cells, mononuclear phagocytes, eosinophils and vascular endothelium. PAF is a stimulatory agonist for many inflammatory cells, as well as for smooth muscle cells, vascular endothelium and others. PAF enhances the ability of neutrophils to respond to challenge with N-formylpeptides and LTB4. There is considerable overlap and redundancy in the effects produced by PAF and eicosanoids
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Which of the following statement(s) is/are correct concerning the immunoinflammatory response to shock? a. The anaphylactoxins, C3a and C5a, are products of activation of only the classical pathway of the compliment cascade b. Eicosanoids, such as prostaglandins are stored in platelets and endothelial cells and released in response to inflammatory stimuli c. Thromboxane and PGI2 have similar effects d. Platelet-activating factor can be released by both circulating and fixed tissue cells

Description : Which of the following statement(s) is/are correct concerning the immunoinflammatory response to shock? a. The anaphylactoxins, C3a and C5a, are products of activation of only the classical pathway ... effects d. Platelet-activating factor can be released by both circulating and fixed tissue cells

Last Answer : Answer: d Inflammatory mediators have recently been recognized as playing a significant role in the clinical manifestations and progression of shock and the development ... increased pulmonary vascular resistance, bronchoconstriction, peripheral vasodilatation, and increased vascular permeability

Which of the following statements regarding cytokines is incorrect? A. Cytokines act directly on target cells and may potentiate the actions of one another. B. Interleukin 1 (IL-1) is a major proinflammatory mediator with multiple effects, including regulation of skeletal muscle proteolysis in patients with sepsis or significant injury. C. Platelet-activating factor (PAF) is a major cytokine that results in platelet aggregation, bronchoconstriction, and increased vascular permeability. D. Tumor necrosis factor alpha (TNF-a), despite its short plasma half-life, appears to be a principal mediator in the evolution of sepsis and the multiple organ dysfunction syndrome because of its multiple actions and the secondary cascades that it stimulates.

Description : Which of the following statements regarding cytokines is incorrect? A. Cytokines act directly on target cells and may potentiate the actions of one another. B. Interleukin 1 (IL-1) ... organ dysfunction syndrome because of its multiple actions and the secondary cascades that it stimulates.

Last Answer : Answer: C DISCUSSION: Cytokines are soluble peptide molecules that are synthesized and secreted by a number of cell types in response to injury, inflammation, and infection. Cytokines, which ... is thought to play a central role in the stress response, particularly in response to endotoxemia

Cytokines are low-molecular-weight polypeptides exerting a wide variety of biologic effects at both local and systemic levels. Which of the following statement(s) is/are true concerning the production and actions of cytokines? a. Cytokines are produced solely by macrophages b. Cytokines act only on other cells within the same local environment c. Cytokines may have both protective and deleterious effects on the host d. Each specific cytokine is produced by a single cell type

Description : Cytokines are low-molecular-weight polypeptides exerting a wide variety of biologic effects at both local and systemic levels. Which of the following statement(s) is/are true concerning the production and ... effects on the host d. Each specific cytokine is produced by a single cell type

Last Answer : Answer: c Macrophages, endothelial cells, lymphocytes, and other cells secrete a large number of different compounds, termed cytokines, that are most probably evolved for the purpose of ... host defenses, exerting both salutatory and deleterious effects on the host, has become increasingly evident

True statements regarding eicosanoids include which of the following? A. Prostaglandins and thromboxanes are synthesized via the cyclo-oxygenase pathway. B. The vasoconstricting, platelet-aggregating, and bronchoconstricting effects of thromboxane A 2 are balanced by the actions of prostacyclin, which produces the opposite effects. C. Leukotriene synthesis is inhibited by the action of nonsteroidal anti-inflammatory drugs (NSAIDs). D. The principal prostaglandins have a short circulation half-life and exert most of their effects locally.

Description : True statements regarding eicosanoids include which of the following? A. Prostaglandins and thromboxanes are synthesized via the cyclo-oxygenase pathway. B. The vasoconstricting, platelet-aggregating, ... prostaglandins have a short circulation half-life and exert most of their effects locally.

