NUTRITIONAL ASPECTS OF ANASTOMOTIC OPERATIONS—With Special Reference to the Sprue Syndrome

Necessary but radical operation which results in short-circuits between various levels of the digestive tract, with or without resections of portions of the esophagus, stomach or intestine, frequently cures the condition for which the operation was done, but leaves the patient with difficult nutritional problems. These nutritional disturbances are usually associated with inability to maintain or gain weight as a result of badly regulated movement of food material through the altered digestive tract, and by the removal or diversion of important digestive secretions, such as those elaborated by the stomach, pancreas, duodenum and small bowel.Increased intestinal rate and diminished specific gastrointestinal secretions reduce the ability of the small bowel to properly absorb food, with resulting malnutrition, deficiency disease, and at times specific avitaminosis. Inability to absorb fat and fat-soluble substances is a constant feature of these conditions. Successful treatment of the nutritional problems involves constant, prolonged overfeeding of nonbulky foods, usually given in regular, frequently administered meals of small volume. Vitamin concentrates may occasionally be of some temporary assistance but are not needed if a balanced diet is given and may cause undesirable and sometimes dangerous symptoms. The use of supplemental substances, such as liver extract and a wetting agent, such as “Tween 80,” to improve fat absorption have been demonstrated to be of value.The postoperative conditions described are fairly similar to the condition known as sprue, and it is possible that the general principles underlying the treatment of this disease apply to the entire group of post-operative nutritional disturbances alluded to.     

Digestive tract motor correlates of vomiting and nausea

The digestive tract from the upper esophageal sphincter to the ileum participates in the vomiting process, but the role of the digestive tract in nausea is unclear. In preparation for vomiting, the proximal stomach relaxes and the small intestine is evacuated orad in a single mass movement by a retrograde giant contraction and caudad in a stripping fashion by a series of phasic contractions. Orad evacuation of the small intestine may not only remove offending substances but may also dilute. or buffer gastric contents with intestinal and pancreaticobiliary secretions. In association with retching and vomiting, the striated muscle of the esophagus contracts longitudinally, pulling the relaxed proximal stomach into the thoracic cavity forming a funnel from stomach to esophagus. However, gastric evacuation does not occur until the hiatal fibers of the diaphragm relax during vomitus expulsion. Nausea is a subjective feeling in humans that is difficult to identify in animals. Various changes in digestive tract activity have been associated with nausea, but no evidence suggests that these events cause nausea. The prodromal signs of vomiting (e.g., increased heart rate and respiration) that occur concomitantly with the gastrointestinal motor correlates of vomiting have been considered autonomic indices of nausea in animals, but this has not been proven. Regardless, the gastrointestinal motor correlates of vomiting do not cause the prodromata. The emetic central pattern generator may be organized in parallel with respect to its individual autonomic correlates, but as groups of responses, the autonomic and somatomotor correlates may be organized in series.     

PRELIMINARY STUDIES OF THE GASTROINTESTINAL TRACT WITH COLLOIDAL BARIUM

A stable colloidal suspension of barium sulfate has been developed and tested in roentgen examination of the gastrointestinal tract. The new material is rather distinctive in radiographic appearance and can usually be differentiated from simple barium-water mixtures by inspection of roentgenograms of the opacified stomach and small intestine. It usually affords a satisfactory demonstration of the mucosal folds of the stomach and duodenal bulb and is considerably more resistant to flocculation and precipitation by retained gastric secretions. In the small intestine, it has little tendency to undergo flocculation and fragmentation, and permits visualization of fine mucosal configurations with unusual clarity. Its motility is about the same as that of conventional suspensions. Air contrast colon examinations with the colloidal preparation exhibit a very uniform, opaque, and stable coating of the bowel wall and are more consistently satisfactory than when simple barium-water mixtures are used.     

禁食和重喂食对大绒鼠消化道长度与重量的影响

为探讨禁食和重喂食对栖息于横断山地区大绒鼠(Eothenomys miletus)消化道形态的影响,对禁食和重喂食条件下大绒鼠消化道各项指标进行了测定.实验分别测定了大绒鼠禁食12h、24 h、36 h和重喂食12 h、48 h、7d后的总消化道、胃、小肠、大肠、盲肠的长度及其含内容物重、去内容物重、干重.结果表明:禁食后,总消化道含内容物重、胃含内容物重和胃去内容物重增加,重喂食7d后均恢复到对照组水平.小肠含内容物重在禁食12h时最大,在重喂食12h时最小,重喂食48 h后恢复到对照组水平.禁食和重喂食条件下,大绒鼠的大肠和盲肠各指标均没有显著变化.以上结果表明,大绒鼠在食物受到限制、饥饿等胁迫因子作用下,可能通过调节消化道形态来满足部分能量需求,维持正常的生理机能.大绒鼠的消化道在禁食和重喂食中表现出的变化模式,可能与其食物资源时常波动的野外生存环境有关,从一方面反映了该物种在食物胁迫下的生存机制和适应对策.     

