Joseph Rafter

Karolinska Institutet | KI · Department of Biosciences and Nutrition

Background Irritable bowel syndrome (IBS) shows genetic predisposition, however, large‐scale, powered gene mapping studies are lacking. We sought to exploit existing genetic (genotype) and epidemiological (questionnaire) data from a series of population‐based cohorts for IBS genome‐wide association studies (GWAS) and their meta‐analysis. Methods B...

Our results provide novel evidence linking faecal microbiota composition to the occurrence of abdominal pain and its frequency, duration and intensity in the general population.

Recently in Gut , genetic variation affecting ion channels activity has been highlighted in relation to bowel function and the biology of stool frequency.1 It is also known that 2% of patients with IBS carry functional missense mutations in the voltage-gated channel NaV1.5 ( SCN5A gene).2 Hence, channelopathies represent potential abnormalities und...

The ligand-induced transcription factor, aryl hydrocarbon receptor (AhR) is known for its capacity to tune adaptive immunity and xenobiotic metabolism—biological properties subject to regulation by the indigenous microbiome. The objective of this study was to probe the postulated microbiome-AhR crosstalk and whether such an axis could influence met...

Objective IBS shows genetic predisposition, but adequately powered gene-hunting efforts have been scarce so far. We sought to identify true IBS genetic risk factors by means of genome-wide association (GWA) and independent replication studies. Design We conducted a GWA study (GWAS) of IBS in a general population sample of 11 326 Swedish twins. IBS...

We read with interest the paper by Rehman et al 1 reporting the contribution of Nod2 genotype to the composition of gut microbiota in mice and Crohn's disease (CD) patients. This was followed by a similar description for another CD-predisposing gene, FUT2.2 To date, 163 CD- and ulcerative colitis-risk loci have been identified, and while most of th...

Mammalian brain development is initiated in utero and internal and external environmental signals can affect this process all the way until adulthood. Recent observations suggest that one such external cue is the indigenous microbiota which has been shown to affect developmental programming of the brain. This may have consequences for brain maturat...

Cyclooxygenase enzymes (COX-1 and COX-2) catalyse the production of prostaglandins from arachidonic acid. Prostaglandins are important mediators in the inflammatory process and their production can be reduced by COX-inhibitors. Endocannabinoids, endogenous analogues of the plant derived cannabinoids, occur normally in the human body. The Endocannab...

Intervention strategies for obesity are global issues that require immediate attention. One approach is to exploit the growing consensus that beneficial gut microbiota could be of use in intervention regimes. Our objective was to determine the mechanism by which the probiotic bacteria Lactobacillus paracasei ssp paracasei F19 (F19) could alter fat...

Probiotic bacteria have been studied for their potential impact on the metabolism of dietary components in the small intestine lumen including lactose digestion, metabolism of lipids such as cholesterol, and oxalate metabolism. In the large intestine, they contribute to the metabolism of otherwise indigestible dietary carbohydrates (e.g., prebiotic...

Probiotic bacteria are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. There is a growing interest in probiotics within the scientific community, with consumers, and in the food industry. The interactions between the gut and intestinal microbiota and between resident and transient microbiota def...

List of genes tested with TLDA, including differentially regulated genes in the livers of SPF compared to GF NMRI mice. (0.09 MB XLS)

The human hepatoma cell line (HepG2) exhibited a dose and time-dependent apoptotic response following treatment with N-Nitrosopiperidine (NPIP) and N-Nitrosodibutylamine (NDBA), two recognized human carcinogens. Our results showed a significant apoptotic cell death (95%) after 24h treatment with NDBA (3.5 mM), whereas it was necessary to use high d...

The initial purpose of this study was to assess the role of estrogen receptor β (ERβ) in intestinal tumorigenesis by examining the effects of an ERβ knockout (ERβ−/−) on ApcMin mice. In order to accomplish this goal on a uniform genetic background, we were required to backcross the ERβ knockout from the 129P2 genetic background to the B6 genetic ba...

The impact of fermented Lactobacillus acidophilus milk on the dietary intake, faecal microflora and faecal bile acids in the aqueous phase was investigated in 14 colon cancer patients. The lactobacillus supplements were given for 6 wk. The number of Escherichia coli decreased in five patients in the colonic microflora, and new colonisation with Kle...

