Download histology

Ingegneria delle tecnologie
per la salute
Fondamenti di
anatomia e istologia
aa. 2016-17
Risultati test in itinere 8.11.2016
•210 iscritti – 27 assenti = 183 presenti
•25 non idonei (13.7%)
16
14
12
10
8
Serie1
6
4
2
0
1
5
9 13 17 21 25 29 33 37 41 45 49 53 57 61 65 69 73 77 81 85 89 93 97 101105109113117121125129133137141145149153157
Riproviamo….
Test in itinere 22.12.2016, ore 15.00.
Schema generale approccio all’anatomia degli organi:
•Nome
•Tipo di organo: (cavo/parenchimatoso; pari/dispari)
•Derivazione embriologica (endo-meso-ecto-dermico)
•Forma e dimensioni
•Posizione nel corpo
•Rapporti anatomici
•Vascolarizzazione
•Innervazione
•funzione
+ istologia
Sistema respiratorio
RESPIRATORY SYSTEM
• every human cell needs to run oxidative cellular
respiration (=oxidative phosphorylation, process where
energy is produced in the form of ATP) where oxygen is
a reactant and carbon dioxide is a waste product
• it is actually the accumulation of carbon dioxide that
primarily drives the need to breathe
• carbon dioxide is exhaled and oxygen is inhaled through
the RS, which includes:
1.muscles to move air into and out of the lungs,
2.passageways through which air moves, and
3.microscopic gas exchange surfaces covered by capillaries.
RESPIRATORY SYSTEM
Major RS function: to provide oxygen to
body tissues for cellular respiration, remove
the waste product carbon dioxide, and help
to maintain acid-base balance.
RS also used for non-vital functions: sensing
odors, speech production, and for straining,
such as during childbirth or coughing
Functionally, RS
divided in:
conducting zone =
organs and
structures not
directly involved in
gas exchange
respiratory zone =
where gas
exchange occurs
RESPIRATORY
SYSTEM
Conducting Zone
major functions:
 to provide a route for
incoming and outgoing air,
 remove debris and
pathogens from the
incoming air,
 warm and humidify the
incoming air.
other functions:
 epithelium of the nasal
passages is essential to
sensing odors,
 bronchial epithelium that
lines the lungs can
metabolize some airborne
carcinogens.
Nose
(+ its Adjacent Structures)
major entrance and exit for the RS through the nose, divided into 2 sections:
1. external nose = surface and skeletal structures  outward appearance +
numerous functions
 root = region located between the eyebrows
 bridge = part that connects the root to the
dorsum
 dorsum nasi = length of the nose
 apex = tip of the nose
 alae (singular = ala) = cartilaginous structure
on either side of the apex forming the nostrils
 naris (plural = nares), or nostril opening =
the “holes”
 philtrum = concave surface that connects the
apex of the nose to the upper lip
 nasal bone = one of a pair lying under the root
and bridge, articulating superiorly with frontal
bone and laterally with maxillary bones.
 septal cartilage = flexible hyaline cartilage
connected to the nasal bone, forming the
dorsum nasi.
 alar cartilage = apex of the nose surrounding
naris.
Nose
(+ its Adjacent Structures)
Nose
(+ its Adjacent Structures)
2. Nasal cavity = separated into left and right sections by the nasal septum
nasal septum = anteriorly by a portion of the septal cartilage and posteriorly by the
perpendicular plate of the ethmoid and the vomer
lateral walls = 3 bony projections, called the superior, middle, and inferior nasal conchae
(turbinate), inferior conchae are separate bones, whereas the superior and middle conchae
are portions of ethmoid.
