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Biomedical subjects

J Schrezenmeir

Publications and source records attributed to J Schrezenmeir.

At least 19 recordsLinked to original sources

Ibandronate treatment reverses glucocorticoid-induced loss of bone mineral density and strength in minipigs.

The Göttingen minipig is one of the few large animal models that show glucocorticoid (GC)-induced bone loss. We investigated whether GC-induced loss of bone mineral density (BMD) and bone strength in minipigs can be recovered by treatment with the bisphosphonate ibandronate (IBN). 40 primiparous sows were allocated to 4 groups when they were 30 months old: GC treatment for 8 months (GC8), for 15 months (GC15), GC treatment for 15 months plus IBN treatment for months 8-15 (GC&IBN), and a control group without GC treatment. Prednisolone was given at a daily oral dose of 1 mg/kg body weight for 8 weeks and thereafter 0.5 mg/kg body weight. IBN was administered intramuscularly and intermittently with an integral dose of 2.0 mg/kg body weight. BMD of the lumbar spine (L1-3) was assessed in vivo by Quantitative Computed Tomography (QCT) at months 0, 8, and 15. Blood and urine samples were obtained every 2-3 months. After sacrificing the animals lumbar vertebrae L4 were tested mechanically (Young's modulus and ultimate stress). Histomorphometry was performed on L2 and mineral content determined in ashed specimens of T12 and L4. In the GC&IBN group, the GC associated losses in BMD of -10.5%+/-1.9% (mean+/-standard error of the mean, p<0.001) during the first 8 months were more than recovered during the following 7 months of IBN treatment (+14.8%+/-1.2%, p<0.0001). This increase was significantly larger (p<0.0001) than the insignificant +2.1%+/-1.2% change in group GC15. At month 15, the difference between groups GC&IBN and GC15 was 22% (p<0.01) for BMD, 48% (p<0.05) for Young's modulus, and 31% (p<0.14) for ultimate stress; bone-specific alkaline phosphatase showed trends to lower values (p<0.2) while deoxypyridinoline was comparable. This minipig study demonstrates that GC-induced impairment of bone strength can be effectively and consistently treated by IBN. GC&IBN associated alterations in BMD and bone turnover markers can be monitored in vivo using QCT of the spine and by biochemical analyses, reflecting the changes in bone strength.

Absorptiometry, Photon↗

Common familial influences on clustering of metabolic syndrome traits with central obesity and insulin resistance: the Kiel obesity prevention study.

OBJECTIVE: The phenotypic heterogeneity of metabolic syndrome (MSX) suggests heterogeneity of the underlying genotype. The aim of the present study was to examine the common genetic background that contributes to the clustering between the two main features (insulin resistance, central obesity) and different MSX component traits. METHODS: In all, 492 individuals from 90 families were investigated in a three-generation family path study as part of the Kiel Obesity Prevention Study (KOPS, 162 grandparents, 66.1+/-6.7 years, 173 parents, 41.3+/-5.4 years and 157 children, 10.8+/-3.4 years). Overall heritability was estimated and common familial (genetic and environmental) influences on insulin resistance (HOMA-IR) or central obesity (elevated waist circumference, WC), respectively, and different MSX traits were compared in a bivariate cross-trait correlation model. RESULTS: Prevalence of MSX (according to NCEP criteria) was 27.2% (f) and 27.8% (m) in adults and 3.5% (f) and 8.5% (m) in children and adolescents, respectively. MSX phenotype was found to be highly variable, comprising 16 subtypes of component trait combinations. Within-trait heritability was 38.5% for HOMA-IR and 53.5% for WC, cross-trait heritability was 53.4%. As much as 6-18% and 3-10% of the shared variance between different MSX component traits (lipid profile, blood pressure) and WC or HOMA-IR, respectively, may be genetic. With the exception of HDL-C, the shared genetic variance between MSX component traits and WC was higher than the genetic variance shared with HOMA-IR. CONCLUSION: A common genetic background contributes to the clustering of different MSX component traits and central obesity or insulin resistance. Common genetic influences favour central obesity as a major characteristic linking these traits.

Adult↗

Value of body fat mass vs anthropometric obesity indices in the assessment of metabolic risk factors.