Anatomy and histology of the digestive system of the paddlefish (Polyodon spathula)

The paddlefish (Polyodon spathula) is one of the most primitive and unique freshwater fishes of North America. It is adapted as a plankton filter-feeder. The wide mouth and greatly expansible pharyngeal cavity allows it to process a large quantity of water. Numerous setiform gillrakers, which operate against the flattened surfaces of the gill arches and opercula, are capable of filtering out small food particles. The abundance of taste buds and mucus secreting cells in the buccal cavity and pharynx probably aids in selecting and entangling the food. The first segment of the stomach is provided with peculiar, large longitudinal rods of fat which may help in selecting food from water by causing occlusion of the small lumen when the striated fibers of the muscularis contract. Teeth, unnecessary for microphagous fishes, are absent in adults. The digestive tube is one of the most complex present in fishes. It has two distinct divisions of the stomach and four distinct divisions of the intestine besides possessing a large caecum. Ciliated epithelial cells occur in many parts of the gut and may be an aid in moving or processing the small items of food. Besides the presence of cilia, other primitive features of the digestive tract include the lack of distinction between the esophagus and stomach, the presence of a spiral valve, and the presence of some of the diffuse pancreatic tissue within the wall of the gut. The numerous Peyer's patches in the wall of much of the intestine may be an immunological response to the heavy parasitic infestation.     

Early development of the digestive tract of cod larvae, Gadus morhua L., during start-feeding and starvation

Cod larvae, Gadus morhua L., were reared in the laboratory and released to a large marine enclosure 4 to 5 days after hatching (6–8° C). The development of the digestive system was studied until day 24 after hatching. Morphological investigations of the jaw apparatus and the digestive tract showed that the larvae are able to absorb ingested food well before exhaustion of the yolk sac. The foregut, and especially the midgut, were particularly active in lipid absorption, and the hindgut was characterized by pinocytotic activity. Duhng the first days of feeding, no distinct prey organisms were observed in the gut, and signs of food absorption in the epithelial cells of the gut were sparse.A distinct red fluorescence, restricted to the hindgut, was observed from day 11 to day 19. On the basis of changes in absorptive pattern in the gut we suggest that changes in digestive and absorptive abilities, as well as in nutritional needs, take place around days 15–17 after hatching.
In starved larvae, signs of degeneration of the gut tissue were first visible in the foregut. By day 9 after hatching, microvilli was degenerated to such an extent that the ability to absorb food must have been severely restricted. If larvae are starved longer than this, they will probably not survive.     

The digestive systems of carnivorous plants

To survive in the nutrient-poor habitats, carnivorous plants capture small organisms comprising complex substances not suitable for immediate reuse. The traps of carnivorous plants, which are analogous to the digestive systems of animals, are equipped with mechanisms for the breakdown and absorption of nutrients. Such capabilities have been acquired convergently over the past tens of millions of years in multiple angiosperm lineages by modifying plant-specific organs including leaves. The epidermis of carnivorous trap leaves bears groups of specialized cells called glands, which acquire substances from their prey via digestion and absorption. The digestive glands of carnivorous plants secrete mucilage, pitcher fluids, acids, and proteins, including digestive enzymes. The same (or morphologically distinct) glands then absorb the released compounds via various membrane transport proteins or endocytosis. Thus, these glands function in a manner similar to animal cells that are physiologically important in the digestive system, such as the parietal cells of the stomach and intestinal epithelial cells. Yet, carnivorous plants are equipped with strategies that deal with or incorporate plant-specific features, such as cell walls, epidermal cuticles, and phytohormones. In this review, we provide a systematic perspective on the digestive and absorptive capacity of convergently evolved carnivorous plants, with an emphasis on the forms and functions of glands.

A comparison of the forms and functions of digestive and absorptive glands in carnivorous plants sheds light on their convergent evolution.     

