This document discusses stem cells, including their characteristics and different types. It begins with an introduction to stem cells, noting they are unspecialized cells that can divide indefinitely and give rise to specialized cells. It then describes the main characteristics of stem cells, including being unspecialized, capable of proliferation, able to differentiate, and demonstrating plasticity. The document discusses the different types of stem cells, including totipotent stem cells found in early embryos, pluripotent stem cells which can form any cell type but not placental cells, and multipotent adult stem cells which are limited to certain cell lineages. Sources of stem cells discussed include embryonic stem cells isolated from blastocysts, adult stem cells found in tissues, and
A stem cell is a "blank" cell that can give rise to multiple tissue types such as a skin, muscle, or nerve cell.
Under certain physiologic or experimental conditions, they can be induced to become tissue- or organ-specific cells with special functions.
What are stem cells? This presentation provides an overview of multiple different stem cells including embryonic stem cells, mesenchymal stem cells, cancer stem cells, induced pluripotent stem cells, hematopoietic stem cells and neural stem cells.
This presentation describes in detail the various types and sources of stem cells. it also describes the stem cell therapies used to treat various diseases.
A stem cell is a "blank" cell that can give rise to multiple tissue types such as a skin, muscle, or nerve cell.
Under certain physiologic or experimental conditions, they can be induced to become tissue- or organ-specific cells with special functions.
What are stem cells? This presentation provides an overview of multiple different stem cells including embryonic stem cells, mesenchymal stem cells, cancer stem cells, induced pluripotent stem cells, hematopoietic stem cells and neural stem cells.
This presentation describes in detail the various types and sources of stem cells. it also describes the stem cell therapies used to treat various diseases.
Stem cells
Undifferentiated cells capable of self-renew and to differentiate into different cell types or tissues during embryonic development and throughout adulthood.
Have possibility to become a specialised cell.
Have the ability to divide continuously and develop into various other kinds of cells.
Have immune potential and can help to treat a wide range of medical problems.
Discovery of stem cells lead to a whole new branch of medicine known as Regenerative medicine.
A knockout mouse is a mouse in which a specific gene has been inactivated or“knocked out” by replacing it or disrupting it with an artificial piece of DNA.
The loss of gene activity often causes changes in a mouse's phenotype and thus provides valuable information on the function of the gene.
WHAT IS EMBRYONIC STEM CELL?
TYPES OF EMBRYONIC STEM CELL
RECENT RESEARCH OF EMBRYONIC STEM CELL
ADVANTAGES OF EMBRYONIC STEM CELL
LIMITATION OF EMBRYONIC STEM CELL.
Stem cells
Undifferentiated cells capable of self-renew and to differentiate into different cell types or tissues during embryonic development and throughout adulthood.
Have possibility to become a specialised cell.
Have the ability to divide continuously and develop into various other kinds of cells.
Have immune potential and can help to treat a wide range of medical problems.
Discovery of stem cells lead to a whole new branch of medicine known as Regenerative medicine.
A knockout mouse is a mouse in which a specific gene has been inactivated or“knocked out” by replacing it or disrupting it with an artificial piece of DNA.
The loss of gene activity often causes changes in a mouse's phenotype and thus provides valuable information on the function of the gene.
WHAT IS EMBRYONIC STEM CELL?
TYPES OF EMBRYONIC STEM CELL
RECENT RESEARCH OF EMBRYONIC STEM CELL
ADVANTAGES OF EMBRYONIC STEM CELL
LIMITATION OF EMBRYONIC STEM CELL.
Stem cell therapy is the use of stem cells to treat or prevent a disease or condition. Bone marrow transplant is the most widely used stem cell therapy, but some therapies derived from umbilical cord blood are also in use.
"stem cells known to be a blank or undifferentiated cells act as revolutionized medicine by bringing a prolong life to millions of people for survival and also by creating a better hope to the research field"
Stem cells are unspecialized cells that are thought to be able to reproduce themselves indefinitely and under the right conditions, to develop into a wide variety of mature cells with specialized functions.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
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micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
2. INTRODUCTION
• Stem cells are one of the most fascinating
areas of biology today.
Stem cells are a special kind of cell that
have the ability to divide indefinitely and
have the potential to give rise to specialized
cells (that is, any cell of the body).