floor = palate (hard palate at the anterior region composed of bone + soft palate at the
posterior portion consists of muscle tissue)
Nose
(+ its Adjacent Structures)
Vomeronasal organ (Jacobson’s)
Nose
(+ its Adjacent Structures)
paranasal sinuses = air-containing spaces lined with a mucosa in the bones that
form the walls of the nasal cavity, serving to warm and humidify incoming air,
producing mucus and lightening the weight of the skull, named for its associated
bone: frontal sinus, maxillary sinus, sphenoidal sinus, and ethmoidal sinus
Nose
(+ its Adjacent Structures)
histology
 Nares + ant. portion of nasal cavities lined with mucous membranes,
containing sebaceous glands and hair follicles, preventing passage of large
debris, such as dirt, through nasal cavity
 olfactory epithelium detecting odors deeper in the nasal cavity
 conchae, meatuses, and paranasal sinuses lined by respiratory epithelium
composed of pseudostratified ciliated columnar epithelium + goblet cells 
cilia of the respiratory epithelium help remove the mucus and debris with a
constant beating motion, sweeping materials towards the throat to be
swallowed
 serous and mucus-producing cells also secrete the lysozyme enzyme and
proteins called defensins, with antibacterial properties and immune cells that
patrol the connective tissue deep to the respiratory epithelium provide
additional protection
Nose
(+ its Adjacent Structures)
histology
Nose
(+ its Adjacent Structures)
histology
Nose
(+ its Adjacent Structures)
histology
Pharynx
= tube formed by skeletal muscle and lined by mucous
membrane that is continuous with that of the nasal
cavities, divided into 3 major regions:
1. Nasopharynx
2. Oropharynx
3. Laryngopharynx
Pharynx
Nasopharynx = flanked by the conchae, shows at the top the pharyngeal tonsil (= adenoid,
aggregate of lymphoid reticular tissue), down the uvula (= small bulbous, teardrop-shaped
structure located at the apex of the soft palate) and an opening of auditory (Eustachian)
tubes
Pharynx
Eustachian Tube
Pharynx
Eustachian Tube
Bartolomeo Eustachi meglio conosciuto
come Eustachio (San Severino
Marche, 1500-1510 – Fossombrone, 27
agosto 1574) è stato un anatomista italiano.
Redige e completa tutti i suoi scritti sulla
base di osservazioni ed esperimenti.
Inaugura quell'anatomia sottile, proemio a
quella microscopica. Teorizzò lo studio della
tuba auditiva destra, ricordata tutt'oggi
come la Tromba di Eustachio. Individuò
inoltre le valvole coronarie, precisò
ulteriormente la struttura di alcune ossa
craniche, inietta di acqua calda le arterie
renali, cercò di determinare la struttura
dei reni e dei denti. Descrisse per la prima
volta le ghiandole surrenali e fu il primo
scopritore della vena alba, ora dotto
toracico. Indaga con acutezza e logica
lungimiranza sui cadaveri per malattie varie.
Pharynx
Oropharynx = passageway for both air and food, bordered superiorly by the nasopharynx
and anteriorly by the oral cavity (fauces)  nasopharynx becomes oropharynx, epithelium
changes from pseudostratified ciliated columnar to stratified squamous epithelium, contains
2 distinct sets of tonsils, the palatine and lingual tonsils.
Pharynx
tonsils
Tonsils are collections
of lymphoid tissue facing into the
aerodigestive tract. The set of
lymphatic tissue known
as Waldeyer's tonsillar ring includes
the adenoid tonsil, two tubal
tonsils, two palatine tonsils, and
the lingual tonsil.
When used unqualified, the term
most commonly refers specifically
to the palatine tonsils, which are
masses of lymphatic material
situated at either side at the back
of the human throat. The palatine
tonsils and the nasopharyngeal
tonsil are lymphoepithelial tissues
located near
the oropharynx and nasopharynx (p
arts of the throat).
Pharynx
Laryngopharynx = inferior to the oropharynx and posterior to the larynx, anteriorly opens
into the larynx, whereas posteriorly, it enters the esophagus, stratified squamous epithelium
continues
Pharynx
Pharynx
Larynx
= cartilaginous structure inferior to
the
laryngopharynx
connecting
pharynx to the trachea, regulating
the volume of air that enters and
leaves the lungs and producing
speech, made of several pieces of
cartilage, 3 large cartilage pieces: a)
thyroid cartilage (anterior), largest
piece of cartilage that makes up the
larynx, consists of the laryngeal
prominence, or “Adam’s apple,” which
tends to be more prominent in males,
b) epiglottis (superior), c) cricoid
cartilage (inferior), thick cartilage
forms a ring, with a wide posterior
region and a thinner anterior region
3 smaller paired cartilages: a)
arytenoids,
b)
corniculates
c)
cuneiforms—attach to the epiglottis
and the vocal cords and muscle
thathelp move the vocal cords
Larynx
Larynx
Il pomo d'Adamo è l'espressione con cui si designa comunemente la sporgenza
della cartilagine tiroidea che circonda la laringe, che si osserva in alcuni
individui pùberi e adulti in genere di sesso maschile, sulla linea mediana del collo. Nel
linguaggio medico viene definito prominenza laringea. L'espressione trae origine da
un'immagine di origine popolare, secondo la quale un boccone del frutto mangiato
da Adamo gli sarebbe rimasto incastrato in gola.
Larynx
Larynx
Larynx
Epiglottis = very flexible
piece of elastic cartilage
attached to thyroid cartilage,
covering the trachea opening,
resting on the glottis.