Last Answer : Answer: ABD DISCUSSION: The eicosanoids are a group of compounds arising from the metabolism of arachidonic acid. The prostaglandins and thromboxanes are synthesized via the cyclo-oxygenase ... effects and may be involved in the physiologic responses associated with anaphylactic and septic shock

Which of the following statements regarding IL-1 are correct? a. While IL-1 and TNFa share many biologic effects, IL-1 appears to be more potent b. IL-1 expression is in part autoregulated c. IL-1 inhibits prostaglandin production d. The ability of IL-1 to upregulate endothelial cell-neutrophil adhesion molecules is relatively limited

Description : Which of the following statements regarding IL-1 are correct? a. While IL-1 and TNFa share many biologic effects, IL-1 appears to be more potent b. IL-1 expression is in part ... production d. The ability of IL-1 to upregulate endothelial cell-neutrophil adhesion molecules is relatively limited

Last Answer : Answer: b IL-1 and TNFa share many biologic properties. In addition, each potentiates the effects of the other one when given concurrently. Overall, IL-1 alone probably has weaker effects than ... IL-1 provides a key step in the extravasation of leukocytes to sites of local inflammation and injury

A striking feature of living cells is a marked difference between the composition of the cytosol and the extracellular milieu. Which of the following statement(s) concerning the mechanisms of maintenance of these differences is/are true? a. The cell membrane is able to maintain a 10,000 fold gradient between the extracellular concentration of ionized calcium and the intracellular concentration b. The key to these differences is the fact that the plasma membrane is normally impermeable to sodium, potassium and calcium c. The selectivity of biologic membranes is highly consistent and seldom changes d. The selectivity of cell membranes relates only to ions and not organic compounds

Description : A striking feature of living cells is a marked difference between the composition of the cytosol and the extracellular milieu. Which of the following statement(s) concerning the mechanisms of maintenance ... d. The selectivity of cell membranes relates only to ions and not organic compounds

Last Answer : Answer: a The survival of the cell requires that cytosolic composition be maintained within narrow limits, despite the constant influx of nutrients and the simultaneous outflow of waste. A ... be altered drastically as a result of regulatory or signaling processes that occur within the cell

Cytokines with clearly defined actions in acute inflammation and early tissue injury include which of the following? a. Cysteine-X-Cysteine (C-X-C) chemokines b. Tumor Necrosis Factor (TNFa) c. Transforming Growth Factor-b (TGF-b) d. Interleukin-6 (IL-6) e. Platelet Derived Growth Factor (PDGF)

Description : Cytokines with clearly defined actions in acute inflammation and early tissue injury include which of the following? a. Cysteine-X-Cysteine (C-X-C) chemokines b. Tumor Necrosis Factor (TNFa) c. Transforming Growth Factor-b (TGF-b) d. Interleukin-6 (IL-6) e. Platelet Derived Growth Factor (PDGF)

Last Answer : Answer: a, b, c, d, e Polypeptide mediators, such as TNFa and IL-1, are considered early response cytokines and are actively involved in the initiation of the ... of tissue repair. Thus, coagulation and platelet activation provide the initial foundation for subsequent cellular recruitment

Low doses of aspirin prolong bleeding time by selectively inhibiting synthesis of the following mediator in the platelets: A. Thromboxane A2 B. 5-Hydroxytryptamine C. Platelet activating factor D. Prostacyclin

Description : Low doses of aspirin prolong bleeding time by selectively inhibiting synthesis of the following mediator in the platelets: A. Thromboxane A2 B. 5-Hydroxytryptamine C. Platelet activating factor D. Prostacyclin

Last Answer : A. Thromboxane

Which of the following statements are true of oxidants? A. In addition to their pathophysiologic roles in inflammation, injury, and infection, oxidants also have physiologic roles. B. Oxidants may be generated from activated neutrophils and during reperfusion following a period of ischemia. C. The deleterious effects of oxidants include lipid peroxidation and cell membrane damage, oxidative damage to DNA, and inhibition of adenosine triphosphate (ATP) synthesis. D. The mechanism of ischemia-reperfusion injury involved the catalytic production of superoxide anion (O 2•) by the enzyme xanthine oxidase.

Description : Which of the following statements are true of oxidants? A. In addition to their pathophysiologic roles in inflammation, injury, and infection, oxidants also have physiologic roles. B. Oxidants may ... involved the catalytic production of superoxide anion (O 2 ) by the enzyme xanthine oxidase.

Last Answer : Answer: ABCD DISCUSSION: Oxidants are reactive oxygen metabolites that have both physiologic and pathophysiologic roles. As potent oxidizing agents, oxidants are involved in cytochrome P ... leukocyte infiltration and activation, causing further tissue damage by the release of cytotoxic proteases

Increasing evidence has implicated gram-negative bacterial lipopolysaccharide (LPS endotoxin) as the portion of the gram-negative bacterial cell membrane responsible for many, if not all the toxic effects that occur during gram-negative bacterial sepsis. The following statement(s) is/are true concerning LPS and the host response. a. The LPS molecule can in itself cause physiologic responses similar to that seen during gram-negative bacterial sepsis b. LPS triggers host macrophages to release a variety of cytokines including TNF-a, IL-1a, and IL-1b, IL-6, and IFN-a c. Excessive cytokine production is not associated with detrimental consequences d. TNFa and IL-1b appear to be the primary mediators within the host, exerting deleterious effects on the host when excessive amounts reach the syst

