This document provides an overview of the cardiovascular system. It discusses the main functions of the circulatory system including transporting essential substances and removing metabolic byproducts. It describes the two main divisions of the system - the pulmonary and systemic circuits. It also discusses the structure and function of the heart, blood vessels including arteries, veins, and capillaries, as well as sensory receptors in arteries that monitor blood pressure and chemistry.
11.03.08(c): Histology of the Cardiovascular SystemOpen.Michigan
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Learning Objectives:
Compare and contrast the structure and function
of
Arteries
Veins
Capillaries
ulatory
system
Arteries
Arterioles
Capillaries
Venules
Veins
3 tunics
Lume
The Vessels
Functions:
Distribution of blood
Exchange of materials with tissues
Return of blood to the heart
Structure:
Most have the same basic structure:
– 3 layers surrounding a hollow lumen
11.03.08(c): Histology of the Cardiovascular SystemOpen.Michigan
Slideshow is from the University of Michigan Medical School's M1 Cardiovascular / Respiratory sequence
View additional course materials on Open.Michigan:
openmi.ch/med-M1Cardio
Learning Objectives:
Compare and contrast the structure and function
of
Arteries
Veins
Capillaries
ulatory
system
Arteries
Arterioles
Capillaries
Venules
Veins
3 tunics
Lume
The Vessels
Functions:
Distribution of blood
Exchange of materials with tissues
Return of blood to the heart
Structure:
Most have the same basic structure:
– 3 layers surrounding a hollow lumen
Medical conditions that can directly affect the provision of dental care and/...Ruhi Kashmiri
Medical conditions that can directly affect the provision of dental care and/or consequences of dental treatment. In paediatric dentistry, such children are known as children with special needs and require extra attention for maintainence of optimum oral health.
Guidelines for writing an impressive CV (resume) for applying for a job in the IT industry. Important topics discussed:
What Is a Resume?
Why We Need of a Resume?
Why We Need a Good Resume?
The Goal of a Resume
Success strategy in writing a CV
How to Stand Out?
Structure of a Typical Resume (CV)
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The first topic in the practical histology coarse for pharmacy students
In this lecture the student will be able to recognize the histological layers of the circulatory system parts such as veins and arteries and the similarities and differences between each layer
The circulatory system transports fluids throughout the body;
it consists of the cardiovascular and lymphatic systems.
The heart and blood vessels make up the blood transportation network, the cardiovascular system.
Through this system, the heart pumps blood through the body’s vast system of blood vessels.
The blood carries nutrients, oxygen, and waste products to and from the cells.
VASCULAR CIRCUITS
The heart consists of two muscular pumps dividing the circulation into two components:
pulmonary circulations
systemic circulations or circuit
Pulmonary Circulation
Rt ventricle propels low O2 blood into the lungs via the pulmonary arteries.
CO2 is exchanged for O2 in the capillaries of the lungs.
Then the O2 -rich blood is returned via the pulmonary veins to the Lft atrium.
This circuit, from the right ventricle through the lungs to the left atrium, is the pulmonary circulation.
Systemic Circulation
Left ventricle propels the O2 -rich blood through systemic arteries (the aorta and its branches),
exchanging O2 and nutrients for CO2 in the remainder of the body’s capillaries.
Low- O2 blood returns to right atrium via systemic veins (tributaries of the superior and inferior vena cava).
This circuit, from left ventricle to right atrium, is the systemic circulation.
Arteries are blood vessels that carry blood away from the heart. This blood is normally oxygenated, exceptions made for the pulmonary and umbilical arteries
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
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.
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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.
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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
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
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Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
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.
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
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
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.
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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.
1. Cardiovascular system
overview
Presented 2011 / 2012 by: Dr Magdi El Sersi
Assistant Prof of Medical Physiology
Basic Medical Sciences Department
Ext. 7243
E mail:
melsersi@sharjah.ac.ae
2. •Feel free to make notes, but don’t
try and copy everything I show and
say – you won’t have time. I would
rather prefer that you just listen.
•If you have a question please catch
my attention – I am more than happy Profile
to stop; or you can pass by my office
at M27-Room 123. Silent
•The recommended course
textbooks cover my lectures well.
•If you need a copy of this
presentation, then you can get it
from the blackboard.
3.
4. MAIN FUNCTIONS OF THE
CIRCULATORY SYSTEM
• Transport and distribute essential substances
to the tissues.
• Remove metabolic byproducts.
• Adjustment of oxygen and nutrient supply
in different physiologic states.
• Regulation of body temperature.
