Tomorrow is the Chinese New Year. According to the national custom, it is inevitable to eat and drink. Eating and drinking can injure one of the body’s organs. This organ is the stomach. Zhou Menghan, Department of Orthopedics, The Fifth Affiliated Hospital of Xinjiang Medical University
What is the structure of the stomach?
The stomach is a pocket-shaped tube. The upper part is connected to the esophagus and the lower part to the duodenum. The middle expands into a cone-like curved tube with a large top and a small bottom. When the body is upright, the upper wall of the stomach is called the lesser curvature of the stomach and the lower wall is called the greater curvature of the stomach. The wall of the stomach on the side of the greater curvature is longer than that on the side of the lesser curvature. Why is this? This is the gradual formation of food fall pull.
The upper mouth of the stomach connects to the esophagus. The upper part of the greater curvature of the stomach extends continuously with the esophagus in an enlarged area called the fundus. The lower mouth of the stomach is called the pylorus, which is connected to the duodenum. The pylorus is different from the cardia, which is very short and has a relatively relaxed circular sphincter. The pylorus is a conical section of duct with a thicker muscular wall. Therefore, the pylorus has a higher ability to control the passage of food than the cardia. The portion from the fundus to the pylorus is called the body of the stomach. The body of the stomach is long on one side (the greater curvature) and short on the other (the lesser curvature).
The stomach wall, like the rest of the digestive tract, is in four layers. From the lumen outward, the innermost layer is the mucosa. Beyond the mucosa is the submucosa. Beyond that is the base layer. The outermost layer is the plasma membrane layer.
The mucosa of the stomach wall has two main types of secretory cells. One type secretes mucus, called mucous cells. One secretes gastric acid, called mural cells. Next, there are the main cells that secrete gastric enzymes and the endocrine cells. There is also an undifferentiated cell that cannot be named (meaning that this cell can form a cancer, which is a bit of a stretch. It’s actually a small scar).
The secretion of all the cells of the gastric mucosa combined is the gastric juice.
The muscle layer of the stomach is a sphincter that is tightly packed on the small curvature side and loosely fan-shaped on the large curvature side. It contracts in the same way as the rest of the digestive tract, with passive extension followed by active contraction. It is controlled by gastric contents and vegetative nerves.
The plasma membrane is the protective membrane for gastric peristalsis and is part of the peritoneum. The surface is lined with plasma, which keeps the outer wall of the stomach smooth. It reduces frictional damage during gastric peristalsis.
What controls the peristalsis of the stomach?
The peristalsis of the stomach is controlled by the vegetative nerves. Humans are vertebrates. The internal organs of all vertebrates are controlled by the vegetative nerves. The stomach is no exception. In addition to the passive expansion and contraction caused by the volume of food, it is also controlled by the rhythm of its contraction by the vegetative nerves. There are two types of vegetative nerves: sympathetic and parasympathetic. Sympathetic nerves are easily influenced by the brain. The parasympathetic nerves are generally not influenced by the brain. Sympathetic nerves inhibit the contraction of the digestive tract, while parasympathetic nerves excite the contraction and secretion of the digestive tract. Therefore, when the brain is excited, sympathetic nerves influenced by the brain can reduce the frequency of gastric contractions and slow down the emptying of the stomach. At night, when the brain is resting, sympathetic nerves are inhibited and parasympathetic nerves are relatively excited, and the peristaltic force and frequency of contraction and secretion of gastric juice are increased compared to daytime.
What is the function (role) of the stomach?
Based on the previous structure, we know that the stomach acts to receive food sent down from the esophagus and deliver it to the duodenum. In this process, the stomach, through its anterior loosening and posterior tightening (cardia loosening and pylorus tightening) structure, allows food to be retained, stirred into a paste with gastric juice by propulsive peristalsis, and then transported to the duodenum. The role of gastric juice is to soak the food and to crush the food vermicelli. The oral cavity crushes food as a rough process, while gastric juice crushes food as a fine process. The digestive tract after the stomach has no further role in crushing food.
The shape of the pylorus is a conical tube with a wide head and narrow tail, which is easy to pass through the liquid, while large solids are not easy to pass through and will be blocked at the upper mouth of the pylorus, or even squeezed back into the body of the stomach through peristalsis to crush again.
Thus, the stomach is a pocket with a stirring function, which is propelled by peristalsis to soak and knead the food, which is called digestion.
What is hunger?