OBJECTIVE: To compare the value of body fat mass (%FM) to indirect measures of general (body mass index (BMI)) and central adiposity (waist circumference (WC); waist-to-height ratio (WC/ht)) for the prediction of overweight- and obesity-related metabolic risk in a study population with a high prevalence of metabolic syndrome (MSX). METHODS: BMI, WC, WC/ht, body composition (by air-displacement plethysmography) and metabolic risk factors: triglycerides, cholesterol, HDL-cholesterol (HDL-C), uric acid, systolic blood pressure (BPsys), insulin resistance by homeostasis model assessment (HOMA-IR) and C-reactive protein (CRP) were measured in 335 adults (191 women, 144 men; mean age 53 +/-13.9 years, prevalence of MSX 30%). RESULTS: When compared with BMI and WC, %FM showed weaker associations with metabolic risk factors, except for CRP and BPsys in men. In women, HDL-C and HOMA-IR showed the closest correlations with BMI. For all other risk factors, WC or WC/ht were the best predictors in both sexes. Differences in the strength of correlations between an obesity index and different risk factors exceeded the differences observed between all obesity indices within one risk factor. In stepwise multiple regression analyses, WC/ht was the main predictor of metabolic risk in both sexes combined. However, analysis of the area under receiver operating characteristic curves for prediction of the prevalence of >or=2 component traits of the MSX revealed a similar accuracy of all obesity indices. CONCLUSIONS: At the population level, measurement of body FM has no advantage over BMI and WC in the prediction of obesity-related metabolic risk. Although measures of central adiposity (WC, WC/ht) tended to show closer associations with risk factors than measures of general adiposity, the differences were small and depended on the type of risk factor and sex, suggesting an equivalent value of methods.

Abdominal Fat↗

Preliminary evidence of FABP2 A54T polymorphism associated with reduced risk of type 2 diabetes and obesity in women from a German cohort.

The T54 variant of the FABP2 gene has shown an association with the insulin resistance syndrome in some, but not all, studies. Here, we tested the hypothesis that the association between FABP2 A54T genotype and type 2 diabetes (T2DM) is confounded by body mass index (BMI) and is different between the two genders. 192 incident cases of T2DM and 384 sex- and age-matched controls were taken from the EPIC-Potsdam study cohort. Logistic regression analyses revealed that BMI was a strong confounder for diabetes risk association among women. When adjusted for BMI, the homozygous T54 variant was significantly associated with reduced risk of T2DM in women (OR = 0.24, 95 %CI: 0.07 - 0.82), but not in men in the co-dominant inheritance model. Accordingly, HbA (1c) values were significantly lower in women carrying two T54 alleles with BMI regarded as covariate. While accounting for potentially confounding effects, linear trends of increased BMI and leptin values were observed in women according to the presence of T54 alleles. The interaction term (p = 0.04) of continuous BMI and T54-coding genotypes suggested that the T54 variant is an effect-modifier for BMI in females. We conclude that the T54 allele of FABP2 A54T is associated both with higher BMI and reduced risk of T2DM in women from the German EPIC-Potsdam study.

Adult↗

Association between functional FABP2 promoter haplotype and type 2 diabetes.

Fatty acid-binding protein 2 (FABP2) is a cytosolic protein expressed exclusively in epithelial cells of the small intestine. Some, albeit not conclusive, evidence indicates that the Thr-allele of FABP2 Ala54Thr polymorphism is associated with type 2 diabetes. More recently, common FABP2 promoter polymorphisms have shown association with postprandial increase of triglycerides, body composition and plasma lipid levels. Therefore, we reasoned that variants in the FABP2 promoter may also predispose to type 2 diabetes mellitus. In our Caucasian study population, we found three SNPs and three insertion-deletion polymorphisms that are in complete linkage disequilibrium defining promoter haplotype A and B within 1kb 5' of the FABP2 initiation codon. Haplotype calculations indicated that the FABP2 promoter and Ala54Thr variants were strongly linked. Functional analysis of promoter fragments demonstrated that haplotype difference is caused by polymorphisms within 260 bp downstream of the FABP2 initiation codon. Using a prospective case-control study nested within the EPIC-Potsdam cohort of 192 incident type 2 diabetes cases and 384 sex-/age-matched controls, male subjects carrying the FABP2 haplotype B allele showed significantly decreased risk of type 2 diabetes when adjusted for BMI (OR = 0.50, 95 % CI = 0.28 - 0.87, p < 0.05) and additional covariates (OR = 0.42, 95 % CI 0.22 - 0.81, p < 0.01). Further adjustment for the Ala54Thr polymorphism revealed an OR of 0.18 (95 % CI 0.06 - 0.49, p < 0.001). Similarly, Ala/Ala homozygote males carrying the promoter haplotype B had decreased risk (0.33, 0.11 - 0.94, p < 0.05) of type 2 diabetes after stratification for the Ala54Thr polymorphism. FABP2 promoter haplotypes or genotype combinations defined by the promoter and Ala54Thr polymorphism were not associated with BMI, body fat, leptin, HbA (1c), total cholesterol or HDL. In conclusion, our findings suggest that the functional FABP2 promoter haplotype may contribute to type 2 diabetes in a sex-specific manner.

