PATIENT EDUCATION: THE “2020 WEEKLY CROSSWORD PUZZLE CHALLENGE” (JUL 26)
Category Archives: Resources
BLOOD CIRCULATION: THE “LYMPHATIC SYSTEM”
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!
INFOGRAPHICS: “HOW TO ACHIEVE YOUR WEEKLY RECOMMENDED EXERCISE”
COMMENTARY
The idea of “METS” as a unit of energy expenditure is interesting and practical. I agree that EXERCISE IS IMPORTANT.
Frank Wilczek, in an article on Dyson Freeman, talked about another unit that I find even more interesting . He proposed that 100 Watts be the unit of energy expenditure. This is (approximately) the energy used in an old 100 Watt incandescent light bulb. It is also the amount of energy used by the “average” human on a 2000 Calorie diet.
Using this unit, the average U.S. Citizen uses 95 units, compared to a 25 unit world average. The suns output is 5 X ten to the fourteenth power, of which 1X ten to the fourth power units lands on earth. Good cocktail information.
I also read that a professional cyclist has an output of only 400 watts, vs. the 14 Mets mentioned in the article.but when I read that the human body is only 20-25% efficient in converting Calories to Watts of Output, 14 Mets made more sense.
—Dr. C.
PATIENT EDUCATION: THE “2020 WEEKLY CROSSWORD PUZZLE CHALLENGE” (JUL 19)
PATIENT EDUCATION: THE “2020 WEEKLY CROSSWORD PUZZLE CHALLENGE” (JUL 12)
MEDICAL INFOGRAPHIC: “ANTIMICROBIAL RESISTANCE”
PATIENT EDUCATION: THE “2020 WEEKLY CROSSWORD PUZZLE CHALLENGE” (July 3)
PATIENT EDUCATION: THE “2020 WEEKLY CROSSWORD PUZZLE CHALLENGE” (Jun 29)
THE DOCTORS 101 CHRONIC SYMPTOMS & CONDITIONS #4: HEARTBURN (ACID REFLUX)
I have been having Heartburn for more than 40 years. The cause of Heartburn is leakage of acid from the stomach, where tissues have evolved to tolerate the highly acidic conditions, into the esophagus, where they haven’t.
The young body has an efficient, functional gate, or sphincter, keeping the food, once swallowed into the stomach, from coming back up. As you eat, you chew your food well to aid digestion. Your taste buds, sensing chemicals in the delicious food, activate saliva.
The salivary enzymes start the digestion of the carbohydrates in the food. If you eat slowly enough, you may be able to appreciate the digestion of tasteless starch, like in bread, into sweet sugar, right in your mouth.
You then swallow the food, which slips past another gate, called the epiglottis, diverting the bolus of food past your windpipe. This gate sometimes does not shut tight, and you choke on the food or drink. The food is then conducted into the highly acidic environment of the stomach.
The stomach evolved to be an acidic, “fiery pit”, inhospitable to any bacteria that came in with the food, thus protecting the stomach from infection. In the old days, there were a lot of bacteria, and the acidity of the stomach was useful, and evolutionarily conserved.
These days, the “fiery pit” tends to be a problem. As you get older, the gate that keeps food in the stomach gets more floppy and relaxed, and allows food to come back up into the esophagus, and sometimes, most often at night when you would rather be sleeping, all the way up to your throat, and is inhaled into your windpipe and lungs in what is called “gastroesophageal reflux”, or GERD.
Even if the food, and acid, doesn’t make it all the way up, and stops at the esophagus, which has not evolved to tolerate acid, you will have “heart burn”. Of course it is not the heart that is burning, but the esophagus, which runs right past the back of the heart as it goes all the way from the throat to the stomach.
When I first developed Heartburn, all that was available was the flavored chalk, Calcium Carbonate, sold as Tums. It works right away, and is a source of Calcium, but can cause trouble, like kidney stones, if you take too much. The relief didn’t last long enough for me, and I had to take more in the middle of the night.
My next medicine was Xantac, a medication that blocks histamine from stimulating acid production in the stomach. The H2 blockers have recently been recalled because of NDMA contamination. I sometimes used H2 blockers like Xantac when my patients would get a bad allergic reaction. In such cases BOTH an H1 blocker like Benadryl, and an H2 blocker are called for.
Zantac was not strong enough for me, and I soon graduated to Prilosec,which directly blocks the secretion of acid in the stomach.
Prilosec was then very expensive, but now is available as the inexpensive GENERIC Medication, Omeprazole. It seems that no medication is without side effects.
Omeprazole, by reducing stomach acid, makes stomach and GI infections more likely, and interferes with the absorption of B12, and Calcium.
If you have had a lot of heartburn over a long period of time, you should check with a Gastroenterologist, who may scope you to rule out Barritt’s esophagus, which can lead to Cancer.
It is interesting that the antacid Tums in excess can cause too MUCH Calcium in the body, and can cause kidney stones and other kidney problems like MAS, and Omeprazole, by interfering with absorption can cause too LITTLE absorption of Calcium, leading to OSTEOPOROSIS.
The best rule is to take as low a dose of ANY medication as possible, preferably none, to understand the possible side effects, and compensate for them if you can.
Doctors Without Waiting Rooms 