Which of the following interfere with normal collagen formation or cross-linking? A. Beta-aminopropionitrile. B. Iron chelators. C. Vitamin C depletion. D. Proline analogs (e.g., cis-hydroxyproline). E. D-Penicillamine.

Which of the following interfere with normal collagen formation or cross-linking? A.  Beta-aminopropionitrile. B.  Iron chelators. C.  Vitamin C depletion. D.  Proline analogs (e.g., cis-hydroxyproline). E.  D-Penicillamine.
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Answer: ABCDE  DISCUSSION: Intramolecular and intermolecular cross-links are crucial for collagen structural stability. Formation of cross-links can be inhibited by two pharmacologic agents: beta-aminopropionitrile inhibits the enzyme lysyl oxidase, and D-penicillamine binds to collagen substrate directly to prevent collagen cross-link formation. Iron is a cofactor for prolyl hydroxylase, which is important for collagen synthesis. In high enough concentration, proline analogs prevent collagen formation with minimal effects on noncollagenase protein synthesis
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Hemostasis and the cessation of bleeding require which of the following processes? A. Adherence of platelets to exposed subendothelial glycoproteins and collagen with subsequent aggregation of platelets and formation of a hemostatic plug. B. Interaction of tissue factor with factor VII circulating in the plasma. C. The production of thrombin via the coagulation cascade with conversion of fibrinogen to fibrin. D. Cross-linking of fibrin by factor XIII.

Description : Hemostasis and the cessation of bleeding require which of the following processes? A. Adherence of platelets to exposed subendothelial glycoproteins and collagen with subsequent aggregation of platelets and ... conversion of fibrinogen to fibrin. D. Cross-linking of fibrin by factor XIII.

Last Answer : Answer: ABCD DISCUSSION: Hemostasis requires the interaction of platelets with the exposed subendothelial structures at the site of injury followed by aggregation of more platelets in that area. ... form a stable clot that incorporates the platelet plug and fibrin thrombus into a stable clot

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

All the following statement about hydroxyproline are true except (A) There is no codon for hydroxyproline (B) It is present in large amounts in collagen (C) Free proline cannot be hydroxylated to hydroxyproline (D) Hydroxylation of proline residues is catalysed by a dioxygenase

Description : All the following statement about hydroxyproline are true except (A) There is no codon for hydroxyproline (B) It is present in large amounts in collagen (C) Free proline cannot be hydroxylated to hydroxyproline (D) Hydroxylation of proline residues is catalysed by a dioxygenase

Last Answer : Answer : D

Factors that decrease collagen synthesis include all of the following except: A. Protein depletion. B. Infection. C. Anemia. D. Advanced age. E. Hypoxia.

Description : Factors that decrease collagen synthesis include all of the following except: A. Protein depletion. B. Infection. C. Anemia. D. Advanced age. E. Hypoxia.

Last Answer : Answer: C DISCUSSION: Collagen synthesis, an integral part of wound healing, is affected by many local and systemic factors. Protein depletion impairs fibroplasia. Hypoproteinemia leads to diminution of ... more than any other factor, wound infection is associated with the risk of wound failure

The vitamin required for the formation of hydroxyproline (in collagen) is (A) Vitamin C (B) Vitamin A (C) Vitamin D (D) Vitamin E

Description : The vitamin required for the formation of hydroxyproline (in collagen) is (A) Vitamin C (B) Vitamin A (C) Vitamin D (D) Vitamin E

Last Answer : Answer : A

Wound contraction and ultimate contracture may be controlled by which of the following drugs? A. Colchicine. B. D-Penicillamine. C. Thiphenamil (Trocinate). D. Glucocorticoids. E. Ibuprofen (Motrin).

Description : Wound contraction and ultimate contracture may be controlled by which of the following drugs? A. Colchicine. B. D-Penicillamine. C. Thiphenamil (Trocinate). D. Glucocorticoids. E. Ibuprofen (Motrin).

Last Answer : Answer: AC DISCUSSION: Wound contraction is carried out by highly specialized cells called myofibroblasts, which, as their name implies, have histologic characteristics of fibroblasts ... under experimental conditions. Glucocorticoids and NSAIDs do not affect the wound contraction process

In contrast to adult wound healing with scar formation, which of the following are characteristic of scarless fetal skin repair? A. Matrix rich in hyaluronic acid. B. Increased inflammatory response. C. Increased production of TGF-b. D. No collagen deposition. E. Minimal angiogenesis.

