OBJECTIVETo study the mechanism of lactose intolerance (LI) by cloning the mouse lactase cDNA and recombining a vector. METHODS Total murine RNA was isolated from the small intestine of a 4-week-old BALB/c mouse (d). Gene-specific primers were designed and synthesized according to the cDNA sequences of lactase-phlorizin hydrolase (LPH) in human, rat, and rabbit. A coding sequence (CDS) fragment was obtained using RT-PCR, and inserted into a clone vector pNEB-193, then the cDNA was sequenced and analyzed using bioinformatics.

RESULTSThe cDNA from the BALB/c mouse with 912 bp encoding 303 amino acid residues. Analysis of the deduced amino acid sequence using bioinformatics revealed that this cDNA shared extensive sequence homology with human LPH containing a conserved glycosyl hydrolase family 1 motif important for regulating lactase intolerance.

CONCLUSIONBALB/c mouse LPH cDNA (GenBank accession No: AY751548) provides a necessary foundation for study of the biological function and regulatory mechanism of the lactose intolerance in mice.

Animals ; Cloning, Molecular ; DNA, Complementary ; Humans ; Lactase-Phlorizin Hydrolase ; genetics ; Mice ; Mice, Inbred BALB C

OBJECTIVE: The specific activity of lactase-phlorizin hydrolase (LPH) is very high at birth and sharply declines after weaning, producing lactose intolerance. The prevalence of lactose intolerance is up to 85% in Korean adults. Molecular basis of the regulatory mechanisms responsible for the decline of LPH specific activity is still unknown. In order to elucidate the molecular mechanisms regulating the LPH expression during development, LPH specific activity and mI4NA level of Korean fetal and adult intestines were compared. METHODS: 20 fetal small intestines (16-27 weeks) were obtained during therapeutic abortion and were divided into 3 equal length. 20 adult jejunal tissues were obtained from patients without small intestinal disease during laparotomy. Mucosal homogenates were prepared for dissacharidases specific activities measurement and total RNA was extracted for northern and slot hvbridization. LPH mRNA level was measured by laser densitometer. RESULTS: LPH specific activities of proximal, middle and distal portion of fetal intestines (n=20) were 36.2 +/- 22.5, 38.6 +/- 23.2 and 23.2 +/- 19.9 mu/mg protein, respectively. LPH specific activity of adult jejunum (n=8) was 5.9 +/- 1.8 mu/mg protein and significantly (p<0.05) lower than those of fetal intestines. However, there was no significant difference in sucrase and trehalase specific activities between fetal intestines and adult jejunum. Although LPH specific activity of adult jejunum was lower than those of fetal intestines, LPH mBNA level of adult jejunum was as high as those of fetal intestines. CONCLUSION: These results show that LPH specific activity and mRNA level do not parallel, indicating the posttranscriptional control of fetal development of LPH expression.
Abortion, Therapeutic ; Adult* ; Female ; Fetal Development ; Fetus* ; Humans ; Intestinal Diseases ; Intestine, Small* ; Intestines ; Jejunum ; Lactase* ; Lactase-Phlorizin Hydrolase ; Lactose Intolerance ; Laparotomy ; Parturition ; Pregnancy ; Prevalence ; RNA ; RNA, Messenger* ; Sucrase ; Trehalase ; Weaning

Chronic diarrhea in children has a long differential diagnosis, but the clinician can usually distinguish disease from functional diarrhea. A careful history will provide information on medical and dietary problem, growth disturbance, associated symptoms and signs. The extent of laboratory evaluation should be guided by common sense. In the absence of the worrisome historical items noted, or abnormal findings on examination or growth history, reassurance may be all that is required. This article reviewed the diagnostic approach and differential diagnosis of chronic diarrhea, and summarized common non pathologic conditions of chronic diarrhea such as chronic nonspecific diarrhea (toddler's diarrhea) and secondary lactase deficiency.
Child ; Diagnosis, Differential ; Diarrhea ; Humans ; Infant ; Lactase ; Lactose Intolerance