Dr. Monika Nema
3. Dr. Monika Nema
Stem Cell Characteristics
‘Blank cells’ (unspecialized)
Capable of dividing and renewing
themselves for long periods of time
(proliferation and renewal)
Have the potential to give rise to
specialized cell types (differentiation)
Plasticity
4. Unique properties of all stem cells
1] Stem cells are unspecialized
One of the fundamental properties of stem cells is that
it does not have any tissue specific structures that
allow it to perform specialized function.
2] Proliferation
They are capable of dividing and renewing
themselves for indefinite periods
5. Contd.
3]Differentiation
They can give rise to specialized tissue. Under certain
physiological and experimental conditions unspecialized cell
can give rise to specialized cells such as including heart
muscle cells, blood cells or nerve cells required to repair
damaged or depleted adult cell population or tissue.
4]Plasticity
Stem cell from one tissue may be able to give rise to cell types
of completely different tissue , a phenomenon known as
plasticity. e.g. Blood cells becoming neuron, liver cells
producing insulin and haematopoietic stem cells, developing
into heart muscle.
8. This cell
Can form the
Embryo and placenta
This cell
Can just form the
embryo
Fully matureDr. Monika Nema
9. Terminology
►Totipotent cells. These cells have the potential
to become
– any type in the adult body;
– any cell of the extraembryonic membranes (e.g.,
placenta).
►The only totipotent cells are the fertilized egg
and the first 4 or so cells produced by its
cleavage (as shown by the ability of mammals to
produce identical twins, triplets, etc.).
Dr. Monika Nema
10. ►Pluripotent stem cells. These are true stem
cells, with the potential to make any
differentiated cell in the body (but probably
not those of the placenta which is derived
from the trophoblast).
Dr. Monika Nema
12. Two types of pluripotent stem cells have been found
– Embryonic Stem (ES) Cells. These can be isolated from
the inner cell mass (ICM) of the blastocyst — the stage of
embryonic development when implantation occurs. For
humans, excess embryos produced during
in vitro fertilization (IVF) procedures are used.
– Embryonic Germ (EG) Cells. are derived from the part of
a human embryo or foetus that will ultimately produce eggs
or sperm (gametes).
Dr. Monika Nema
13. These types of pluripotent stem cells
– can only be isolated from embryonic or fetal
tissue;
– can be grown in culture, but only with special
methods to prevent them from differentiating.
Dr. Monika Nema
14. Dr. Monika Nema
Tens of thousands of frozen
embryos are routinely
destroyed when couples finish
their treatment.
These surplus embryos
can be used to produce
stem cells.
Regenerative medical
research aims to develop
these cells into new,
healthy tissue to heal
severe illnesses.
15. Dr. Monika Nema
Somatic Cell Nuclear
Transfer
The nucleus of a donated
egg is removed and
replaced with the nucleus
of a mature, "somatic cell"
(a skin cell, for example).
No sperm is involved in
this process, and no
embryo is created to be
implanted in a woman’s
womb.
The resulting stem cells
can potentially develop into
specialized cells that are
useful for treating severe
illnesses.
16. How are embryonic stem cells
harvested?
• Growing cells in the laboratory is called as cell culture.