Lactic acid bacteria have been reported to have antimutagenic properties in vitro. In order to investigate whether Lactobacillus acidophilus supplements have antimutagenic effects in humans, 11 healthy subjects on a standardised diet consumed fried beef patties twice daily for 3 d. The diets were supplemented with ordinary Lactococcus fermented mil...

The aim of this work was to determine the effect of vitamin C, diallyl disulfide (DADS) and dipropyl disulfide (DPDS) towards N-nitrosopiperidine (NPIP) and N-nitrosodibutylamine (NDBA)-induced apoptosis in human leukemia (HL-60) and hepatoma (HepG2) cell lines using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. N...

Estrogen receptors (ERs) [ERα (Esr1) and ERβ (Esr2)] are expressed in the human colon, but during the multistep process of colorectal carcinogenesis, expression of both ERα and ERβ is lost, suggesting that loss of ER function might promote colorectal carcinogenesis. Through crosses between an ERα knockout and ApcMin mouse strains, we demonstrate th...

The liver is the central organ for xenobiotic metabolism (XM) and is regulated by nuclear receptors such as CAR and PXR, which control the metabolism of drugs. Here we report that gut microbiota influences liver gene expression and alters xenobiotic metabolism in animals exposed to barbiturates. By comparing hepatic gene expression on microarrays f...

The aim of this study was to evaluate the effect of vitamin C towards N-nitrosopyrrolidine (NPYR)- and N-nitrosodimethylamine (NDMA)-induced apoptosis in human hepatoma (HepG2) and leukemia (HL-60) cell lines using flow cytometry analysis and the terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling assay (TUNEL). None of the vitam...

The cyclooxygenase-2 enzyme (COX-2) is involved in prostaglandin biosynthesis and plays a significant role in the process of inflammation. Several compounds of plant origin affect the COX-2 enzymatic activity [1]. In recent years it has also been suggested that COX-2 is involved in cancer development [2]. Thus, ingested phytochemicals with anti-inf...

A vegetarian diet rich in phytochemicals may prevent colon carcinogenesis by affecting biochemical processes in the colonic mucosa. Compounds passing the digestive system reaching the colon could potentially be detected in fecal water. We previously reported that intact fecal water samples from human volunteers significantly decreased prostaglandin...

The aim of this study was to investigate the protective effects of organosulfur compounds (OSCs) alone or in combination with vitamin C towards N-nitrosopiperidine (NPIP) and N-nitrosodibutylamine (NDBA)-induced oxidative DNA damage in the single cell gel electrophoresis (SCGE)/HepG2 assay. Diallyl sulfide (DAS) did not protect against NDBA-induced...

Separating the large intestine from gut flora is a robust layer of epithelial cells. This barrier is armed with an array of recognizing receptors that collectively set the host innate response. Here, we use nuclear receptors (NRs) and Toll-like receptors (TLRs), suggested to act as second messengers in the communication between microorganisms and e...

This investigation aims at monitoring the formation of diamines in the gastrointestinal tract of human infants, and thereby also the bacterial colonization of the intestine, by studying the urinary excretion of the heterocyclic amine piperidine during development and in different malabsorptive states. A gas chromatographic assay of the dinitropheny...

N-nitrosopiperidine (NPIP) and N-nitrosodibutylamine (NDBA) belong to a group of N-nitrosamines that are widely distributed in foodstuffs and the occupational environment. In the present study, the human promyelocytic leukemia cell line HL-60, was used to characterize the apoptotic effects of N-nitrosamines, and to examine the production of reactiv...

Many phytochemicals found in the diet may prevent colon carcinogenesis by affecting biochemical processes in the colonic mucosa. Inflammation and subsequent elevation of the enzyme cyclooxygenase-2 (COX-2) are two such factors involved in the development of colon cancer, and inhibition of these processes could be important targets for chemopreventi...

The aim of this study was to investigate the protective effect of isothiocyanates alone or in combination with vitamin C towards N-nitrosodibutylamine (NDBA) or N-nitrosopiperidine (NPIP)-induced oxidative DNA damage in the single cell gel electrophoresis (SCGE)/HepG2 assay. Phenethyl isothiocyanate (PEITC) and indole-3-carbinol (I3C) alone showed...