新疆干旱环境中褐家鼠消化道长度和重量的季节变化及其适应意义

动物消化道的形态与食性、食物质量以及动物对能量的需求密切关系。本文对新疆干旱环境中生存的褐家鼠在自然环境中消化道长度及重量进行了测定,结果表明,家栖的褐家鼠只有总消化道、小肠和大肠的长度有季节差异,冬、春季高于夏、秋季。同时发现捕自阿拉山口的褐家鼠胃长度和干重有季节差异。     

Ultrastructure and histochemistry,of the stomach of Asplanchna sieboldi

Stomach cells of female Asplanchna sieboldi are specialized for absorption and intracellular digestion of nutrients. Evidence is presented to show that electron-opaque colloidal substances, present in the medium and within digestive vacuoles of the prey (Paramecium), are taken up by the stomach cells at the apical cell membrane and sequestered within food vacuoles which contain hydrolases working in both the acid and alkaline pH range. The stomach cells are also implicated in the absorption of molecules below the resolving power of the electron microscope. In rotifers possessing a complete digestive tract, this task is presumed to be handled by the intestine.     

Relating Food Emulsion Structure and Composition to the Way It Is Processed in the Gastrointestinal Tract and Physiological Responses: What Are the Opportunities?

The gastrointestinal tract is a complex and intricate machinery to process and absorb nutrients from food in a highly controlled and efficient way. One of the main purposes is to provide essential nutrients (proteins, fats, and carbohydrates) to the blood in a soluble form that can be further processed by the body. For this reason, the food is digested by various enzymes and brought into a state in which it can be absorbed by the small intestines. The proliferation of obesity in the Western world has motivated several research groups to study the digestion process, ultimately to control food intake by food design. This paper reviews the literature related to the digestion of food emulsions, describing in detail the organization and function of the various organs of the gastrointestinal tract, the way these organs cooperate and how this cooperation is regulated by physiological signals. The insight may help to cross the bridge toward designed food structuring from a food-engineering and physical–chemical perspective. Based on the physiological understanding of fat digestion, opportunities to affect the digestion of triglycerides by food structure and composition, stability under stomach conditions, and delayed digestion and absorption in the small intestine are identified.     

Coupling of growth to nutritional status: The role of novel periphery-to-brain signaling by the CCHa2 peptide in Drosophila melanogaster

ABSTRACT

The coupling of growth to nutritional status is an important adaptive response of living organisms to their environment. For this ability, animals have evolved various strategies, including endocrine systems that respond to changing nutritional conditions. In animals, nutritional information is mostly perceived by peripheral organs, such as the digestive tract and adipose tissues, and is subsequently transmitted to other peripheral organs or the brain, which integrates the incoming signals and orchestrates physiological and behavioral responses. In Drosophila melanogaster, adipose tissue, known as the fat body, functions as an endocrine organ that communicates with the brain. This fat body-brain axis coordinates growth with nutritional status by regulating the secretion of Drosophila insulin-like peptides (Dilps) from the brain. However, the molecular nature of the fat body-brain axis remains to be elucidated. We recently demonstrated that a small peptide, CCHamide-2 (CCHa2), expressed in the fat body and gut, directly stimulates its receptor (CCHa2-R) in the brain, leading to Dilp production. Notably, the expression of CCHa2 is sensitive to the presence of nutrients, particularly sugars. Our results, together with the results of previous studies, show that signaling between peripheral organs and the brain is a conserved strategy that couples nutritional availability to organismal physiology.     

大绒鼠消化道形态的季节变化

为探讨栖息于横断山地区大绒鼠(Eothenomys miletus)的消化道特征与环境之间的适应关系,对自然环境中大绒鼠消化道各项指标进行了测定.实验分别测定了不同季节大绒鼠胃、小肠、大肠、盲肠的长度,及其含内容物重、去内容物重、干组织重.结果表明,大绒鼠消化道特征存在季节性变化,随着温度降低、食物质量下降,大绒鼠的小肠、盲肠长度增加;各器官重量均在6月份最大;大绒鼠在低温、食物质量下降、繁殖等胁迫因子作用下,通过增加食物摄入、调节消化道形态来满足能量需求的增加,维持正常的生理机能.大绒鼠的消化道在不同季节中表现出的变化模式,与其低纬度高海拔、年平均温度较低的生存环境有关,从一方面反映了该物种在温度胁迫下的生存机制和适应对策.     

