In this PPT I completed that interesting topic In this PPT I completed that interesting topic , molecular embryology discussing this time molecular regulation of some other systems in the developing embryo, wishing that I could make this as simple as possible.
This PPT is a simplified introduction for molecular embryology. It includes molecular regulation of Heart, GIT, Liver, Pancreas, Kidney and somites Development. This will be followed by another PPT with molecualr regulation of other important organs as Brain and spinal cord. I hope that I could make it as simple as possible, waiting for your valuable comments. Enjoy my dear friends.
Embryonic Gastrulation by Maryam Borhani-Haghighiborhanihm
Gastrulation is a phase in the embryonic development during which the single-layered blastula is reorganized into a trilaminar ("three-layered") structure known as the gastrula.
This PPT is a simplified introduction for molecular embryology. It includes molecular regulation of Heart, GIT, Liver, Pancreas, Kidney and somites Development. This will be followed by another PPT with molecualr regulation of other important organs as Brain and spinal cord. I hope that I could make it as simple as possible, waiting for your valuable comments. Enjoy my dear friends.
Embryonic Gastrulation by Maryam Borhani-Haghighiborhanihm
Gastrulation is a phase in the embryonic development during which the single-layered blastula is reorganized into a trilaminar ("three-layered") structure known as the gastrula.
Development of the musculoskeletal systemSahar Hafeez
In this presentation you will learn about the development of Musculoskeletal system, one of the major systems of human body. The presentation briefly highlights upon the process of bone formation during the intrauterine life. It also describes the origin of two main groups of muscles in the body, the Extensors & Flexors and their motor innervation pattern.
05.28.09(a): Development of the Gastrointestinal System Open.Michigan
Slideshow is from the University of Michigan Medical
School's M1 Embryology sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Embryology
What data indicate that all three germ layers are specified in the b.pdfherminaherman
What data indicate that all three germ layers are specified in the blastula? What are the
differences between dorsal and ventral mesodermal derivatives and what cellular interactions are
required for their specification?
Solution
Three germ layers of amphibians are specified in the blastula is determined by isolating these
tissues in vitro, and they are able to form into specific germ layers. The animal pole cap cells
make ectoderm, marginal region cells make mesoderm, and vegetal cells make endoderm.
Theyare specified but not determined. It is also interesting to note that if animal cap cells are
place co-cultured with vegetal cells, the animal cap cells with become mesoderm. This indicates
that vegetal cells induce other cells to form mesoderm. Experiment paired animal cap cells in 4
different sections of vegetal blastomeres to see if they induce different dorsal-ventral
mesodermal fates. Result showed that different sections of vegetal blastomere have specific
inductive capacities, which is crucial for dorsal-ventral mesoderm determination. Difference
between dorsal and ventral mesoderm derivatives: dorsal mesoderm is the notochord and somite.
In all bilaterian animals, the mesoderm is one of the three primary germ layers in the very early
embryo. The other two layers are the ectoderm (outside layer) and endoderm (inside layer), with
the mesoderm as the middle layer between them.
The mesoderm forms mesenchyme, mesothelium, non-epithelial blood cells and coelomocytes.
Some of the mesoderm derivatives include the muscle (smooth, cardiac and skeletal), the
muscles of the tongue (occipital somites), the pharyngeal arches muscle (muscles of mastication,
muscles of facial expressions), connective tissue, dermis and subcutaneous layer of the skin
At mid-blastula two signaling centers are present on the dorsal side: The prospective
neuroectoderm expresses bone morphogenetic protein (BMP) antagonists, and the future dorsal
endoderm secretes Nodal-related mesoderm-inducing factors. When dorsal mesoderm is formed
at gastrula, a cocktail of growth factor antagonists is secreted by the Spemann organizer and
further patterns the embryo. A ventral gastrula signaling center opposes the actions of the dorsal
organizer, and another set of secreted antagonists is produced ventrally under the control of
BMP4. The early dorsal -Catenin signal inhibits BMP expression at the transcriptional level and
promotes expression of secreted BMP antagonists in the prospective central nervous system
(CNS). In the absence of mesoderm, expression of Chordin and Noggin in ectoderm is required
for anterior CNS formation. FGF (fibroblast growth factor) and IGF (insulin-like growth factor)
signals are also potent neural inducers. Neural induction by anti-BMPs such as Chordin requires
mitogen-activated protein kinase (MAPK) activation mediated by FGF and IGF. These multiple
signals can be integrated at the level of Smad1. Phosphorylation by BMP receptor stimulates
Smad1 transcrip.
