MDS PREP
The principal chemical mediator of immediate phase, of acute inflammation is:
1. Serotonin
2. Histamine
3. Kinin-Kallikrein
4. Complement system
Pathology
Answer: 2
The principal chemical mediator of the immediate phase of acute inflammation
is Histamine. Here's a detailed explanation of the options given:
1. Serotonin: While serotonin is a vasoactive substance that can cause blood
vessels to constrict or dilate, it is not the primary mediator of the immediate
phase of acute inflammation. It is mainly associated with the regulation of
mood, appetite, and sleep. In the context of inflammation, it plays a minor role
compared to histamine.
2. Histamine: Histamine is indeed the correct answer. It is a potent chemical
mediator released from mast cells and basophils in response to injury or
antigenic stimulation. Upon release, histamine acts on blood vessels to cause
vasodilation, increased permeability, and increased blood flow to the injured
area, which are hallmark features of the immediate phase of acute inflammation.
This results in the cardinal signs of inflammation: redness (rubor), heat
(calor), swelling (tumor), and pain (dolor).
3. Kinin-Kallikrein system: The kinin-kallikrein system is another important
mediator of inflammation, but it is more involved in the later phases. When
activated, it results in the formation of kinins, such as bradykinin, which
contribute to increased vascular permeability and pain. However, it is not the
first line mediator in the immediate phase.
4. Complement system: The complement system is a group of proteins in the blood
that work with antibodies to destroy pathogens and trigger inflammation. It is a
key component of the innate immune response, but its activation and role are
more pronounced in the later stages of inflammation rather than the immediate
phase. The complement system is involved in the opsonization of pathogens,
recruitment of phagocytes, and the formation of the membrane attack complex,
which can lyse certain bacteria and cells.
The immediate phase of acute inflammation is characterized by the rapid response
to tissue injury, which includes vasoactive changes and increased vascular
permeability to allow fluid, cells, and proteins to move into the interstitial
space. Histamine is quickly released from mast cells and basophils and acts on
H1 receptors of blood vessels to induce vasodilation and increased permeability.
This leads to the early symptoms of inflammation, such as swelling, redness,
heat, and pain, and is crucial for the initiation of the inflammatory response
to protect the body from harm.
Palatal petechiae t are present in
1. hyperthyroidism
2. infectious mononucleosis
3. osteopetrosis
4. hypophosphatasia
Oral Pathology
Answer: 2
Palatal petechiae are often seen in infectious mononucleosis, which is caused by the Epstein-Barr virus.
Penetration power of X-ray is measure of
1. Exposure time
2. Milliamperage
3. Kilovoltage
4. None of the above
Oral Pathology
Answer: 3
Penetration power of X-ray is primarily measured by kilovoltage.
Leukaemia should be high on a list of differential diagnosis when which of the following is noted?
1. Spontaneous bleeding
2. Persistent headache
3. Epigastric pain
4. Chronic or acute arthralgia
Oral Pathology
Answer: 1
Spontaneous bleeding is a key indicator for considering leukemia in differential diagnosis.
The first vascular reaction In Inflammation is:
1. Vasoconstriction
2.
Vasodilation
3. Increased vascular permeability
4. Marginisation or pavementing
Pathology Answer: 2
The first vascular reaction in inflammation is Vasodilation.
Explanation:
Inflammation is the body's protective response to tissue injury or infection. It
is characterized by the classical signs of redness (rubor), heat (calor),
swelling (tumor), pain (dolor), and loss of function (functio laesa). The
initial vascular changes in the inflammatory process include:
1. Vasoconstriction: This is a temporary response that occurs immediately after
injury to minimize blood loss. However, it is quickly followed by the more
significant and prolonged phase of vasodilation.
2. Vasodilation: This is the first major vascular reaction in the inflammatory
response. Vasodilation occurs due to the release of substances such as
histamine, bradykinins, and prostaglandins from the damaged tissue cells and
mast cells. These substances are known as vasodilators and they cause the smooth
muscles surrounding the blood vessels to relax, leading to an increase in the
diameter of the blood vessels. This results in increased blood flow to the
injured area, which is essential for delivering white blood cells, nutrients,
and oxygen to the site of inflammation. The increased blood flow is what causes
the characteristic redness and heat of an inflamed area.
3. Increased vascular permeability: Although it is not the first vascular
reaction, increased vascular permeability is a critical component of the
inflammatory process. After vasodilation, the endothelial cells that line the
blood vessels become more permeable, allowing plasma and proteins to leak out of
the vessels into the surrounding tissue. This leads to the formation of an
exudate, which is the accumulation of fluid and proteins that makes up the
swelling (edema) seen in inflammation.
4. Marginisation or Pavementing: This is the process where neutrophils (a type
of white blood cell) move along the walls of blood vessels towards the site of
inflammation. It occurs later in the inflammatory response after the initial
vasodilation and increased vascular permeability. These cells then migrate
through the vessel walls into the tissue to combat pathogens and debris.
Infectious mononucleosis has
1. Multiple draining sinuses
2. Ulcers which bruise easily
3. Palatal perforation
4. Alveolar bone loss
Oral Pathology
Answer: 2
Infectious mononucleosis is characterized by ulcers that bruise easily.
The minimum distance and angle between the X-ray source and operator should be at least
1. 6 feet, 45 degree
2. 6 feet, 135 degree
3. 9 feet, 90 degree
4. 9 feet, 120 degree
Oral Pathology
Answer: 2
The minimum distance should be 6 feet at a 135-degree angle for safety.
Which of the following is not a complication of therapeutic radiation
1. Mucositis
2. Xerostomia
3. Cervical caries
4. Paraesthesia of the tongue
Oral Pathology
Answer: 4
Paraesthesia of the tongue is not a complication of therapeutic radiation.