NEET MDS Synopsis
Malnutrition
General Pathology
Malnutrition
A. Marasmus - calorie malnutrition
A child with marasmus suffers growth retardation and loss of muscle. The loss of muscle mass results from catabolism and depletion of the somatic protein compartment.
With such losses of muscle and subcutaneous fat, the extremities are emaciated; by comparison, the head appears too large for the body. Anemia and manifestations of multivitamin deficiencies are present, and there is evidence of immune deficiency, particularly of T cell-mediated immunity.
B. Kwashiorkor - protein malnutrition - importance of protein quality as well as quantity
Marked protein deprivation is associated with severe loss of the visceral protein compartment, and the resultant hypoalbuminemia gives rise to generalized, or dependent, edema.
The weight of children with severe kwashiorkor is typically 60% to 80% of normal.
However, the true loss of weight is masked by the increased fluid retention (edema).
Children with kwashiorkor have characteristic skin lesions, with alternating zones of hyperpigmentation, areas of desquamation, and hypopigmentation, giving a "flaky paint" appearance.
Hair changes include overall loss of color or alternating bands of pale and darker hair, straightening, line texture, and loss of firm attachment to the scalp.
An enlarged, fatty liver (resulting from reduced synthesis of carrier proteins) and a tendency to develop early apathy, listlessness, and loss of appetite.
The bone marrow in both kwashiorkor and marasmus may be hypoplastic, mainly because of decreased numbers of red cell precursors. How much of this derangement is due to a deficiency of protein and folates or to reduced synthesis of transferrin and ceruloplasmin is uncertain. Thus, anemia is usually present, most often hypochromic microcytic anemia, but a concurrent deficiency of folates may lead to a mixed microcytic-macrocytic anemia.
C. Most cases of severe malnutrition are a combination of A and B usually characterized by:
• Failure of growth
• Behavioral changes
• Edema (kwashiorkor)
• Dermatosis
• Changes in hair
• Loss of appetite
• Liver enlargement
• Anemia
• Osteoporosis
Impression Materials - Reaction
Dental Materials
Physical reaction-cooling causes reversible hardening
Chemical reaction-irreversible reaction during setting
Lines in Third Molar Assessment
Oral and Maxillofacial SurgeryLines in Third Molar Assessment
In the context of third molar (wisdom tooth) assessment and extraction,
several lines are used to evaluate the position and inclination of the tooth, as
well as the amount of bone that may need to be removed during extraction. These
lines provide valuable information for planning the surgical approach and
predicting the difficulty of the extraction.
1. White Line
Description: The white line is a visual marker that
runs over the occlusal surfaces of the first, second, and third molars.
Purpose: This line serves as an indicator of the axial
inclination of the third molar. By assessing the position of the
white line, clinicians can determine the orientation of the third molar in
relation to the adjacent teeth and the overall dental arch.
Clinical Relevance: The inclination of the third molar
can influence the complexity of the extraction procedure, as well as the
potential for complications.
2. Amber Line
Description: The amber line is drawn from the bone
distal to the third molar towards the interceptal bone between the first and
second molars.
Purpose: This line helps to delineate which parts of
the third molar are covered by bone and which parts are not. Specifically:
Above the Amber Line: Any part of the tooth above
this line is not covered by bone.
Below the Amber Line: Any part of the tooth below
this line is covered by bone.
Clinical Relevance: The amber line is particularly
useful in the Pell and Gregory classification, which
categorizes the position of the third molar based on its relationship to the
surrounding structures and the amount of bone covering it.
3. Red Line (George Winter's Third Line)
Description: The red line is a perpendicular line drawn
from the amber line to an imaginary line of application of an elevator. This
imaginary line is positioned at the cement-enamel junction (CEJ) on
the mesial aspect of the tooth, except in cases of disto-angular impaction,
where it is at the distal CEJ.
Purpose: The red line indicates the amount of bone that
must be removed before the elevation of the tooth can occur. It effectively
represents the depth of the tooth in the bone.