• Human ES cells are derived from 4-5 day old blastocyst
• Blastocyst structures include:
– Trophoblast: outer layer of cells that surrounds the blastocyst
& forms the placenta
– Blastocoel: (“blastoseel”) the hollow cavity inside the
blastocyst that will form body cavity
– Inner cell mass: a group of approx. 30 cells at one end of the
blastocoel:
• Forms 3 germ layers that form all embryonic tissues (endoderm,
mesoderm, ectoderm) Dr. Monika Nema
17. Stages of Embryogenesis
Day 1
Fertilized egg
Day 2
2-cell embryo
Day 3-4
Multi-cell embryo
Day 5-6
BlastocystDay 11-14
Tissue Differentiation
Dr. Monika Nema
18. Blastocyst -
from In Vitro Fertilization Clinic
Inner Cell Mass
(Stem Cells)
“Blueprint” cells
A primer on Human Embryonic Stem Cells
A Blastocyst is a hollow ball of cells with
a small clump of stem cells inside
Dr. Monika Nema
19. “Blueprint”
cells
Human Embryonic Stem Cells
Pipette
Stem Cells
To remove the stem cells, the Blastocyst is opened and
the stem cells removed with a pipette
Blastocyst -
from In Vitro Fertilization Clinic
Stem Cells “Blueprint” cells
A Blastocyst is a hollow ball of cells with a
small clump of stem cells inside
Dr. Monika Nema
20. Pipette
Pipette
Stem Cells
Petri Dish
Human Embryonic Stem Cells
To remove the stem cells, the Blastocyst is
broken open and the stem cells removed with
a pipette(an ultra thin glass tube)
The stem cells are
placed in a
dish and are fed and
cared for
(each blastocyst =
1 stem cell line)
Blastocyst -
from In Vitro Fertilization Clinic
Stem Cells “Blueprint” cells
A Blastocyst is a hollow ball of cells with a
small clump of stem cells inside
Stem Cells
“Blueprint”
cells
Dr. Monika Nema
22. Cell Culture Techniques for ESC
• Isolate & transfer of inner cell mass into
plastic culture dish that contains culture
medium
• Cells divide and spread over the dish
• Inner surface of culture dish is typically coated
with mouse embryonic skin cells that have
been treated so they will not divide
Dr. Monika Nema
23. • This coating is called a FEEDER LAYER
– Feeder cells provide ES cells with a sticky surface
for attachment
– Feeder cells release nutrients
• Recent discovery: methods for growing
embryonic stem cells without mouse feeder
cells
– Significance – eliminate infection by viruses or
other mouse molecules
• ES cells are removed gently and plated into
several different culture plates before crowding
occurs
Dr. Monika Nema
24. ►Over the course of several days the inner cell mass proliferate
and begin to crowd the culture dish.
►They are then gently removed and plated into several fresh
culture dishes.
– The process of plating the cells is repeated several times and for many
months and is called subculturing .
– Each cycle of subculturing is referred to as a passage.
►After six months or more the inner cell mass yield millions of
embryonic stem cells. These cells are pluripotent and appear
genetically normal and are referred to as an embryonic stem cell
line.
Dr. Monika Nema
26. Multipotent stem cells
►These are true stem cells but can only differentiate
into a limited number of types.
– For example, the bone marrow contains multipotent stem
cells that give rise to all the cells of the blood but not to
other types of cells.
►Multipotent stem cells are found in adult animals;
perhaps most organs in the body (e.g., brain, liver)
contain them where they can replace dead or
damaged cells.
►These adult stem cells may also be the cells that —
when one accumulates sufficient mutations —
produce a clone of cancer cells.
Dr. Monika Nema
28. Adult Stem Cells
►An adult stem cell also called as somatic stem cells are an
undifferentiated cells found among differentiated cells in a
tissue or an organ which can renew itself and can differentiate
to yield the major specialized cell type of the tissue or the
organ.
►Primary role of adult stem cell is to maintain and repair the
tissue in which they are found.
►Their origin is unknown
– Haematopoietic stem cells – form all type of blood cells
– Stromal cells – can generate cartilage, fat, and fibrous connective tissue
– Brain stem cells – astrocytes , oligodendrocytes and neurons
Dr. Monika Nema
31. Adult stem cells
►Contrary to the ES cells, which are
pluripotent, adult stem cells have a more
restricted differentiation capacity and are
usually lineage specific.
►Present in bone marrow and other tissues.
►Stem cells outside bone marrow are called
as tissue stem cells.
►In the tissue, stem cells are located in the
sites called niches.
Dr. Monika Nema
32. Stem cells niches in various tissuesH
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33. Embryonic vs Adult Stem Cells
• Totipotent
– Differentiation into ANY
cell type
• Known Source
• Large numbers can be
harvested from embryos
• May cause immune
rejection
– Rejection of ES cells by
recipient has not been
shown yet
• Multi or pluripotent
– Differentiation into some
cell types, limited outcomes
• Unknown source
• Limited numbers, more
difficult to isolate
• Less likely to cause
immune rejection, since the
patient’s own cells can be
used
Dr. Monika Nema
34. Cord Blood
• Umbilical cord blood is also known as
placental blood.
• It is the blood that flows in the
circulation of the developing fetus in the
womb.
• After the baby’s birth, the left over
blood in the umbilical cord and placenta
is called cord blood.
• This blood is a rich source of stem cells.
35. Umbilical cord stem cells
• Umblical cord blood is a rich source of primitive
stem cells as compared to adult stem cells. Therefore
these are able to expand rapidly.