5. The system has two major
divisions:
v A pulmonary circuit :
which carried blood to the
lungs for gas exchange and
returns it to the heart.
v A systemic circuit :
which supplies blood to
every organ of the body.
6. The right
side of the
heart serves
the The left side
pulmonary serves the
circuit systemic
circuit.
7. The heart is enclosed in a
double-walled sac called the
pericardium.
The outer wall,
called the parietal
pericardium
(pericardial sac).
has a tough, superficial fibrous layer of dense
irregular connective tissue and a deep, thin
serous layer.
The serous layer turns inward at the base of the
heart and forms the visceral pericardium (epicardium)
covering the heart surface .
8. The pericardium
The pericardial sac is anchored by ligaments to the
diaphragm below and the sternum anterior to it.
Between the parietal and visceral membranes
is a space called the pericardial cavity . It
contains 5 to 30 mL of pericardial fluid.
9. The pericardial fluid Pathophysiology : Pericardial
lubricates the membranes disease manifest itself by the
and allows the heart to accumulation of fluid in the
beat almost without pericardial space (pericardial
friction. effusion) and /or inflammation
of the pericardium (pericarditis).
The pericardial cavity can fill with up to
2 litters of serous fluid
(hydropericardium ) or blood
(hemopericardium) that prevent
normal diastolic filling and thereby
reduces cardiac output.
10. COLLECTING
PUMP TUBULES
THE MAIN CIRCUIT
DISTRIBUTING THIN
TUBULES VESSELS
11. There are 3 primary blood vessel
types:
1. Arteries : which carry blood
away from the heart.
2. Veins : which carry blood
towards the heart.
3. Capillaries : tiny blood
vessels that function in the
exchange of gases, nutrients,
and wastes between the blood
and the interstitial fluid.
12. The walls of both arteries and veins have 3
layers that surround the lumen:
1. Tunica externa
Outermost layer. Made primarily of loose
connective tissue. Anchors the blood
vessel to the surrounding tissue.
2. Tunica Media
Consists primarily of smooth muscle and
is responsible for vasoconstriction and
vasodilatation. Usually the thickest layer
in arteries.
3. Tunica Interna (Endothelium) Acts as a
selectively permeable barrier to blood
solutes.
Secretes vasoconstrictors and
vasodilators.
Provides a smooth surface that repels
blood cells and platelets.
13. They are constructed to withstand
surges of blood pressure associated with
ventricular systole.
•They're more muscular than veins and appear
relatively round in tissue sections.
• They retain their round shape even when empty.
There are 3 basic categories of arteries
15. 1. Conducting (or Elastic) Arteries
The largest
Examples include the aorta, pulmonary arteries,
and the common carotid arteries.
16. Their tunica media contains a
great deal of elastic tissue.
The elastic tissue allows for
expansion during ventricular
systole and recoil during
ventricular diastole.
This helps create continuous
flow from a discontinuous
pump.
17. Conducting arteries expand during ventricular systole to
receive blood, and recoil during diastole:
*Their expansion takes some of the pressure off the blood so that
smaller arteries downstream are subjected to less systolic stress .
•* Their recoil between heart beats prevents t he blood
pressure from dropping too low while the heart is relaxing
and refilling.
Lessen the fluctuations in blood pressure
18. 2. Distributing (or Muscular) Arteries
Smaller branches ,distribute blood to individual organs.
They have 25-40 layers of smooth muscle cells
constituting about three quarters of the wall thickness.
Examples include the brachial, femoral, and splenic arteries
19. 3. Arterioles
•Smallest of the three.
• They are heavily innervated .
• The primary points at which the body controls the
relative amounts of blood directed to specific organs.
20. Linking the arterioles
to the capillaries are
short vessels known
as metarterioles.
Part of their wall surrounded
by smooth muscle
These muscle cells form precapillary sphincters which
encircle the entrance to a capillary bed.
22. Arterial sense organs:
Certain major arteries above
the heart have sensory
structures in their walls that
monitor blood pressure and
chemistry.
They transmit information to
the brain stem that is used to
regulate the heart beat,
vasomotion and respiration.
23. The sensory receptors are of three kinds
1. Carotid sinuses. These are
baroreceptors (pressure sensors) that
respond to changes in blood pressure.
* Thin tunica media
* An abundance of glossopharyngeal
nerve fibers in the tunica externa.
A rise in blood pressure stretches the
thin media and stimulates the nerve
fibers which transmits signals to the
The carotid sinuses vasomotor and cardiac centers of the
are located in the brainstem, which responds by lowering
wall of the internal the heart rate and dilating the blood
carotid artery vessels, thereby lowering the blood
pressure.
