Signalling from the gut lumen

The lining of the gastrointestinal tract needs to be easily accessible to nutrients and, at the same time, defend against pathogens and chemical challenges. This lining is the largest and most vulnerable surface that faces the outside world. To manage the dual problems of effective nutrient conversion and defence, the gut lining has a sophisticated system for detection of individual chemical entities, pathogenic organisms and their products, and physico-chemical properties of its contents. Detection is through specific receptors that signal to the gut endocrine system, the nervous system, the immune system and local tissue defence systems. These effectors, in turn, modify digestive functions and contribute to tissue defence. Receptors for nutrients include taste receptors for sweet, bitter and savoury, free fatty acid receptors, peptide and phytochemical receptors, that are primarily located on enteroendocrine cells. Hormones released by enteroendocrine cells act locally, through the circulation and via the nervous system, to optimise digestion and mucosal health. Pathogen detection is both through antigen presentation to T-cells and through pattern-recognition receptors (PRRs). Activation of PRRs triggers local tissue defence, for example, by causing release of antimicrobials from Paneth cells. Toxic chemicals, including plant toxins, are sensed and then avoided, expelled or metabolised. It continues to be a major challenge to develop a comprehensive understanding of the integrated responses of the gastrointestinal tract to its luminal contents.

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An overview of Natural Superdisintegrants

Research Journal of Topical and Cosmetic Sciences ◽

10.52711/2321-5844.2021.00016 ◽

2021 ◽

pp. 113-124

Author(s):

Shushank Sharma

Keyword(s):

Gastrointestinal Tract ◽

Aqueous Media ◽

Chemical Properties ◽

Cost Effective ◽

Oral Route ◽

Drug Formulation ◽

Release Time ◽

Disintegration Time ◽

Physico Chemical ◽

Set Up

The oral route is the most convenient route of administration for various drugs. It is viewed as the most convenient, most secure, and economical route for patients. Fast disintegrating tablets are popular these days as they disintegrate in the mouth within a few seconds without the use of water. The burdens of regularly used medications in pediatric and geriatric patients have been overwhelmed by quick-dissolving tablets. Natural superdisintegrants have been used for fast-dissolving tablets because they are biodegradable, chemically inert, non-harmful, more affordable, and generally accessible. Natural polymer improves the properties of the tablet as it is commonly used as diluents and binders. Natural super disintegrants decrease the release time and give healthful results to the patients. Most polymers are obtained from nature, they are cost-effective, non-toxic, and non-irritants. Disintegration is the most important step for releasing the drug from the tablet matrix to decrease the disintegration time. In this, drug and polymers come in contact with water, it swells, hydrate, and react chemically to release the drug in the mouth and gastrointestinal tract. Superdisintegrants are those substances that encourage the quick breaking down with a lesser amount contrasted with disintegrants. The quick disintegrants tablets are set up by utilizing suitable polymers which rely on the Physico-chemical properties of drugs and excipients, for example, drug and polymer compatibility, hardness and thickness of tablet, nature of drug and excipients, PH of drug and release parameters of drug formulation. Superdisintegrants are the vehicles added to tablet formulation to advance the breaking of tablets and capsules into small microparticles in aqueous media resulting in to increase in the surface area and promote quick drug release. The disintegrants have a significant capacity to oppose the efficacy of tablet binders and compression forces to form the tablet. Commonly there are three methods to incorporate disintegrants into the tablet: A. Inner addition, B. External expansion, C. Internal, and external addition. Most of the regularly based tablets are those expected to be swallow, disintegrate and release medicaments in the gastrointestinal tract but over a while tablets are manufactured to deliver medicaments in the mouth and gastrointestinal tract within few seconds of swallowing. It has been demonstrated that characteristic polymers are more effective than synthetic polymers. Some research is going to develop safe and effective medication with super disintegrating agents that can be dissolved rapidly to treat the disease.

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A review: An overview of Natural Superdisintegrants

Research Journal of Topical and Cosmetic Sciences ◽

10.52711/2321-5844.2021.00003 ◽

2021 ◽

pp. 13-24

Author(s):

Shushank Sharma ◽

Sikha Chauhan

Keyword(s):