The aim of this study was to investigate the protective effect of vitamin C towards N-nitrosamine-induced DNA damage in the single-cell gel electrophoresis (SCGE)/HepG2 assay. None of the vitamin C concentrations tested (1-10 microM) in presence or absence of formamidopyrimidine-DNA glycosylase (Fpg enzyme) caused DNA damage per se. HepG2 cells sim...

The aim of this study was to investigate the protective effect of organosulfur compounds towards N-nitrosamine-induced DNA damage in the single-cell gel electrophoresis (SCGE)/HepG2 assay. N-Nitrosopyrrolidine (NPYR) and N-nitrosodimethylamine (NDMA) incubated with formamidopyrimidine-DNA glycosylase (Fpg), caused a significant increase in oxidativ...

The aim of this study was to evaluate the effects of organosulfurs, isothiocyanates and vitamin C towards hydrogen peroxide-induced DNA damage (DNA strand breaks and oxidized purines/pyrimidines) in human hepatoma cells (HepG2), using the Comet assay. Treatment with hydrogen peroxide (H(2)O(2)) increased the levels of DNA strand breaks and oxidized...

Animal studies suggest that prebiotics and probiotics exert protective effects against tumor development in the colon, but human data supporting this suggestion are weak. The objective was to verify whether the prebiotic concept (selective interaction with colonic flora of nondigested carbohydrates) as induced by a synbiotic preparation-oligofructo...

The assessment of cellular effects by the aqueous phase of human feces (fecal water, FW) is a useful biomarker approach to study cancer risks and protective activities of food. In order to refine and develop the biomarker, different protocols of preparing FW were compared. Fecal waters were prepared by 3 methods: (A) direct centrifugation; (B) extr...

The aim of this study was to investigate the protective effect of isothiocyanates towards N-nitrosamine-induced DNA damage in the single-cell gel electrophoresis (SCGE)/HepG2 assay. None of the isothiocyanates (ITCs) concentrations tested in the presence or absence of formamidopyrimidine-DNA glycosylase (Fpg), caused DNA damage per se. Combined tre...

The cyclooxygenase-2 enzyme (COX-2) is involved in prostaglandin biosynthesis and thus plays a significant role in the process of inflammation. Different types of natural compounds can affect the COX-2 enzymatic activity [1]. In recent years it has also been suggested that COX-2 is involved in cancer development [2]. As many natural compounds are p...

The microbiota of the human gastrointestinal tract and in particular the large intestine, comprises a large and diverse range of microorganisms, with over¹⁰12 bacteria per gram of contents (1). It is therefore not surprising that the activities of this microbial population have a significant impact on the health of the host. The microbiota interact...

The first results of the Women's Health Initiative dietary intervention trial were published in the USA in February. This is a colossal intervention designed to see if diets lower in fat and higher in fruits, vegetables and grains than is usual in high-income countries reduce the incidence of breast cancer, colorectal cancer, heart disease and othe...

The inducible enzyme cyclooxygenase-2 (COX-2) plays a major role in the regulation of inflammation and possibly in the development of colon cancer. The aim of the present study was to screen for COX-2 inhibitors in samples of fecal water (the aqueous phase of feces) and investigate whether phenolic compounds are responsible for any observed effects...

On August 29-31, 2004, 84 academic and industry scientists from 16 countries gathered in Copper Mountain, Colorado USA to discuss certain issues at the forefront of the science of probiotics and prebiotics. The format for this invitation only meeting included six featured lectures: engineering human vaginal lactobacilli to express HIV-inhibitory mo...

Polyethylene glycol 8000 inhibits the formation of tumors and of aberrant crypt foci (ACF) in carcinogen-initiated rats. We asked: is the inhibition associated with a reduction of colonic inflammation and an increase in colonic cell permeability? Twenty-eight, male F 344 rats were divided into two groups, 10 control animals and 18 animals initiated...

Phenolic compounds are not completely absorbed in the small intestine and so enter the colon, where they might exert physiological effects. To identify phenolics that are present in normal human colon, fecal water was prepared from 5 free-living volunteers with no dietary restrictions and analyzed by gas chromatography-mass spectrometry. Daily meas...