Description : In contrast to adult wound healing with scar formation, which of the following are characteristic of scarless fetal skin repair? A. Matrix rich in hyaluronic acid. B. Increased inflammatory response. C. Increased production of TGF-b. D. No collagen deposition. E. Minimal angiogenesis.

Last Answer : Answer: AE DISCUSSION: The ability of a fetus to heal without scar formation depends on its gestational age at the time of injury and the size of the wound defect. In ... repair has possible clinical applications in the modulation of adult fibrotic diseases and abnormal scar-forming conditions

Which of the following is/are true? A. Because of its thickness, the tensile strength of a healing wound on the eyelid is much less than one on the thick skin of the back. B. By 2 days, the experimental burst strength of skin is minimal since collagen has been formed in the wound but has not yet cross-linked. C. Wound strength reaches a plateau by 3 weeks. D. Wounds rarely, if ever, regain the strength of intact tissues.

Description : Which of the following is/are true? A. Because of its thickness, the tensile strength of a healing wound on the eyelid is much less than one on the thick skin of the back. B. By 2 days, ... strength reaches a plateau by 3 weeks. D. Wounds rarely, if ever, regain the strength of intact tissues.

Last Answer : Answer: BD DISCUSSION: Tensile strength measures load per cross-section area at rupture, whereas burst strength measures load required to break a wound, regardless of dimension. Therefore, skin wounds have ... a slower rate for more than a year. Wounds do not regain the strength of normal tissue

Which of the following statement(s) is/are true concerning the remodeling phase of wound healing? a. Total collagen content increases steadily through this phase b. The normal adult ratio of collagen is approximately 4:1 of type I to type III collagen. c. Eventually a scar will achieve the strength of unwounded skin d. The proteoglycans are responsible for the ground substance of the extracellular matrix

Description : Which of the following statement(s) is/are true concerning the remodeling phase of wound healing? a. Total collagen content increases steadily through this phase b. The normal adult ratio ... unwounded skin d. The proteoglycans are responsible for the ground substance of the extracellular matrix

Last Answer : Answer: b, d The transition from the proliferative phase to the remodeling phase of wound healing is defined by reaching collagen equilibrium. Collagen accumulation within the wound becomes maximal by ... in strength for six months or more, eventually reaching 70% of the strength of unwounded skin

Which of the following is/are true concerning wound fibroblasts? A. Fibroblasts synthesize and secrete collagen molecules. B. Wound fibroblasts are derived from blood-borne precursor cells. C. Fibroblasts migrate to a wound along fibrin strands, which are used as a scaffold. D. Large amounts of fibrin or blood clot can act as a physical barrier to fibroblast penetration, which delays normal wound healing.

Description : Which of the following is/are true concerning wound fibroblasts? A. Fibroblasts synthesize and secrete collagen molecules. B. Wound fibroblasts are derived from blood-borne precursor cells. C. ... clot can act as a physical barrier to fibroblast penetration, which delays normal wound healing.

Last Answer : Answer: ACD DISCUSSION: Fibroblasts appear in the wound on about the third day of healing and begin to synthesize and secrete collagen molecules. Wound fibroblasts arrive from cells surrounding ... enzymes, and large amounts of fibrin and blood clot prevent fibroblasts from entering the wound

Which of the following is an adhesion glycoprotein? A. Fibronectin. B. Tenascin. C. Laminin. D. Hyaluronic acid. E. Collagen type IV.

Description : Which of the following is an adhesion glycoprotein? A. Fibronectin. B. Tenascin. C. Laminin. D. Hyaluronic acid. E. Collagen type IV.

Last Answer : Answer: ABC DISCUSSION: Cell adhesion glycoproteins such as fibronectin, vitronectin, laminin, and tenascin provide a railroad track to facilitate epithelial and mesenchymal cell migration over the wound ... , and collagen type IV is a protein that is a crucial component of basement membrane

Sulphur is made available to the body by the amino acids: (A) Cystine and methionine (B) Taurine and alanine (C) Proline and hydroxyproline (D) Arginine and lysine MINERAL METABOLISM 191

Description : Sulphur is made available to the body by the amino acids: (A) Cystine and methionine (B) Taurine and alanine (C) Proline and hydroxyproline (D) Arginine and lysine MINERAL METABOLISM 191

Last Answer : Answer : A

Covalent modification of an enzyme usually involves phosphorylation / dephosphorylation of (A) Serine residue (B) Proline residue (C) Hydroxylysine residue (D) Hydroxyproline residue

