nature (March 15, 2023) – Lymphocytes are immune cells that play vital roles in fighting infections. The most well-known lymphocytes are the T cells and B cells of the adaptive immune system. In the 1950s and 1960s, scientists performed experiments to follow lymphocytes on their journey around the body, which helped us to work out where they go and what they do.
This work laid the foundation for everything we know about T cells today, including how they become activated to fight infections and how they form memory populations that provide long-lasting immunity.
Lymphoma is a cancer of the lymphatic system – our body’s immune system. The two main types of lymphoma are Hodgkin and non-Hodgkin. In this video, we break down how both types of lymphoma begin and the differences between them.
Chapters: 0:00 Intro 0:15 What are lymph nodes? 0:40 What is a cell mutation? 0:52 What is lymphoma? 1:15 What is the difference between Hodgkin and Non-Hodgkin lymphoma? 1:28 What are common symptoms of lymphoma?
The pulmonary circuit oxygenates and the systemic arterial circuit circulates several Liters of blood per minute. As this blood trickles through the capillaries, some of it oozes out through the thin endothelial lining, becoming interstitial fluid.
Most of this flud gets back into the capillaries and returns to the heart in the venous return. About 20% of the fluid drains into the LYMPHATIC SYSTEM, through the Lymph nodes, and back into the thoracic duct, into the vena cava, and eventually back into the general blood supply, which recirculates.
The Return of the residual interstitial fluid by the Lymphatic vessels back to the general circulation is important, and if BLOCKED by such things as surgery and parasites, produces a swelling known as LYMPHEDEMA.
But the major importance of the lymphatic vessels is their characteristic cells, LYMPHOCYTES, and their accessory structures, The THYMUS, SPLEEN, LYMPH NODES, AND LYMPHATIC TISSUES is in the development and training of the IMMUNE SYSTEM. The THYMUS can be regarded as an organ to TRAIN Lymphocytes to be functional members of the immune system.
SomeT-cells operate to Help B-cells to produce antibody. These are called Th-4 cells. Others, called Th-8 cells. function to delete cells,
The thymus POSITIVELY selects cells that are prepared to recognize pathogens, and gets rid of cells (NEGATIVELY selects) cells that recognize the body’s own cells.
Failure to do so would result in “horror autotoxicus”, or AUTOIMMUNITY. The Thymus performs most of its functions when we are young.
The LYMPH NODES act as a type of filter for the Lymphatic channels, and intercept most bacteria and other pathogens coming through the lymphatic channes to keep them out of the blood stream. Lymph nodes are present at predictable locations throughout the body.
The Spleen acts as a big lymph node to filter the blood directly, and can intercept organisms that have escaped the lymph nodes. The Spleen can enlarge with certain infections, as with the EB Virus that causes mononucleosis.
Rupture of the spleen is not uncommon with direct blunt trauma to the abdomen. Removal of the spleen can increase susceptibility to blood stream infection. Lymph tissue is scattered throughout the body, like in the Tonsils, adenoids and Intestinal tract.
This Lymphocyte-containing tissue can expand with exposure to infection, and can become cancerous with Lymphomas. It can also enlarge enough to produce local Blockage, as with Adenoids. Lymph tissue should not be removed wantonly, since it may provide protection. There are 2 arms of our immune system.
I have been discussing the ADAPTIVE immune system which recognizes the pathogen, and stores memory of this interaction in “memory T-cells”. The helper T-cells( Th-4) start to multiply and stimulate the B-cells to “clonally” proliferate and differentiate into Antibody-producing Plasma Cells. The Cytotoxic T-cells, which can directly kill Pathogens, also multiply.
The first time this happens with a new Pathogen, Like SARS CoV-2, this adaptive process takes a week or so. But if the same Pathogen comes later, The adaptive immune system is ready, via the Memory T-cells, and springs rapidly into action. The 2nd arm of our immune system, shared with all of our vertebrate relatives, is the INNATE immune system.
The innate system is prepared IMMEDIATELY to recognize certain foreign molecules common to many invaders, and foreign our own bodies. It usually does not have the Power of the innate immune system, but in healthy people does an amazingly good job.