After the stomach is emptied of food, there is only gastric juice in the stomach. Gastric juice is acidic. The main component of gastric acid is hydrochloric acid. ph value is between about 1 and 2, and its concentration is equivalent to 0.036-0.36 g of hydrochloric acid in 100 ml of gastric juice. Although the acidity is lower than that of concentrated hydrochloric acid, the stomach lining can still be burned by the acid corrosion. The stomach lining is burned by the acid and peristalsis is accelerated to get rid of the gastric acid. Therefore, the painful sensation when the stomach mucosa is burned very superficially is the hunger sensation.
Hunger is actually also a type of stomach pain. Eating dilutes and reduces the acidity of the gastric juice. It reduces the irritation of stomach acid on the stomach lining.
What is the role of gastric juice?
Gastric juice is a double-edged sword that can both soak and corrode food and damage the mucous membrane of the stomach lining. The corrosive nature of gastric acid has the effect of protecting the body from microorganisms and can kill them.
What is superficial gastritis?
Food that is coarsely crushed by the mouth enters the stomach cavity, and under the peristaltic kneading of the stomach, the hard food can scratch or abrade the stomach wall. The part that is scratched is covered only by a new mucous membrane, which becomes congested, bleeding and edematous when stimulated by gastric acid. This is superficial gastritis. The gastric mucosa will be repaired quickly by a liquid, fatty or starchy diet that dilutes the stomach acid and removes the irritation.
What is a gastric ulcer?
A gastric ulcer occurs when the mucous membrane at the site of damage is shed and the submucosa is exposed after damage to the stomach wall. Unlike gastric ulcer and gastritis, the repaired stomach wall has no mucous membrane, only submucosal fibrous scarring. There is no function of secretion. Therefore, it is easily re-injured.
What are the causes of gastric ulcers?
In terms of gastric wall damage, all causes of damage to the stomach wall are possible causes of gastric ulcers.
1 Scratches from hard food. Hard food that is not corroded by stomach acid can bruise and scratch the stomach wall under stomach squeezing and rubbing, and if the damage exceeds the mucosal layer, a hard-to-heal ulcer is to be formed.
2 overexpansion of the stomach cavity (overeating), is one of the causes of stomach wall damage. The stomach cavity is filled with excessive food, the stomach wall is stretched and thinned, and the blood vessels of the stomach wall are squeezed, forming ischemia, necrosis, and shedding of the mucosal layer of the stomach wall to form ulcers.
3 Stomach acid stimulation for a long time. The exposed stomach wall is not healed after a long time under the stimulation of acid.
4 In a state of high brain excitement (so-called stress state), sympathetic nerves inhibit the peristaltic frequency of the digestive tract, slowing down the emptying for the contents, leading to the retention of gastric acid and erosion of the scratched gastric mucosa.
5 In states such as burns and coma (there is a so-called stress state), the parasympathetic nerves are excited and gastric peristalsis and secretion are relatively enhanced, leading to erosion of the once gastric mucosa by gastric acid and the formation of ulcers due to the absence of feeding.
6 The massive use of glucocorticoids (immunosuppressants) can inhibit the repair of the damage that already exists and form ulcers.
The latter three are the so-called stress ulcers. It is actually the same thing, that is, to aggravate the damage on top of the existing damage.
Can H. pylori cause ulcers?
H. pylori is nothing more than a parasitic bacterium in the upper gastrointestinal tract that likes acidity and aversion to alkali, and therefore can survive in the stomach. Its attraction to the mucosa is not enough to damage it, so it does not cause ulcers. However, its adsorption to the ulcer surface can damage and delay the healing of the ulcer.
Occurrence of gastric cancer
There are many causes of gastric cancer, but none of them can stand the scrutiny. Personally, I think there is only one cause of stomach cancer – viral infection.
If the stomach wall is damaged to the submucosa, the gap in the wall will be filled by the fibrous connective tissue in the submucosa. If the new fibrous connective tissue is infected by the virus and appears to grow excessively irregularly, this is gastric cancer. Similar to this is a wart – a wart on the skin.
All injuries deep into the submucosa of the stomach wall are usually filled with fibrous connective tissue. In the human body, only fibrous connective tissue maintains the ability to reproduce vigorously. This capacity is genetically controlled. Viruses can be involved in altering the genetic structure, resulting in disordered tissue growth. There are inflammatory overbands between normal and cancerous tissues. The transitional zone is wrapped with near normal inflammatory tissue, and usually pathological sections that are cut to this part will conclude that it is highly differentiated. Cutting to the tumor proper may again lead to a conclusion of hypofractionation. Pathology is a microscopic world, and there can be a world of difference between specimen sampling and macroscopy. The level of differentiation of the tissue depends on the amount of normal or near-normal tissue components wrapped around the body. The same is true for the treatment of histochemistry.