A Review on Genetic Dominant Disorder-Polydactylyijtsrd
Polydactyly is genetic disorder in which there is mutation of gene that is located on short arm of chromosome 7. One gene that can cause polydactyly is GLI3 and it is one among number of genes that are known to be involved in the patterning of tissues and organs during development of the embryo. Mutations of GLI3 gene during development will cause two types of polydactyly. Those are postaxial ulnar and preaxial radial polydactyly. The treatment plan is based on the outcome of analysis of patients medical history, social history, motivation, social and psychological disturbance. Akshata. B. Kichadi | Dr. Uma B Gopal | Santhosh Singarapu | Chaitra. S | Manukrishnan. K | Jeevankumar. Giri "A Review on Genetic Dominant Disorder-Polydactyly" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-2 , February 2019, URL: https://www.ijtsrd.com/papers/ijtsrd20232.pdf
Paper URL: https://www.ijtsrd.com/medicine/anatomy/20232/a-review-on-genetic-dominant-disorder-polydactyly/akshata-b-kichadi
Phloem differentiation
sieve elements
companion cells
The ontogeny of phloem sieve element
differentiation process of sieve elements
Phloem as a hub for systemic communication within the root meristem
cell lineage , cell fate - diverse class of cell fate, cell fate in plant meristem, mammalian development cell fate, nutritional effects on epigenetics, epigenetics of plants,
control of cell fate.
contains descriptive and other studies on genetics and epigenetics and whole gene concepts from central dogma to future concepts . Dr Harshavardhan Patwal
This presentation introduces a brief and rapid review for an important research area (oxidative stress) and its relation to liver fibrosis.
Liver fibrosis is very important for us as we are facing a very dangerous and continuously growing problem in Egypt, HEPATIC PATIENTS COMPLICATIONS.
This is a presentation for 1st year medical students, Anatomy course, Mansoura Faculty of Medicine,Mansoura University,Mansoura,Egypt.
We are talking about the upper limb skeleton, starting with general features of three bones which are:
Clavicle, Scapula & Humerus.
I hope you can get benefit of it.
Enjoy my friends.....
In this PPT I completed that interesting topic , molecular embryology discussing this time molecular regulation of some other systems in the developing embryo, wishing that I could make this as simple as possible.
Khaled El Masry, is an assistant Lecturer of Human Anatomy & Embryology, Mansoura University, Egypt. Great thanks to Prof. Dr Salwa Gawish, professor of Cytology & Histology, Mansoura University, for her great effort in explaining Genetics course.
Unlocking Productivity: Leveraging the Potential of Copilot in Microsoft 365, a presentation by Christoforos Vlachos, Senior Solutions Manager – Modern Workplace, Uni Systems
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The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
SAP Sapphire 2024 - ASUG301 building better apps with SAP Fiori.pdfPeter Spielvogel
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• What is SAP Fiori and why it matters to you
• How a better user experience drives measurable business benefits
• How to get started with SAP Fiori today
• How SAP Fiori elements accelerates application development
• How SAP Build Code includes SAP Fiori tools and other generative artificial intelligence capabilities
• How SAP Fiori paves the way for using AI in SAP apps
Securing your Kubernetes cluster_ a step-by-step guide to success !KatiaHIMEUR1
Today, after several years of existence, an extremely active community and an ultra-dynamic ecosystem, Kubernetes has established itself as the de facto standard in container orchestration. Thanks to a wide range of managed services, it has never been so easy to set up a ready-to-use Kubernetes cluster.
However, this ease of use means that the subject of security in Kubernetes is often left for later, or even neglected. This exposes companies to significant risks.
In this talk, I'll show you step-by-step how to secure your Kubernetes cluster for greater peace of mind and reliability.
Threats to mobile devices are more prevalent and increasing in scope and complexity. Users of mobile devices desire to take full advantage of the features
available on those devices, but many of the features provide convenience and capability but sacrifice security. This best practices guide outlines steps the users can take to better protect personal devices and information.