Some people just don’t get sick very often. Do the best you can to be one of these healthy people by getting proper SLEEP, DIET. AND EXERCISE!
BLOOD VESSELS; it is hard to overestimate their importance. They are literally our lifelines, delivering the oxygen and nutrition necessary for life. We are as old as our blood vessels.
I will divide blood vessels into 4 components with rather separate domains: The Systemic Arterial system, the Pulmonary circulation, the Venous system, and the Lymphatic system, and will discuss these separately.
SYSTEMIC ARTERIAL SYSTEM
The Boy Scouts taught me the pressure points; The radial, at the thumb-side of the wrist, the brachial, on the inside of the upper arm, and the inguinal in the groin area. Pressure on these sites will stop arterial bleeding distally.
You should be able to locate the radial artery pulse, and begin to appreciate its strength and regularity. Strength in case you encounter a person who isn’t moving, and regularity for yourself; many older people develop an irregularity called Atrial Fibrillation, and you might be the first to discover it..
ANEURISMS are swelling of the arteries, and the swelling may thin the arterial wall so that it can burst. A Cerebral aneurysm can burst and cause a stroke-like problem. If an aortic aneurism bursts, the internal blood loss can be fatal.
RAYNAUD’S Phenomenon is fairly common, and consists of an over-reaction to cold, where arteries of the hands constrict, and the fingers get white and cold. Burger’s disease involves small arteries, and often is associated with Raynaud’s. The arteries carry the blood distally (away from the heart), continuing to divide into ever smaller arterioles which terminate in capillaries, which branch out in such an arborization as to supply all cells except cartilage and parts of the eye.
HYPERTENSION develops when the arterioles, under hormonal or neural influence, constrict, increasing the resistance to blood flow, and so the pressure. Increase in sodium retention and therefore the blood volume can also increase pressure.
ATHEROSCLEROSIS is the common disease of western life style. Excessive calories and sedentary life style combined with genetic defects in fatty metabolism produce cholesterol plaques which narrow and stiffen the arteries, often leading to BLOCKAGE of blood flow. Blockage of flow to the HEART, BRAIN, KIDNEYS, BOWEL, or EXTREMITIES each produce their separate disorders of Myocardial Infarction, Stroke, Renal artery Disease. Intestinal ischemic syndrome, and Claudication.
These disorders will each be separately discussed. I have always thought of vascular disease as a special class of CAUSATIVE MECHANISMS when trying to develop a DIFFERENTIAL DIAGNOSIS of a patient’s problems. Blockage to an area results in PAIN or LOSS OF FUNCTION.
Stroke is usually painless with blockage, since the brain has no pain sensors. Blockage of the renal artery often causes complex difficulties including Hypertension, because the kidney is an endocrine organ in addition to its excretory function.
A good Friend and patient showed what careful self-care can accomplish. It all started with a myocardial infarction, the first sign of his blood vessel disease. He had a complication in his workup, and had to have emergency bypass surgery. There had been damage to the heart muscle, with a large reduction in his EJECTION FRACTION.
His cardiologist gave him at most 5 years to live. That was 25 years ago, before the development of the statin drugs. He was given a draconian low cholesterol diet, which he followed exactly. One one visit to the cardiologist, he inquired whether he could have other areas of arterial blockage. His doctor then listened to his neck and discovered a bruit (noise) in the carotid artery, after which he had a Carotid endarterectomy.
In an orthopedist office for back pain, the orthopedist left the room, and my friend noticed in the CT scan report mention of cysts in the kidneys.
The Orthopedist cared mainly about his bones, and had overlooked the “incidental finding”. His brother had died of mesenteric artery blockage from atherosclerosis, he had stomach symptoms, and sure enough he also had arterial blockage to the intestines.
Bottom line: it pays to be an ACTIVE PARTICIPANT in our medical treatment, and even though we all have genetic determinants, we can make our health BETTER with attention to our health, especially SLEEP, DIET and EXERCISE.
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