24. 2. Carotid bodies: located near the
branch of the common carotid
arteries.
They are chemoreceptors
that monitor changes in
blood composition.
They primarily transmit
signals to the brainstem
respiratory centers, which
adjust breathing to stabilize
the blood pH and its CO2 and
O2 levels
25. 3. Aortic bodies: These are one
to three chemoreceptors
located in the aortic
arch
They are structurally similar to
the carotid bodies and have
the same function.
26. Capillaries
There are approximately 1 billion of them in the human body.
Capillaries are organized into groups of 10-100 in capillary beds
There are 3 separate types of capillaries:
1. Continuous Capillaries
2. Fenestrated Capillaries
3. Sinusoidal Capillaries
27. 1. Continuous Capillaries Most common.
Abundant in skin and muscle.
Endothelial cells are joined by tight junctions.
but contain intercellular clefts through which small molecules
(e.g., glucose, but not albumin) can pass.
Cerebral capillaries lack these clefts and have far more
numerous tight junctions forming the blood brain barrier which
helps protect the delicate brain tissue from blood-borne toxins
and pathogens.
28. Some continues capillaries
exhibit cells called pericytes
that lie external to the
endothelium
Pericytes are contractile,
have elongated tendrils that
wrap around the capillary
It thought that they contract and regulate blood flow
through the capillaries.
They also can differentiate into endothelial and smooth
muscle cells and thus contribute to vessel growth and
repair.
29. 2. Fenestrated capillaries
These pores allow for
the rapid passage of
molecules, even
proteins , through the
capillary wall.
Found in sites of active
Similar to absorption (small intestine),
continuous secretion (endocrine
capillaries but organs) and capillary
some of the filtration (kidneys).
endothelial cells
has filtration pores
fenestrations.
30. 3. Sinusoidal Capillaries
Highly modified, extremely
leaky, fenestrated capillaries
Contain irregularly shaped lumen and large intercellular clefts
Found in sites where large stuff needs to
exit/enter the bloodstream.
Such sites include bone marrow (for
passage of nascent blood cells), lymphoid
organs (for easy entry/exit by WBCs) and
the liver (for large plasma proteins, e.g.,
albumin).
31. In the liver and the spleen , the
endothelium is intimately
associated with macrophages.
In these locations the sinusoids
are twisty and tortuous,
conformed to the shape of the
surrounding tissue. . The
twistiness makes blood flow
extra slowly which gives time
for splenic and hepatic
macrophages to monitor and
assess its contents.
32. Just by looking at this image, can you identify the
different capillary types?
33. Veins
The capacitance vessels of the cardiovascular system
because :
They are relatively thin-walled and flaccid.
Expand easily to accommodate an
increased volume of blood.
At rest, about 54% of
the blood is found in
the systemic veins as
compared with only
11% in the systemic
arteries
34. Being distant from the ventricles of the heart,
they are subjected to relatively low blood
pressure.
In large arteries, blood pressure averages 90 to
100 mm Hg (millimeters of mercury) and
surges to 120 mm Hg during systole, whereas
in veins it averages about 10 mm Hg.
Considering the relatively low pressure in
the veins.
how blood is forced through them to get back to the
heart????
35. It's a combination of 3 separate things:
1.Skeletal Muscle Pump .
2. Respiratory Pump .
3. Venous Valves
36. It's a combination of 3 separate
things:
1.Skeletal Muscle Pump .
2. Respiratory Pump .
3. Venous Valves
1. Skeletal Muscle
Pump :- the
contraction/relaxation
cycles of skeletal
muscles squeeze the
veins forcing the
contained blood
towards the heart.
37. 2. Respiratory Pump : as we inhale,
our thoracic cavity expands while
our abdominal cavity compresses.
pressure within veins of the
thoracic cavity drops.
Meanwhile, pressure in the
abdominal veins increases.
This combination results in
increased blood flow towards that
heart.
38. 3. Venous Valves: - one-way
valves (similar to the
semilunars of the heart) made
of flaps of endothelium are
found in medium veins
(mostly in the legs and the
arms) where they help prevent
backflow.
39. Pathophysiology: varicose
veins:
In people who stand for long
periods, blood tends to pool in the
lower limbs and stretch the veins.
This is especially true of superficial
veins, which are not surrounded by
supportive tissue.
Stretching pulls the cusps of the
venous valves farther apart until the
valves become incompetent to
prevent the backflow of blood
40. As the veins become further
distended, their walls grow
weak and they develop into
varicose veins with irregular
dilations and twisted pathways.