In 1962, Durand suggested the term primary lactose intolerance for the disorder withch resulted from a defect of the lactase activity in the intestinal mucosa. However primary lactose intolerance is rare and it is not commonly encountered in routine pediatric practice. Apart from such a primary lactose intolerance, diarrhea, meteorism, and abdominal discomfort after taking lacose containing food are more frequently encoumtered in case of gastroenteritis in which damage of the intestinal mucosa and coating of the mucosa by inflammatory secretions lead to decreased lactase it form the primary lactose intolerance. It is now considered that secondary lactose intolerance may play an important role in case of infantile diarrhea commonly encoutered in pediatric practice. The auther tried the lactase preparation Galantase?to evaluated it's clinical effect on infantile diarrhea of various kind (50 cases). Evaluation of the effect of Galantase was made on the bases of the following criteria. l Marked effective ; nature of stools and number per day returned to normal within 3 days after Galantase administration. l Effective ; nature of stools and number per day decreased within 3 days after Galantase administration. l Ineffective ; all stools remained unchainged and diarrheic. The results obtsined by this study are as followes l Marked effective ; 78 % l Effective ; 12 % l Slight effective ; 4% l Ineffective ; 6% There was no undesirable side effect observed in all 50 cases. Based upon the above effective rate, we concluded that the Galantase is a quite effective medicament for infantile diarrhea, especially for primary and secondary lactose intolerance.
Diarrhea ; Diarrhea, Infantile* ; Gastroenteritis ; Infant ; Intestinal Mucosa ; Lactase ; Lactose Intolerance ; Meteoroids ; Mucous Membrane

OBJECTIVETo investigate the development of lactose intolerance in neonates with non-infectious diarrhea and its association with diarrhea, and to evaluate the diagnostic values of fecal pH value and urine galactose determination for neonatal lactase deficiency.

METHODSSeventy hospitalized neonates who developed non-infectious diarrhea between October 2012 and June 2015 were enrolled as the diarrhea group, and 162 hospitalized neonates without non-infectious diarrhea were enrolled as the non-diarrhea group. Test paper was used to determine fecal pH value. The galactose oxidase method was used to detect urine galactose. The neonates with positive galactose oxidase were diagnosed with lactase deficiency, and those with lactase deficiency and diarrhea were diagnosed with lactose intolerance. According to the results of urine galactose detection, 69 neonates in the diarrhea group who underwent urine galactose detection were classified into lactose intolerance group (45 neonates) and lactose tolerance group (24 neonates), and their conditions after treatment were compared between the two groups. The follow-up visits were performed for neonates with diarrhea at 3 months after discharge.

RESULTSFecal pH value and positive rate of urine galactose (65% vs 54%) showed no significant differences between the diarrhea and non-diarrhea groups (P>0.05). Fecal pH value showed no significant difference between the lactose intolerance and lactose tolerance groups (P>0.05), while the neonates in the lactose intolerance group had a significantly longer time to recovery of defecation than those in the lactose tolerance group (P<0.05).

CONCLUSIONSThe incidence of lactase deficiency is high in neonates, and diarrhea due to lactose intolerance tends to occur. Determination of fecal pH value has no significance in the diagnosis of lactose intolerance in neonates with diarrhea.

Diarrhea, Infantile ; etiology ; Galactose ; urine ; Humans ; Hydrogen-Ion Concentration ; Infant, Newborn ; Lactase ; deficiency ; Lactose Intolerance ; complications

OBJECTIVE: To study the efficacy and safety of lactase additive in improving lactose intolerance in preterm infants. METHODS: A total of 60 preterm infants with lactose intolerance who were admitted to the Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from January 2018 to December 2019 were randomly divided into a lactase treatment group and a control group, with 30 infants in each group. The infants in the lactase treatment group were given 4 drops of lactase additive (180 mg) added into preterm formula or breast milk, and those in the control group were given placebo, oral administration of probiotics (live combined RESULTS: Finally 29 infants in the lactase treatment group and 26 infants in the control group completed the trial. At the end of the first week after intervention, compared with the control group, the lactase treatment group had significantly lower frequency of daily milk vomiting and gastric retention amount ( CONCLUSIONS Lactase additive can safely and effectively improve the clinical symptoms caused by lactose intolerance in preterm infants.
China ; Female ; Humans ; Infant ; Infant, Newborn ; Infant, Premature ; Lactase ; Lactose ; Lactose Intolerance/drug therapy* ; Prospective Studies

Cow milk allergy can be defined as an adverse immunologic reactions to cow milk protein. The term is often mistakenly applied to other causes of milk intolerence, such as lactase deficiency and galactosemia, which must be differenciated and excluded. We have experienced 10 children of cow milk allergy at neonatal onset who had suffered from G-I symtoms, such as diarrhea, irritability, weight loss, vomiting and abdominal distension. One half of this patients had family history of allergic diseas. All patients have positive specific IgE RAST to cow's milk protein, milk elimination test and milk challenge test. Brest milk feeding and soy bean formula feeding and soy bean formula feeding have started after diagnosis and then gastrointestinal symtoms and signs of all patients are improved but other allergic diseases are combined in 5 children.
Child ; Diagnosis ; Diarrhea ; Galactosemias ; Humans ; Hypersensitivity* ; Immunoglobulin E ; Infant* ; Lactase ; Milk ; Milk Hypersensitivity ; Milk Proteins ; Soybeans ; Vomiting ; Weight Loss