Description : Increasing evidence has implicated gram-negative bacterial lipopolysaccharide (LPS endotoxin) as the portion of the gram-negative bacterial cell membrane responsible for many, if not all the ... host, exerting deleterious effects on the host when excessive amounts reach the systemic circulation

Last Answer : Answer: a, b, d The LPS molecule exerts diverse effects on the mammalian host. Immunologic responses to LPS include nonspecific polyclonal B-cell proliferation, macrophage activation and ... deleterious effects on the host only after large amounts are secreted and reach the systemic circulation

Answer: a, b, c, d Free oxygen radicals are chemical species that are intermediates in the normal process of cellular respiration. Oxidants that are free radicals have been implicated as initiators of reactions which lead to a variety of cellular injuries. Oxidants are derived from several sources, notably phagocytes. Among the effects of oxygen free radicals are membrane lipid peroxidation, DNA strand breaks, cytoskeletal disassembly and inhibition of glucose metabolism leading to decreased cellular ATP concentrations. (Figure 6-16) 187 Which of the following acute-phase protein levels are increased in human plasma following acute inflammation? a. C-reactive protein b. Serum amyloid c. a -Proteinase inhibitor d. Fibrinogen e. Albumin

Description : Answer: a, b, c, d Free oxygen radicals are chemical species that are intermediates in the normal process of cellular respiration. Oxidants that are free radicals have been implicated as initiators of ... a. C-reactive protein b. Serum amyloid c. a -Proteinase inhibitor d. Fibrinogen e. Albumin

Last Answer : Answer: a, b, c, d The acute-phase response is a series of homeostatic responses of the organism to tissue injury in infection and inflammation. After an inflammatory stimulus occurs, a number ... 30% to 50% of the level before injury. The reason for the decrease in production is poorly understood

The actions of platelet activating factor include the following except: A. Increased capillary permeability B. Bronchodilatation C. Vasodilatation D. Erosion of gastric mucosa

Description : The actions of platelet activating factor include the following except: A. Increased capillary permeability B. Bronchodilatation C. Vasodilatation D. Erosion of gastric mucosa

Last Answer : B. Bronchodilatation

Which of the following statement(s) is/are true concerning ischemia reperfusion injury? a. During ischemia, ATP degradation results in increased plasma and intracellular levels of hypoxanthine and xanthene b. Oxygen free radicals such as the superoxide radical are involved in the expression of the proinflammatory phenotype of endothelial cells, macrophages and neutrophils c. The intracellular adhesion molecule-1 (ICAN-1) contributes to injury and disruption of the endothelial lining, with extensive capillary leak and resultant interstitial edema d. Animal models have demonstrated that passive immunization with antibodies to neutrophil adhesive complex lessen the ischemic/reperfusion microvascular injury

Description : Which of the following statement(s) is/are true concerning ischemia reperfusion injury? a. During ischemia, ATP degradation results in increased plasma and intracellular levels of ... immunization with antibodies to neutrophil adhesive complex lessen the ischemic/reperfusion microvascular injury

Last Answer : Answer: a, b, c, d During the ischemia and hypoperfusion phase, degradation of ATP stores essential to maintain cell integrity and significant loss of diffusible ... either the neutrophil adhesive complex or the endothelial selectins dramatically lessens ischemia/reperfusion microvascular injury

Which of the following statement(s) is/are true concerning the pulmonary response to shock? a. The acute pulmonary vascular response to shock differs markedly from that of systemic vasculature b. The pulmonary edema of ARDS occurs in the face of elevated left heart pressures c. The initial physiologic changes of ARDS involve the capillary endothelial cells and the type I pneumocyte d. Mechanisms proposed in the pathogenesis of ARDS include injury from mediators of inflammation elsewhere and from activated cellular elements e. A decrease in lung compliance may result from the loss of type I pneumocytes

Description : Which of the following statement(s) is/are true concerning the pulmonary response to shock? a. The acute pulmonary vascular response to shock differs markedly from that of systemic vasculature b. The ... elements e. A decrease in lung compliance may result from the loss of type I pneumocytes

Last Answer : Answer: c, d, e Contributing pathophysiologic processes to the pulmonary manifestations of shock include the pulmonary component of the cardiovascular response, disruption of the normal ... injury from mediators of inflammation elaborated elsewhere, and from activated cellular blood elements

Which of the following statements regarding endothelial cells in acute inflammation are true? a. Endothelial cells are characterized by phenotypic homogeneity b. Specific patterns of receptor expression regulate leukocyte adherence c. Endothelial cell nitric oxide generation regulates regional blood flow and leukocyte adhesion d. Endothelial cells may be capable of phagocytosis