GraphSummit Singapore | The Future of Agility: Supercharging Digital Transfor...Neo4j
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This keynote will reveal how Deloitte leverages Neo4j’s graph power for groundbreaking digital twin solutions, achieving a staggering 100x performance boost. Discover the essential role knowledge graphs play in successful generative AI implementations. Plus, get an exclusive look at an innovative Neo4j + Generative AI solution Deloitte is developing in-house.
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Join Maher Hanafi, VP of Engineering at Betterworks, in this new session where he'll share a practical framework to transform Gen AI prototypes into impactful products! He'll delve into the complexities of data collection and management, model selection and optimization, and ensuring security, scalability, and responsible use.
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My slides at Nordic Testing Days 6.6.2024
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The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
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Why are attacks on smart factories rising?
Cyber risk predictions
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Molecular embryology part (2)
1. By:
Dr. Khaled El Masry
Assistant Lecturer of Human Anatomy &
Embryology
Mansoura Faculty of Medicine, Mansoura University,
Mansoura , Egypt.
Molecular Embryology
2013
4/28/2013
2. 4/28/2013
All Data and Diagrams included
in this presentation are basically
derived from our highly
valuable reference of
Embryology
(Langman's Medical
Embryology 12th ed. - T.
Sadler (Lippincott, 2012)
, recommending you all to refer
to it for more details….
4. Molecular Biology has opened the doors to new ways
to study Embryology and to enhance our
understanding of Normal and Abnormal development.
Sequencing the Human Genome, together with
creating techniques to investigate gene regulation at
many levels of complexity, has taken Embryology to
the next level.
Thus, from Anatomical to Biochemical to
MOLECULAR level, the story of Embryology has
progressed, and each chapter has enhanced our
knowledge.
4/28/2013
5. Genes are contained in a complex of DNA and proteins called chromatin, and
its basic unit of structure is the nucleosome. Chromatin appears tightly coiled
as beads of nucleosomes on a string and is called heterochromatin.
For transcription to occur, DNA must be uncoiled from the beads as
euchromatin. Genes reside within strands of DNA and contain regions that can
be translated into proteins, called exons, and untranslatable regions, called
introns.
A typical gene also contains :
1. a promoter region that binds RNA polymerase for the initiation of transcription;
2. a transcription initiation site, to designate the first amino acid in the protein;
3. a translation termination codon; and
4. a 3′ untranslated region that includes a sequence (the poly A addition site)
that assists with stabilization of the mRNA.
4/28/2013
7. The RNA polymerase binds to the promoter region that usually
contains the sequence TATA, the TATA box. Binding requires
additional proteins called transcription factors. Methylation of
cytosine bases in the promoter region silences genes and
prevents transcription.
Different proteins can be produced from a single gene by the
process of alternative splicing that removes different introns
using spliceosomes. Proteins derived in this manner are called
splicing isoforms or splice variants. Also, proteins may be
altered by post- translational modifi cations, such as
phosphorylation or cleavage.
4/28/2013
9. Induction is the process whereby one group of cells or tissues (the
inducer) causes another group (the responder) to change their fate.
The capacity to respond is called competence and must be conferred
by a competence factor.
Many inductive phenomena involve epithelial– mesenchymal
interactions.
Signal transduction pathways include a signaling molecule (the
ligand) and a receptor.The receptor usually spans the cell membrane
and is activated by binding with its specific ligand.
Activation usually involves the capacity to phosphorylate other
proteins, most often as a kinase. This activation establishes a cascade
of enzyme activity among proteins that ultimately activates a
transcription factor for initiation of gene expression.
4/28/2013
11. Cell-to-cell signaling may be paracrine, involving diffusable
factors, or juxtacrine, involving a variety of nondiffusable factors.
Proteins responsible for paracrine signaling are called paracrine
factors or growth and differentiation factors (GDFs).
There are four major families of GDFs:
FGFs, WNTs, hedgehogs, and TGF-bs.
In addition to proteins, neurotransmitters, such as serotonin (5HT)
and norepinephrine, also act through paracrine signaling, serving as
ligands and binding to receptors to produce specific cellular
responses.
Juxtacrine factors may include products of the extracellular
matrix, ligands bound to a cell’s surface, and direct cell-to-cell
communications. 4/28/2013
15. 4/28/2013
Establishment of the body axes;
anteroposterior, dorsoventral, and left-right, takes
place before and during the period of gastrulation.
Cells at the prospective cranial end of
the embryo in the anterior visceral
endoderm (AVE) express the
transcription factors OTX2, LIM1, and
HESX1 and the secreted factor
cerberus that contribute to head
development and establish the
cephalic region.