Although there is considerable evidence that high consumption of red meat may increase the risk of colorectal cancer, data by subsite within the colon are sparse. The objective of our study was to prospectively examine whether the association of red meat consumption with cancer risk varies by subsite within the large bowel. We analyzed data from th...

The aqueous phase of feces (fecal water) has been suggested to mediate the effects of diet on colon carcinogenesis. We determined whether human fecal water samples, of varying genotoxic potential, had the capacity to alter adhesion of intestinal bacteria to intestinal (Caco-2) cells. Genotoxicity of fecal water samples was measured using the single...

Foods and beverages rich in phenolic compounds, especially flavonoids, have often been associated with decreased risk of developing several diseases. However, it remains unclear whether this protective effect is attributable to the phenols or to other agents in the diet. Alleged health-promoting effects of flavonoids are usually attributed to their...

While several effects beneficial to health have been attributed to the probiotic lactic acid bacteria, perhaps the most interesting and controversial remains that of anti-cancer activity. The vast majority of studies in this area deal with protective effects against colon cancer. There is no direct experimental evidence for cancer suppression in hu...

The role of dietary factors in the aetiology of human cancer is an area, which has attracted intense interest in recent years. The suggestion that approximately one third of all cancers may be caused by an 'inappropriate' balance of food components has led to the attractive contention that we can significantly decrease cancer incidence through diet...

The UK Food Standards Agency convened a group of expert scientists to review current research investigating emerging diet-related surrogate end points for colorectal cancer (CRC). The workshop aimed to overview current research and establish priorities for future research. The workshop considered that the validation of current putative diet-related...

The nuclear hormone receptor peroxisome proliferator-activated receptor (PPAR) gamma plays an important role in the differentiation of intestinal cells and other tissues. Real-time PCR examination of PPAR mRNA for gamma1, gamma2 and gamma3, in Caco-2 and HCT-116 colon cell lines showed that gamma3 is the most abundant message in both lines. Treatme...

Although a myriad of health-promoting effects have been attributed to the probiotic lactic acid bacteria, perhaps the most interesting and controversial is that of anticancer activity, the vast majority of studies in this area dealing with protective effects against colon cancer. There is no direct experimental evidence for cancer suppression in hu...

Inulin, polydisperse beta (2-1) fructan, has been suggested to protect against colon carcinogenesis and is currently used in a number of food applications. However, the data regarding the role of inulin in intestinal carcinogenesis remains controversial since the results of our previous study suggested that inulin promotes intestinal tumor formatio...

The free water phase of feces (fecal water) may mediate the effects of diet on colon carcinogenesis. We examined the effects of fecal water from adenoma patients and controls on three parameters in colonocytes believed to be relevant to tumorigenesis, i.e. genotoxicity in intact cells and on isolated DNA, proliferative activity and activator protei...

Consumption of probiotic bacteria such as bifidobacteria has been shown to reduce the risk of colon cancer in animal models. However, the composition and metabolic activities of the intestinal flora of experimental animals are significantly different from those of humans. The aim of the study was to examine whether the probiotic mixture, which cons...

One of the most promising areas for the development of functional foods lies in modification of the activity of the gastrointestinal tract by use of probiotics, prebiotics and synbiotics. While a myriad of healthful effects have been attributed to the probiotic lactic acid bacteria, perhaps the most controversial remains that of anticancer activity...

Recently, we described a new in vivo pathway in the metabolism of benzo[a]pyrene (BP) that involves an opening of the aromatic ring system. One of the products of this pathway, isolated from rat urine, was the anhydride of 7-oxo-benz[d]anthracene-3,4-dicarboxylic acid (ABADA). We have now investigated the effect of ABADA on several cellular targets...

Colorectal cancer is one of the most important causes of cancer morbidity and mortality in Western countries. While a myriad of healthful effects have been attributed to the probiotic lactic acid bacteria (LAB), perhaps the most controversial remains that of anticancer activity. It should be pointed out that there is no direct experimental evidence...

Evidence is accumulating that bile acids induce apoptosis in colonic cells. Therefore, it becomes important to study the underlying molecular mechanisms and the role of this phenomenon in tumor promotion. Minutes after exposure of HCT 116 and HT-29 cells to deoxycholate (DCA), DNA damage, measured using the COMET assay, was evident. Caspase-3 was r...