Description : Covalent modification of an enzyme usually involves phosphorylation / dephosphorylation of (A) Serine residue (B) Proline residue (C) Hydroxylysine residue (D) Hydroxyproline residue

Last Answer : Answer : A

Carnitine is synthesized from (A) Lysine and methionine (B) Glycine and arginine (C) Aspartate and glutamate (D) Proline and hydroxyproline

Description : Carnitine is synthesized from (A) Lysine and methionine (B) Glycine and arginine (C) Aspartate and glutamate (D) Proline and hydroxyproline

Last Answer : Answer : A

All of the following statements about proline are true except (A) It is an imino acid (B) It can be synthesized from glutamate (C) It can be catabolised to glutamate (D) Free proline can be hydroxylated to hydroxyproline

Description : All of the following statements about proline are true except (A) It is an imino acid (B) It can be synthesized from glutamate (C) It can be catabolised to glutamate (D) Free proline can be hydroxylated to hydroxyproline

Last Answer : Answer : D

The amino acid from which synthesis of the protein of hair keratin takes place is (A) Alanine (B) Methionine (C) Proline (D) Hydroxyproline

Description : The amino acid from which synthesis of the protein of hair keratin takes place is (A) Alanine (B) Methionine (C) Proline (D) Hydroxyproline

Last Answer : Answer : B

True statements concerning hypoadrenal shock include which of the following? A. Adrenocortical insufficiency may manifest itself as severe shock refractory to volume and pressor therapy. B. The presence of hyperglycemia and hypotension may suggest the diagnosis of shock due to adrenocortical insufficiency. C. Hydrocortisone does not interfere with the serum cortisol assay and should be given to hemodynamically unstable patients suspected of having hypoadrenal shock. D. The rapid adrenocorticotropic hormone (ACTH) stimulation test should be performed to help establish the diagnosis of acute adrenocortical insufficiency.

Description : True statements concerning hypoadrenal shock include which of the following? A. Adrenocortical insufficiency may manifest itself as severe shock refractory to volume and pressor therapy. B. ... test should be performed to help establish the diagnosis of acute adrenocortical insufficiency.

Last Answer : Answer: AD DISCUSSION: Shock due to acute adrenocortical insufficiency is relatively uncommon but must be considered when shock refractory to volume replacement and pressor therapy is present. ... and it is the corticosteroid of choice while the ACTH stimulation test is being performed

In 3rd generation dentin bonding agents, HEMA (Hydroxyethylmethacrylate) is 1. a hydrophilic monomer that wets the dentinal surface 2. a hydrophilic resin that forms a ”hybrid” layer by chemically reacting the intertubular dentin. 3. a hydrophilic monomer that alters collagen to promote cross linking of collagen to dentin. 4. a bifunctional molecule resin that copolymerizes to bis-GMA resins. a. 1,2 b. 1,4 c. 2,3 d. 1,3 e. 3,4

Description : In 3rd generation dentin bonding agents, HEMA (Hydroxyethylmethacrylate) is 1. a hydrophilic monomer that wets the dentinal surface 2. a hydrophilic resin that forms a hybrid layer by chemically reacting the intertubular dentin. 3. a hydrophilic ... a. 1,2 b. 1,4 c. 2,3 d. 1,3 e. 3,4

Last Answer : b. 1,4

Which of the following statements regarding fibroblasts and their function in wound healing are true? a. IL-1 has both inhibitory and promotional effects on fibroblast growth b. TNFa stimulates fibroblast collagen synthesis c. IL-1 and TNFa have opposite effects on the healing of bone d. In human clinical trials, EGF (epithelial growth factor) has been demonstrated to accelerate epidermal regeneration in cutaneous wounds

Description : Which of the following statements regarding fibroblasts and their function in wound healing are true? a. IL-1 has both inhibitory and promotional effects on fibroblast growth b. TNFa ... EGF (epithelial growth factor) has been demonstrated to accelerate epidermal regeneration in cutaneous wounds

Last Answer : Answer: a, d IL-1 appears to be important in the process of normal wound repair. IL-1 has been shown to stimulate skin fibroblast and keratinocyte growth, as well as ... that recombinant EGF enhances keratinocyte migration. EGF is also a potent chemoattractant for granulation tissue fibroblasts

Which of the following statements regarding transforming growth factor b (TGF-b) are true? a. TGF-b expression is autoregulated b. TGF-b enhances collagen synthesis c. TGF-b inhibits extracellular matrix production d. TGF-b may inhibit or promote cellular proliferation