One of the reasons for the formation of gastric cancer is that overeating and binge eating in young age damaged the mucosa of gastric wall forming a scarred gastric wall without mucosa, which is easily re-injured. One is the decrease in glandular secretion and lowered gastric acid. One is the decrease of immunity. The final key is that the wound is infected with a specific virus. These links combine together to form gastric cancer. This is why gastric cancer is mostly seen in the elderly and those with low stomach acid.
There used to be two types of gastritis (actually just one, differing only in the outcome of injury and recovery) – atrophic gastritis and hypertrophic gastritis. Atrophic gastritis is actually the replacement of a large portion of the mucosa of the stomach wall with scarring. Hypertrophic gastritis is mucosal edema with no damage to the mucosa. Because of the protection of the mucosal layer, patients with hypertrophic gastritis are less likely to develop gastric cancer.
I remember the pathology class when I was in school, it was said that Lin County is a high incidence area for esophageal and gastric cancer, and after the flow of investigation, it was said that people there eat more sauerkraut, and it was said that sauerkraut is rich in nitrite. Often three generations of grandchildren in the family suffer from the same cancer. This leads to the fallacy that sauerkraut causes cancer and is hereditary in families. In fact, sauerkraut can be preserved for a long time because it is rich in nitrite. At best, nitrite causes systemic vascular poisoning and has nothing to do with cancer. The reason why people there are prone to esophageal and stomach cancer. It is because there are a large number of carcinogenic virus carriers among the people there and close contact in the family. Mutual transmission.
Why is the site of stomach cancer mostly in the fundus and the lesser curvature of the stomach?
The virus is acid-fearing, and the fundus and the lesser curvature are relatively high in the upright position on an empty stomach, so there is less contact with the gastric juice and the greater curvature. Therefore, it is easy to retain the virus. If this area is damaged, it is easy for virus to enter.
Treatment of gastric cancer
The most direct and effective method is resection. If metastasis occurs and cannot be removed, radiotherapy is the next best option (indirectly resected – burned off, but easily metastasized). The most effective methods of chemotherapy are dulcolax and morphine.
The reason why cancer is not treated with drugs is that drugs that can kill viruses outside the body are strong oxidants that enter the body and kill not only cancer cells but also normal cells. It can inhibit the growth of tumor, and likewise inhibit the growth of normal cells. It can inhibit the inflammatory response of tumor, and also inhibit the normal immune response. Since all the normal tissues that are metabolically active are inhibited, patients will experience hair loss (hair is the most active growth area), nausea, and lack of appetite. This is the reason why chemotherapy patients suffer and are not cured. People are always dying, so it is better to end it earlier than to live and suffer. Dulcolax and morphine are the best choices. When I first became a doctor, I always followed my teacher’s advice to avoid patient addiction. If the teacher did not teach well, I was too stupid and did not know how to adapt. Even if an oncology patient becomes addicted, how many days can he or she live? Letting them go peacefully is better than living and suffering.
The mechanism of gastric vomiting
As mentioned before, the upper mouth (cardia) of the stomach is loose and the lower mouth (pylorus) is tight. The pylorus is most likely to release fluid, and it is difficult to pass lumpy substances. After eating stimulating food (e.g. alcohol), the pylorus becomes edematous and peristalsis decreases causing gastric peristalsis not to pass down normally but to return and upload. In an overfull state, the lower part of the stomach has weak peristalsis, and peristalsis cannot be transmitted downward, so it forms retroperistalsis toward the upper part. The gastric retroperistalsis squeezes the food into the esophagus, and the amount is small, which is reflux. A large amount is vomiting. In short, whenever the pyloric peristalsis decreases (food stimulation or neurological inhibition), the peristalsis of the stomach near the pylorus cannot pass down in sequence, and then it passes in the reverse direction, causing food to rush out of the cardia and vomiting occurs.
How to take care of the stomach?
Stomach care starts at a young age. The principle of stomach care is not to eat without hunger. Do not eat very warm food. Do not eat full meals. Eat food that can be easily digested (soaked) by the stomach.