Description : Which of the following statements regarding endothelial cells in acute inflammation are true? a. Endothelial cells are characterized by phenotypic homogeneity b. Specific patterns of receptor expression ... blood flow and leukocyte adhesion d. Endothelial cells may be capable of phagocytosis

Last Answer : Answer: b, c, d Endothelial cells are increasingly recognized to be phenotypically heterogeneous. Specific receptor molecules are expressed at various sites where they help to direct lymphocytes and ... rather, they possess the ability to direct and focus many aspects of an inflammatory event

Leukocyte activation and adhesion to vascular endothelial cells is a critical step in the inflammatory process. This process is regulated by which of the following molecules? a. The selectins b. The b5 integrins c. The immunoglobulin supergene family d. Nitric oxide e. IL-8

Description : Leukocyte activation and adhesion to vascular endothelial cells is a critical step in the inflammatory process. This process is regulated by which of the following molecules? a. The selectins b. The b5 integrins c. The immunoglobulin supergene family d. Nitric oxide e. IL-8

Last Answer : Answer: a, c, d, e The temporal events that initiate and propagate neutrophil recruitment and inflammation include endothelial cell activation and expression of endothelial-derived ... role in neutrophil recruitment and activation, and the continued propagation of the inflammatory response

Which of the following statement(s) is/are true concerning the proliferative phase of wound healing? a. The macrophage is the predominant cell type b. The pink or purple-red appearance of a wound is due to ingrowth and proliferation of endothelial cells c. Collagen, the dominant structural molecule of the wound matrix, contains two unique amino acids, hydroxyproline and hydroxylysine d. The predominant collagen type in a scar is type 3

Description : Which of the following statement(s) is/are true concerning the proliferative phase of wound healing? a. The macrophage is the predominant cell type b. The pink or purple-red appearance of a wound ... amino acids, hydroxyproline and hydroxylysine d. The predominant collagen type in a scar is type 3

Last Answer : Answer: b, c The proliferative phase of wound healing begins with the formation of a provisional matrix of fibrin and fibronectin as part of the initial clot formation. Initially, the provisional ... The principal collagen type scar is type 1, with lesser amounts of type 3 collagen also present

Proteins formed when cells are exposed to viral or foreign agents that are capable of activating other components of the immune system are referred to as a) interferons. Interferons are biologic response modifiers with nonspecific viricidal proteins.

Description : Proteins formed when cells are exposed to viral or foreign agents that are capable of activating other components of the immune system are referred to as a) interferons. Interferons are biologic ... series of enzymatic proteins in the serum that, when activated, destroy bacteria and other cells.

Last Answer : a) interferons. Interferons are biologic response modifiers with nonspecific viricidal proteins.

Which of the following statements regarding angiogenesis are true? a. Angiogenesis is a seminal biologic event with clinical relevance limited to its effect upon tumor growth b. C-X-C chemokines regulate angiogenesis c. PF-4 has angiogenic properties d. Sites of atherosclerosis demonstrate chronic angiogenic activity

Description : Which of the following statements regarding angiogenesis are true? a. Angiogenesis is a seminal biologic event with clinical relevance limited to its effect upon tumor growth b. C-X-C ... c. PF-4 has angiogenic properties d. Sites of atherosclerosis demonstrate chronic angiogenic activity

Last Answer : Answer: b, d An important component of tissue repair and wound healing is the process of angiogenesis. This normal, physiologic process is a local, transient event which is ... between these factors may govern overall angiogenic potential in a variety of physiological and pathophysiological states

Mini-dose heparin has been shown to be useful in the prophylaxis of postoperative venous thrombosis. Mechanism(s) by which low-dose heparin is/are thought to protect against venous thrombosis include: a. Enhancement of antithrombin III activity b. A decrease in thrombin availability c. Inhibition of platelet aggregation and subsequent platelet release action d. A mild prolongation of activated partial thromboplastin time

Description : Mini-dose heparin has been shown to be useful in the prophylaxis of postoperative venous thrombosis. Mechanism(s) by which low-dose heparin is/are thought to protect against venous ... aggregation and subsequent platelet release action d. A mild prolongation of activated partial thromboplastin time

Last Answer : Answer: a, b, c Low-dose heparin is thought to protect against venous thrombosis through three different mechanisms. First, antithrombin III activity with its inhibition of activated Factor X is ... release reaction. The standard doses of heparin administered (5000 units bid) does not affect aPTT

Montelukast blocks the action of the following autacoid: A. Prostacyclin B. Platelet activating factor C. Leukotriene B4 D. Leukotriene C4/D4

Description : Montelukast blocks the action of the following autacoid: A. Prostacyclin B. Platelet activating factor C. Leukotriene B4 D. Leukotriene C4/D4