Adult↗

Prospective, randomized controlled trial on Lactobacillus rhamnosus in infants with moderate to severe atopic dermatitis.

BACKGROUND: A reduction of symptoms of atopic dermatitis (AD) in small infants by the administration of Lactobacillus rhamnosus has been reported in a few studies. One study with older children and adolescents failed to show any effect. OBJECTIVES: We conducted a prospective study to reassess the efficacy of orally administered L. rhamnosus strain GG (LGG) in infants with AD. METHODS: In a randomized, double-blind, placebo-controlled study, 54 infants aged 1-55 months with moderate to severe AD were randomized to daily 10 x 10(9) colony-forming units of LGG or to placebo during an 8-week intervention phase. Emollients, class I-II topical corticosteroids and antihistamines were permitted. RESULTS: The treatment with LGG was well tolerated. At the end of treatment there were no significant differences between the groups with respect to clinical symptoms (SCORAD, pruritus, sleep loss), the use of topical corticosteroids and antihistamines, immunological parameters, or health-related quality of life of the parents. CONCLUSIONS: Our results could not confirm LGG as an effective treatment of AD in infancy.

Child, Preschool↗

Effect of a dietary supplement containing probiotic bacteria plus vitamins and minerals on common cold infections and cellular immune parameters.

OBJECTIVE: A randomized, double-blind, placebo-controlled intervention study was carried out in order to investigate whether consumption of a dietary supplement containing probiotic bacteria plus vitamins and minerals over a period of at least three months in winter/spring affects the duration, frequency, and severity of symptoms of naturally acquired common cold infections as well as cellular immune parameters. METHODS: 477 healthy men and women (aged 36 +/- 13, mean +/- SD) who had not been vaccinated against influenza were randomly assigned to a group who received daily the probiotic multivitamin and mineral supplement (verum) or a placebo, for three (n = 239) or for 5.5 months (n = 238). Cellular immune response was determined in 60 participants per study group by flow cytometry before and after 14 days of supplementation. RESULTS: The incidence of respiratory tract infections regarded as being virally induced was 13.6% lower in the verum group compared to the placebo group (p = 0.07). During respiratory tract infection episodes, the subjects recorded common cold and influenza-like symptoms daily. All symptoms were reduced in the verum group. We found a relative reduction of 19% in the total symptom score (p = 0.12), 25% in influenza symptoms (p = 0.09), and 54% in the number of days with fever (p = 0.03). The duration of these infections was not affected. Leukocytes, lymphocytes, in particular T-lymphocytes including CD4+ and CD8+ cells, as well as monocytes were significantly higher increased in the verum group, during the first 14 days of supplementation compared to placebo. CONCLUSION: These data indicate that the intake of a dietary supplement containing probiotic bacteria plus vitamins and minerals during a period of at least three months in winter/spring may reduce the incidence and the severity of symptoms in common cold infections in otherwise healthy adults. This may be due to stimulated cellular immunity.

Adult↗

Benefits of oral supplementation with and without synbiotics in young children with acute bacterial infections.

Acutely ill children (n = 129) aged 1-6 years receiving antibiotic therapy were randomized to receive a nutritional supplement with (PS) or without (P) synbiotics or a fruit-flavored drink (D) with their medications. Group PS had significantly greater weight gains (versus D) following antibiotic therapy. The percentages of subjects without bacterial illnesses 14 days following antibiotic therapy were as follows: 94.3% (PS), 87.8% (D), and 80.6% (P). PS (vs D) significantly increased fecal Lactobacillus in a subset of subjects. Oral supplements increase energy intake and promote weight gain in acutely ill children receiving antibiotics; synbiotics may confer additional benefits by increasing bifidobacteria levels.