Lactic acid bacteria have been reported to have antimutagenic and anticarcinogenic properties in vivo and in vitro. Lactobacillus acidophilus and Bifidobacterium longum have earlier been shown to bind the food mutagen Trp-P-2 in vitro. The influence of oral supplementation with L. acidophilus NCFB 1748 and B. longum BB 536 on the uptake and distrib...

Diesel fuels, classified as environmentally friendly, have been available on the Swedish market since 1991. The Swedish diesel fuel classification is based upon the specification of selected fuel composition and physical properties to reduce potential environmental and health effects from direct human exposure to exhaust. The objective of the prese...

Evidence is accumulating that inhibitors of cyclooxygenase (COX)-2 activity are useful for preventing human colon cancer. Therefore, it is important to determine whether agents in the colonic luminal contents can influence the transcriptional regulation of COX-2 in colonic cells. Transient transfections were performed, using a human COX-2 promoter-...

The metabolism of benzo[a]pyrene (BP) is known to lead to a large number of oxygenated compounds, some of which can bind covalently to DNA. We have studied the integrated metabolism of BP in vivo in germ-free rats given (14)C-labeled BP. Urinary metabolites were separated into groups according to acidity using lipophilic ion exchangers. The groups...

While a myriad of healthful effects have been attributed to the probiotic lactic acid bacteria, perhaps the most controversial remains that of anticancer activity. There is no direct experimental evidence for cancer suppression in humans as a result of consumption of lactic cultures in fermented or unfermented dairy products. However, there is a we...

Although the intestinal flora is believed to have a critical role in carcinogenesis, little is known about the role of the human intestinal flora on the effects of mutagens in vivo. The aim of the present study was to address a possible role of the human intestinal flora in carcinogenesis, by exploiting human-flora-associated (HFA) mice. The capaci...

cDNA representational difference analysis (cDNA RDA) is a PCR-based subtractive enrichment procedure for the cloning of differentially expressed genes. In this study, we have further developed the procedure to take advantage of solid-phase technology, and to facilitate the use of RDA when starting material is limited. Several parameters of the PCR-...

Colorectal cancer is one of the most important causes of cancer morbidity and mortality in western countries [1]. A myriad of healthful effects have been attributed to the probiotic lactic acid bacteria; perhaps the most controversial remains that of anticancer activity. There is no direct experimental evidence for cancer suppression in humans as a...

Knowledge regarding the expression of the recently cloned estrogen receptor beta (ERbeta) in colonic mucosa is limited. In this study, we demonstrated that five human colon cancer cell lines, HT29, Colo320, Lovo, SW480, and HCT116, expressed ERbeta mRNA, but lacked ERalpha mRNA. Results from a cell growth assay demonstrated that these colon cancer...

Apoptosis is central to cell number regulation in the colonic epithelium, and interest in its role in colon carcinogenesis has been growing rapidly. It thus becomes of interest to characterize luminal components, possibly of dietary origin, that may influence this process. We have investigated the sensitivity of two human colonic cell lines, the hu...

At last, inroads are beginning to be made into the hitherto unknown and complex area of gene-environment interactions in the colon. Interestingly, many of the studies to date would suggest: that the Apc gene is a target for such interactions; that luminal factors can regulate the level of cellular proteins of central importance in the control of ce...

The characterization of conjugated metabolites of benzo[a]pyrene (BP) in the urine of male germ-free rats given a single intraperitoneal dose of [(14)C]BP is described. Urinary metabolites, constituting 9% of the administered radioactivity, were extracted on a Sep-Pak C(18) cartridge and separated by lipophilic ion-exchange chromatography into neut...

In the multistage model of human colorectal tumorigenesis, both genetic and environmental factors play an important role. The identity of the environmental factors involved, however, still remains to be elucidated. As fecal bile acids are proposed as candidates, we compared the concentration of bile acids in fecal water from patients at different r...

Colorectal cancer is one of the most important causes of cancer morbidity and mortality in Western countries. While a myriad of healthful effects have been attributed to the probiotic lactic acid bacteria, perhaps the most controversial remains that of anticancer activity. It should be pointed out already at this point that there is no direct exper...

