Submucosa: From 2 Different Sources
The layer of CONNECTIVE TISSUE that occurs under a MUCOUS MEMBRANE – for example, in the intestinal wall.
n. the layer of loose connective (*areolar) tissue underlying a mucous membrane; for example, in the wall of the intestine. —submucosal adj.
These are organized blobs of fats, synthesized in the submucosa of the small intestine out of dietary fats, phospholipids, specialized proteins and cholesterol, carried out of the intestinal tract by the lymph, and slowly released into the bloodstream. In the capillaries, the triglycerides inside the chylomicrons, recognized by their protein markers, are absorbed into the tissues for fuel or storage, and the outside cholesterol and phospholipid transport-cover continues through the blood to be absorbed by the liver for its use. This sideways approach takes (ideally) a large part of dietary fats into the lymph back alleys, spreading their release into the bloodstream out over many hours, thereby avoiding short-term blood fat and liver fat overload. To synthesize the maximum amount of dietary fats into chylomicrons, you need well-organized emulsification and digestion of lipids by the gallbladder and pancreas.... chylomicrons
A hard swelling, or GRANULOMA, characteristic of tertiary SYPHILIS. It normally develops in the skin or subcutaneous tissue, mucous membranes or submucosa, and the long bones. Although often painless, it may produce marked symptoms by interfering with the brain or other internal organs in which it may be located. Treatment with penicillin (or tetracycline if the patient is allergic) usually ensures a rapid disappearance of the gumma.... gumma
Specialized lymph formations found in the small intestine mucosa. Together with enzymatic activities in the submucosa, they collect digested fats into stable transport bubbles called chylomicrons, and draw them up into the lymph system. There they are gradually leeched into the blood as the lymph passes upwards through the body, the remainder discharged into the venous blood with the lymph...12-24 hours later. Time-Released fat capsules. Fats lower the blood charge and make it sticky, which can interfere with vascular capabilities; the sideways bypassing of the blood in this manner spreads the fats out over long periods. The rest of the digested constituents can happily flow up to the liver through the portal system, unsludged, and the liver itself therefore has little lipid stress to face. If fats are poorly digested in the upper intestinal tract, the floating bubbles are larger, broken down too slowly to be well absorbed into the lymph system, and the portal blood...and liver...get sludged. Ever wonder why a bunch of lousy pizza can give you hemorrhoids the next day? Sludgy portal blood and backed-up venous drainage from the legs is why.... lacteals
These are several minute glandular masses embedded in the lower edge of the thyroid gland. They produce Parathyroid Hormone (PTH), part of the calcium-phosphorus control system. Calcium levels in the blood MUST be within a narrow band of safety. If free calcium drops too low, PTH acts on the kidneys and blocks calcium loss in urine, amplifies calcium absorption into the portal blood (from food and from submucosal storage) and stimulates release of calcium from bone storage. When levels are back up, the hormone backs off. Oddly enough, the thyroid gland secretes its virtual antagonist, calcitonin, which, when calcium levels are too high, stimulates the urine excretion, bone retention and digestive resistance to calcium, and when the blood levels drop, recedes. The body finds calcium levels to be so critical that it has in place TWO separate, mutually antagonistic negative feedback systems,,,like a binary star system. (Be thankful I didn’t bring in the calcium maintenance of minerocortical steroid hormones or vasopressin)... parathyroids
Like septicemia, an infection that has moved deeply into the body, involving the subcutaneous or submucosal layers, connective tissue, lymph system...or blood... sepsis
The rash produced by the sudden release of HISTAMINE in the skin. It is characterised by acute itching, redness and wealing which subsides within a few minutes or may persist for a day or more. Depending upon the cause, it may be localised or widespread and transient or constantly recurrent over years. It has many causes.