Goosecoid, expressed in the node, regulates chordin
expression, and this gene product, together with noggin and
follistatin, antagonizes the activity of BMP4, dorsalizing mesoderm
into notochord and paraxial mesoderm for the head region.
Once the streak is formed and gastrulation is progressing, BMP4 is
secreted throughout the bilaminar disc and acts with FGF to
ventralize mesoderm into intermediate and lateral plate mesoderm.
Later, expression of the Brachyury (T) gene antagonizes BMP4 to
dorsalize mesoderm into notochord and paraxial mesoderm in caudal
regions of the embryo.
16. 4/28/2013
FGF8, secreted by the node and
primitive streak, establishes
expression of Nodal, a member of
the TGF-b superfamily, and the nodal
protein then accumulates on the left
side near the node.
Later, as the neural plate starts to
form, FGF8 induces expression of
Nodal and LEFTY-2 in the lateral
plate mesoderm, whereas LEFTY-1
is expressed on the left side of the
ventral aspect of the neural tube.
17. 4/28/2013
These signals are dependent upon
serotonin (5HT). Products from the
Brachyury (T) gene, expressed in the
notochord, also participate in induction of
these three genes.
In turn, expression of Nodal and
LEFTY-2 regulates expression of the
transcription factor PITX
2, which, through further downstream
effectors, establishes left-sidedness.
SHH, expressed in the notochord, may
serve as a midline barrier and also
represses expression of left-sided genes
on the right. Expression of the
transcription factor Snail may regulate
downstream genes important for
establishing right-sidedness.
18. 4/28/2013
Cells migrating more posteriorly
through the node and most cranial
aspect of the streak will form
paraxial mesoderm (pm;
somitomeres and somites);
Fate map established during
gastrulation
Cells migrating at the most
cranial part of the node will
form the notochord (n);
Cells migrating through the next portion
of the streak will form intermediate
mesoderm (im; urogenital system);
Cells migrating through the more caudal
part of the streak will form lateral plate
mesoderm (lpm; body wall);
Cells migrating through the most
caudal part will contribute to
extraembryonic mesoderm (eem;
chorion).
25. Crest cells originating from Rhombomeres migrate to specific
arches
Patterning of pharyngeal
arches
This is regulated
by
1st Arch 2nd to 6th Arch
By
OTX 2 gene
MidbrainandForebrainExpressed in
regions and migrate with crest cells to
1st arch.
By
HOX genes
inHindbrainExpressed in
specific overlapping
pattern
There may be
an interaction
with HOX
genes in 1st
arch
patterning
4/28/2013
26. HOX
genes
Crest cells alone can’t maintain HOX genes
expression but require interaction with
mesoderm of the pharyngeal arches
HOX expression is
regulated by
SHH
Upstream regulator
expressed in the
arches
Regulate HOX expression in concentration
RAREdependent manner via
Retinoi
c Acid
: ( Retinoic Acid Response Elements)RARE
Binding sites for retinoic acid in promoter regions of HOX genes4/28/2013
28. 4/28/2013
Patterns of HOX gene expression in the
hindbrain. HOX genes are expressed in overlapping
patterns
ending at specifi c rhombomere boundaries. Genes
at
the 3′ end of a cluster have the most anterior
boundaries,
and paralogous genes have identical expression
domains.
These genes confer positional value along the
anteriorposterior
axis of the hindbrain, determine the identity of
the rhombomeres, and specify their derivatives.
32. Forebrain
&
Midbrain
Inhibition of BMP 4
Chordin
Noggin
Follistati
n
B
y
Expression of ( OTX 1,2 , EMX1, EMX2) genes in specific
& overlapping pattern
Differentiation of Forebrain & Midbrain
Regions
Once Boundaries of Forebrain & Midbrain Regions are
established
2 additional Organizing Centers appear
ANR
( at the junction of cranial border of
neural plate & non- neural
ectoderm
Isthmus
( at the junction Midbrain &
Hindbrain)
4/28/2013
35. Hindbrain
WNT 3a & FGF
Induce differentiation of
Hindbrain region into 8
segments called
Rhombomeres
Express HOX
genes
Expressed in overlapping pattern
Determine identity of these Rhombomeres & specify their
derivatives
Retinoic Acid Organizes Craniocaudal Axis
4/28/2013
36. 4/28/2013
Patterns of HOX gene expression in the
Hindbrain:
HOX genes are expressed in overlapping patterns
ending at specifi c rhombomere boundaries. Genes at
the 3′ end of a cluster have the most anterior boundaries,
and paralogous genes have identical expression domains.
