Tag: HYT Quiz

Glucose-6 -phosphate dehydrogenase deficiency (G6PD)

Glucose-6 -phosphate dehydrogenase deficiency (G6PD)

Q. 1

Acute hemolytic anemia in G6PD deficiency is triggered by all, EXCEPT:

 A

Fava beans

 B

Infections

 C

Drugs

 D

Anemia

Q. 1

Acute hemolytic anemia in G6PD deficiency is triggered by all, EXCEPT:

 A

Fava beans

 B

Infections

 C

Drugs

 D

Anemia

Ans. D

Explanation:

Acute hemolytic anemia in G6PD deficiency is triggered by fava beans, infections, and drugs. The onset can be extremely abrupt especially with favism in children.

 

Ref: Harrison, 18th edition, Page 878.


Q. 2

The most serious complication of acute hemolytic anemia in G6PD deficiency is:

 A

Acute renal failure

 B

Congestive cardiac failure

 C

Cerebral infarction

 D

Acute liver failure

Q. 2

The most serious complication of acute hemolytic anemia in G6PD deficiency is:

 A

Acute renal failure

 B

Congestive cardiac failure

 C

Cerebral infarction

 D

Acute liver failure

Ans. A

Explanation:

The most serious threat from acute hemolytic anemia is the development of ARF. Ref: Harrison’s principles of internal medicine, 18th edition ; Page :879


Q. 3

All of the following are true regarding G6PD deficiency except:    

March 2010

 A

A recessive X-linked trait

 B

Females are commonly affected

 C

Oxidative stress causes hemolysis

 D

Protective against plasmodium falciparum malaria

Q. 3

All of the following are true regarding G6PD deficiency except:    

March 2010

 A

A recessive X-linked trait

 B

Females are commonly affected

 C

Oxidative stress causes hemolysis

 D

Protective against plasmodium falciparum malaria

Ans. B

Explanation:

Ans. B: Females are commonly affected

G6PD deficiency is a recessive X-linked trait, placing males at higher risk for symptomatic disease.

It is most common in Black patients or African descent (Class III). It has a protective effect against plasmodium falciparum malaria.

Pathophysiology

  • Glucose-6-phosphate dehydrogenase (G6PD)

– Catalyzes NADP to NADPH (pentose phosphate path)

– NADPH prevents oxidative damage to cells

– RBCs depend on G6PD for sole pathway to NADPH

– RBCs are most susceptible to insufficient G6PD

  • Oxidative stress results in acute Hemolytic Anemia
  • Drug-induced Hemolysis affects older cells -Younger cells have adequate enzyme levels to survive
  • G6PD mutations occur on distal long arm of C chromosome

Causes

  • Medications in G6PD Deficiency-Onset within 72 hours of intake

– Chloroquine and primaquine

– Sulfonamides

– Nitrofurantoins

  • Infection (most common cause)

– Salmonella

– Eschirichia coli

– Beta-hemolytic Streptococcus


Q. 4

With regards to G6PD deficiency, which of the following in false

 A

Affects the pentose phosphate pathway

 B

Associated with neonatal jaundice

 C

Acute haemolysis can be precipitated by broad beans

 D

X-linked recessive disorder that does not affect heterozygous famales

Q. 4

With regards to G6PD deficiency, which of the following in false

 A

Affects the pentose phosphate pathway

 B

Associated with neonatal jaundice

 C

Acute haemolysis can be precipitated by broad beans

 D

X-linked recessive disorder that does not affect heterozygous famales

Ans. D

Explanation:

Ans. is ‘d’ i.e., X-linked recessive disorder that does not affect heterozygous famales

  • Glucose 6-phosphate dehydrogenase (G6PD) deficiency, an X-linked disorder, is the most common enzymatic disorder of red blood cells in humans, affecting 400 million people worldwide.

Clinical spectrum

  • The clinical expression of G6PD variants encompasses a spectrum of hemolytic syndromes

The four forms of symptomatic G6PD deficiency :

  • Acute hemolytic anemia
  • Favism
  • Congenital nonspherocytic hemolytic anemia
  • Neonatal hyperbilirubinemia
  • G6PD deficiency is expressed in males carrying a variant gene that results in sufficient enzyme deficiency to lead to symptoms.

Acute hemolytic anemia

  • Almost all individuals with the most prevalent G6PD variants, G6PD A- and G6PD Mediterranean, are asymptomatic in the steady state.
  • They have neither anemia, evidence of increased red cell destruction, nor an alteration in blood morphology,. o However sudden destruction of enzyme deficient erythrocytes can be triggered by certain drugs or chemicals, by selected infections, and rarely by metabolic abnormalities (eg, diabetic ketoacidosis).