Last Answer : D. Leukotriene C4/D4

Which of the following substances, not normally present in the circulation, trigger the initiating events in the hemostatic process? a. Thrombin b. Platelet factor 3 c. Tissue factor d. Collagen

Description : Which of the following substances, not normally present in the circulation, trigger the initiating events in the hemostatic process? a. Thrombin b. Platelet factor 3 c. Tissue factor d. Collagen

Last Answer : Answer: c, d The initiating agents for hemostasis involve two substances that are not normally present in the circulation-collagen and tissue factor. Tissue factor is released from ... phospholipid surface to form the so-called prothrombinase complex which catalyzes the formation of thrombin

Which of the following statement(s) is/are true concerning hemophilia A? a. Hemophilia A is inherited as a sex-linked recessive deficiency of factor VIII b. A positive family history for bleeding disorders present in all patients c. Laboratory tests reveal a prolongation of aPTT, prothrombin time (PT), thrombin clotting time and platelet aggregation d. Spontaneous bleeding is unusual with factor VIII levels greater than 10% of normal

Description : Which of the following statement(s) is/are true concerning hemophilia A? a. Hemophilia A is inherited as a sex-linked recessive deficiency of factor VIII b. A positive family history for ... platelet aggregation d. Spontaneous bleeding is unusual with factor VIII levels greater than 10% of normal

Last Answer : Answer: a, d Hemophilia A is inherited as a sex-linked recessive deficiency of factor VIII although 0% of cases are secondary to spontaneous mutation. The incidence of this abnormality is ... factor levels as low as 1% have been noted and patients are at risk for spontaneous bleeding

Which of the following statement(s) is/are true concerning pharmacologic agents used to accelerate wound healing? a. A number of these agents are now currently approved for use in this country b. PDGF (platelet-derived growth factor) promotes fibroblast proliferation, chemotaxis, and collagenase synthesis c. PDGF has been demonstrated in a number of clinical trials to promote healing in chronic wounds d. Growth hormone functions by promoting fibroblast proliferation and collagen synthesis

Description : Which of the following statement(s) is/are true concerning pharmacologic agents used to accelerate wound healing? a. A number of these agents are now currently approved for use in ... healing in chronic wounds d. Growth hormone functions by promoting fibroblast proliferation and collagen synthesis

Last Answer : Answer: b, c Currently there are no approved clinical agents that accelerate normal healing. Although a number of clinical trials are in progress, no agents are currently ... hormone administration significantly accelerates donor site healing, presumably due to its effects in minimizing catabolism

Products of platelet degranulation include: a. Tumor necrosis factor b. Interleukin-1 c. Transforming growth factor b d. Platelet-derived growth factor

Description : Products of platelet degranulation include: a. Tumor necrosis factor b. Interleukin-1 c. Transforming growth factor b d. Platelet-derived growth factor

Last Answer : Answer: c, d The initial response to injury and disruption of a blood vessel is bleeding. The hemostatic response to this is clot formation to stop hemorrhage. Platelet plug ... . Tumor necrosis factor and interleukin-1 also stimulate fibroblast proliferation, however are produced by macrophages

Some hormones produce their intracellular effects by activating (A) Phospholipae A1 (B) Phospholipase B (C) Phospholipase C (D) All of these

Description : Some hormones produce their intracellular effects by activating (A) Phospholipae A1 (B) Phospholipase B (C) Phospholipase C (D) All of these

Last Answer : Answer : C

All of the following are true regarding platelet-activating factor (PAF) EXCEPT: C A. Induces platelet aggregation B. Stimulates platelet secretion C. It is a preformed molecule present in various cells D. None of these

Description : All of the following are true regarding platelet-activating factor (PAF) EXCEPT: C A. Induces platelet aggregation B. Stimulates platelet secretion C. It is a preformed molecule present in various cells D. None of these

Last Answer : It is a preformed molecule present in various cells

Corticosteroids exert antiinflammatory action by inhibiting the following enzyme: A. Cyclooxygenase B. Lipoxygenase C. Phospholipase-A D. Phosphodiesterase

Description : Corticosteroids exert antiinflammatory action by inhibiting the following enzyme: A. Cyclooxygenase B. Lipoxygenase C. Phospholipase-A D. Phosphodiesterase

Last Answer : C. Phospholipase-A

Neutrophil chemotaxis is a fundamental aspect of inflammatory injury in conditions such as the Adult Respiratory Distress Syndrome (ARDS). Neutrophil chemotaxis is directly attributable to which of the following molecules? a. C5a b. TNFa c. LPS d. IL-1 e. ENA-78 (Epithelial Neutrophil Activating Protein)