Glottis = composed of: a)
vestibular folds or false vocal
cord = a pair of folded
sections
of
mucous
membrane, b) true vocal
cords = white, membranous
folds attached by muscle to
the thyroid and arytenoid
cartilages of the larynx on
their outer edges, and the
space between these folds
Inner edges of the true vocal cords are free,
allowing oscillation to produce sound.
act of swallowing causes pharynx and larynx to
lift upward, allowing pharynx to expand and
epiglottis of the larynx to swing downward,
closing the opening to the trachea. These
movements produce a larger area for food to
pass through, while preventing food and
beverages from entering the trachea.
Larynx
Larynx
Larynx
Larynx
histology
Continuous with
laryngopharynx, larynx’ superior
portion is lined by stratified
squamous epithelium,
transitioning into
pseudostratified ciliated
columnar epithelium that
contains goblet cells. Similar to
the nasal cavity and
nasopharynx, this specialized
epithelium produces mucus to
trap debris and pathogens as
they enter the trachea: cilia
beat mucus upward towards
laryngopharynx, where it can be
swallowed down (esophagus).
Larynx
histology
Trachea
= extending from larynx to lungs, formed by 16 to 20 stacked, C-shaped pieces
of hyaline cartilage that are connected by dense connective tissue (providing
structural support and preventing the trachea from collapsing) + fibroelastic
membrane (formed by trachealis muscle and elastic connective tissue together) a
flexible membrane that closes the posterior surface of the trachea, connecting
the C-shaped cartilages, allowing the trachea to stretch and expand slightly
during inhalation and exhalation.
lined with pseudostratified ciliated columnar epithelium
Trachea
histology
Trachea
Bronchial Tree
 Trachea branches into the right and left primary bronchi (still lined
by pseudostratified ciliated columnar epithelium containing mucusproducing goblet cells, with rings of cartilage, similar to those of
the trachea, supporting their structure and preventing their
collapse: enter the lungs at the hilum, a concave region where blood
vessels, lymphatic vessels, and nerves also enter lungs) at the carina
(= raised structure containing specialized nervous tissue inducing
violent coughing if foreign body is present).
 Bronchi continue to branch into bronchial tree (or respiratory tree
= collective term used for multiple-branched bronchi) providing
passageway for air to move into and out of each lung and trapping
debris and pathogens.
 Bronchiole (about 1 mm in ) branches from the tertiary bronchi
and further branch until terminal bronchioles (more than 1000 in
each lung) leading to the structures of gas exchange and their
muscular walls do not contain cartilage like those of bronchi. This
muscular wall can change the size of the tubing to increase or
decrease airflow through the tube.
Bronchial Tree
Bronchial Tree
histology
Bronchial Tree
histology
Bronchial Tree
histology
Bronchial Tree
histology
Respiratory Zone
= includes structures that are directly involved in gas exchange, beginning where the terminal
bronchioles join a respiratory bronchiole (smallest type of bronchiole), which then leads to
an alveolar duct, opening into a cluster of alveoli.
Respiratory Zone
histology
Respiratory Zone
histology
Alveoli
alveolar duct = tube of smooth muscle and connective tissue, which
opens into a cluster of alveoli.
alveolar sac = cluster of many individual alveoli
alveolus = one of the many small, grape-like sacs connected to the
alveolar ducts responsible for gas exchange, approximately 200 µm
 with elastic walls that allow the alveolus to stretch during air
intake, which greatly increases the surface area available for gas
exchange and connected to their neighbors by alveolar pores, which
help maintain equal air pressure throughout the alveoli and lung
Alveoli
histology
 alveolar wall = 3 cell types:
1. type I alveolar cell = squamous epithelial cell of the alveoli, which constitute up to 97 % of the
alveolar surface area, 25 nm thick, highly permeable to gases, attached to a thin elastic
basement membrane
2. type II alveolar cell = (club cells, Clara cells) interspersed among the type I cells and secretes
pulmonary surfactant, a substance composed of phospholipids and proteins reducing surface
tension of alveoli
3. alveolar macrophage = phagocytic cell of the immune system roaming around the alveolar wall
that removes debris and pathogens
 respiratory membrane =
extremely
thin
epithelium
borders
endothelial membrane of
capillaries,
0.5
mm
thick, allowing gases to
cross
by
simple
diffusion,
allowing
oxygen to be picked up
by
the
blood
for
transport and CO to be
released into the air of
the alveoli.
Club cells…
 Club cells previously called Clara cells, as first
described by Max Clara (1899–1966), in 1937. Clara
(active member of Nazi Party) used tissue taken
from executed victims of Third Reich for his
research, including that leading to discovery of
Clara cells [1].