Clinical course

  • At two to four days after drug ingestion, there is the sudden onset of jaundice, pallor, and dark urine, with or without abdominal and back pain.
  • This is associated with an abrupt fall in the hemoglobin concentration of 3 to 4 g/dL, during which time the
  • peripheral blood smear reveals red cell fragments, microspherocytes, and eccentrocytes or “bite” cells.
  • The anemia induces an appropriate stimulation of erythropoiesis, characterized by an increase in reticulocytes that is apparent within five days and is maximal at 7 to 10 days after the onset of hemolysis.
  • Even with continued drug exposure, the acute hemolytic process ends after about one week, with ultimate reversal of the anemia.

Inciting events

  • Patients with class II or III variants develop intermittent hemolysis only after one or more of the following inciting events.
  • Infection
  • Oxidant drugs
  • Chemical agents (eg, moth balls, aniline dyes, henna compounds)
  • Diabetic ketoacidosis
  • Ingestion of fava beans

Drugs and chemicals

  • Primaquine, dapsone, and a number of other drugs can precipitate hemolysis in G6PD deficient subjects.

Foods: fava beans and bitter melon

  • G6PD deficiency can also be precipitated by the the ingestion of fresh fava beans (favism).
  • Manifestation offavism begins 5-24 hrs after fava bean ingestion and include headache, nausea, back pain.

Congenital nonspherocytic hemolytic anemia

  • Patients with class I G6PD variants have such severe G6PD deficiency that lifelong hemolysis occurs in the absence of infection or drug exposure.
  • Such patients fall under the category of having congenital nonspherocytic hemolytic anemia.
  • These G6PD variants have low in vitro activity and/or marked instability of the molecule, and most have DNA mutations at the glucose-6-phosphate or NADP binding sites.
  • These sites are central to the function of G6PD, which oxidizes glucose-6-phosphate and reduces NADP to NADPH. It is presumed that the functional defect is so severe that the red cells cannot withstand even the normal oxidative stresses encountered in the circulation.
  • Anemia and jaundice are often first noted in the newborn period, and the degree of hyperbilirubinemia is frequently of sufficient severity to require exchange transfusion.
  • After infancy, hemolytic manifestations are subtle and inconstant. Most individuals have mild to moderate anemia (hemoglobin 8 to 10 g/dL) with a reticulocyte count of 10 to 15 percent. Pallor is uncommon, scleral icterus is intermittent, splenomegaly is rare, and splenectomy generally is of little benefit.
  • Hemolysis can be exaggerated by exposure to drugs or chemicals with oxidant potential or exposure to fava beans.
  • Some drugs with relatively mild oxidant potential that are safe in patients with class II or class III G6PD variants may increase hemolysis in patients with class I variants.

Neonatal hyperbilirubineinia

  • The clinical picture of neonatal jaundice due to G6PD deficiency differs from neonatal jaundice seen in hemolytic disease of the fetus and newborn (HDFN) associated with Rh(D) incompatibility in two main respects.
  • G6PD deficiency-related neonatal jaundice is rarely present at birth; the peak incidence of clinical onset is between days two and three.
  • a There is more jaundice than anemia, and the anemia is rarely severe. The severity ofjaundice varies widely, from being subclinical to imposing the threat of kernicterus if not treated

Quiz In Between



Glucose-6 -phosphate dehydrogenase deficiency (G6PD)

Glucose-6 -phosphate dehydrogenase deficiency (G6PD)


GLUCOSE-6 –PHOSPHATE DEHYDROGENASE DIFICIENCY ANAEMIA (G6PD)

  • Hereditary disorders of red cell interior are of 2 types-

1. Red cell enzyme defects (enzymopathies)

  • Defective red cell metabolism involves 2 pathways-
  1. Defect in hexose monophosphate shunt- E.g. G6PD deficiency.
  2. Defect in Embden- Meyerhoff pathway- E.g. Pyruvate kinase deficiency

2. Disorders of haemoglobin (Haemoglobinopathies) 

G6PD-

  • G6PD gene is located on the X- chromosome & its deficiency.
  • Sex- linked trait affecting males and femal are carriers.
  • Normal G6PD variant- Type B & Type A+
  • Most common & significant variant A- type found in dark males.
  • A- type G6PD variant protects against malaria.
  • Abnormal protein folding leads to G6PD loss.
  • Haemolytic attacks due to oxidant stress-
  1. Drugs- antimalarial (Pyrimaquine), sulphonamides, vitamin K.
  2. Ingestion of Fava beans (favaism)
  3. Infections

Pathogenesis-

  • In G6PD deficient cells oxidant will denature globin of haemoglobin to form Heinz bodies.
  • To detect Heinz bodies stain, crystal violet is used.
  • Macrophage will remove Heinz bodies & bite cells are formed.

Clinical features-

  • Acute haemolytic anaemia
  • Acute renal failure
  • Neonatal jaundice

Lab findings-

1. During period of acute haemolysis,

  • Rapid fall in haematocrit value.
  • Formation of Heinz bodies is visualized by crystal violet called Heinz body haemolytic anaemia.

2. Between the crises- red cell survival is short.

 Diagnosis

  • MRT, Fluorescent screening test, ascorbate cyanotic screening test.
  • Direct enzyme assay in red cells.

Treatment-

  • Prevention of haemolytic anaemia
  • Blood transfusion rarely.

