Galactose intolerance

The extent to which the level of galactose-l-phosphate uridyl transferase activity in erythrocytes reflects the level in the liver is unknown except for a bandful of cases. This problem is worth further investigation with particular reference to these 2 groups of heterozygotes, those showing unusual galactose intolerance and those with very low enzymatic activity. 

Galactose intolerance Voriconazole tablets contain lactose and should not be given to patients with rare hereditary problems of galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption. 

Caution in proarrhythmic conditions, electrolyte abnormalities, galactose intolerance, lactase deficiency, hematologic malignancy... 

Hereditary fructose intolerance is caused by an autosomal recessive hereditary defect of the enzyme fructose-l-phosphate aldolase. Whenever fructose is supplied, severe hypoglycaemia and functional disorders occur in the liver, kidneys and CNS. The prevalence is estimated at 1 20,000 births. As with galactose intolerance, the gene which codes aldolase B is also localized on chromosome 9. This enzyme defect causes fructose-l-phosphate to accumulate in the liver and tissue. The cleavage of fructose-1,6-biphosphate is only slightly compromised since the enzymes aldolase A and C are available for this process. The consumption of phosphate and ATP in the tissue results in various functional disorders (i.) inhibition of gluconeogenesis in the liver and kidneys, (2.) increase in lactate in the serum with metabolic acidosis, (3.) decrease in protein synthesis in the liver, and (4.) functional disorders of the proximal tubular cells with development of Fanconi s syndrome, (s. pp 593, 594) (193, 194, 196, 198)... 

To test for galactose intolerance (decreased hepatic uptake) in Fanconi-Bickel syndrome. 

The liver s role is to maintain chemical homeostasis and it can, in certain circumstances, be stressed by means of a metabolic load. One example has been to administer an oral fructose load which causes minimal spectral changes in normal subjects but, at very low dosage, results in an increase in the fructose-1-phosphate peak in patients with fructose intolerance. Other metabolic stresses have been administered to investigate galactose intolerance, glycogen storage diseases and cirrhosis. The rat liver (in situ or perfused) has been studied to elucidate details of carbohydrate and fatty acid metabolism, sometimes by a combination of and P NMR. The control of pH in the liver has also been studied. 

Lactose, the milk sugar, is a reducing disaccharide consisting of glucose and galactose moieties. The estimated annual worldwide availability of lactose as a byproduct from cheese manufacture is several million tons [1,2], but only about 400 000 t/a lactose is processed further from cheese whey [3], Non-processed whey is an environmental problem due to its high biochemical and chemical oxygen demand [2], The use of lactose as such is limited by two main factors relatively low solubility of lactose in most solvents and lactose intolerance in human body [1]. 

Small-intestine lactase (GH 1), the absence of which is associated with lactose intolerance in a large proportion of the adult population, was probed with monodeoxy as well as selected mono-O-methyl derivatives in the galactose moiety of methyl lactosides.112 This enzyme required hydroxyl groups at C-2 and also C-3, while neither the presence of a 4-OH group nor a specific configuration at C-4 was prerequisites for successful hydrolysis. A 6 -deoxy lactoside was readily hydrolyzed, but the absence of 6-OH in the gluco moiety caused it to be a poor substrate. 

The nutritional and physiological effects of lactose in the diet have become of major interest to health professionals and the public with the finding that about 70% of the world population has low levels of lactase activity in the intestine and, in many cases, an intolerance to lactose. A voluminous literature has developed (Delmont 1983 Renner 1983 Paige and Bayless 1981). Most problems with lactose digestion are attributable to the lactose molecule, but others may arise from the galactose moiety liberated on hydrolysis. 

There are several forms of intolerance to lactose and galactose. Primary adult lactase deficiency is a normal age-related decrease in lactase activity seen in the majority of adults. Secondary lactase deficiency is a transient state of low enzyme activity following injury to the intestinal mucosa as a result of diseases such as celiac sprue, infectious gastroenteritis, and protein-calorie malnutrition. The last two states are common conditions (Dahlqvist 1983). 

One of the largest-scale processes with enzymes is the hydrolysis of lactose to glucose and galactose (250 000 tpy) (Liese, 1999). As a significant fraction of consumers, especially in Asia, are lactose-intolerant, a condition which gives rise to rashes and stomach ailments, hydrolysis of lactose has considerable utility for the manufacture of lactose-free milk (Silk ). 

Lactose is hydrolyzed to glucose and galactose in the intestine by the enzyme lactase. People who are lactose-intolerant lack this enzyme. In these people, lactose advances in the digestive tract to the large intestine, where it is fermented by intestinal bacteria to produce large amounts of carbon dioxide and organic acids. Today, people with lactose intolerance can purchase milk in which the lactose has already been hydrolyzed, or can buy lactase supplements. 

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