Acute Disease↗

Safety of probiotics that contain lactobacilli or bifidobacteria.

Lactobacilli and bifidobacteria are extremely rare causes of infection in humans, as are probiotics based on these organisms. This lack of pathogenicity extends across all age groups and to immunocompromised individuals. Strains used for new probiotics should be chosen from the commensal flora of humans and should not carry intrinsic resistance to antibiotics that would prevent treatment of a rare probiotic infection. Vigilance regarding the detection of possible rare cases of infection due to probiotics should be maintained, and isolates should be sent to reference centers for molecular characterization and confirmation.

Bifidobacteriales Infections↗

Probiotics and non-intestinal infectious conditions.

Orally ingested probiotic micro-organisms do not exert health effects exclusively in the intestine. Some strains can alleviate or prevent bacterial, fungal or viral infections in other organs by stimulation of the immune system. By preservation or improvement of the barrier function of the intestinal mucosa, they may inhibit translocation of potential pathogens and thus prevent infections of the blood stream and other tissues and organs. Modulation of the intestinal microflora can affect the local microflora of the urogenital tract and possibly of the oral cavity. Finally, some strains of orally ingested bacteria reach target organs like the urogenital tract in a viable state; alternatively they can be applied locally. Despite the infection-preventing properties of probiotic bacteria, lactic acid bacteria have rarely been identified in infections of the blood stream, heart valves and other organs, usually only in patients with severe disease. It is the general opinion that in most cases the source of infection was the commensal microflora of the intestine or the oral cavity. Until now only one case of infection associated with administration of a probiotic strain has been published. The most promising health-promoting effects have been seen in vaginosis, urinary tract infections, Helicobacter pylori gastritis and infections of the respiratory tract in children. More controlled clinical trials with sufficient numbers of participants are needed to determine the scientific basis for the use of probiotic bacteria in infections in locations of the body other than the intestine.

Bacterial Infections↗

Inulin, oligofructose and mineral metabolism - experimental data and mechanism.

Numerous investigations performed in animal models in the past 10 years have shown repeatedly that non-digestible oligosaccharides (NDO), such as inulin, oligofructose or transgalacto-oligosaccharides (TOS), stimulate mineral absorption, mainly calcium and magnesium. Long-term beneficial effects on bone health have been indicated by accumulation of bone mineral content in growing rats or prevention of bone loss in ovariectomized rats. However, bone mineral content or density are not necessarily associated with bone quality. In recent studies both oligofructose and calcium prevented loss of trabecular bone area induced by oestrogen deficiency, this, however, occurred at different trabecular shapes. The effects of NDO on mineral metabolism may be based on the enhancement of passive and active mineral transport across the intestinal epithelium, mediated by an increase in certain metabolites of the intestinal flora and a reduction of pH. The possible impact of short-chain fatty acids, butyrate in particular, and of polyamines on the stimulation of mineral absorption capacity, and the interaction of oligofructose and antibiotics is discussed.

Animals↗

Detection of a promoter polymorphism in the gene of intestinal fatty acid binding protein (I-FABP).

Postprandial fat absorption is supposed to be a major factor in the development of the metabolic syndrome. In recent years, the assimilation of plasma triglycerides has been the focus of several groups, revealing a number of specific fat or fatty acid transporters. The intestinal fatty acid binding protein, I-FABP-2, participates in the absorption of nutritional fats. The influence of a coding polymorphism has been investigated intensively. However, it remains still unclear whether this polymorphism has a major impact on postprandial TG levels in humans. We found a polymorphism in the promoter of FABP-2, which might involve the retinoid receptor in the transcriptional activity. In functional analysis, we have been able to demonstrate that the various promoter alleles develop different activities in the human intestinal epithelial cells and that the postprandial appearance of plasma TGs in healthy subjects also depends on their genotype. Since the distribution of the identified promoter polymorphism does not differ in subjects suffering from type 2 diabetes, the overall influence on the development of the metabolic syndrome seems to be minor.

Adult↗

Improved yield and functionality of parathyroid cells separated by using collagenase-digestion with cold pre-incubation.