Distribution of endocrine cells in the digestive tract of Alligator sinensis during the active and hibernating period

The digestive tract is the largest endocrine organ in the body; the distribution pattern of endocrine cells varies with different pathological and physiological states. The aim of the present study was to investigate the distributed density of 5-hydroxytryptamine (5-HT), gastrin (GAS), somatostatin (SS) and vasoactive intestinal peptide (VIP) immunoreactive (IR) cells in the digestive tract of Alligator sinensis during the active and hibernating period by immunohistochemical (IHC) method. The results indicated that 5-HT-IR cells were distributed throughout the entire digestive tract, which were most predominant in duodenum and jejunum. The density increased significantly in stomach and duodenum during hibernation. GAS-IR cells were limited in small stomach and small intestine. The density decreased significantly in small stomach during hibernation, while increased in duodenum. What's more, most of the endocrine cells in duodenum were generally spindle shaped with long cytoplasmic processes ending in the lumen during hibernation. SS-IR cells were limited in stomach and small stomach. The density increased in stomach while decreased in small stomach during hibernation, meanwhile, fewer IR cells occurred in small intestine. VIP-IR cells occurred in stomach and small stomach. The density decreased in small stomach, while increased in stomach during hibernation. These results indicated that the endocrine cells in different parts of digestive tract varied differently during hibernation, their changes were adaptive response to the hibernation.     

神农架地区4种啮齿类食性及脏器形态差异比较

生活在同一地域的物种,会因强烈的资源竞争而产生生态位重叠与分离,从而实现相互共存。以神农架地区啮齿动物为研究对象,比较分析不同啮齿类食性、脏器重量及消化道形态差异,探索其共存机制及其生理生态学上的适应策略。食性上,安氏白腹鼠(Niviventer andersoni)、社鼠(N.confucianus)、高山姬鼠(Apodemus chevrieri)、中华姬鼠(A.draco)均为杂食者,但各自喜食偏好不同,安氏白腹鼠的食物组成以植物枝叶和种子为主,社鼠、高山姬鼠和中华姬鼠的食物组成均以种子和动物性食物为主。与各自生态习性及其食性相适应,不同啮齿动物的脏器重量及消化道形态发生相应的变化。脏器重量上,不同啮齿动物心鲜重、肺鲜重、脾鲜重和干重无显著差异,其它指标差异显著。安氏白腹鼠的心干重、肺干重、肝鲜重和干重、肾鲜重和干重显著大于社鼠、高山姬鼠和中华姬鼠。消化道形态上,不同啮齿动物盲肠长、净鲜重和干重无显著差异,其它指标差异显著。其中,胃含内容物鲜重、净鲜重和干重,盲肠含内容物鲜重,大肠长、含内容物鲜重、净鲜重和干重均以安氏白腹鼠具较大值,但各自变化趋势不同;小肠长、含内容物鲜重、净鲜重和干重则以社鼠具较大值。且同属姬鼠属的高山姬鼠和中华姬鼠脏器重量及消化道形态各指标间均无显著差异。由于小泡巨鼠和猪尾鼠数量较少,未进行统计分析。以上结果显示:食物资源利用上的分化有利于安氏白腹鼠与其近缘物种社鼠及其他鼠类的同域共存,且为适应不同的食物资源利用模式,其脏器及消化道形态也发生了适应性的变化;同域分布的近缘物种高山姬鼠、中华姬鼠则有可能采取其它策略而非食物资源分化模式实现共存。     

Development of gastrointestinal and pancreatic functions in mammalians (mainly bovine and porcine species): influence of age and ingested food

This review summarizes recent advances in knowledge on the development of digestive tissues and their productions as well as mechanisms of regulation in response to age and ingested food in mammalian species (mainly bovine and porcine species). In the first two sections, changes are reported for stomach, pancreas and small intestine, and examined in relation to different situations (colostral, milk feeding and weaned periods). The implication of some regulatory substances (growth factors, gut regulatory peptides and neurohormonal substances) in regulation mechanisms is discussed over these periods. For example, the plasma pattern of several gut regulatory peptides and the expression of their specific receptors could explain certain phenomena of digestive development. Recent cellular and molecular aspects of regulation of the digestive enzyme production are also reported. Finally, an approach to interactions existing between age and ingested food is given in the last section. In conclusion, although some phenomena are well established, it is often difficult to distinguish what the age- and food-dependent events are in the development of the digestive function.     