 In May 2012, editorial boards of most of major
respiratory journals concluded that the continued
use of Clara's eponym would be equivalent to
honoring him, therefore introducing a name-change
policy, which went into effect beginning January 1,
2013 [2].
 The term "Clara" was to be used parenthetically
after "club cell" for a 2-year period, at which point
when "Clara cell" and "Clara cell secretory protein"
were conclusively replaced with "club cell" and
"club cell secretory protein", respectively [3].
1.
2.
3.
Winkelmann A. et al. (2010). "The Clara cell - a "Third Reich eponym"?". European Respiratory Journal 36 (4): 722–7.
Irwin RS et al. (2013). "Spread the word about the journal in 2013: from citation manipulation to invalidation of patient-reported outcomes
measures to renaming the Clara cell to new journal features". Chest 143: 1–5.
Akram KM et al. (2013). "Club cells inhibit alveolar epithelial wound repair via TRAIL-dependent apoptosis". Eur Respir J 41: 683–694.
Alveoli
histology
Alveoli
histology
Lungs
= houses structures of both the
conducting and respiratory zones,
their main function to perform the
exchange of respiratory gases across
a very large epithelial surface area—
about 70 square mts—that is highly
permeable to gases.
Gross Anatomy
= pyramid-shaped, paired organs connected to the trachea by the right and left bronchi
and enclosed by the pleurae, which are attached to the mediastinum; on inf surface, lungs
are bordered by the diaphragm (= flat, dome-shaped muscle located at the base of the
lungs and thoracic cavity); right lung is shorter and wider than left, and left lung occupies
a smaller volume than right; cardiac notch = indentation on the surface of the left lung
allowing space for the heart; apex of the lung is superior region, whereas base is
opposite region near the diaphragm, costal surface of lung borders ribs and mediastinal
surface faces midline; composed of smaller units = lobes (right lung 3 lobes: sup, middle,
and inf; left lung 2 lobes: sup and inf), separated by fissures. Bronchopulmonary segment
= division of a lobe, each receiving air from its own tertiary bronchus and supplied with
blood by its own artery. Pulmonary lobule = subdivision formed by bronchi branching into
bronchioles, separated by interlobular septum (=wall, composed connective tissue)
Lungs
Lungs
Lungs
Lungs
Blood Supply
Being major function of the lungs
performing blood supply containing
deoxygenated blood, traveling to the
lungs where red blood cells pick up o2
to be transported to tissues
throughout the body, pulmonary artery
arises from the pulmonary trunk
carrying deoxygenated arterial blood
to the alveoli and branching multiple
times as it follows the bronchi,
becoming progressively smaller in
diameter; one arteriole accompanied by
venule supply drain one pulmonary
lobule, becoming pulmonary capillary
network, as they near the alveoli,
consisting of tiny vessels with very thin
walls that lack smooth muscle fibers,
creating the respiratory membrane:
once blood is oxygenated, it drains
from the alveoli by way of multiple
pulmonary veins, which exit the lungs
through the hilum.
Lungs
Blood Supply
Bronchial artery
Lungs
Nervous Innervation
Dilation and constriction of the airway are achieved through
nervous control by the parasympathetic (
bronchoconstriction) and sympathetic (bronchodilation)
nervous systems: reflexes such as coughing, and the ability of
the lungs to regulate oxygen and carbon dioxide levels, also
result from this autonomic nervous system control. Sensory
nerve fibers arise from the vagus nerve, and from the second
to fifth thoracic ganglia. The pulmonary plexus is a region on
the lung root formed by the entrance of the nerves at the
hilum. The nerves then follow the bronchi in the lungs and
branch to innervate muscle fibers, glands, and blood vessels.
Pleura
Each lung is enclosed within a
cavity that is surrounded by
the pleura (plural = pleurae)
= serous membranes
surrounding lungs, separated
by the mediastinum. pleurae
consist of 2 layers: 1.
visceral pleura = layer that
is superficial to the lungs,
and extends into and lines
the lung fissures; 2. parietal
pleura = outer layer
connected to the thoracic
wall, the mediastinum, and
the diaphragm; visceral and
parietal pleurae connect to
each other at the hilum;
pleural cavity = space
between visceral and parietal
layers.
Pleura
Pleura
histology
The visceral pleural
surface is seen here at
high power, with a normal
mesothelial surface of low
cuboidal cells. There is a
thin layer of connective
tissue, below which are
peripheral alveolar
walls and alveoli. Between
the visceral pleura
covering the lung and the
parietal pleura on the
chest wall is a
potential pleural
space that is ordinarily
filled with only a few cc's
of serous fluid.