Preparation of cells from solid organs often induces a functional impairment due to the proteolytic cell damage by the applied digestive enzyme like collagenase, trypsin or dispase. To preserve the tissue and to enhance the yield of cells, Laue et al. reported an islet cell isolation with pre-incubation at 4 C permitting the enzyme to diffuse into the tissue and explicite activity equally throughout the whole particle. The aim of this study was to investigate whether this procedure can be applied to parathyroid glands. Therefore porcine parathyroid glands were dissected into 1 mm3 pieces. Subsequently one group of these pieces was incubated 22 h at 4 C in 2 mg/ml collagenase before activating the enzyme by elevating the temperature to 37 C for 30 min. The other group was incubated directly at 37 C for 30 min. The yield of cells and their viability was assessed by light-microscopy and staining with trypan-blue. After the cells were immobilized in barium-alginate and cultivated for 7 days, the function was tested by incubation in different calcium concentrations and PTH-measurement. Finally, the viability was assessed by histology. Using a cold pre-incubation with collagenase, a significantly higher number of isolated cells was retrieved compared with collagenase-digestion without pre-incubation. The viability was about 100% and did not differ between both groups. After immobilization and cultivation the viability decreased to less than 30%, with and without pre-incubation. In contrast to viability the PTH-secretion of the cells differed significantly between both procedures. By pre-incubation with collagenase at 4 C a gentle method is presented resulting in an enhancement of yield and function of single cells of parathyroid glands.

Animals↗

Effect of extracellular pH on insulin secretion and glucose metabolism in neonatal and adult rat pancreatic islets.

Changes in extracellular pH are known to affect glucose-stimulated insulin secretion. In the present study, glucose metabolism in pancreatic islets cultured at different pHs was investigated. Also, for islet transplantation purposes, insulin secretion and glucose metabolism were compared in neonatal and adult islets at different pHs to determine which islet preparation is more tolerant to acidity and alkalinity. The results revealed a dependency of insulin secretion on the external pH in both neonatal and adult islets. Reduction of insulin secretion was observed at both the acidic and alkaline sides of pH 7.3. Glucose stimulated increases of insulin secretion in all cases. Similar results were obtained for ATP and pyruvate contents. Intracellular insulin increased with the increase of pH value. In contrast, calcium content decreased with the increase of pH. The results demonstrate that neonatal islets are more acid tolerant than adult islets. Both basal and glucose-stimulated insulin secretions, as well as other parameters of neonatal islets were significantly higher than those of adult islets in response to low pH. The differences under alkaline conditions were not significant but give an indication that neonatal islets are more tolerant to alkalinity than are adult islets.

Adenosine Triphosphate↗

Postprandial triglycerides and endothelial function.

Several studies support the association between postprandially elevated triglyceride levels and atherosclerosis. Histological and cell culture investigations revealed, that triglyceride rich postprandial lipoproteins are taken up by macrophages and smooth muscle cells and are detectable as part of foam cells in vascular lesions. Remnant particles, generated by lipolysis of postprandial lipoproteins in vitro and fatty acids increase the permeability of the endothelium and are cytotoxic for endothelial cells. Besides these morphological changes of cells, lipoproteins have been shown to exert effects on cellular functions like the expression of membrane proteins and the production or release of several bioactive substances regulating communication with blood cells and other cell systems of the vascular wall, blood pressure and hemostasis. This review concentrates on the influence of postprandial lipoproteins on factors involved in the interaction of endothelial cells with blood leukocytes and factors mediating blood pressure regulation. Increased expression of adhesion molecules has been detected immunehistochemically in atherosclerotic plaques in animals and humans. It was demonstrated that patients with elevated triglyceride levels have increased levels of soluble adhesion molecules. Furthermore, postprandial lipoproteins were shown to induce membrane expression of adhesion molecules. This effect seems to be at least in part mediated by the oxidative modification of the particles. Accordingly chylomicrons separated after ingestion of safflower oil, rich in polyunsaturated linoleic acid, induced higher adhesion molecule expression at higher oxidant concentration compared with chylomicrons separated after ingestion of olive oil, rich in monounsaturated oleic acid. Several authors described effects of fatty acids on the expression of adhesion molecules. On the one hand, they may exert stimulatory effects as such, on the other hand cytokine induced adhesion molecule expression may be enhanced by certain fatty acids and inhibited by others, implying an interference with signal transduction processes. Effects of lipoproteins on vasoactive substances seem to be implicated in endothelial dysfunction, too. The endothelium-derived relaxing factor nitric oxide (NO) has gained increasingly attention in the last two decades and is regarded as protective against hypertension and atherosclerosis. It was demonstrated that chylomicrons and their remnants inhibited endothelium-dependent relaxations in isolated aortas. Vasodilatatory responses and nitric oxide metabolism were shown to be affected by the amount and composition of dietary fat. Cell culture experiments revealed modulation of NO release by certain fatty acids. Plasma levels of endothelin-1, a strong vasoconstrictor, have been shown to be increased in patients with type 2 diabetes and metabolic syndrome, respectively. Postprandially elevated triglycerides increased endothelin-levels in addition to insulin in patients with metabolic syndrome. In summary, there is evidence that the association between postprandial triglycerides and the metabolic syndrome is driven by direct influences on endothelial functions because plasma triglyceride levels are associated with levels of humoral risk markers of endothelial origin, and postprandial lipoproteins stimulate the release and/or expression of endothelial mediators in vitro, which induce atherogenesis and hypertension.