PURPOSE: The activity of epithelial lactase (LCT) is associated with a polymorphism 13910 bp upstream in the lactase encoding gene. Because the association between the LCT-13910 polymorphism and the risk for colorectal cancer is not clear, we investigated the role of the LCT-13910 polymorphism as a potential risk factor for colorectal cancer and colorectal polyps in the Turkish population. METHODS: One hundred sixty-six subjects (74 with polyps, 44 with colorectal cancer, 48 controls), who had undergone a total colonoscopy between January 2012 and November 2012 in our endoscopy unit were genotyped for the LCT-13910 polymorphism by using the polymerase chain reaction and minisequencing. RESULTS: The CC genotype in the lactose gene 13910 locus, which is accepted as the genetic indicator of lactase deficiency, was determined as 83.7%. The CC genotype rate was determined as 89.1% in patients who had a history of lactose intolerance and 81.5% in those without a history of lactose intolerance (P = 0.236). No difference was detected between the patients who had colorectal polyp(s) and/or cancer and the controls with regard to the LCT-13910 polymorphism. No differences were determined between groups when they were compared with regard to the C or the T allele. CONCLUSION: No differences were detected between the patients who had colorectal polyp(s) and/or cancer and those with normal colonoscopy findings with regard to lactase gene polymorphisms. No differences were determined between the groups when they were compared with regard to the C or the T allele.
Adenocarcinoma ; Alleles ; Colonoscopy ; Colorectal Neoplasms* ; Endoscopy ; Genotype ; Humans ; Lactase ; Lactose ; Lactose Intolerance ; Polymerase Chain Reaction ; Polyps ; Risk Factors

Calcium is an essential nutrient that is necessary for many functions in human health. Calcium is the most abundant mineral in the body with 99% found in teeth and bone. Only 1% is found in serum. The serum calcium level is tightly monitored to remain within normal range by a complex metabolic process. Calcium metabolism involves other nutrients including protein, vitamin D, and phosphorus. Bone formation and maintenance is a lifelong process. Early attention to strong bones in childhood and adulthood will provide more stable bone mass during the aging years. Research has shown that adequate calcium intake can reduce the risk of fractures, osteoporosis, and diabetes in some populations. The dietary requirements of calcium and other collaborative nutrients vary slightly around the world. Lactose intolerance due to lactase deficiency is a common cause of low calcium intake. Strategies will be discussed for addressing this potential barrier to adequate intake. The purpose of this narrative review is a) to examine the role of calcium in human health, b) to compare nutrient requirements for calcium across lifecycle groups and global populations, c) to review relationships between calcium intake, chronic disease risk, and fractures, and d) to discuss strategies to address diet deficiencies and lactose intolerance.
Aging* ; Calcium* ; Chronic Disease ; Diet ; Humans ; Lactase ; Lactose Intolerance ; Metabolism ; Nutritional Requirements ; Osteogenesis ; Osteoporosis ; Phosphorus ; Reference Values ; Tooth ; Vitamin D

OBJECTIVETo Prepare surface functional magnetic microspheres for the separation of vascular endothelial growth factor (VEGF) nucleic acid and lactase enzyme immobilization.

METHODSUsing suspension polymerization methods to copolymerize MA-styrene containing magnetite nanoparticles and GMA-styrene also containing magnetite nanoparticles, respectively. Both the carboxyl-modified magnetic microspheres and epoxy-modified magnetic microspheres were obtained. In addition, the chloromethyl-modified magnetic microspheres were prepared by seedy microemulsion. The magnetic microspheres bound with b-gamma IgG were determined by radioimmunoassay (RIA), and the separation of VEGF nucleic acid and lactase enzyme immobilization were performed by carboxyl-modified magnetic microspheres.

RESULTSTransmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS) and infrared (IR) spectra showed that the products of polymer magnetic microspheres were monodispersed and that the magnetic particles were uniformly distributed in the microsphere with special functional group on the surface of the microsphere. RIA showed that three kinds of magnetic microspheres could be bound with b-gamma IgG and the absorption of b-gamma IgG reached 75 micrograms/mg, especially for the carboxyl-modified magnetic microspheres. The carboxyl-modified magnetic microspheres can be used for the separation of VEGF nucleic acid by coupling with corresponding primer. Moreover, the immobilized enzyme was proportional to the amount of the carboxyl-modified magnetic microspheres.

CONCLUSIONSThe surface functional magnetic polymer microspheres can be bound with active bio-substance, and have a wide application prospect in the fields of biology and medicine.

Adsorption ; Endothelial Growth Factors ; chemistry ; Enzymes, Immobilized ; Immunoglobulin G ; Lactase ; metabolism ; Magnetics ; Microspheres ; Nanotechnology ; Nucleic Acids ; isolation & purification ; Particle Size