Exam Important

  • Hereditary disorders of red cell interior are of 2 types-
  1. Red cell enzyme defects (enzymopathies)
  • Defective red cell metabolism involves 2 pathways-

a) Defect in hexose monophosphate shunt- E.g. G6PD deficiency.

  • G6PD gene is located on the X- chromosome & its deficiency.
  • Sex- linked trait affecting males and femal are carriers.
  • A- type G6PD variant protects against malaria.
  • Abnormal protein folding leads to G6PD loss.
  • Haemolytic attacks due to oxidant stress-
  1. Drugs- antimalarial (Pyrimaquine), sulphonamides, vitamin K.
  2. Ingestion of Fava beans (favaism)
  3. Infections

Pathogenesis-

  • In G6PD deficient cells oxidant will denature globin of haemoglobin to form Heinz bodies.
  • To detect Heinz bodies stain, crystal violet is used.

Clinical features-

  • Acute haemolytic anaemia
  • Acute renal failure

Lab findings-

  1. During period of acute haemolysis,
  • Rapid fall in haematocrit value.
  • Formation of Heinz bodies is visualized by crystal violet called Heinz body haemolytic anaemia.
Don’t Forget to Solve all the previous Year Question asked on Glucose-6 -phosphate dehydrogenase deficiency (G6PD)

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Healing of specialised tissue (fracture healing)

Healing of specialised tissue (fracture healing)

Q. 1

Following a fracture of the humerus, an adult patient has a biopsy of the healing area. Which of the following types of bone will the biopsy most likely show?

 A

Cancellous

 B

Compact

 C

Spongy

 D

Woven

Q. 1

Following a fracture of the humerus, an adult patient has a biopsy of the healing area. Which of the following types of bone will the biopsy most likely show?

 A

Cancellous

 B

Compact

 C

Spongy

 D

Woven

Ans. D

Explanation:

Bone is formed by type I collagen fibers, ground substance, and hydroxyapatite crystals. . It can be parallel (trabecular bone and periosteum) or concentric (Haversian system). When bone is formed quickly, as in a healing fracture site, metabolic bone disease, or tumor, the collagen is randomly oriented and is called woven bone.
Compact bone is the dense calcified external part of the bone. It is lamellar bone.
Cancellous , spongy and trabecular bone are all synonymous terms for the thinner network of bone within the cortex. These are also lamellar bone.

Q. 2

Last step in fracture healing is:

 A

Haematoma

 B

Callus formation

 C

Remodeling

 D

Consolidation

Q. 2

Last step in fracture healing is:

 A

Haematoma

 B

Callus formation

 C

Remodeling

 D

Consolidation

Ans. C

Explanation:

C i.e. Remodeling


Q. 3

The time necessary for healing of fracture depends on the following factors:

 A

Age of the patient

 B

Location of the fracture

 C

Type of the fracture

 D

All of the above

Q. 3

The time necessary for healing of fracture depends on the following factors:

 A

Age of the patient

 B

Location of the fracture

 C

Type of the fracture

 D

All of the above

Ans. D

Explanation:

D i.e. All

Quiz In Between


Q. 4

The most important factor in fracture healing is:

 A

Good alignment

 B

Organization of blood clot

 C

Accurate reduction and 100% apposition of fractured fragments

 D

Immobilisation

Q. 4

The most important factor in fracture healing is:

 A

Good alignment

 B

Organization of blood clot

 C

Accurate reduction and 100% apposition of fractured fragments

 D

Immobilisation

Ans. D

Explanation:

D i.e. Immobilization


Q. 5

Healing of # of bone is affected by:

 A

Micromovement

 B

Muscle interposition

 C

Hypoxia

 D

All

Q. 5

Healing of # of bone is affected by:

 A

Micromovement

 B

Muscle interposition

 C

Hypoxia

 D

All

Ans. D

Explanation:

A i.e. Micromovement; B i.e. Muscle interposition; C i.e. Hypoxia


Q. 6

Delayed wound healing is seen in all except‑

 A

Malignancy

 B

Hypertension

 C

Diabetes

 D

Infection

Q. 6

Delayed wound healing is seen in all except‑

 A

Malignancy

 B

Hypertension

 C

Diabetes

 D

Infection

Ans. B

Explanation:

Ans. is ‘b’ i.e., Hypertension 


Q. 7

Callus formation is seen between what duration of fracture healing

 A

0 – 2 weeks

 B

2 – 4 weeks

 C

4 – 12 weeks

 D

12 – 16 weeks

Q. 7

Callus formation is seen between what duration of fracture healing

 A

0 – 2 weeks

 B

2 – 4 weeks

 C

4 – 12 weeks

 D

12 – 16 weeks

Ans. C

Explanation:

Ans. is ‘c’ i.e., 4 – 12 weeks

Healing of a fracture

The process of fracture healing varies according to the type of bone involved and the amount of movement at the fracture site. Following healing processes are there :‑

Indirect fracture healing (healing by callus)