Mesoderm origin!
Diaphragm
= dome-shaped curved
upwards structure
of muscle and fibrous tissue
separating thorax from
abdomen, with peripheral
attachments to abdominal
and chest walls, from which
muscle fibres converge in
a central tendon (crest of
the dome); emerges from
many surrounding
structures: ant xifoid and
along costal margin, lat ribs
6-12, post vertebra at T12
(+ 2 appendages, the right
and left crus, descend and
insert at L1 & L2) with 2
lumbocostal arches,
medial and lateral, on either
side.
Diaphragm
primarily innervated by
phrenic nerves formed
from cervical nerves C3,
C4 and C5, while the
central portion of the
diaphragm sends sensory
afferents via the phrenic
nerve, the peripheral
portions
of
the
diaphragm send sensory
afferents
via
the
intercostal (T5-T11) and
subcostal nerves(T12).
Hiccup =
reflex causes a strong contraction of the diaphragm followed about
0.25 seconds later by closure of the vocal cords, which results in the classic "hic" sound
Evolutionary causes
1. Clearance of air from stomach
A recent explanation by Howes in 2012: hiccups may have evolved
along with other reflexes developed in mammals that allow them to
coordinate suckling milk and breathing. Hiccups are only found in
mammals, and are most common in infants, becoming rarer as mammals
age. This may suggest that they evolved to allow air trapped in the
stomach of suckling infants to escape, allowing more milk to be
ingested. The hypothesis suggests that the air bubble in the stomach
stimulates the sensory limb of the reflex at receptors in the
stomach, esophagus and along the diaphragm. This triggers the
hiccup, which creates suction in the chest, pulling air from the
stomach up and out through the mouth, effectively burping the
animal. This theory is supported by the strong tendency for infants
to get hiccups, the component of the reflex that suppresses
peristalsis in the esophagus, and the existence of hiccups only in milkdrinking mammals.
Howes, D. (2012). "Hiccups: A new explanation for the mysterious reflex". BioEssays. 34 (6): n/a. doi:10.1002/bies.201100194
hiccup
Evolutionary causes
2. Phylogenetic hypothesis
An international respiratory research group composed of members from Canada,
France and Japan proposed that the hiccup is an evolutionary remnant of earlier
amphibian respiration.[12] Amphibians such as tadpoles gulp air and water across
their gills via a rather simple motor reflex akin to mammalian hiccuping. The motor
pathways that enable hiccuping form early during fetal development, before the
motor pathways that enable normal lung ventilation form. Thus, the hiccup is
evolutionarily antecedent to modern lung respiration. Additionally, this group points
out that hiccups and amphibian gulping are inhibited by elevated CO2 and may be
stopped by GABAB receptor agonists, illustrating a possible shared physiology and
evolutionary heritage. These proposals may explain why premature infants spend 2.5%
of their time hiccuping, possibly gulping like amphibians, as their lungs are not yet
fully formed. Fetal intrauterine hiccups are of two types. The physiological type
occurs prior to twenty-eight weeks after conception and tend to last five to ten
minutes. These hiccups are part of fetal development and are associated with the
myelination of the phrenic nerve, which primarily controls the thoracic diaphragm.
The phylogeny hypothesis explains how the hiccup reflex might have evolved, and if
there is not an explanation it may explain hiccups as an evolutionary remnant, heldover from our amphibious ancestors. This hypothesis has been questioned because of
the existence of the afferent loop of the reflex, the fact that it does not explain
the reason for glottic closure, and because the very short contraction of the hiccup
is unlikely to have a significant strengthening effect on the slow-twitch muscles of
respiration.
Straus C, Vasilakos K, Wilson RJ, Oshima T, Zelter M, Derenne JP, Similowski T, Whitelaw WA (February 2003). "A phylogenetic
hypothesis for the origin of hiccough". BioEssays. 25 (2): 182–188. doi:10.1002/bies.10224.
Jump up ^ P. Kahrilas and G. Shi (1997). "Why do we hiccup?". Gut. 41 (5): 712–713. doi:10.1136/gut.41.5.712. PMC 1891574Freely
accessible.
Mediastinum
The mediastinum (from
Medieval Latin
mediastinus, "midway") is
the central compartment
of the thoracic cavity
surrounded by loose
connective tissue, as an
undelineated region that
contains a group of
structures within the
thorax. The mediastinum
contains the heart and its
vessels, the esophagus,
trachea, phrenic and
cardiac nerves, the
thoracic duct, thymus and
lymph nodes of the
central chest.
Mediastinum
Mediastinum
[email protected]
[email protected]