Description : Neutrophil chemotaxis is a fundamental aspect of inflammatory injury in conditions such as the Adult Respiratory Distress Syndrome (ARDS). Neutrophil chemotaxis is directly attributable to which of the following molecules? ... TNFa c. LPS d. IL-1 e. ENA-78 (Epithelial Neutrophil Activating Protein)

Last Answer : Answer: a, e There is a large collection of peptide, polypeptide and lipid mediators which have chemotactic properties. Although TNF a, IL-1 and LPS were initially reported to have direct ... are several complement-derived peptides. Perhaps, the most potent of these is the short-lived C5a peptide

The following is/are true of mesalazine: A. It exerts mainly local antiinflammatory action in the lower gut B. It is a broad spectrum antidiarrhoeal drug C. It can be administered as a retention enema D. Both 'A' and 'C

Description : The following is/are true of mesalazine: A. It exerts mainly local antiinflammatory action in the lower gut B. It is a broad spectrum antidiarrhoeal drug C. It can be administered as a retention enema D. Both 'A' and 'C

Last Answer : D. Both 'A' and 'C

What is true of nimesulide: A. It exerts antiinflammatory action by several mechanisms in addition to cyclooxygenase inhibition B. It is preferred for long-term use in rheumatoid arthritis C. It is contraindicated in aspirin intolerant asthma patients D. All of the above

Description : What is true of nimesulide: A. It exerts antiinflammatory action by several mechanisms in addition to cyclooxygenase inhibition B. It is preferred for long-term use in rheumatoid arthritis C. It is contraindicated in aspirin intolerant asthma patients D. All of the above

Last Answer : A. It exerts antiinflammatory action by several mechanisms in addition to cyclooxygenase inhibition

Lysolecithin is formed from lecithin by the action of (A) Phospholipase A1 (B) Phospholipase A2 (C) Phospholipase C (D) Phospholipase D

Description : Lysolecithin is formed from lecithin by the action of (A) Phospholipase A1 (B) Phospholipase A2 (C) Phospholipase C (D) Phospholipase D

Last Answer : Answer : B

The mechanism of action of cyclosporine involves (a) Activation of calcineurin (b) Binding to cyclophilin to cause inhibition of a cytoplasmic phosphatase (c) Blockade of interleukin – 2- receptors (d) Inhibition of phospholipase A2 (e) Suppression of bone marrow progenitors

Description : The mechanism of action of cyclosporine involves (a) Activation of calcineurin (b) Binding to cyclophilin to cause inhibition of a cytoplasmic phosphatase (c) Blockade of interleukin – 2- receptors (d) Inhibition of phospholipase A2 (e) Suppression of bone marrow progenitors

Last Answer : Ans: B

Thromboxane A2(TXA2): a. is derived from the membrane phospholipid b. its production is decreased by non-steroidal anti-inflammatory drugs c. causes platelet aggregation d. all above

Description : Thromboxane A2(TXA2): a. is derived from the membrane phospholipid b. its production is decreased by non-steroidal anti-inflammatory drugs c. causes platelet aggregation d. all above

Last Answer : all above

Selective COX-2 inhibitors differ from nonselective COX-1/COX-2 inhibitors in that they: A. Are antiinflammatory but not analgesic B. Donot bring down fever C. Have no renal effects D. Do not inhibit platelet aggregation

Description :  Selective COX-2 inhibitors differ from nonselective COX-1/COX-2 inhibitors in that they: A. Are antiinflammatory but not analgesic B. Donot bring down fever C. Have no renal effects D. Do not inhibit platelet aggregation

Last Answer : D. Do not inhibit platelet aggregation

Choose the correct statement about ticlopidine: A. It blocks GPIIb/IIIa receptors on platelet membrane B. It prevents ADP mediated platelet adenylylcyclase inhibition C. It inhibits thromboxane A2 synthesis in platelets D. It does not prolong bleeding time

Description : Choose the correct statement about ticlopidine: A. It blocks GPIIb/IIIa receptors on platelet membrane B. It prevents ADP mediated platelet adenylylcyclase inhibition C. It inhibits thromboxane A2 synthesis in platelets D. It does not prolong bleeding time

Last Answer : B. It prevents ADP mediated platelet adenylylcyclase inhibition

Laboratory monitoring of coagulation and anticoagulation includes testing of platelet function. Which of the following statements is/are true concerning tests of platelet function? a. A platelet count of 50,000/µL or more usually ensures hemostasis b. Bleeding time assays assessibility of platelets to perform hemostatic plugs and is determined from a sample of blood drawn in an EDTA coated test tube c. Aspirin therapy can be associated with a bleeding time in the range of 8–15 minutes d. Tests of platelet aggregation should be part of the standard preoperative evaluation of patients using aspirin

Description : Laboratory monitoring of coagulation and anticoagulation includes testing of platelet function. Which of the following statements is/are true concerning tests of platelet function? a. A ... platelet aggregation should be part of the standard preoperative evaluation of patients using aspirin