This is the ‘natural’ form of healing in tubular bones and in the absence of rigid fixation when there is micromovement at fracture site. There is formation of internal and external callus. This stage is divided in three phases which are further subdivided into five stages :

Quiz In Between



Healing of specialised tissue (fracture healing)

Healing of specialised tissue (fracture healing)


HEALING IN SPECIALIZED TISSUES

Fracture healing-

  • Healing of fracture by callus formation depends on-
  1. Traumatic/ pathological
  2. Complete/ incomplete
  3. Simple/ compound 

Healing of any fracture takes place by-

  1. Primary union of fracture
  2.  Secondary union (more common)- it is described under 3 heading-

a) Procallus formation- it is as follows

  1. Hematoma formation
  2. Local inflammatory response- fragments of necrosed bone are scavenged by macrophages & osteoclasts
  3. Ingrowth of granulation tissue- soft tissue callus formed
  4. Callus composed of woven bone & cartilage

b) Osseous callus formation-

  • Callus formation takes place- 4 to 12 weeks

c) Remodelling

  • Osteoblast & osteoclast removes necrotic content, which results in remodelling of the united bone end into compact bone.

Exam Important

  • Healing of any fracture takes place by-
  1. Primary union of fracture
  2.  Secondary union (more common)- it is described under 3 heading-

a) Procallus formation- it is as follows

  1. Hematoma formation
  2. Local inflammatory response- fragments of necrosed bone are scavenged by macrophages & osteoclasts
  3. Ingrowth of granulation tissue- soft tissue callus formed
  4. Callus composed of woven bone & cartilage

b) Osseous callus formation-

  • Callus formation takes place- 4 to 12 weeks

c) Remodelling

  • Osteoblast & osteoclast removes necrotic content, which results in remodelling of the united bone end into compact bone.

 

Don’t Forget to Solve all the previous Year Question asked on Healing of specialised tissue (fracture healing)

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Stem cells

Stem cells

Q. 1

Stem cells are located in which region of hair follicle:

 A

Bulb

 B

Root

 C

Bulge

 D

Papilla

Q. 1

Stem cells are located in which region of hair follicle:

 A

Bulb

 B

Root

 C

Bulge

 D

Papilla

Ans. C

Explanation:

Bulge 

Stem cells are thought to reside mainly in the troughs of rete pegs, and in the outer root sheath bulge of the hair follicle

Stem Cell Niches

Stem cell

Organ

Niche

Epidermal stem cell

Hair follicle, Epidermis

Hair follicle bulge

Intestinal stem cell

Intestine

Base of colonic crypt above paneth cell

Oval cell (liver stem cell)

Liver

Canal of herring

Corneal stem cell

Cornea

Limbus

Neural stem cell

Brain

Olfactory bulb, Dentate gyrus of hippocampus

Satellite cells

Skeletal/Cardiac muscles

Beneath the myocyte basal lamina


Q. 2

Progenitor hematopoetic stem cells originate in’-

 A

Bone Marrow

 B

Thymus

 C

Lymph node

 D

Spleen

Q. 2

Progenitor hematopoetic stem cells originate in’-

 A

Bone Marrow

 B

Thymus

 C

Lymph node

 D

Spleen

Ans. A

Explanation:

Ans. is ‘a’ i.e., Bone marrow

  • Blood cells first appear during the third week of fetal embryonic development in the yolk sac, but these cells are generated from a primitive stem cell population restricted to the production of myeloid cells.

o Most studies suggest definitive hematopoietic stem cells arise in the mesoderm of the intraembryonic aorta/ gonad/mesonephros region, but evidence also exists for an origin within a small subset of yolk sac-derived cells.

  • By the third month of embryogenesis, stem cells derived from the AGM and/or yolk sac migrate to the liver, which is the chief site of blood cell formation until shortly before birth.
  • Beginning in the fourth month, stem cells migrate to the bone marrow to commence hematopoiesis at this site. o By birth, marrow throughout the skeleton is hematopoietically active and virtually the sole source of blood cells. o Up to the age of puberty, marrow throughout the skeleton remains red and hematopoietically active. o By age 18 only the vertebrae, ribs, sternum, skull, pelvis, and proximal epiphyseal regions of the humerus and femur retain red marrow, the remaining marrow becoming yellow, fatty, and inactive.

Q. 3

OVAL cells seen in stem cells of –

 A

Skin

 B

Cornea

 C

Liver

 D

Bone

Q. 3

OVAL cells seen in stem cells of –

 A

Skin

 B

Cornea

 C

Liver

 D

Bone

Ans. C

Explanation:

Ans. is ‘c’ i.e., Liver

o Stem cells are located in sites called niches. These include :

        Epidermal stem cells located in the bulge area of the hair follicle serve as a stem cells for the hair follicle and the epidermis.

        Intestinal stem cells are located at the base of a colon crypt, above Paneth cells.

        Liver stem cells (commonly known as OVAL cells) are located in the canals of Hering , structures that connect bile ductules with parenchymal hepatocytes.