Description : Which of the following statements regarding transforming growth factor b (TGF-b) are true? a. TGF-b expression is autoregulated b. TGF-b enhances collagen synthesis c. TGF-b inhibits extracellular matrix production d. TGF-b may inhibit or promote cellular proliferation

Last Answer : Answer: a, b, d TGF-b appears to be one of the key cytokines in control of tissue repair. TGF-b is strongly chemotactic for neutrophils, T cells, monocytes, and fibroblasts. ... TGF-b stimulates the proliferation of densely plated human marrow fibroblasts, but is inhibitory at high concentrations

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 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

Which of the following tissues contain significant collagen useful for placing sutures to allow the prolonged tension necessary to maintain tissue approximation? a. Dermis b. Intestinal submucosa c. Muscular fascia d. Blood vessel wall

Description : Which of the following tissues contain significant collagen useful for placing sutures to allow the prolonged tension necessary to maintain tissue approximation? a. Dermis b. Intestinal submucosa c. Muscular fascia d. Blood vessel wall

Last Answer : Answer: a, b, c, d It takes at least three weeks for collagen to undergo sufficient remodeling and cross linking to attain moderate strength. Since most skin sutures are removed at one to ... , Scarpa's fascia, and blood vessel wall represent a partial list of tissues with high collagen content

Which of the following statements about respiratory acidosis are true? A. Compensation occurs by a shift of chloride out of the red blood cells. B. Renal compensation occurs rapidly. C. Retention of bicarbonate and increased ammonia formation are normal compensatory mechanisms. D. Narcotic administration is an unusual cause of respiratory acidosis. E. The ratio of bicarbonate to carbonic acid is less than 20:1.

Description : Which of the following statements about respiratory acidosis are true? A. Compensation occurs by a shift of chloride out of the red blood cells. B. Renal compensation occurs rapidly. C. Retention of ... of respiratory acidosis. E. The ratio of bicarbonate to carbonic acid is less than 20:1.

Last Answer : Answer: CE DISCUSSION: Renal compensation for acute hypoventilation is relatively slow. Depression of the respiratory center by morphine can lead to respiratory acidosis. Renal retention of bicarbonate, ... into red cells combine to increase the ratio of bicarbonate to carbonic acid to 20:1

Which of the following factors have been demonstrated to promote wound healing in normal individuals? a. Vitamin A supplementation b. Vitamin C supplementation c. Vitamin E application to the wound d. Zinc supplementation e. None of the above

Description : Which of the following factors have been demonstrated to promote wound healing in normal individuals? a. Vitamin A supplementation b. Vitamin C supplementation c. Vitamin E application to the wound d. Zinc supplementation e. None of the above

Last Answer : Answer: e Several important systemic factors or conditions influence wound healing. Interestingly, there are no known systemic conditions that lead to enhanced or more rapid wound healing. ... support the concept that supranormal provision of these factors enhance wound healing in normal patients

Collagen and elastin have the following similarity: (A) Both are triple helices (B) Both have hydroxyproline residues (C) Both have hydrolysine residues (D) Both are glycoproteins

Description : Collagen and elastin have the following similarity: (A) Both are triple helices (B) Both have hydroxyproline residues (C) Both have hydrolysine residues (D) Both are glycoproteins

Last Answer : Answer : A

A protein rich in hydroxyproline is (A) Prolamin (B) Procollagen (C) Collagen (D) Proinsulin

Description : A protein rich in hydroxyproline is (A) Prolamin (B) Procollagen (C) Collagen (D) Proinsulin

Last Answer : Answer : C

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

Scar formation is part of the normal healing process following injury. Which of the following tissues has the ability to heal without scar formation? a. Liver b. Skin c. Bone d. Muscle

Description : Scar formation is part of the normal healing process following injury. Which of the following tissues has the ability to heal without scar formation? a. Liver b. Skin c. Bone d. Muscle

Last Answer : Answer: c Every tissue in the body undergoes reparative processes after injury. Bone has the unique ability to heal without scar and liver has the potential to regenerate parenchyma, the only organ ... scar (cirrhosis) as well. With these exceptions, all other mature human tissues heal with scar

Thiols are alcohol analogs in which the oxygen has been replaced by sulfur (e.g., CH3SH). Given the fact that the S–H bond is less polar than the O–H bond, which of the following statements comparing thiols and alcohols is correct? (a) Hydrogen bonding forces are weaker in thiols. (b) Hydrogen bonding forces are stronger in thiols. (c) Hydrogen bonding forces would be the same. (d) No comparison can be made without additional information

Description : Thiols are alcohol analogs in which the oxygen has been replaced by sulfur (e.g., CH3SH). Given the fact that the S-H bond is less polar than the O-H bond, which of the following ... (c) Hydrogen bonding forces would be the same. (d) No comparison can be made without additional information

Last Answer : Hydrogen bonding forces are weaker in thiols.

