In 1935, Grant (1) successfully demonstrated the in vitro biosynthesis of lactose from glucose in slices of guinea pig mammary gland. Lactose was determined by a differential fermentation method. Under the conditions employed, sugar phosphates were not converted to lactose either in slices or minces of lactating gland. Recently this work was confirmed and extended by Malpress and Morrison (a), ...

BACKGROUND Lactose, as the primary osmotic component in milk, is the major determinant of milk volume. Glucose is the primary precursor of lactose. However, the effect of glucose on lactose synthesis in dairy cow mammary glands and the mechanism governing this process are poorly understood. RESULTS Here we showed that glucose has the ability to induce lactose synthesis in dairy cow mammary ep...

Escherichia coli lactose permease (LacY) transports sugar across the inner membrane of the bacterium using the proton motive force to accumulate sugar in the cytosol. We have probed lactose conduction across LacY using steered molecular dynamics, permitting us to follow molecular and energetic details of lactose interaction with the lumen of LacY during its permeation. Lactose induces a widenin...

The effect of milled and micronized lactose fines on the fluidization and in vitro aerosolization properties of dry powder inhaler (DPI) formulations was investigated, and the suitability of static and dynamic methods for characterising general powder flow properties of these blends was assessed. Lactose carrier pre-blends were prepared by adding different lactose fines (Lactohale 300, 230 and ...

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...

OBJECTIVES to study the prevalence of lactose malabsorption with increasing age and to determine whether lactose malabsorbers consume less dietary calcium, have lower bone mineral density or display faster bone loss than lactose absorbers. DESIGN 80 healthy Caucasian women aged 40-79 years (20 per decade) were studied for 1 year. METHODS breath hydrogen exhalation was measured for 3 after a...

Introduction Lactose malabsorption arises from lactase deficiency and may lead to lactose intolerance - gastrointestinal symptoms after lactose ingestion. Occurrence and severity of the symptoms are influenced by many factors, including the dose of lactose and the intensity of its colonic fermentation to short chain fatty acids and gases. Material and methods The hydrogen breath test (HBT) af...

OBJECTIVE This work aimed to evaluate and correlate symptoms, biochemical blood test results and single nucleotide polymorphisms for lactose intolerance diagnosis. METHOD A cross-sectional study was conducted in Fortaleza, Ceará, Brazil, with a total of 119 patients, 54 of whom were lactose intolerant. Clinical evaluation and biochemical blood tests were conducted after lactose ingestion and ...

The capacity of intestinal lactase (EC 3.2.1.23) of piglets to hydrolyse lactose in vivo was investigated by measuring the response of blood galactose to doses of lactose, galactose plus glucose and both whole and skimmed milk. Following the administration of oral doses of lactose dissolved in water to piglets from 2 to 18 d of age the adjusted galactose area under the curve (AUC) was between 1...

OBJECTIVE This paper reports on the status of lactose digestion during early and late pregnancy and at 8 weeks postpartum in an African-American population. The hypothesis is that lactose digestion and milk tolerance do not change throughout pregnancy and do not differ from those of non-pregnant African-American women. DESIGN AND SUBJECTS This longitudinal study determined lactose digestion a...