External injuries to the skin such as the sting of a nettle (‘nettle-rash’) or an insect bite cause histamine release from MAST CELLS in the skin directly. Certain drugs, especially MORPHINE, CODEINE and ASPIRIN, can have the same e?ect. In other cases, histamine release is caused by an allergic mechanism, mediated by ANTIBODIES of the immunoglobulin E (IgE) class – see IMMUNOGLOBULINS. Thus many foods, food additives and drugs (such as PENICILLIN) can cause urticaria. Massive release of histamine may affect mucous membranes – namely the tongue or throat – and can cause HYPOTENSION and anaphylactic shock (see ANAPHYLAXIS) which can occasionally be fatal.
Physical factors can cause urticaria. Heat, exercise and emotional stress may induce a singular pattern with small pinhead weals, but widespread ?ares of ERYTHEMA, activated via the AUTONOMIC NERVOUS SYSTEM (CHOLINERGIC urticaria) may also occur.
Rarely, exposure to cold may have a smiilar e?ect (‘cold urticaria’) and anaphylactic shock following a dive into cold water in winter is occasionally fatal. The diagnosis of cold urticaria can be con?rmed by applying a block of ice to the arm which quickly induces a local weal.
Transient urticaria due to rubbing or even stroking the skin is common in young adults (DERMOGRAPHISM or factitious urticaria). More prolonged deep pressure induces delayed urticaria in other subjects. IgE-mediated urticaria is part of the atopic spectrum (see ATOPY, and SKIN, DISEASES OF – Dermatitis and eczema). Allergy to peanuts is particularly dangerous in young atopic subjects. Notwithstanding the many known causes, chronic urticaria of unknown cause is common and may have an autoimmune basis (see AUTOIMMUNE DISORDERS).
Treatment Causative factors must be removed. Topical therapy is ine?ective except for the use of calamine lotion, which reduces itching by cooling the skin. Oral ANTIHISTAMINES are the mainstay of treatment and are remarkably safe. Rarely, injection of ADRENALINE is needed as emergency treatment of massive urticaria, especially if the tongue and throat are involved, following by a short course of the oral steroid, prednisolone.
Angio-oedema is a variant of urticaria where massive OEDEMA involves subcutaneous tissues rather than the skin. It may have many causes but bee and wasp stings in sensitised subjects are particularly dangerous. There is also a rare hereditary form of angio-oedema. Acute airway obstruction due to submucosal oedema of the tongue or larynx is best treated with immediate intramuscular adrenaline and antihistamine. Rarely, TRACHEOSTOMY may be life-saving. Patients who have had two or more episodes can be taught self-injection with a preloaded adrenaline syringe.... urticaria
compound glands of the small intestine, found in the *duodenum and the upper part of the jejunum. They are embedded in the submucosa and secrete mucus. [J. C. Brunner (1856–1927), Swiss anatomist]... brunner’s glands
(leather-bottle stomach) diffuse infiltration of the stomach submucosa with malignant tissue, producing rigidity, narrowing, and reduced luminal capacity. Endoscopic diagnosis may be difficult (typically the stomach does not distend during air insufflation at gastroscopy) but radiological changes are more marked.... linitis plastica
n. the endoscopic or surgical removal of a *polyp. The technique used depends upon the site and size of the polyp. Endoscopically, polyps can be removed by various methods. A hot biopsy involves coagulation of a small polyp using a diathermy current passed through biopsy forceps, which obtains a sample for analysis at the same time. Cold biopsy involves removal of a polyp using forceps alone, thereby decreasing the perforation risk. Snare polypectomy uses a wire loop (snare) to cut through the base of the polyp. This is performed with or without a diathermy current (hot snare vs. cold snare); the current reduces the risk of bleeding by coagulating local blood vessels as the snare cuts through the polyp. Endoscopic mucosal resection (EMR) involves lifting a flat polyp by injecting a hypertonic solution into the submucosa beneath the polyp followed by snare polypectomy with diathermy. Nasal polyps may be removed using *endoscopic sinus surgery techniques, sometimes utilizing a *microdebrider.... polypectomy