Animals↗

Treatment of dyslipoproteinemia in the metabolic syndrome.

The metabolic syndrome consists of a cluster of metabolic disorders, many of which promote the development of atherosclerosis and increase the risk to develop cardiovascular disease. The metabolic syndrome is characterized by atherogenic dyslipidemia (elevated triglycerides, increased small dense low-density lipoproteins, and decreased high-density lipoproteins), hypertension, insulin resistance and obesity. To decrease the risk of cardiovascular disease events decreasing body weight by ingesting a healthy diet, increasing physical activity, cessation of smoking and managing dyslipidemia are recommended. Pharmacological treatment of dyslipidemia is based on different drug classes. For LDL-cholesterol-lowering mainly statins and for triglyceride-lowering mainly fibrates are used. In primary and secondary prevention trials of heart disease they have shown to reduce the incidence of coronary artery disease or coronary events by 25-60 percent. Statins reduce mainly LDL-cholesterol levels by competitive inhibition of HMG-CoA reductase but have also shown to reduce fasting and postprandial triglyceride levels. Fibrates effectively reduce fasting and postprandial lipemia, shift the distribution of LDL particles towards less dense particles and increase HDL-cholesterol. Thus fibrates particularly address components of the metabolic syndrome and features of diabetic dyslipidemia. However studies still are needed showing definite evidence on differential therapy in lipid lowering based on prospective controlled trials with endpoints of macro- and microangiopathy in diabetic patients.

Arteriosclerosis↗

Xenotransplantation of parathyroids in rats using barium-alginate and polyacrylic acid multilayer microcapsules.

The integrity and function of encapsulated parathyroid tissue following xenotransplantation is limited by oxygen and nutrition supply and capsule fibrosis. Since some of these factors depend on stability and biocompatibility of the coating material, multilayer microcapsules have been developed. Parathyroid tissue pieces and digested single cells from pigs were encapsulated in barium-alginate and in polyacrylic acid (PAA) multilayer capsules. After 7 days of culture the function of the encapsulated cells were assessed. Subsequently, in a part of the cultured microcapsules the viability was directly assessed whereas the other part was transplanted in dark animal [DA] rats for 30 days. After explantation viability and fibrotic reaction were examined. Single cells showed a significant increase in parathyroid hormone [PTH] secretion when exposed to medium low in calcium, whereas minced tissue pieces revealed necrosis without stimulatory responsiveness. Morphometry showed significantly better viability of single cells compared with minced tissue in vitro and in vivo. The fibrotic reaction against capsules with minced tissue was more pronounced than for capsules containing single cells. There was no difference between barium alginate and PAA capsules when containing minced tissue. In single cells, however, the fibrous tissue reaction differed significantly between barium alginate and PAA capsules. Encapsulated single cells of parathyroid tissue maintain detectable function and viability. In contrast minced tissue underwent necrosis and induced significantly more connective tissue reaction than single cells indicating an interrelationship between necrosis and fibrosis.

Acrylic Resins↗

Probiotics, prebiotics, and synbiotics--approaching a definition.

Definitions of different pro-, pre-, and synbiotics suggested by different investigators are critically discussed. On the basis of this analysis, the probiotic concept is confined to effects exerted by viable microorganisms but is applicable independent of the site of action and route of administration. It therefore may include sites such as the oral cavity, the intestine, the vagina, and the skin.

Dairy Products↗