Which of the following statement(s) is/are true concerning the antibody response to an invading antigen? a. All antibodies are composed of one type of heavy and one type of light protein chain b. The carboxyl terminus of the heavy chain is the antigen binding site c. Antibody of the immunoglobulin G class is the initial antibody produced in response to an antigenic stimulus d. Immunoglobulins A, D, and E play an active role in the circulating humoral response

Description : Which of the following statement(s) is/are true concerning the antibody response to an invading antigen? a. All antibodies are composed of one type of heavy and one type of light protein chain b. ... stimulus d. Immunoglobulins A, D, and E play an active role in the circulating humoral response

Last Answer : Answer: a Humoral defenses consist of antibody (immunoglobulin; Ig) and complement. All Ig classes (IgM, IgG, IgA, IgE, IgD) and IgG subclasses are composed of one type (M, G, A, E, D ... exist in smaller amounts in the circulation and do not appear to play a major role as host defense components

What is the major determinant in an individual patient's risk for perioperative complications? A. The surgical procedure. B. The length of the surgical procedure. C. The anesthetic technique (e.g., general, regional). D. The length of anesthesia. E. All of the above.

Description : What is the major determinant in an individual patient's risk for perioperative complications? A. The surgical procedure. B. The length of the surgical procedure. C. The anesthetic technique (e.g., general, regional). D. The length of anesthesia. E. All of the above.

Last Answer : Answer: A DISCUSSION: The planned surgical procedure is the major determining factor in assessing an individual patient's risk for perioperative complications and in deciding which anesthetic technique will be ... than anyone else the extent of the operation and the length of time it will require

Which of the following statements about the presence of gallstones in diabetes patients is/are correct? A. Gallstones occur with the same frequency in diabetes patients as in the healthy population. B. The presence of gallstones, regardless of the presence of symptoms, is an indication for cholecystectomy in a diabetes patient. C. Diabetes patients with gallstones and chronic biliary pain should be managed nonoperatively with chemical dissolution and/or lithotripsy because of severe complicating medical conditions and a high operative risk. D. The presence of diabetes and gallstones places the patient at high risk for pancreatic cancer. E. Diabetes patients with symptomatic gallstones should have prompt elective cholecystectomy, to avoid the complications of acute cholecystitis and g

Description : Which of the following statements about the presence of gallstones in diabetes patients is/are correct? A. Gallstones occur with the same frequency in diabetes patients as in the ... have prompt elective cholecystectomy, to avoid the complications of acute cholecystitis and gallbladder necrosis.

Last Answer : Answer: E DISCUSSION: Gallstones have been found to be very prevalent in patients with type II (non-insulin-dependent) diabetes mellitus, perhaps related to the dyslipoproteinemia in ... added mortality associated with it. There is no causal relationship between diabetes and pancreatic cancer

Rank the following laboratory tests and procedures in terms of their relative value to a 65-year-old woman who is to undergo elective resection of a sigmoid cancer. A. Carcinoembryonic antigen (CEA). B. Blood urea nitrogen (BUN). C. Electrocardiogram (ECG). D. Hemoglobin concentration (Hgb). E. Serum creatinine (Cr). F. Arterial blood oxygen tension (PaO 2) on room air. G. Serum sodium concentration (Na+).

Description : Rank the following laboratory tests and procedures in terms of their relative value to a 65-year-old woman who is to undergo elective resection of a sigmoid cancer. A. Carcinoembryonic antigen (CEA). B. ... Arterial blood oxygen tension (PaO 2) on room air. G. Serum sodium concentration (Na+).