        Corneal stem cells are located in the limbus region, between the conjunctiva and the cornea

        The bone marrow contains hematopoietic stem cells as well as stromal cells capable of differentiation into various lineages.

Quiz In Between


Q. 4

Stem cells are taken from all except –

 A

Liver

 B

Bone marrow

 C

Blood

 D

Adipose tissue

Q. 4

Stem cells are taken from all except –

 A

Liver

 B

Bone marrow

 C

Blood

 D

Adipose tissue

Ans. A

Explanation:

 

o There are three accessible sources of adult stem cells in humans :

  1. Bone marrow, which requires extraction by harvesting, that is, drilling into bone (typically the femur or iliac crest),
  2. Adipose tissue, which requires extraction by liposuction, and
  3. Blood, which requires extraction through pheresis, wherein blood is drawn from the donor (similar to a blood donation), passed through a machine that extracts the stem cells and returns other portions of the blood to the donor.
  4. Stem cells can also be taken from umbilical cord blood just after birth

Q. 5

When stem cells transforms to form cells characteristic of other tissues, the process is called as –

 A

De-differentiation

 B

Re-differentiation

 C

Trans-differentiation

 D

Sub-differentiation

Q. 5

When stem cells transforms to form cells characteristic of other tissues, the process is called as –

 A

De-differentiation

 B

Re-differentiation

 C

Trans-differentiation

 D

Sub-differentiation

Ans. C

Explanation:

Ans. is ‘c’ i.e., Trans-differentiation

Transdifferentiation

o Transdifferentiation takes place when a non-stem cell transform into a different type of cell, or when an already differentiated stem cell creates cells outside its already estabilished differentiation.

o Remember very important fact that it is the non-stem cell or already differentiated stem cell (i.e. mature cell) that is transformed into other type of cell. It is not stem cell that is transforming.

o Transdifferentiation is a type of metaplasia.

o Then, what is the difference between transdifferentiation and metaplasia.

         In Transdifferentiation only differentiated stem cell is transformed into other cell type, while in metaplasia any of the two, either stem cell or differentiated cell can transform into other cell type.

       So, all transdifferentiation processes are metaplasia, but not all metaplasia are transdifferentiation. o Most likely question has been wrongly framed here, there should be non-stem cell instead of stem cell in the question. Anyways answer remains the same, as no other option is related to this type of transformation.


Q. 6

Stem cells are located in which of the following location in the body?

 A

Retina

 B

Endometrium

 C

Intestine

 D

Choana

Q. 6

Stem cells are located in which of the following location in the body?

 A

Retina

 B

Endometrium

 C

Intestine

 D

Choana

Ans. C

Explanation:

Ans. is ‘c’ i.e., Intestine

Stem cells are located in sites called niches. These include :

Epidermal stem cells located in the bulge area of the hair follicle serve as a stem cells for the hair follicle and the epidermis.

Intestinal stem cells are located at the base of a colon crypt, above Paneth cells.

Liver stem cells (commonly known as OVAL cells) are located in the canals of Hering , structures that connect bile ductules with parenchymal hepatocytes.

Corneal stem cells are located in the limbus region, between the conjunctiva and the cornea

The bone marrow contains hematopoietic stem cells as well as stromal cells capable of differentiation into various lineages.


Q. 7

Stem cells are present where in cornea?

 A

Limbus

 B

Stroma

 C

Epithelium

 D

Descmet’s membrane

Q. 7

Stem cells are present where in cornea?

 A

Limbus

 B

Stroma

 C

Epithelium

 D

Descmet’s membrane

Ans. A

Explanation:

Limbal stem cells (also c/d corneal epithelial stem cells) are stem cells located in the basal epithelial layer of the corneal limbus.

Quiz In Between



Stem cells

Stem cells


STEM CELLS

  • Stem cells has major 2 properties-
  • Self renewal
  • Asymmetric replication (stochastic differentiation) 

Types of Stem cells-

1. Embryogenic stem cells (ES cells)-

  • They are pluripotent (generate all cell lineages)
  • Isolated from normal blastocysts
  • Most undifferentiated stem cells.

2. Adult stem cells

  • Also called as tissue stem cells.
  • Adult stem cells occur in specialized micro environmental within organ called stem cell niches.
  • Adult stem cells are-

a) Liver stem cells-

  • At canals of Hering
  • Forms bipotent progenitor called oval cells.

b) Skin stem cells-

  • Forms bulge stem cells.

c) intestinal crypt epithelium-

  • Located above Paneth cells.

d) Skeletal muscle

  • Located at basal lamina of myotubules.
  • Called as satellite cells.

e) Cornea

  • Located limbal stem cells.

f) Bone marrow

  • Pluripotent
  • Marrow stromal cells

g) Brain

  • Located at dentate gyrus
  • When stem cells transforms to form cells characteristic of other tissues, the process is called as trans differentiation.

