Cellular Adaptation of Growth and Differentiation Petronini Flashcards
Hyperplasia, hypertrophy, atrophy and metaplasia are _________ adaptations, unlike
dysplasia
reversible
_________ is an increase in the volume of an organ induced by an increase in the number of
cells that compose that organ.
Hyperplasia
___________is an increase in the volume of an organ as a result of an increasing of the volume of
the cells.
Hypertrophy
what is neoplasm?
A neoplasm is an abnormal growth of cells in the body that can be benign, precancerous, or malignan
_________________ is a characteristic of tissues composed of permanent cells; some organs increase the
volume by hyperplasia and by hypertrophy, an example is the liver.
Hypertrophy
Cells can be divided into ____________________
labile cells (constantly divide), stable (divide when needed), and permanent cells (dont divide).
________ is typical of
tissues composed of labile cells; also stable cells can participate to hyperplasia.
Hyperplasia
which cytokines are important in liver compensatory hyperplasia?
Tumours Necrosis Factor-alpha (TNF
alpha) and IL-6, which are pro-inflammatory cytokine
what is an example of compensatory hyperplasia?
Liver regeneration
what are the types of hyperplasia?
Pathological, physiological, compensatory
what is an example of physiological hyperplasia?
proliferation of glandular epithelium of breast during puberty or pregnancy
which growth factors are important in liver compensatory hyperplasia?
HGF and
TGF alpha.
TGF alpha binds to another receptor called
Epidermal Growth Factor Receptor (EGFR).
Hepatocytes Growth Factor (HGF) induces
cell proliferation after binding the receptor
called Met.
HGF is also called scatter factor because it is
involved not only in the liver but also in other
aspect related to mobility.
What is c-myc?
C-myc is a Transcriptional Factor which binds to the DNA, more exactly it binds in
the promoter or enhances region of genes that codifies for proteins involved in the transition G0 or
G1 to S
Hyperplasia of the intestinal villi due to:
Lactation, pregnancy, diabetes
Hypoplasia of the intestinal villi due to:
prolonged fasting
Hyperplasia at the ___________ level is due to testosterone or androgenic stimulation.
prostatic
We have _______________ when there is an excessive hormonal stimulation: when there is an imbalance between estrogens and progesterone (or progestin in
general)
pathological hyperplasia
______________ is a chronic inflammatory dermatosis that affects 1-2% of the population; it’s a
multifactorial disease and it’s due to a defect in the control of cells proliferation and in the control of
cells differentiation.
Psoriasis
Psoriasis is considered an auto-immune disease.
Also stress affects this disease because stress affects our immune system.
During Psoriasis the proliferative activity of the basal layer is increased by ___ times (defect in cell
proliferation).
The differentiation process is not complete and the transition - instead of ____ weeks - lasts __days
10, 2-4, 4
Hypertrophy can be ?
Physiological and pathological
Why do cells get bigger during hypertrophy?
There is more protein synthesized
what does Atrial Natriuretic Factor
(ANF) induce?
induces the
kidneys to release more
water, so the volume of
blood is reduced and also
blood pressure values are
reduced
can you find cells with more than 2 sets of chromosomes in the liver and the heart?
yes, they increase the volume of the cells by
increasing the number of chromosomes. These cells are unable to divide but they are able to
duplicate the DNA.
Hypotrophy can be?
Physiological (embryonic and fetal development) and Pathological (reduction of the workload)
what is atrophy (hypotrophy)?
it is the reduction of the size of an organ or tissue by the decrease in the number and size of cells resulting in the loss of cell material
what are the causes of pathological hypotrophy?
- Reduced workload: if you sleep all day you have an atrophy.
- enervation
- when there is a reduction in blood flow
- when there is a compression
- when there is inadequate nutrition: for example in a clinical situation called cachexia,
typical of anorexia, cancer, AIDS, chronic diseases. - loss of endocrine stimulation
- with aging age induces an atrophy of the frontal lobe.
what is metaplasia?
Metaplasia is a reversible alteration in which a differentiated tissue of a certain type is replaced by
a differentiated tissue of a different kind but of the same histogenetic origin.
Metaplasia, in adults, occurs only within the tissues of ________________
epithelial and mesenchymal origin
In metaplasia a certain type of cell (cell A) is replaced by another type of cell (cell B); we have
three possibilities:
- cell A changes in cell B: the probability of this transition is very low.
- cell A is eliminated and its progenitors produce cell B: this is true.
- the new cell type is the result of a reprogramming of undifferentiated stem or
mesenchymal cells.
Epithelial metaplasia can be _________or _________ metaplasia.
flat, scaly
what are initiating factors?
they induce the DNA mutation
what are promoting factors?
It is hormones that can stimulate the proliferation of initiated cells
Which Vitamin is important in the differentiation of epithelial cells?
Vitamin A
what is in situ carsinoma?
a tumour that does not invade the connective tissue, it’s localised in the
epithelium and the basal membrane is not destruct. Last stage is invasive metastatic carcinoma
_______________ is when you have formation of cartilage, bone and adipose tissue, which
replace non-mesenchymal cells.
Mesenchymal metaplasia
what is dysplasia?
Dysplasia means “disorder growth”: dysplasia is an alteration of cell proliferation and cell differentiation. It is often observed in scaly (squamous) epithelia. It is an irreversible process
In dysplasia we can have:
- Loss of uniformity of individual cells;
- Loss of their architectural orientation;
- Remarkable polymorphism, hyperchromatic nuclei, and mitosis is more frequent and localized
also at the superficial level. Differentiation is also affected.
what is the biggest risk factor for the Cervical cancer?
HPV (human pappiloma virus)
What is anaplasia?
is a condition of cells with poor cellular differentiation, losing the morphological characteristics of mature cells and their orientation with respect to each other and to endothelial cells.
what is Pleiomorphism?
is the presence of cells different in size and shape large and hyperchromatic
nuclei; those nuclei contain a characteristic quantity of DNA higher than normal which is
aneuploidy (a content of DNA not multiple of 2n).