Last Answer : Answer: CDFEBAG DISCUSSION: The most important test by far is the electrocardiogram, with its capacity to indicate signs of occult heart disease. The second most important evaluation is the hemoglobin ... for resection of the colon is always normal and would be of least value among these tests

As thrombin generation proceeds, the body has natural anticoagulant systems opposing further thrombus formation. Natural anticoagulants include: a. Tissue plasminogen activator (TPA) b. Antithrombin III c. Activated protein C d. Heparin cofactor II

Description : As thrombin generation proceeds, the body has natural anticoagulant systems opposing further thrombus formation. Natural anticoagulants include: a. Tissue plasminogen activator (TPA) b. Antithrombin III c. Activated protein C d. Heparin cofactor II

Last Answer : Answer: b, c, d Just as thrombin generation is the key to coagulation, antithrombin III is the most central anticoagulant proteins. This glycoprotein binds to thrombin, preventing its removal of ... in the body. Therefore, TPA is part of the fibrinolytic system rather than a natural anticoagulant

Fibrinolytic therapy is based on activation of plasminogen, the inactive proteolytic enzyme of plasma that binds to fibrin during the formation of thrombosis. Activation of plasminogen to plasmin results in selective thrombolysis at the fibrin clot surface. Which of the following statement(s) is/are true concerning agents used in thrombolytic therapy? a. Streptokinase is a bacterial protein which is antigenic in humans, resulting in allergic reactions in up to l5% of cases b. Tissue plasminogen activator acts directly on plasmin without an intermediate drug–plasmin complex c. The half-life of urokinase, streptokinase, and TPA all exceed 30 minutes d. Streptokinase is significantly cheaper than urokinase or TPA

Description : Fibrinolytic therapy is based on activation of plasminogen, the inactive proteolytic enzyme of plasma that binds to fibrin during the formation of thrombosis. Activation of plasminogen to plasmin results ... TPA all exceed 30 minutes d. Streptokinase is significantly cheaper than urokinase or TPA

Last Answer : Answer: a, b, d Streptokinase is a bacterial protein produced by group C b-hemolytic streptococci. It is therefore antigenic in humans and can be associated with allergic reaction in ... one agent over the other. Streptokinase however, is markedly less expensive than either urokinase or TPA

Which of the following statement(s) is/are true concerning translation of the mRNA message to protein synthesis? a. An adaptor molecule, tRNA, recognizes specific nucleic acid bases and unites them with specific amino acids b. Covalent attachment of tRNA to amino acids is energy dependent c. The formation of a peptide bond between the growing peptide chain and the free amino acid occurs in the free cytoplasm d. Complete protein synthesis takes hours

Description : Which of the following statement(s) is/are true concerning translation of the mRNA message to protein synthesis? a. An adaptor molecule, tRNA, recognizes specific nucleic acid bases and unites them ... and the free amino acid occurs in the free cytoplasm d. Complete protein synthesis takes hours

Last Answer : Answer: a, b The synthesis of protein involves conversion from a four-letter nucleotide language to one of 20 chemically distinct amino acids. This process is referred to as ... translation and be moving down the mRNA molecules simultaneously, thus increasing the rate of protein synthesis

There are a number of hypercoaguable states which can be associated with arterial or venous thrombosis and embolic phenomenon. These include: a. Heparin-associated thrombocytopenia b. Antithrombin III deficiency c. Von Willebrand disease d. Vitamin C deficiency

Description : There are a number of hypercoaguable states which can be associated with arterial or venous thrombosis and embolic phenomenon. These include: a. Heparin-associated thrombocytopenia b. Antithrombin III deficiency c. Von Willebrand disease d. Vitamin C deficiency

Last Answer : Answer: a, b A number of hypercoaguable states are present. These include heparin-associated thrombocytopenia in which a heparin-dependent platelet antibody causes aggregation of ... soft tissue increasing vascular permeability and fragility resulting in the potential for bleeding disorders

The standard management oral anticoagulant therapy for chronic treatment of venous thromboembolism is with the drug warfarin. Which of the following statement(s) is/are true concerning the administration of warfarin? a. An important complication of warfarin therapy is skin necrosis in patients with protein C deficiency b. Warfarin interferes with vitamin K dependent clotting factors II, VII, IX, X c. For effective anticoagulation the prothrombin time (PT) should be kept at 2 control d. It is recommended that warfarin be continued for at least one year after initial episode of deep venous thrombosis

Description : The standard management oral anticoagulant therapy for chronic treatment of venous thromboembolism is with the drug warfarin. Which of the following statement(s) is/are true concerning the administration ... warfarin be continued for at least one year after initial episode of deep venous thrombosis

Last Answer : Answer: a, b Warfarin interferes with the vitamin K dependent clotting factors II, VII, IX and X, protein C, and protein S. An important complication of warfarin is skin ... the benefit from anticoagulant therapy and thus is the basis for discontinuing warfarin administration at this time

Which of the statements listed below about bleeding disorders is/are correct? A. Acquired bleeding disorders are more common than congenital defects. B. Deficiencies of vitamin K decrease production of factors II, VII, IX, and X, protein C, and protein S. C. Hypothermia below 32؛C rarely causes a bleeding disorder. D. Von Willebrand's disease is a very uncommon congenital bleeding disorder.