Gastrointestinal Tract ◽

Aqueous Media ◽

Chemical Properties ◽

Cost Effective ◽

Oral Route ◽

Drug Formulation ◽

Release Time ◽

Disintegration Time ◽

Physico Chemical ◽

Set Up

The oral route is the most convenient route of administration for various drugs. It is viewed as the most convenient, most secure, and economical route for patients. Fast disintegrating tablets are popular these days as they disintegrate in the mouth within a few seconds without the use of water. The burdens of regularly used medications in pediatric and geriatric patients have been overwhelmed by quick-dissolving tablets. Natural superdisintegrants have been used for fast-dissolving tablets because they are biodegradable, chemically inert, non-harmful, more affordable, and generally accessible. Natural polymer improves the properties of the tablet as it is commonly used as diluents and binders. Natural super disintegrants decrease the release time and give healthful results to the patients. Most polymers are obtained from nature, they are cost-effective, non-toxic, and non-irritants. Disintegration is the most important step for releasing the drug from the tablet matrix to decrease the disintegration time. In this, drug and polymers come in contact with water, it swells, hydrate, and react chemically to release the drug in the mouth and gastrointestinal tract. Superdisintegrants are those substances that encourage the quick breaking down with a lesser amount contrasted with disintegrants. The quick disintegrants tablets are set up by utilizing suitable polymers which rely on the Physico-Chemical properties of drugs and excipients, for example, drug and polymer compatibility, hardness and thickness of tablet, nature of drug and excipients, PH of drug and release parameters of drug formulation. Superdisintegrants are the vehicles added to tablet formulation to advance the breaking of tablets and capsules into small microparticles in aqueous media resulting in to increase in the surface area and promote quick drug release. The disintegrants have a significant capacity to oppose the efficacy of tablet binders and compression forces to form the tablet. Commonly there are three methods to incorporate disintegrants into the tablet: A. Inner addition, B. External expansion, C. Internal, and external addition. Most of the regularly based tablets are those expected to be swallow, disintegrate and release medicaments in the gastrointestinal tract but over a while tablets are manufactured to deliver medicaments in the mouth and gastrointestinal tract within few seconds of swallowing. It has been demonstrated that characteristic polymers are more effective than synthetic polymers. Some research is going to develop safe and effective medication with super disintegrating agents that can be dissolved rapidly to treat the disease.

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Chronic kidney disease (CKD)

Oxford Desk Reference Nephrology ◽

10.1093/med/9780198777182.003.0013 ◽

2021 ◽

pp. 526-607

Keyword(s):

Chronic Kidney Disease ◽

Vitamin D ◽

Nervous System ◽

Gastrointestinal Tract ◽

Kidney Disease ◽

Endocrine System ◽

Waste Products ◽

Nitrogenous Waste ◽

Wide Range ◽

The World

Chronic kidney disease (CKD) results from a wide range of disease processes that vary in prevalence across the world. However, the manifestations and complications of CKD are broadly common to all causes of CKD and result from the accumulation of nitrogenous waste products, abnormal electrolyte, water, and acid-base regulation, and loss of regulated production of erythropoietin, renin, and vitamin D. This chapter provides an overview of the approach to the patient with CKD and then provides a structured description of the pathogenesis of the complications of CKD according to the organ or system affected, including the cardiovascular system, the liver and gastrointestinal tract, the endocrine system, the skin, the nervous system, and the blood.

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II. The intestine as a sensory organ: neural, endocrine, and immune responses

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1999.277.5.g922 ◽

1999 ◽

Vol 277 (5) ◽

pp. G922-G928 ◽

Cited By ~ 68

Author(s):

John B. Furness ◽

Wolfgang A. A. Kunze ◽

Nadine Clerc

Keyword(s):

Nervous System ◽

Gastrointestinal Tract ◽

Immune Cells ◽

Endocrine System ◽

The Body ◽

Sensory Organ ◽

Vascular Perfusion ◽

The Central Nervous System ◽

Irritable Bowel ◽

Integrated Response

The lining of the gastrointestinal tract is the largest vulnerable surface that faces the external environment. Just as the other large external surface, the skin, is regarded as a sensory organ, so should the intestinal mucosa. In fact, the mucosa has three types of detectors: neurons, endocrine cells, and immune cells. The mucosa is in immediate contact with the intestinal contents so that nutrients can be efficiently absorbed, and, at the same time, it protects against the intrusion of harmful entities, such as toxins and bacteria, that may enter the digestive system with food. Signals are sent locally to control motility, secretion, tissue defense, and vascular perfusion; to other digestive organs, for example, to the stomach, gallbladder, and pancreas; and to the central nervous system, for example to influence feeding behavior. The three detecting systems in the intestine are more extensive than those of any other organ: the enteric nervous system contains on the order of 108 neurons, the gastroenteropancreatic endocrine system uses more than 20 identified hormones, and the gut immune system has 70– 80% of the body's immune cells. The gastrointestinal tract has an integrated response to changes in its luminal contents. When this response is maladjusted or is overwhelmed, the consequences can be severe, as in cholera intoxication, or debilitating, as in irritable bowel syndrome. Thus it is essential to obtain a full understanding of the sensory functions of the intestine, of how the body reacts to the information, and of how neural, hormonal, and immune signals interact.