Last Answer : Answer: a, c Tests of platelet function include peripheral platelet counts, bleeding times, and platelet aggregation. Usually, a platelet count of 50,000/mL or more ensures adequate hemostasis ... is not available in most laboratories, probably because of the observer-dependent nature of the test

A 67-year-old male with advanced cholangiocarcinoma develops gram-negative sepsis. Excessive bleeding is noted around vascular catheters and from needle puncture sites. The diagnosis of disseminated intervascular coagulation (DIC) is considered. Which of the following laboratory test(s) is/are indicative of DIC? a. Decreased platelet count b. Decreased fibrinogen level c. Normal prothrombin time d. Elevated fibrin split products

Description : A 67-year-old male with advanced cholangiocarcinoma develops gram-negative sepsis. Excessive bleeding is noted around vascular catheters and from needle puncture sites. The diagnosis of disseminated ... b. Decreased fibrinogen level c. Normal prothrombin time d. Elevated fibrin split products

Last Answer : Answer: a, b, d Disseminated intravascular coagulation (DIC) is the primary form of acute thrombosis. Causes of this syndrome include abruptio placenta, gram-positive and gram-negative sepsis, ... decline in the platelet count and fibrinogen level, along with an elevation of fibrin split products

Which of the following statement(s) is/are true concerning heparin-associated thrombocytopenia? a. Heparin-associated thrombocytopenia occurs only in the face of over anticoagulation with heparin b. Severe thrombocytopenia (platelet count less than 100,000) is seen in less than 10% of patients treated with heparin c. Heparin-associated thrombocytopenia is due to the aggregation of platelets and may result in thrombosis or embolic episodes d. Heparin-associated thrombocytopenia may be seen within hours of initiation of heparin therapy

Description : Which of the following statement(s) is/are true concerning heparin-associated thrombocytopenia? a. Heparin-associated thrombocytopenia occurs only in the face of over anticoagulation with heparin b. ... d. Heparin-associated thrombocytopenia may be seen within hours of initiation of heparin therapy

Last Answer : Answer: b, c Heparin-associated thrombocytopenia occurs in 0.6% to 30% of patients who receive heparin, although severe thrombocytopenia (platelet counts less than 100,000) is seen in ... as coating on pulmonary artery catheters or low rate infusion into arterial catheters may cause this syndrome

Which of the following statement(s) concerning laboratory studies used in monitoring a patient with intravenous heparinization is/are correct? a. The platelet count should be followed because of the risk of heparin-associated thrombocytopenia b. The prothrombin time should be observed if prolonged treatment is necessary c. The activated partial thromboplastin time (aPTT) should be maintained at approximately 1.5 times normal d. The serum creatinine should be measured daily to allow adjustments in dose based on renal function

Description : Which of the following statement(s) concerning laboratory studies used in monitoring a patient with intravenous heparinization is/are correct? a. The platelet count should be followed because of the ... serum creatinine should be measured daily to allow adjustments in dose based on renal function

Last Answer : Answer: a, c In monitoring the effect of heparin, an activated partial thromboplastin time (aPTT) of 1.5 control or a thrombin clotting time (TCT) of 2 times control reflects adequate ... system. Therefore the dose of heparin need not be adjusted in cases of liver or renal dysfunction

Which of the following cell types are not crucial for healing a clean, incisional wound? A. Macrophage. B. Platelet. C. Fibroblast. D. Polymorphonuclear leukocyte. E. Myofibroblast.

Description : Which of the following cell types are not crucial for healing a clean, incisional wound? A. Macrophage. B. Platelet. C. Fibroblast. D. Polymorphonuclear leukocyte. E. Myofibroblast.

Last Answer : Answer: DE DISCUSSION: Experimental studies have shown that healing may progress normally in the absence of polymorphonuclear leukocytes in an uninfected wound. In contrast, depletion of monocytes and ... wound contraction in open defects but have little if any role in clean, incisional wounds

The evaluation of a patient scheduled for elective surgery should always include the following as tests of hemostasis and coagulation: A. History and physical examination. B. Complete blood count (CBC), including platelet count. C. Prothrombin time (PT) and activated partial thromboplastin time (APTT). D. Studies of platelet aggregation with adenosine diphosphate (ADP) and epinephrine.

Description : The evaluation of a patient scheduled for elective surgery should always include the following as tests of hemostasis and coagulation: A. History and physical examination. B. Complete blood count ( ... (APTT). D. Studies of platelet aggregation with adenosine diphosphate (ADP) and epinephrine.