Description : Which of the statements listed below about bleeding disorders is/are correct? A. Acquired bleeding disorders are more common than congenital defects. B. Deficiencies of vitamin K decrease production ... disorder. D. Von Willebrand's disease is a very uncommon congenital bleeding disorder.

Last Answer : Answer: AB DISCUSSION: Acquired bleeding disorders are significantly more common than congenital bleeding defects. Vitamin K deficiency may be related to malnutrition or competitive inhibition ... a relatively common disorder of bleeding and is generally undetectable by routine screening methods

The transfusion of fresh frozen plasma (FFP) is indicated for which of the following reasons? A. Volume replacement. B. As a nutritional supplement. C. Specific coagulation factor deficiency with an abnormal prothrombin time (PT) and/or an abnormal activated partial thromboplastin time (APTT). D. For the correction of abnormal PT secondary to warfarin therapy, vitamin K deficiency, or liver disease.

Description : The transfusion of fresh frozen plasma (FFP) is indicated for which of the following reasons? A. Volume replacement. B. As a nutritional supplement. C. Specific coagulation factor deficiency ... the correction of abnormal PT secondary to warfarin therapy, vitamin K deficiency, or liver disease.

Last Answer : Answer: CD DISCUSSION: The use of FFP as a volume expander is not indicated. There are currently several preparations (both crystalloid and colloid) that are equally effective and do not carry the infectious and ... vitamin K-dependent factors II, VII, IX, and X, as well as protein C and protein S

Cell regulation can be thought of as the effector side of cell communication. Most commonly cell regulation occurs by means of extracellular chemical messengers. Which of the following statement(s) is/are true concerning these messengers? a. Paracrine regulation involves a messenger which is produced and acts systemically b. The extracellular signal or stimulus is received by a receptor on or in the target cell c. Neurocrine regulation depends on a physical connection between the neuron and the target cell d. Most hormones, local mediators, and neurotransmitters readily cross the cell plasma membrane

Description : Cell regulation can be thought of as the effector side of cell communication. Most commonly cell regulation occurs by means of extracellular chemical messengers. Which of the following statement(s ... d. Most hormones, local mediators, and neurotransmitters readily cross the cell plasma membrane

Last Answer : Answer: b, c Depending on how the extracellular messenger arrives, cell regulation can be classified as paracrine, endocrine, or neurocrine. In paracrine regulation, a chemical messenger ... , local mediators, and neurotransmitters are water-soluble and cannot readily cross the plasma membrane

An 18-year-old man shot once in the left chest has a blood pressure of 80/50 mm. Hg, a heart rate of 130 beats per minute, and distended neck veins. Immediate treatment might include: A. Administration of one liter of Ringer's lactate solution. B. Subxiphoid pericardiotomy. C. Needle decompression of the left chest in the second intercostal space. D. Emergency thoracotomy to cross-clamp the aorta.

Description : An 18-year-old man shot once in the left chest has a blood pressure of 80/50 mm. Hg, a heart rate of 130 beats per minute, and distended neck veins. Immediate treatment might include: A. ... of the left chest in the second intercostal space. D. Emergency thoracotomy to cross-clamp the aorta.

Last Answer : Answer: AC DISCUSSION: The finding of distended neck veins in conjunction with hypotension should suggest tension pneumothorax or pericardial tamponade. Absent ipsilateral breath sounds and a trachea ... injuries. There is no role for aortic cross-clamping in this scenario of cardiogenic shock

A diabetic develops a severe perineal infection with skin necrosis, subcutaneous crepitance, and drainage of a thin, watery, grayish and foul-smelling fluid. Management should consist of: a. Gram stain of the fluid, which will likely demonstrate multiple bacteria including predominantly gram-positive rods b. A CT scan is indicated in a stable patient to define the extent of the disease c. Broad spectrum antibiotics followed with prompt extensive debridement is indicated d. A safe guideline is to resect infected necrotic tissue so that a several centimeter margin of grossly normal, healthy tissue can be achieved e. A colostomy is of little benefit in this situation