Exam Important

Stem cells has major 2 properties-

  • Self renewal
  • Asymmetric replication (stochastic differentiation)

Embryogenic stem cells (ES cells)-

  • They are pluripotent (generate all cell lineages)

Adult stem cells

  • Also called as tissue stem cells.
  • Adult stem cells are-

a) Liver stem cells-

  • At canals of Hering
  • Forms bipotent progenitor called oval cells.

b) Skin stem cells-

  • Forms bulge stem cells.

c) intestinal crypt epithelium-

  • Located above Paneth cells.

d) Skeletal muscle

  • Located at basal lamina of myotubules.
  • Called as satellite cells.

e) Cornea

  • Located limbal stem cells.

f) Bone marrow

  • Pluripotent
  • Marrow stromal cells

g) Brain

  • Located at dentate gyrus
  • When stem cells transforms to form cells characteristic of other tissues, the process is called as trans differentiation.

 

Don’t Forget to Solve all the previous Year Question asked on Stem cells

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Urolithiasis

urolithiasis

Q. 1

Which one of the following gastrointestinal disorders predisposes to urolithiasis –

 A

Peutz – Jegher’s syndrome

 B

Short bowel syndrome

 C

Familial polyposis coli

 D

Ulcerative colitis

Q. 1

Which one of the following gastrointestinal disorders predisposes to urolithiasis –

 A

Peutz – Jegher’s syndrome

 B

Short bowel syndrome

 C

Familial polyposis coli

 D

Ulcerative colitis

Ans. B

Explanation:

Ans. is ‘b’ i.e., Short bowel syndrome 

Gallstones and kidney stones are known complications of IBD

Quiz In Between



Urolithiasis

urolithiasis


UROLITHIASIS

  • Urolithiasis/ nephrolithiasis is the formation of urinary calculi at any level of urinary tract.
  • Most common location of calculi arise in the kidney.
  • More common in males.
  • Seen in 2nd to 3rd decades of life.
  • They are characterised by colicky pain (renal colic) & hematuria.

Types of Urinary Calculi-

  • There are 4 types of urinary calculi-
  • 90% Idiopathic
  • Most common abnormality found in standard investigation – hypercalcemia
  • Calcium oxalate – most common (70%)
  • Struvite stones – 15%
  • Calcium phosphate – 10%

a) Calcium stones-

  • Most common of all calculi
  • Most common cause is hypercalciuria with or without hypercalcemia
  • They are radioopaque stones.

b) Mixed (Struvite) stones-

  • Made up of magnesium- ammonium- calcium phosphate so often called as struvite or triple phosphate stones.
  • Caused due to infection of urinary tract with organism as Proteus so called as infection induced stones.
  • ‘Staghorn stones’ is an example of struvite stone.

c) Uric acid stones-

  • Made of uric acid.
  • They are radiolucent.
  • Caused by hyperuricaemia and hyperuricosuria as primary and secondary gout.
  • Hyperuricosuria is the most important factor for the production ofuric acid stones.

 d) Cystine stones-

  • Formed in acidic urine due to genetic defect of metabolism.
  • They are yellowish and waxy.

Exam Important

  • Gastrointestinal disorders predisposes to urolithiasis -short bowel syndrome.
  • Gallstones and kidney stones are known complications of IBD
  • 90% Idiopathic
  • Most common abnormality found in standard investigation –hypercalcemia
  • Calcium oxalate – most common (70%)
  • Struvite stones – 15%
  • Calcium phosphate – 10%

 

Don’t Forget to Solve all the previous Year Question asked on urolithiasis

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Granulocyte Stimulating Factor (G-Csf)

Granulocyte Colony Stimulating Factor(G-CSF)

Q. 1

Drug of choice for Neutropenia due to cancer chemotherapy is

 A Vitamin B-12 
 B

IL 11

 C Filgrastim 
 D

Erythropoietin

Q. 1

Drug of choice for Neutropenia due to cancer chemotherapy is

 A Vitamin B-12 
 B

IL 11

 C Filgrastim 
 D

Erythropoietin

Ans. C

Explanation:

Filgrastim REF: KDT 6TH edition, page 833, internet resources

See APPENDIX 37 “ANTICANCER DRUGS TOXIC AMELIORATION”


Q. 2 Relative to filgrastim (G-CSF), sargramostim (GM-CSF)
 A Has greater  oral bioavailability
 B Is more  likely  to cause   thrombocytopenia 
 C Is more  likely  to elicit  an allergic reaction
 D Stimulates production of a wider  variety  of hematopoietic stem  cells
Q. 2 Relative to filgrastim (G-CSF), sargramostim (GM-CSF)
 A Has greater  oral bioavailability
 B Is more  likely  to cause   thrombocytopenia 
 C Is more  likely  to elicit  an allergic reaction
 D Stimulates production of a wider  variety  of hematopoietic stem  cells
Ans. D

Explanation:

Stimulates production of a wider variety of hematopoietic stem cells

GM-CSF  has  wider  biologic  activity  than  G-CSF; it stimulates  early myeloid stem cells in addition to cells destined become neutrophils.


