Introduction
Paul Ong, Rachel Skittrall in Gastrointestinal Nursing, 2017
The digestive system is divided into two parts: the gastrointestinal tract and the accessory organs. The gastrointestinal (GI) tract is made up of a number of organs that are directly involved in the process of digestion: mouth, pharynx, oesophagus, stomach, small intestine, large intestine and rectum (Figure 1.1). The accessory organs are a group of organs that assist in the process of digestion, and they include the teeth, tongue and gallbladder, which facilitate digestion. There are also a number of digestive glands such as the salivary glands, liver and pancreas that produce secretions that assist in the process of digestion but are not considered part of the gastrointestinal tract. This is why they are termed accessory organs (Figure 1.2). These organs are constructed of specialised cells that perform different complex functions. How the cells are specialised is dependent upon the function they perform.
Obesity and Type 2 Diabetes Mellitus
John J.B. Anderson, Marilyn C. Sparling in The Mediterranean Way of Eating, 2014
Diabetes mellitus, or just diabetes, is a group of diseases characterized by high blood sugar (glucose) levels and other adverse changes, including those affecting arterial wall functions. In diabetes, dietary macronutrients (i.e., carbohydrates, fats, and proteins) are not metabolized in the normal way. Typically, all consumed foods are digested within the gastrointestinal tract to their basic component molecules. The simple sugar, glucose, results from the breakdown of starches and disaccharide sugars. In the small intestine, glucose is absorbed into the bloodstream to be used by the body’s cells for energy or, to a lesser extent, to be stored as glycogen for later use. For glucose to enter the body’s cells, the pancreatic hormone insulin must be secreted in sufficient amounts to lower the blood glucose concentration to its usual fasting or baseline level.
The Digestive (Gastrointestinal) System and Its Disorders
Walter F. Stanaszek, Mary J. Stanaszek, Robert J. Holt, Steven Strauss in Understanding Medical Terms, 2020
Nausea and vomiting generally occur together and can reflect the presence of acute abdominal emergencies, chronic indigestion, and acute systemic infections, as well as many diseases involving other body systems. They are often associated with abdominal pain. The medical term for vomiting is emesis.Colic can refer to spasmodic pains in the abdomen, to the paroxysms of pain seen in young infants, or to a variety of pain or cramping episodes due to a number of causes. Anorexia (loss of desire to eat) is a primary symptom in a number of disorders of the gastrointestinal tract and liver. Diverticula or pouches can occur along the intestinal wall. Meckel's diverticulum refers to such an area on the ileum that can produce ulceration and bleeding. Dlverticislosls denotes the presence of multiple sites; diverticulitis specifically describes inflammation.
The mesentery: an ADME perspective on a ‘new’ organ
Published in Drug Metabolism Reviews, 2018
Aneesh A. Argikar, Upendra A. Argikar
The development of mesentery during and after the embryonic stage has been covered in great detail elsewhere (Martini and Tallitsch 2014). To summarize the embryonic development, the endoderm forms the hindgut and the foregut. During the initial months of the embryo, the gut is just a simple tube. This simple digestive tube is suspended by the mesentery. After gradually disappearing, the ventral mesentery remains in two places, on the ventral surface of the stomach known as lesser omentum and between the liver and anterior abdominal wall known as falciform ligament. The lesser omentum provides stability to the stomach and also provides a way for the blood vessels and other structures to enter and leave the liver. As the embryo grows, the dorsal mesentery enlarges and forms a pouch called the greater omentum. The literature on the expression of enzymes and transporters in the embryonic and fetal mesentery was not available.
The Effects of Perioperative Probiotics on Postoperative Gastrointestinal Function in Patients with Brain Tumors: A Randomized, Placebo-Controlled Study
Published in Nutrition and Cancer, 2023
Mengyang Jiang, Xiaoyu Zhang, Yiqiang Zhang, Yang Liu, Ran Geng, Haixia Liu, Yongxing Sun, Baoguo Wang
The primary functions of the gastrointestinal tract are motility, secretion, absorption, and serving as a barrier. Nervous system disorders affecting gastrointestinal function are characterized primarily by abnormalities in motility rather than secretion (6). Gastrointestinal motility is regulated at multiple levels, including the central and enteric nervous systems as well as the microbiome (26,27). Surgery-induced stress and inflammatory responses activate the sympathetic and enteric nervous systems, leading to gastrointestinal dysfunction and thus disturbing motility and transit (28). This process involves the immune system, inflammatory cells, reactive enteric glia, neurons, smooth muscle cells, epithelial cells, and the microbiome in the intestinal lumen (8). Postoperative gastrointestinal dysfunction can not only cause short-term complications, but may also lead to long-term complications after inflammation subsides (29). The incidence of postoperative gastrointestinal dysfunction in adults with neurological diseases is more than twice that for individuals with non-neurological diseases (2).
Development and optimization of osmotically controlled drug delivery system for poorly aqueous soluble diacerein to improve its bioavailability
Published in Drug Development and Industrial Pharmacy, 2020
Magdy I. Mohamed, Abdulaziz M. Al-Mahallawi, Sami M. Awadalla
Osmotic pump Controlled Release Preparation is a novel drug delivery system. It gains a vital interest in oral solid dosage form development chiefly because of their ability to deliver drugs at constant rates (zero-order release) independent of media pH and hydrodynamics of the surrounding media [14,15]. Osmosis can be defined as the spontaneous movement of a solvent from a lower solute solution to a solution of higher solute concentration through an ideal semi-permeable membrane, which is permeable only to the solvent but impermeable to the solute [16,17]. The preparation consists of the core that contained the active material, a semi-permeable membrane that coated the core and an orifice, produced by a micro drill or mechanically to release the active material. When the system is in the gastrointestinal tract, fluid enters into the preparation and dissolves the active material within the core [14,17]. Thus the pressure formed in the preparation induces a release of the solution at a slow but continuous rate [18,19]. Therefore, solubility is considered one of the most vital factors affecting the drug release kinetics from the osmotic pump. As well as Osmotic pressure is another vital factor that imbibes water inside the osmotic pump, and it is proportional to the concentration of the osmotic agent [14].