Description : A diabetic develops a severe perineal infection with skin necrosis, subcutaneous crepitance, and drainage of a thin, watery, grayish and foul-smelling fluid. Management should consist of: a. Gram stain ... normal, healthy tissue can be achieved e. A colostomy is of little benefit in this situation

Last Answer : Answer: a, b, c, d The presence of severe perineal infection (referred to as Fournier gangrene when this process involves the perineum and scrotum in males) is associated with a ... often provides improved wound care and patient management, although it is not invariably a positive outcome

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

Which of the following statements about normal salt and water balance are true? A. The products of catabolism may be excreted by as little as 300 ml. of urine per day. B. The lungs represent the primary source of insensible water loss. C. The normal daily insensible water loss is 600 to 900 ml. D. Excessive cell catabolism causes significant loss of total body water. E. In normal humans, urine represents the greatest source of daily water loss.

Description : Which of the following statements about normal salt and water balance are true? A. The products of catabolism may be excreted by as little as 300 ml. of urine per day. B. The lungs represent ... of total body water. E. In normal humans, urine represents the greatest source of daily water loss.

Last Answer : Answer: CE DISCUSSION: The skin is the primary source of insensible water loss. Including losses from the lungs, this averages 600 to 900 ml. per day. Catabolism liberates water of solution. In ... still excrete a minimum of 500 to 800 ml. of urine per day to expel the products of catabolism

Which of the following statements are true of a patient with hyperglycemia and hyponatremia? A. The sodium concentration must be corrected by 5 mEq. per 100 mg. per 100 ml. elevation in blood glucose. B. With normal renal function, this patient is likely to be volume overloaded. C. Proper fluid therapy would be unlikely to include potassium administration. D. Insulin administration will increase the potassium content of cells. E. Early in treatment adequate urine output is a reliable measure of adequate volume resuscitation.

Description : Which of the following statements are true of a patient with hyperglycemia and hyponatremia? A. The sodium concentration must be corrected by 5 mEq. per 100 mg. per 100 ml. elevation in blood ... . E. Early in treatment adequate urine output is a reliable measure of adequate volume resuscitation.

Last Answer : Answer: D DISCUSSION: Each 100-mg. per 100 ml. elevation in blood glucose causes a fall in serum sodium concentration of approximately 2 mEq. per liter. Excess serum glucose ... correction of the patient's associated acidosis produce movement of potassium ions into the intracellular compartment

Cytokines which play an important role in the metabolic response to injury include: a. Tumor necrosis factor—a (TNF) b. Interleukin-1 (IL-1) c. Interleukin-6 (IL-6) d. Interferon-g

Description : Cytokines which play an important role in the metabolic response to injury include: a. Tumor necrosis factor—a (TNF) b. Interleukin-1 (IL-1) c. Interleukin-6 (IL-6) d. Interferon-g

Last Answer : Answer: a, b, c, d TNF or cachetin is considered the primary mediator of the systemic effects of endotoxin, producing anorexia, fever, tachypnea, and tachycardia at low doses and hypotension, ... infected sells. IFN-g has the ability to upregulate the number of TNF receptors on various cell types

Which of the following statement(s) is/are true concerning cell membrane receptors? a. The largest family of cell surface receptors are the G-protein-linked receptors b. Activities of the G-protein involve binding and hydrolysis of ATP c. The G protein receptor generates an intracellular messenger commonly through the use adenylate cyclase d. Tyrosine kinase receptors are considered G-protein-linked receptors

Description : Which of the following statement(s) is/are true concerning cell membrane receptors? a. The largest family of cell surface receptors are the G-protein-linked receptors b. Activities of the ... through the use adenylate cyclase d. Tyrosine kinase receptors are considered G-protein-linked receptors

Last Answer : Answer: a, c All water-soluble regulatory molecules bind to the cell surface receptor proteins. Binding of the appropriate ligand evokes an intracellular signal which usually regulates ... are adenylate cyclase, which converts ATP to cAMP, and the polyphosphoinositide-specific phospholipase C

Vitamin for the formation of collagen fibres, teeth, bone, R.B.C. is (a) Vit. K (b) Vit. D (c) Vit. A (d) Vit. C

Description : Vitamin for the formation of collagen fibres, teeth, bone, R.B.C. is (a) Vit. K (b) Vit. D (c) Vit. A (d) Vit. C

Last Answer : (d) Vit. C