• Stored cord blood stem cells from a child is the
perfect match for that child. This allows for an
autologous transplant if needed, with no risk of Graft-
vs- Host Disease(GVHD).
• Cord blood stem cells are a close match for siblings
or family members in case of need, with low risk of
GVHD.
Dr. Monika Nema
36. Making a decision to collect
baby’s cord blood stem cells.
• Yes, if there is a family history of
malignant, benign or inherited disorders.
• Yes, even in the absence of “health risk
factors”, as there are potential benefits to
family in the future.
• Yes, if the costs are affordable and this
is something of value.
• Yes, it is the one chance to collect them.
37. Collecting cord blood stem cells
• This blood is collected by the physician after
the baby is born and the cord is cut.
• It takes less than 5 minutes and there is no
pain, harm or risk to mother or newborn.
• This cord blood containing the stem cells, is
sent to a “Cord Blood Bank” either private or
public where it is processed and the stem cells
are preserved in liquid nitrogen.
38. ►Immediately after a baby is delivered umbilical cord
is clamped . After delivery of placenta , the placenta
is placed on supporting frame , the cord is cleaned
and needle is inserted into the umbilical vein . The
umbilical cord blood is collected in a closed system
and blood drained as a “standard gravity
phlebotomy.”
Dr. Monika Nema
39. .
o Second method involves collecting the cord blood
while the placenta is still in the mother’s womb.
This method has theoretically two advantages
collection begins earlier before the blood has a
chance to clot.
It uses the contraction of the uterus to enhance the
blood drainage in addition to the gravity.
Disadvantage: it is more intrusive and has the
potential to interfere with after-delivery care for
the mother and infant.
o The cord blood collected from single placenta is
called a cord blood unit ranging from 60-120 ml
Dr. Monika Nema
40. Umbilical cord stem cells
• Adult stem cells of infant origin
• Greater compatibility
• Less expensive
Dr. Monika Nema
41. Umbilical cord stem cells
Three important functions:
1. Plasticity: Potential to change into other cell types
like nerve cells
2. Homing: To travel to the site of tissue damage
3. Engraftment: To unite with other tissues
Dr. Monika Nema
42. Potential Uses of Stem Cells
• Basic research – clarification of complex
events that occur during human
development & understanding molecular
basis of cancer
– Molecular mechanisms for gene control
– Role of signals in gene expression &
differentiation of the stem cell
– Stem cell theory of cancer
Dr. Monika Nema
43. Potential uses
• Biotechnology (drug discovery &
development) – stem cells can provide specific
cell types to test new drugs
– Safety testing of new drugs on differentiated cell
lines.
– Screening of potential drugs
• Cancer cell lines are already being used to screen
potential anti-tumor drugs
• Availability of pluripotent stem cells would allow drug
testing in a wider range of cell types & to reduce animal
testing Dr. Monika Nema
44. Potential uses
• Cell based therapies:
– Regenerative therapy to treat Parkinson’s,
Alzheimer’s, ALS, spinal cord injury, stroke,
severe burns, heart disease, diabetes, osteoarthritis,
and rheumatoid arthritis
Dr. Monika Nema
55. • Definition
Any procedure where hematopoietic stem cells
of any donor and any source are given to a
recipient with intention of
repopulating/replacing the hematopoietic
system in total or in part.
Dr. Monika Nema
56. The Nobel Prize, 1990
E. Donnall Thomas
first succsessful HSCT in treatment of acute leukemias
Thomas ED, Lochte HL, Lu WC, Ferrebee JW. Intravenous infusion of bone marrow in patients
receiving radiation and chemotherapy. N. Engl. J. Med. 1957; 257: 491.
Dr. Monika Nema
57. Haematopoietic stem cells
►It is defined as the cell with the ability to achieve
long term reconstruction of both myeloid and
lymphoid lineage.
►Features :-
1. Remarkable regenerative capacity
2. Ability to home to marrow spaces following IV
injection. {mediated in par by interaction of
selectin on bone marrow endothelium and
integrin on early hematopoietic cells }
3. Ability to be cryopreserved.
Dr. Monika Nema
63. ►Marrow is obtained by multiple aspirations from the
posterior iliac crest under general or epidural
anesthesia.
►For larger quantity anterior crest or sternum can be
the site. Several skin puncture on each iliac crest and
multiple bone puncture are usually required.