Q. 3

Kostmann’s syndrome-treatment is

 A

Anti-thymocyte globulin + cyclosporin

 B

Anti-thymocyte globulin + cyclosporin + GM­CSF

 C

G-CSF

 D

GM-CSF

Q. 3

Kostmann’s syndrome-treatment is

 A

Anti-thymocyte globulin + cyclosporin

 B

Anti-thymocyte globulin + cyclosporin + GM­CSF

 C

G-CSF

 D

GM-CSF

Ans. C

Explanation:

G-CSF [Ref : Nelson Ighle p. 913]

  • Kostmann’s syndrome is an inherited disorder of the bone marrow.
  • It is also known as severe congenital neutropenia.
  • It is inherited in an autosomal recessive manner.
  • Congenital neutropenia is usually very severe and neutrophils are often completely absent in the blood of these patients at the time of diagnosis.
  • These patients usually show arrest of maturation of neutrophils at the promyelocyte stage.

– This means that their neutrophils rarely. fully mature into the cells that are capable of fighting infections. – As a result these patients usually suffer from severe infections ?

– Omphalitis (infection of the navel)

– Pneumonia

– Skin abscesses

– Otitis media during their first few years of life.

Pathogenesis

  • Kostmann’s syndrome or severe congenital neutropenia is believed to he caused by defect in a gene on chromosome (in p35-p34.3) that codes for granulocyte colony stimulating factor (GCSF).
  • This disease is believed to be caused due to defect in receptor in granulocyte colony stimulator factor.

– This receptor is located on granulocytes or neutrophils. The purpose of this receptor is the binding of the granulocyte to the cytokine (GCSF) in order to give signal to the cell to mature, to multiply, and enhance .function.

GCSF is a natural cytokine produced by the human body.

– Patients with congenital neutropenia also produce GCSF hut because of the defect in GCSF receptor the response of their neutrophils to the normal amounts of GCSF in the blood is reduced.

– These patients will respond to higher dose of GCSF (This is the basis of tit of disease).

  • In some patients the GCSF receptor develops changes that could also indicate progression towards leukemia. Treatment
  • Patients with congenital neutropenia respond to administration of GCSF.

– As soon as congenital neutropenia is diagnosed, patients should start treatment with GCSF. – This treatment usually stabilizes the neutrophil count of the patient.

– The response of these patients to GCSF treatment is different. There is a big variation in the dose of GCSF that different people receive.

– A small group of patient does not respond to even very high doses of GCSF.

  • In patients who do not respond to GCSF doses of 100 mcg/kg within fourteen days, a search for bone marrow donor should be started immediately and bone marrow transplantation should be performed as soon as matching donor is identified.


Quiz In Between


Q. 4 Drug of choice for Neutropenia due to cancer chemotherapy:
 A Vitamin B-12
 B IL 11
 C Filgrastim
 D Erythopoie tin
Q. 4 Drug of choice for Neutropenia due to cancer chemotherapy:
 A Vitamin B-12
 B IL 11
 C Filgrastim
 D Erythopoie tin
Ans. C

Explanation:

Filgrastim


Q. 5

Filgrastim is used in treatment of:

 A

Anemia

 B

Neutropenia

 C

Malaria

 D

Filarial

Q. 5

Filgrastim is used in treatment of:

 A

Anemia

 B

Neutropenia

 C

Malaria

 D

Filarial

Ans. B

Explanation:

Filgrastim is a recombinant human granulocyte colony stimulating factor (G-CSF) which is a 175 – aminoacid glyco-protein.

It differs from the natural granulocyte stimulating factor due to its lack in glycosylation and the presence of an extra N-terminal methionine. It has proved to be effective in the treatment of severe neutropenia.

Ref: Goodman and Gilman’s The Pharmacological Basis of Therapeutics, 11th Edition, Pages 1429-32; Immunopharmacology By Manzoor M. Khan, Pages 49-50


Q. 6

A child with recurrent severe bacterial infections is diagnosed of having Kostmann’s syndrome. Treatment is:

 A

Antithymocyte globulin + cyclosporine

 B

Antithymocyte globulin + cyclosporine – C31-CSF

 C

G-CSF

 D

GM-CSF

Q. 6

A child with recurrent severe bacterial infections is diagnosed of having Kostmann’s syndrome. Treatment is:

 A

Antithymocyte globulin + cyclosporine

 B

Antithymocyte globulin + cyclosporine – C31-CSF

 C

G-CSF

 D

GM-CSF

Ans. C

Explanation:

Kostmann syndrome is the severe neutropenia with maturation defect in the marrow progenitor cells.
Recombinant G-CSF will increase neutrophil counts in most patients and has the potential to prolong life expectancy.
Hematopoietic stem cell transplantation may be considered for patients with severe complications, especially those with severe congenital neutropenia.

 

 

 

Ref: Ambruso D.R., Hays T., Goldenberg N.A., Nuss R. (2012). Chapter 30. Hematologic Disorders. In W.W. Hay, Jr., M.J. Levin, R.R. Deterding, J.J. Ross, J.M. Sondheimer (Eds), CURRENT Diagnosis & Treatment: Pediatrics, 21e.