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Fiber in Broiler Feed: Its Effect on Performance, Gastro-intestinal Tract, and Microbial Profile

Indonesian Bulletin of Animal and Veterinary Sciences ◽

10.14334/wartazoa.v31i3.2754 ◽

2021 ◽

Vol 31 (3) ◽

pp. 119

Author(s):

Intan Nursiam ◽

Muhammad Ridla ◽

Nahrowi Nahrowi ◽

Widya Hermana

Keyword(s):

Gastrointestinal Tract ◽

Growth Performance ◽

Chemical Properties ◽

Oat Hulls ◽

Microbial Profile ◽

Fiber Analysis ◽

Physico Chemical ◽

Beet Pulp ◽

Gastro Intestinal Tract ◽

Broiler Feed

<p>In AGP ban era, addition of a fiber source in broiler feed improves the performance and development of the gastrointestinal tract. This paper aims to describe the differences in fiber analysis methods and the effect of fiber source addition on growth, development of the gastrointestinal tract, and microbiota profile in the digestive tract of broilers. Oat hulls, sugar beet pulp, rice hulls, pea hulls, sunflower hulls, wheat bran, and wood have been tested as fiber source in broiler feed. The effectiveness of fiber in increasing growth performance and stimulating the development of the gastrointestinal tract were influenced by the physico-chemical properties, level of addition, particle size, and fraction composition of the fiber source. Exploration of local fiber sources from Indonesia, which can have ability to increase growth performance and gastrointestinal tract development of broilers is needed to support food security in the future.</p>

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Decoration of specific sites on freeze-fractured membranes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081565 ◽

1978 ◽

Vol 36 (2) ◽

pp. 140-141

Author(s):

H. Gross ◽

H. Moor

Keyword(s):

Pure Water ◽

Freeze Fracture ◽

Chemical Properties ◽

Surface Forces ◽

Sulfate Pentahydrate ◽

Copper Sulfate Pentahydrate ◽

Physico Chemical ◽

Water Of Hydration ◽

Small Container ◽

Binding Forces

Fracturing under ultrahigh vacuum (UHV, p ≤ 10-9 Torr) produces membrane fracture faces devoid of contamination. Such clean surfaces are a prerequisite foe studies of interactions between condensing molecules is possible and surface forces are unequally distributed, the condensate will accumulate at places with high binding forces; crystallites will arise which may be useful a probes for surface sites with specific physico-chemical properties. Specific “decoration” with crystallites can be achieved nby exposing membrane fracture faces to water vopour. A device was developed which enables the production of pure water vapour and the controlled variation of its partial pressure in an UHV freeze-fracture apparatus (Fig.1a). Under vaccum (≤ 10-3 Torr), small container filled with copper-sulfate-pentahydrate is heated with a heating coil, with the temperature controlled by means of a thermocouple. The water of hydration thereby released enters a storage vessel.

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PHYSICO CHEMICAL PROPERTIES OF NICKEL OXIDE AT HIGH TEMPERATURE

Le Journal de Physique Colloques ◽

10.1051/jphyscol:1976798 ◽

1976 ◽

Vol 37 (C7) ◽

pp. C7-438-C7-442 ◽

Cited By ~ 2

Author(s):

R. FARHI ◽

G. PETOT-ERVAS

Keyword(s):

High Temperature ◽

Nickel Oxide ◽

Chemical Properties ◽

Physico Chemical

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Physico-Chemical Properties of Recombinant Desulphatohirudin

Thrombosis and Haemostasis ◽

10.1055/s-0038-1645073 ◽

1990 ◽

Vol 63 (03) ◽

pp. 499-504 ◽

Cited By ~ 4

Author(s):

A Electricwala ◽

L Irons ◽

R Wait ◽

R J G Carr ◽

R J Ling ◽

...

Keyword(s):

Molecular Weight ◽

Gel Filtration ◽

Chemical Properties ◽

Alpha Helix ◽

Apparent Molecular Weight ◽

Correlation Spectroscopy ◽

Nmr Studies ◽

Recombinant Hirudin ◽

Physico Chemical ◽

Recombinant Molecule

SummaryPhysico-chemical properties of recombinant desulphatohirudin expressed in yeast (CIBA GEIGY code No. CGP 39393) were reinvestigated. As previously reported for natural hirudin, the recombinant molecule exhibited abnormal behaviour by gel filtration with an apparent molecular weight greater than that based on the primary structure. However, molecular weight estimation by SDS gel electrophoresis, FAB-mass spectrometry and Photon Correlation Spectroscopy were in agreement with the theoretical molecular weight, with little suggestion of dimer or aggregate formation. Circular dichroism studies of the recombinant molecule show similar spectra at different pH values but are markedly different from that reported by Konno et al. (13) for a natural hirudin-variant. Our CD studies indicate the presence of about 60% beta sheet and the absence of alpha helix in the secondary structure of recombinant hirudin, in agreement with the conformation determined by NMR studies (17)

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