Last Answer : Answer: A DISCUSSION: The evaluation of most patients scheduled for elective surgery who do not have a history of significant bleeding disorders is somewhat controversial. An adequate history and ... suspected of having qualitative defects of platelet function (e.g., von Willebrand's disease)

Which of the following is/are true of the actions of transforming growth factor beta (TGF-b) during wound repair? A. Increased matrix and proteoglycan synthesis. B. Inhibition of proteases. C. Stimulation of plasminogen inhibitor. D. Chemotaxis for fibroblasts and macrophages. E. Autoinduction of TGF-b.

Description : Which of the following is/are true of the actions of transforming growth factor beta (TGF-b) during wound repair? A. Increased matrix and proteoglycan synthesis. B. Inhibition of proteases. ... of plasminogen inhibitor. D. Chemotaxis for fibroblasts and macrophages. E. Autoinduction of TGF-b.

Last Answer : Answer: ABDE DISCUSSION: Through autocrine and paracrine mechanisms TGF-b stimulates the deposition of collagen and other matrix components by fibroblasts, inhibits proteases, blocks plasminogen inhibitor, ... effects. The sustained production of TGF-b at the wound site leads to tissue fibrosis

Dipalmitoyl lecithin acts as (A) Platelet activating factor (B) Second messenger for hormones (C) Lung surfactant (D) Anti-ketogenic compound

Description : Dipalmitoyl lecithin acts as (A) Platelet activating factor (B) Second messenger for hormones (C) Lung surfactant (D) Anti-ketogenic compound

Last Answer : Answer : C

The following are true about chemicals involved in allergic reaction: a. thromboxane -leukocyte activation b. prostaglandin-2 - vasodilatation c. platelet-activating factor - leukocyte activation d. heparin - augments inactivation of prostaglandins

Description : The following are true about chemicals involved in allergic reaction: a. thromboxane -leukocyte activation b. prostaglandin-2 - vasodilatation c. platelet-activating factor - leukocyte activation d. heparin - augments inactivation of prostaglandins

Last Answer : prostaglandin-2 - vasodilatation

Extract of the following plant has platelet activating factor (PAF) antagonistic activity and is claimed to benefit cognitive disorders due to cerebral ischaemia: A. Ginkgo biloba B. Claviceps purpurea C. Amanita muscaria D. Artemisia annua (p. 440) 33.12 3 3 . 1 2 A Aim4aii

Description : Extract of the following plant has platelet activating factor (PAF) antagonistic activity and is claimed to benefit cognitive disorders due to cerebral ischaemia: A. Ginkgo biloba B. Claviceps purpurea C. Amanita muscaria D. Artemisia annua (p. 440) 33.12 3 3 . 1 2 A Aim4aii

Last Answer : A. Ginkgo biloba

The following class(es) of drugs are clinically beneficial in bronchial asthma: A. Histamine H1 receptor antagonists B. Platelet activating factor (PAF) antagonists C. Leukotriene ( cys LT1) receptor antagonists D. All of the above

Description : The following class(es) of drugs are clinically beneficial in bronchial asthma: A. Histamine H1 receptor antagonists B. Platelet activating factor (PAF) antagonists C. Leukotriene ( cys LT1) receptor antagonists D. All of the above

Last Answer : C. Leukotriene ( cys LT1) receptor antagonists

Prolonged airway hyperreactivity is characteristically caused by: A. Histamine B. Prostaglandin E2 C. Platelet activating factor D. Bradykinin

Description :  Prolonged airway hyperreactivity is characteristically caused by: A. Histamine B. Prostaglandin E2 C. Platelet activating factor D. Bradykinin

Last Answer : C. Platelet activating factor

Dysmenorrhoea is often associated with excess production of the following autacoid by the endometrium: A. Bradykinin B. Prostaglandin C. Platelet activating factor D. 5-Hydroxytryptamine

Description :  Dysmenorrhoea is often associated with excess production of the following autacoid by the endometrium: A. Bradykinin B. Prostaglandin C. Platelet activating factor D. 5-Hydroxytryptamine

Last Answer : B. Prostaglandin

Which of the following statement(s) is/are true concerning water movement across cell membranes? a. Water moves only actively through cell membrane transport proteins b. For most cells of the body, the transmembrane hydrostatic pressure is 0 c. Water distribution is determined entirely by solute distribution d. Specialized cells such as the glomerulus of the kidney actively transport water to maintain hydrostatic pressure

Description : Which of the following statement(s) is/are true concerning water movement across cell membranes? a. Water moves only actively through cell membrane transport proteins b. For most cells of ... cells such as the glomerulus of the kidney actively transport water to maintain hydrostatic pressure

Last Answer : Answer: b, c The energetics of water transport across cell membranes is simplified by the fact that water moves only passively due to gradients of hydrostatic pressure or water ... water is distributed at equilibrium. Water distribution is determined entirely by solute to solute distribution