 

Quiz In Between


Q. 7

Filgrastim is used in the treatment of –

 A

Anemia

 B

Neutropenia

 C

Malaria

 D

Filaria

Q. 7

Filgrastim is used in the treatment of –

 A

Anemia

 B

Neutropenia

 C

Malaria

 D

Filaria

Ans. B

Explanation:

Ans. is ‘b’ i.e., Neutropenia

o Filgrastim is a recombinant human granulocyte colony stimulating factor (G-CSF) effective in the treatment of severe neutropenia.


Q. 8

Drug of choice for Neutropenia due to cancer chemotherapy is –

 A

Vitamin B-12

 B

IL 11

 C

Filgrastim

 D

Erythropoietin

Q. 8

Drug of choice for Neutropenia due to cancer chemotherapy is –

 A

Vitamin B-12

 B

IL 11

 C

Filgrastim

 D

Erythropoietin

Ans. C

Explanation:

Ans. is ‘c’ i.e., Filgrastin

o Filgrastim is a recombinant human granulocyte colony stimulating factor (G-CSF) effective in the treatment of severe neutropenia.


Q. 9

Kostmann’s syndrome-treatment is –

 A

Anti-thymocyte globulin + cyclosporin

 B

Anti- thy mocyte globulin + cyclosporin + GM-CSF

 C

G-CSF

 D

GM-CSF

Q. 9

Kostmann’s syndrome-treatment is –

 A

Anti-thymocyte globulin + cyclosporin

 B

Anti- thy mocyte globulin + cyclosporin + GM-CSF

 C

G-CSF

 D

GM-CSF

Ans. C

Explanation:

Ans. is ‘c’ i.e., G-CSF

Kostmann’s syndrome (severe congenital neutropenia)

  • Kostmann’s syndrome,an autosomal recessive disorder, is an inherited disorder of the bone marrow in which there is arrest of maturation of neutrophils at promyelocyte stage.

o There is congenital neutropenia and neutrophils are often completely absent in the blood at time of diagnosis. o Because of neutropenia, these patients suffer from severe infections e.g., omphalitis (infection of navel), Pneumonia, Skin abscesses, otitis media.

o Kostmann’s syndrome is believed to be caused due to defect in receptor of granulocyte colony stimulating factor (GCSF) on neutrophils (granulocytes). The purpose of this receptor is binding of the granulocyte to the cytokine (GCSF) in order to give signal to the cell to mature and multiply.

Patients with Kostamann’s syndrome produce GCSF but because of the defet in GCSF receptor the response of neutrophils to normal amounts of GCSF in the blood is reduced. However, they can respond if the amount of GCSF is increased –> These patients will respond to higher dose of GCSE

Quiz In Between



Granulocyte Stimulating Factor (G-Csf)

GRANULOCYTE STIMULATING FACTOR (G-CSF)


GRANULOCYTE COLONY-STIMULATING FACTOR

  • Granulocyte-colony stimulating factor (G-CSF or GCSF)/Colony-Stimulating Factor-3 (CSF 3).
    • A glycoprotein that stimulates bone marrow to produce granulocytes and stem cells.
  • Produced by endothelium, macrophages, and other immune cells in response to cytokines.
  • Recombinant G-CSFs include filgrastim, lenograstim, nartograstim & pegfilgrastim.
  • Normally present during pregnancy. 

Actions of G-CSF:

  • White blood cells
    • G-CSF-receptor present on precursor cells of bone marrow.
    • Initiates proliferation & differentiation into mature granulocytes
    • Stimulates survival, proliferation, differentiation and function of neutrophil precursors & mature neutrophils.
  • Hematopoietic system
    • Potent inducer of hematopoietic stem cell mobilization from bone marrow into bloodstream.
  • Neurons
    • Can also act on neuronal cells as neurotrophic factor.

Medical use:

  • Treatment of chemotherapy-induced neutropenia.
    • Also indicated for Kostmann’s syndrome (severe congenital neutropenia).
  • Used before blood donation.
    • Used to increase hematopoietic stem cells quantity in donor blood, before collection by leukapheresis.
    • This is particularly useful during hematopoietic stem cell transplantation.
  • During stem cell transplants
    • Given to receiver during hematopoietic stem cell transplantation, to compensate for conditioning regimens.
  • Fastens wound healing:
    • Systemic injection of G-CSF mobilizes hematopoietic stem cells to wound site and accelerate healing by clearing granulating bed.
  • Acts as reliable biomarker for Early-Late Onset Neonatal Sepsis (EOS).

Exam Important

  • Drug of choice for Neutropenia due to cancer chemotherapy is Filgrastim.
  • G-CSF stimulates production of a wider variety of hematopoietic stem cells.
  • Filgrastim is used in treatment of Neutropenia.
  • Treatment in a child with recurrent severe bacterial infections and diagnosed of having Kostmann’s syndrome is G-CSF.
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