Clinical Relevance: The length of the red line
correlates with the difficulty of the extraction:
Longer Red Line: Indicates that more bone needs to
be removed, suggesting a more difficult extraction.
Shorter Red Line: Suggests that less bone removal
is necessary, indicating an easier extraction.
Glycogenolysis
Biochemistry
Glycogenolysis
Breakdown of glycogen to glucose is called glycogenolysis. The Breakdown of glycogen takes place in liver and muscle. In Liver , the end product of glycodgen breakdown is glucose where as in muscles the end product is Lactic acid Under the combined action of Phosphorylase (breaks only –α-(1,4) linkage )and Debranching enzymes (breaks only α-(1,6) linkage )glycogen is broken down to glucose.
FUNGAL INFECTION- Histoplasmosis
General Pathology
FUNGAL INFECTION
Histoplasmosis
A disease caused by Histoplasma capsulatum, causing primary pulmonary lesions and hematogenous dissemination.
Symptoms and Signs
The disease has three main forms. Acute primary histoplasmosis is usually asymptomatic
Progressive disseminated histoplasmosis follows hematogenous spread from the lungs that is not controlled by normal cell-mediated host defense mechanisms. Characteristically, generalized involvement of the reticuloendothelial system, with hepatosplenomegaly, lymphadenopathy, bone marrow involvement, and sometimes oral or GI ulcerations occurs, particularly in chronic cases
Progressive disseminated histoplasmosis is one of the defining opportunistic infections for AIDS.
Chronic cavitary histoplasmosis is characterized by pulmonary lesions that are often apical and resemble cavitary TB. The manifestations are worsening cough and dyspnea, progressing eventually to disabling respiratory dysfunction. Dissemination does not occur
Diagnosis
Culture of H. capsulatum from sputum, lymph nodes, bone marrow, liver biopsy, blood, urine, or oral ulcerations confirms the diagnosis
Adrenergic Agents
Pharmacology
ISOPRENALINE
It is beta-receptor stimulant, which stimulates the heart and causes tachycardia.
It relaxes the smooth muscles particularly the bronchial and GIT. It is mainly used in bronchial asthma, in the treatment of shock and as a cardiac stimulant in heart block.
ORCIPRENALINE
Is a potent β-adrenergic agonist.
Receptor sites in the bronchi and bronchioles are more sensitive to the drug than those in the heart and blood vessels.
AMPHETAMINE
increases the systolic and diastolic blood pressure. Amphetamine is a potent CNS stimulant and causes alertness, insomnia, increased concentration, euphoria or dysphoria and increased work capacity.
Amphetamines are drugs of abuse and can produce behavioural abnormalities and can precipitate psychosis.
PHENYLEPHRINE
It is used as a nasal decongestant and mydriatic agent and also in the treatment of paroxysmal supraventricular tachycardia.
UTERINE RELAXANTS (TOCOLYTICS)
ISOXSUPRINE
Isoxsuprine has a potent inhibitory effect on vascular and uterine smooth muscle and has been used in the treatment of dysmenorrhoea, threatened abortion, premature labour and peripheral vascular diseases.
Operator position
Pharmacology
Operator position
For the right-handed operator, the 8 and 10 o’clock position and for left-handed operators, the corresponding 2 and 4 o’clock position almost always allows for optimal visualization of the injection field.
TCI -Target Controlled Infusion
Pharmacology
TCI -Target Controlled Infusion
TCI is an infusion system which allows the anaesthetist to select the target blood concentration required for a particular effect and then to control depth of anaesthesia by adjusting the requested target concentration
Mechanism
Instead of setting ml/h or a dose rate (mg/kg/h), the pump can be programmed to target a required blood concentration.
• Effect site concentration targeting is now included for certain pharmacokinetic models.
• The pump will automatically calculate how much is needed as induction and maintenance to maintain that concentration.