►Target volume is 10-15 mg/kg of recipient or donor
weight , whichever is less.
►Marrow is collected in heparinized syringe and
filtered through 0.3-0.2 mm screen to remove the fat
and bony spicule.
Dr. Monika Nema
64. ►Further processing depend on the clinical
situation, such as
– Removal of RBCs to prevent hemolysis in ABO
incompatible transplants {In BMSCT ABO mismatch
is the most common}
– Removal of immunocompetent donor T cells to
prevent GVHD
– Attempts to remove possible contamination of tumour
cells in autologous transplantation.
►Marrow is usually transfused immediately after
harvesting, but delay of upto 24 hrs may occur
without adverse consequences.
Dr. Monika Nema
65. Peripheral blood {PB }
►These cells are now the most common source of stem cells for
HSCT .
►Peripheral blood stem cells {PBSC} are collected by
leokopheresis after the donor has been treated with
hematopoietic growth factors or a combination of
chemotherapy and growth factors. For pts. with malignancy
cyclophosphamide based chemotherapy and G –CSF are used.
►The donors are typically treated with growth factor for
4-6 days, following which the stem cells are collected in one
to two 4 hrs sessions.
►In autologous setting transplantation of >2.5 X 106
CD 34+ cells / kg leads to rapid and sustained engraftment.
Dr. Monika Nema
67. Peripheral Blood Stem Cell
Transplant
PBSCs are easier to collect than bone marrow stem cells, which must be
extracted from within bones. This makes PBSCs a less invasive treatment
option than bone marrow stem cells.
Dr. Monika Nema
69. Storage of haematopoietic stem cell
►Bone marrow cells can be cryopreserved for prolonged time.
This is necessary for autologous HSC because the cells must be
harvested months in advance of the transplant treatment.
►In allogenic transplants fresh HSC are preferred in order to avoid
cell loss that might occur during the freezing and thawing
process.
►The graft undergoes HLA typing, cell counts and testing for
viruses.
►Allogenic cord blood is stored frozen at a cord blood bank
because it is only obtainable at the time of child birth.
►To cryopreserved HSC a preservative
(dimethyl sulfoxide )DMSO, must be added and cells must be
cooled very slowly in a control rate freezer to prevent osmotic
cellular injury during ice crystal formation.
►HSC may be stored for years in a cryofreezer.
Dr. Monika Nema
70. ► Cellular characteristics of various sources of stem cells
► Cord blood progenitor cells have greater proliferative potential than that of
peripheral blood and marrow progenitor cells.
Cellular characteristicCellular characteristic sourcesource
Bone marrowBone marrow PeripheralPeripheral
bloodblood
Cord bloodCord blood
Stem cell contentStem cell content adequateadequate GoodGood LowLow
Progenitor cell contentProgenitor cell content AdequateAdequate HighHigh LowLow
T-cell contentT-cell content LowLow HighHigh Low ,Low ,
functionallyfunctionally
immatureimmature
Risk of tumor cellRisk of tumor cell
contaminationcontamination
HighHigh LowLow NotNot
applicableapplicable
Dr. Monika Nema
71. Clinical characteristics with various sources of
stem cellsCellularCellular
characteristiccharacteristic
sourcesource
PeripheralPeripheral
bloodblood
Bone marrowBone marrow Cord bloodCord blood
HLA MatchingHLA Matching CloseClose
matchingmatching
requiredrequired
CloseClose
matchingmatching
requiredrequired
LessLess
restrictiverestrictive
than otherthan other
EngraftmentEngraftment FastestFastest IntermediateIntermediate SlowestSlowest
Risk of acuteRisk of acute
GVHDGVHD
Same as inSame as in
bone marrowbone marrow
Same as inSame as in
peripheralperipheral
bloodblood
LowestLowest
Risk ofRisk of
chronic GVHDchronic GVHD
HighestHighest Lower thanLower than
peripheralperipheral
bloodblood
LowestLowest
Dr. Monika Nema
72. Indication for HSCT
• Neoplastic disorders
– Hematological malignancies
• Lymphomas (Hodgkin and non-Hodgkin)
• Leukemias (acute and chronic)
• Multiple myeloma
• MDS
– Solid tumors
• Non-neoplastic disorders
– Aplastic anemia
– Autoimmune diseases
– Immunodeficiency
– Inborn errors of metabolism
Dr. Monika Nema
76. Ethical issues concerning the use
of stem cells
• There are some problematic issues relating to research on stem cells
that mainly concern the origins and methods of stem cell production.