黑斑侧褶蛙消化道重量及长度的性别和季节差异

消化道是联系脊椎动物能量摄入和能量支出之间关系的纽带,其重量和长度对外界环境具有高度的敏感性和弹性(flexibility)。以黑斑侧褶蛙(Pelophylax nigromaculata)为研究对象,测定了山东聊城地区2012年夏季(16只,8♀/8♂)、秋季(19只,9♀/10♂)及翌年春季(17只,8♀/9♂)其体重、体长、胴体湿重和干重系数、总消化道及各段(食道、胃、小肠和大肠)的湿重、干重和长度系数的性别和季节差异(双因素方差分析),对有性别差异的指标,用单因素方差分析分别比较了雌、雄蛙的季节差异。结果显示,1)雌蛙的体重、体长均高于雄蛙,都在秋季最高,春季或夏季最低;雄蛙的胴体湿重系数高于雌蛙,夏季高于秋季;胴体干重系数既无性别差异,也无季节差异。2)除食道湿重系数无性别差异外,雌蛙总消化道及各段的湿重系数均高于雄蛙;除胃湿重系数无季节差异外,春季或秋季的总消化道及各段的湿重系数都高于夏季;雌蛙的总消化道干重和胃干重系数高于雄蛙,食道、小肠和大肠的干重系数无性别差异,所有的干重系数均无季节性差异。3)除雌蛙的大肠长系数高于雄蛙外,总消化道及各段的长度系数均无性别差异,春季和秋季的总消化道长、食道长及胃长系数均高于夏季,小肠长和大肠长系数均无季节性差异。结果表明,随着季节更替,黑斑侧褶蛙消化道各段的重量和长度表现出一定的弹性特征,这与各器官的功能及其生活环境的多样性是相适应的。     

ON THE PERMEABILITY OF THE STOMACH MUCOSA FOR ACIDS AND SOME OTHER SUBSTANCES

1. Solutions approximately isotonic with blood of strong and weak acids, several salts, glucose, and glycine were introduced in the resting stomachs of cats. The concentration and volume changes were recorded. 2. It was found that the stomach mucosa was permeable to the majority of the ions tested. There was also a permeability in the opposite direction from the blood (mucosa) to the stomach content, particularly of alkali chlorides. Poorly permeable substances were glucose, glycine, and sodium iodate. Pure weak acids such as acetic acid penetrated very rapidly. 3. The electrolyte concentration changes in the stomach content (or gastric juice) are pictured as an exchange diffusion; for instance, the hydrogen ions of an acid are exchanged against alkali ions of the mucosa or blood. 4. It is pointed out that the concept of the mucosa as an ion permeable membrane could be used as the foundation of a "diffusion theory," which can explain the acidity and chloride variations of the gastric juice without postulating neutralizing or diluting secretions.     

Structure of the digestive tract of the pluteus larva of Dendraster excentricus (Echinodermata: Echinoida)

Summary Histological and ultrastructural observations of the digestive tract of eight-armed plutei of Dendraster excentricus are reported. The esophagus is divided into two regions. The uppermost is a narrow tube comprised of ciliated cells that assist in transporting food to the more bulbous lower esophagus where food particles are formed into a bolus prior to entering the stomach. The esophagus is surrounded by a network of smooth muscle fibers that are predominantly oriented circumferentially in the upper esophagus, and longitudinally in the lower esophagus. The musculature of the upper esophagus produces peristaltic contractions, whereas contractions of the muscle of the lower esophagus open the cardiac sphincter and force food from the lower esophagus into the stomach. Axons are associated with the ciliated cells and the muscles of the upper esophagus. The cardiac sphincter consists of a ring of myoepithelium, with cross-striated myofibrils oriented around the bases of the cells. The gastric epithelium is comprised of two cell types. Type I cells, which predominate, absorb and store nutrients, and may be the source of secreted digestive enzymes. Type II cells apparently phagocytize and intracellularly digest whole algal cells. The intestine is comprised of relatively unspecialized cells and probably functions primarily as a conductive tube for the elimination of undigested materials.     

洞庭湖区社鼠消化道长度和质量的季节变化

对洞庭湖区社鼠（Niviventer confucianus）自然种群四季的消化道各器官的长度和质量进行了测定。结果表明。消化道指标季节变化明显。总体消化道含内容鲜质量、净鲜质量与干质量均具有显著的季节变化。以冬、春季较高。夏、秋季较低。消化道各器官的变化与总消化道不尽相同。其中,以胃的变化相对比较稳定。仅长度的变化达显著水平,以冬季最短,夏、秋季较长。这是动物为适应繁殖季节能量需求而增加摄食量的反应,也与夏秋季食物丰富度有关。小肠、盲肠、大肠的长度和质量指标（内容鲜质量、净鲜质量和干质量）以冬、春季较高。夏、秋季较低。这是该鼠对冬、春季低温和食物匮乏的适应性反应。总体来说。洞庭湖区社鼠为适应夏、秋季繁殖盛期能量需求增加的主要对策是增加摄食量;而为适应冬、春季低温环境和食物数量和质量减少的主要对策是增大消化道。提高消化效率。