1 Three meals a day is the habit of rural people, is formed by sunrise and sunset. Urban people work and rest irregularly, you can not have three meals a day, you can have more or less meals a day. Do not eat hungry, hungry must eat, food can not be full.
2 to avoid excessive stomach content (overeating). First, too much food can lead to gastric cavity expansion, thinning of the stomach wall, gastric wall blood vessels are stretched and squeezed damage, gastric wall ischemic necrosis. Second, excessive dilution of stomach acid does not ensure effective concentration of bacteria and viruses that enter the stomach.
3 Avoid starvation (no food in the stomach) No food in the stomach leads to a concentration of stomach acid higher than the tolerance level of the mucosa of the stomach wall, which can burn the mucosa of the stomach wall. It also informs the brain in reverse, reducing the secretion of gastric acid and leading to atrophy of the gastric glands.
4 Eat room temperature food, not hot and iced food. The Chinese at the dinner table like to say the phrase “eat while it’s hot”. I do not know that hot food is easy to damage the digestive tract. It is better to eat cold food. When the rice is ready, let it cool before eating it is good for your health. Animals do not cook, they eat cold food. We are animals evolved, will use fire to eat hot. But the body is still adapted to cold food. The body is adapted to the temperature at room temperature, too cold and too hot will damage the body. Hot food can burn tissue cells. The same is true in reverse. Frozen food can freeze the digestive tract and inhibit its peristalsis.
5 Chew and swallow slowly. This old adage is very true. Repeated chewing (destroy teeth, hard food crushed after the entrance is good), the food will be crushed, can reduce the burden on the stomach.
6 When eating, it is not appropriate to think and get angry. Thinking or angry are sympathetic excitement state, inhibit gastric peristalsis and gastric juice secretion, resulting in the stomach contents fall accumulation, feel discomfort. Over time, there will be fallen pressure parts of the erosion and ulcers. 7 Adequate sleep. During sleep, the brain rests, while inhibiting sympathetic nerves, sympathetic nerve interference is reduced, parasympathetic nerves are relatively excited, gastric peristaltic force is enhanced, the frequency increases, gastric gland secretion increases, gastric content and gastric wall contact time is short, gastric wall burden is reduced, even if there is erosion and ulcers, it is easy to heal. 8 Food that is difficult to digest is crushed first. It can reduce the burden on the mouth and stomach. This is one of the reasons why northerners grow stronger than southerners. Rice is the staple food in the south. After hulling, it is cooked and ready to eat. In the stomach, it is not easy to make rice grains into pulp. Northerners staple food noodles, is crushed products, in the stomach easily into a pulp, into the intestines easily absorbed. As for the Chinese often say food to eat five colors and five tastes does not make any sense. The stomach does not have eyes and taste buds, and the stomach’s perception of food is only divided into chunks or fluids.
How to eat drugs that are irritating to the stomach
There are many medicines that are irritating to the stomach. Doctors’ orders for taking such drugs are to take them after meals. Why is that? Because that is what their teachers taught them. Generations are misrepresented (no generation uses its brain).
For a drug that is irritating to the stomach to be less irritating to the stomach, it must be taken at the beginning of a meal on an empty stomach. This has two main points, one is an empty stomach and the other is the beginning of the meal. It means that the medicine is taken immediately after eating one or two bites of food in a hungry state. This will ensure that the drug will cause the least irritation to the stomach. The principle is the structure of the stomach and the way the stomach digests as mentioned earlier.
When the stomach is empty, gastric juices are stored in the pyloric opening of the greater curvature of the stomach, and the initial food slides down to the pyloric opening along the side of the greater curvature of the stomach through the cardia. If the drug is taken at this time, the drug dissolves at the pyloric opening and mixes with the initial food to form a paste-like fluid (chyme), and even if there is irritation, it is only in part of the pyloric opening. With subsequent food and gastric peristalsis, the drug can even be the first to pass through the pylorus into the duodenum without being completely melted. If the drug is taken after a meal, the melted drug is located in the uppermost part of the slurry stomach contents, and the stomach walls through which it passes are coated with a layer of irritant.
This is like filling a bucket of water and then pouring a small spoonful of oil on top of the water. If a hole is opened at the bottom of the bucket to release the water, after the water is released, the oil all hangs (stays) on the wall of the bucket.
For many elderly people, the stomach empties slowly, and when they want to take medicine, there is often still food in the stomach that has not been emptied, so they can take the medicine directly, and then eat full (mostly full).