These genes confer positional value along the
anteriorposterior
axis of the hindbrain, determine the identity of
the rhombomeres, and specify their derivatives.
37. Spinal
Cord
Induced byWNT 3a &
FGF
Neural plate in spinal cord region
expresses the following
Transcription Factors
(PAX3, PAX7, MSX1, MS
X2)
This expression is
controlled by
SHH (secreted by prochordal
plate)
Inhibit their
expression
Ventralize the Neural plate
Motor Neurons formation
BMP4,7(secreted by Non-neural
Ectoderm)
Upregulate PAX3,7
Dorsalize the Neural plate
Sensory Neurons
formation
needed for
Neural
Crest cells
formation
4/28/2013
39. Limb outgrowth is initiated by FGF10 secreted by
lateral plate mesoderm in the limb-forming regions
Once outgrowth is initiated, the AER is induced by
BMPs and restricted in its location by the gene
Radical fringe expressed in dorsal ectoderm. In
turn, this expression induces that of SER2 in cells
destined to form the AER.
After the ridge is established, it
expresses FGF4 and FGF8 to maintain
the progress zone, the rapidly
proliferating mesenchyme cells adjacent
to the ridge.
4/28/2013
40. Anteroposterior patterning of the limb is controlled
by cells in the ZPA at the posterior border.
These cells produce retinoic acid (vitamin A), which
initiates expression of SHH, regulating patterning.
The dorsoventral limb axis is directed by
WNT7a, which is expressed in the dorsal
ectoderm.
This gene induces expression of the
transcription factor LMX1 in the dorsal
mesenchyme, specifying these cells as
dorsal.
4/28/2013
41. 4/28/2013
Longitudinal section through the
limb bud of a chick
embryo, showing a core of
mesenchyme cover by a layer of
ectoderm that thickens at the distal
border of the limb to form the AER.
In humans, this occurs during the
fifth week of development.
External view of a chick limb at
high magnification showing the
ectoderm and the specialized
region at the tip of the limb called
the AER
42. Bone type and shape are regulated by HOX genes, whose
expression is determined by the combinatorial expression of
SHH, FGFs, and WNT7a.
HOXA and HOXD clusters are the primary determinants of bone
morphology.
4/28/2013
44. The eyes begin to develop as a pair of outpocketings that will
become the optic vesicles on each side of the forebrain at the end
of the fourth week of development .
The optic vesicles contact the surface ectoderm and induce lens
formation.
When the optic vesicle begins to invaginate to form the pigment
and neural layers of the retina, the lens placode invaginates to form
the lens vesicle.
Through a groove at the inferior aspect of the optic vesicle, the
choroid fissure, the hyaloid artery (later the central artery of the
retina) enters the eye .
Nerve fibers of the eye also occupy this groove to reach the optic
areas of the brain.
The cornea is formed by:
(a) a layer of surface ectoderm,
(b) the stroma, which is continuous with the sclera, and 4/28/2013
47. The master gene for
Eye Development
PAX
6
Expressed in the single eye field at the neural
plate stage.
SHH
Separate the
eye field into
two optic
primordia.
upregulates
PAX2 expression in
the optic stalks
while
downregulating
PAX6.
Restricting
(PAX6)expressio
n to the optic cup
and lens
Epithelial–mesenchymal interactions between prospective lens
ectoderm, optic vesicle, and surrounding mesenchyme then
regulate lens and optic cup differentiation.
4/28/2013
49. Teeth develop from epithelial–mesenchymal interactions
between oral epithelium and neural crest–derived
mesenchyme.
Enamel is made by ameloblasts.
It lies on a thick layer of dentin produced by
odontoblasts,
a neural crest derivative.
Cementum is formed by cementoblasts, another
mesenchymal derivative found in the root of the tooth.
4/28/2013
50. Enamel Knot
(Circumscribed
Region of dental
epith. at tips oftooth
buds
The organizer for the
TOOTH
Development is
Express
FGF 4 BMP 4
Regulate
outgrowth of the
cap.
Regulate timing of
apoptosis in Knot
cells 4/28/2013