• Small numbers of adult stem cells can be found in the human body,
• The best sources of stem cells are fetuses and embryos.
• Fetal stem cell lines can be cultured from cells isolated from aborted
fetuses.
• Stem cells from embryos can be isolated from 5–7 day-old blastocysts.
• The collection of stem cells of both fetal and embryonic origins
involves destruction of the “donor” – the fetus or embryo – and this is
ethically problematic
Dr. Monika Nema
77. Key Ethical Issues
• The blastocyst used in stem cell research is
microscopically small and has no nervous system.
Does it count as a “person” who has a right to life?
• What do various religions say about when personhood
begins? Does science have a view on this?
• In a society where citizens hold diverse religious
views, how can we democratically make humane
public policy?
When they divide, each daughter cell has a choice: it can either remain a stem cell or take on a course leading to terminal differentiation.
The job of stem cell is not to carryout differentiation function, but rather to produce cells that will differentiate
CLICK! This diagram will eventually show the entire range of development, from fertilized egg to mature cell types in the body.
Each cell in the 8-cell embryo, here in red, can generate every cell in the embryo as well as the placenta and extra-embryonic tissues. These cells are called CLICK! TOTIPOTENT stem cells. Why are they called totipotent? (wait for answers) Because one red cell can potentially make all necessary tissues for development. CLICK!
During In Vitro Fertilization, can parents choose whether their baby is going to be a boy or a girl? (wait) Yes, there is a widely-practiced procedure called pre-implantation genetic diagnosis, where one cell is removed from the 8-cell embryo and its DNA is examined. What might you look for when trying to identify the embryo’s sex? (wait) If there’s an X and Y chromosome it’s a boy and if there are two X’s it’s a girl. The parents can decide whether to implant it. Also parents with a genetic disease might want to see if their baby has any identifiable genetic disorders and decide whether to implant based on this information. Pre-implantation genetic diagnosis doesn’t destroy the embryo. Scientists are attempting to adapt this pre-implantation genetic diagnosis procedure and use it to create a stem cell line from one single TOTIPOTENT cell, without destroying the embryo.
The embryonic stem cells inside the blastocyst, here in purple, can generate every cell in the body except placenta and extra-embryonic tissues. These are called CLICK! PLURIPOTENT stem cells…why? (wait for answers) Because they can differentiate into all the 200+ cell types in the body, but they do not form the placenta. CLICK! Pluripotent stem cells can be isolated and grown in culture, or left to develop into more specialized cells in the body.
CLICK! Adult stem cells or tissue-specific stem cells have restricted lineages. Adult stem cells show up when the three distinct layers form in the 14-day-old embryo, and are present in the fetus, baby, child, and so forth. Adult just means they’ve gone further down their lineage pathway than the initial stem cells in the embryo. They are called CLICK! MULTIPOTENT stem cells because they will only become mature cells from the tissue in which they reside. Adult stem cells are present throughout your life and replace fully mature CLICK!, yet damaged and dying cells.
So to review (if time): TOTIPOTENT stem cells come from embryos that are less than 3 days old. These cells can make the TOTAL human being because they can form the placenta and all other tissues. PLURIPOTENT stem cells come from embryos that are 5-14 days old. Embryos and fetuses that are older than 14 days DO NOT contain pluripotent cells. These cells can form every cell type in the body but not the placenta. MULTIPOTENT stem cells are also called adult stem cells and these appear in the 14 day old embryo and beyond. At this point these stem cells will continue down certain lineages and CANNOT naturally turn back into pluripotent cells or switch lineages.
Endoderm = inner organs such as digestive, respiratory
Mesoderm = muscles, bone, kidneys
Ectoderm = skin, nervous system
The early stages of embryogenesis are the point at which embryonic stem cell lines are derived. The fertilized egg (day 1) undergoes cell division to form a 2-cell embryo, followed by 4-cell, etc. until a ball of cells is formed by the fourth day. The ball becomes hollow, forming the blastocyst. This is the stage at which pluripotent embryonic stem cell lines are generated. Following the blastocyst stage, the tissues of the embryo start to form and the cells become multipotent.