Using an electrical technique for measuring transjejunal potential differences (PDs) in conscious man, we have estimated the electrogenic absorption of the hexoses liberated by hydrolysis of lactose which was infused into the jejunum of one normal control and 21 patients with diarrhoea. The results were compared with jejunal lactase levels determined from biopsy specimens taken from the recordi...

BACKGROUND Anaphylactic reactions involving IgE mediated hypersensitivity have been frequently reported for a number of uncommon foods. However, cases of anaphylaxis to over the counter vitamins and oral supplements have been rarely published. Lactose intolerance affects approximately 20% of Canadians and roughly 70% of the world's population of any age. Lactose intolerance develops primarily d...

Because human fetuses of 26-30 weeks gestation are known to have low levels of intestinal mucosal lactase activity, it has been assumed that live born preterm neonates of comparable gestational age are also lactase deficient. We have previously shown that disaccharidase activities in jejunal fluid in infants are highly significantly correlated with enzyme activities in the adjacent mucosa. We h...

The jejunal disaccharidases, sucrase, maltase and lactase, were determined in jejunal biopsies obtained from 43 malnourished children and 10 controls. In the study group, 63% were girls and 93% had severe malnutrition. Lactase activity was significantly reduced in third and fourth degree malnutrition (p < 0.05 and p < 0.005, respectively), but maltase activity was significantly reduced only in ...

BACKGROUND Milk is an important source of nutrients. The consumption of milk, however, may cause abdominal complaints in lactose intolerant individuals. The frequency of -13910C/C genotype is known to be high among Northern Russians, exceeding the prevalence in northern Europe. In our study we tested two hypotheses: 1) subjects with lactase non-persistent genotype (-13910C/C) have more gastroin...

Lactase activity declines during postnatal development in rats, but little is known about the underlying molecular mechanism of this phenomenon. We attempted to clarify whether the regulation was at the transcriptional or post-transcriptional level and to examine the effects of dietary factors on that regulation. Newborn rats were divided into two groups, prolonged nursing and weaning, at d 21....

Lactase activity declines during postnatal development in rats, but little is known about the underlying molecular mechanism of this phenomenon. We attempted to clarify whether the regulation was at the transcriptional or post-transcriptional level and to examine the effects of dietary factors on that regulation. Newborn rats were divided into two groups, prolonged nursing and weaning, at d 21....

This thesis is based on the following original articles, which are referred to in the text by their Roman numerals. In addition, some unpublished data are presented Assignment of the locus for congenital lactase deficiency to 2q21, in the vicinity of but separate from the lactase-phlorizin hydrolase gene. Identification of a variant associated with adult-type hypolactasia. Transcriptional regul...

Background Lactose intolerance is the insufficient ability to digest lactose, a sugar commonly found in dairy products. It is caused by a deficiency of the enzyme lactase, which is resident in the small intestine. Lactase breaks down lactose into glucose and galactose, which are readily absorbed into the bloodstream. Lactase deficiency develops slowly over time, most persons concerned do not ex...

The Metabolic Syndrome (MetS) is defined as a pattern of metabolic disturbances, which include central obesity, insulin resistance and hyperglycemia, dyslipidemia, and hypertension. Milk has been promoted as a healthy beverage that can improve the management of MetS. Most human adults, however, down-regulate the production of intestinal lactase after weaning. Lactase encoded by the LCT gene is ...