We recently suggested that prolonged deregulated expression of AP-1 activity in colonic cells by bile acids may contribute to tumour promotion in the colon. In the present study, using two human colon carcinoma cell lines, HT-29 and HCT 116, transiently transfected with the AP-1-luciferase reporter construct, we showed that the bile acids, deoxycho...

ECNIS is a Network of Excellence within the European Union’s Sixth Framework Programme, Priority 5: Food Quality and Safety. It brings together some of the best European research groups in a concerted effort to achieve improved understanding of the environmental causes of cancer, of the potential of diet to prevent cancer and of the ways in which h...

Colorectal cancer is now widely accepted to be the result of an accumulation of mutations in specific genes controlling cell division, apoptosis and DNA repair. There is also a wealth of evidence that dietary factors, including dietary fat and fibre, influence the development of colorectal cancer. However, until recently, there has been little unde...

Nano-electrospray has been used in combination with high resolution and tandem mass spectrometry in the analysis of the major mercapturic acid pathway metabolites of benzo[a]pyrene (BP). Accurate mass measurements indicate that the [M-H]- ion of the major metabolite has a chemical formula C25H22NO6S, which corresponds to the deprotonated form of te...

Toxic agents, particularly those that exert their actions with a great deal of specificity, sometimes act via receptors to which they bind with high affinity. Some examples of soluble intracellular receptors, which are important in mediating toxic responses, are discussed in this paper. The first example is the glucocorticoid receptor, which can ac...

Human faecal waters from 35 healthy non-smoking volunteers (23 from England and 12 from Sweden) consuming their habitual diet were screened for genotoxicity by the single-cell gel electrophoresis (comet) assay using a human colon adenocarcinoma cell line (CACO-2) as the target. Hydrogen peroxide induced DNA damage was categorized as low, intermedia...

Several epidemiologic studies have suggested that dairy product intake is associated with a decreased incidence of colon cancer. To determine whether the cytotoxicity and genotoxicity of the aqueous portion of human stool (two potential risk markers for the disease) were affected by a change in dairy product intake, 18 healthy male and female volun...

Chemical fractions of a model diesel exhaust particulate extract, notably the fraction containing polycyclic aromatic hydrocarbons (PAH) (Fraction II), mono-nitro PAH (Fraction III), and dinitro-PAH (Fraction IV) have been shown to displace binding of 2,3,7,8-tetrachloro[1,6-[3H]]dibenzo-p-dioxin (TCDD) from the rat liver cytosol aryl hydrocarbon (...

Benzo[a]pyrene (BP) metabolites conjugated with glutathione, cysteine-glycine, cysteine, N-acetylcysteine, and sulfuric and glucuronic acids have been studied by microcolumn liquid chromatography-electrospray mass spectrometry with collision-induced dissociation (CID) on a hybrid double focusing magnetic sector-orthogonal time-of-flight tandem mass...

Isomeric forms of the mercapturic acid pathway metabolites of benzo[a]pyrene (EP) tan be differentiated by positive-ion electrospray collision-induced dissociation (CID) mass spectrometry at the nanogram level, The metabolite (+)-r-7,t-8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE), conjugated at position 10 (bay region) with cys...

Polycyclic aromatic compounds and dioxin receptor ligands present in diesel particulate extract fractions and subfractions were determined. A crude model diesel particulate extract was fractionated into five fractions (I–V), fractions I, II and III were further fractionated into subfractions (I-1, I-2, II-1 to II-7 and III-1 to III-6). The amounts...

The peroxisome proliferator-activated receptor (PPAR), a member of the steroid nuclear receptor superfamily, has been shown to be activated by various compounds such as fibrates, thiazolidinediones, prostaglandins, and fatty acids. Here we demonstrate expression of PPAR in mouse colonic and small intestinal mucosa by Western blot analysis and immun...

To further understand the molecular mechanisms of bile acid-mediated colon tumor promotion, we have examined the possible role of AP-1 activity in this process. The AP-1 complex has been reported to play an important role in control of cell growth. Our studies show that lithocholate, deoxycholate and ursodeoxycholate exhibited marked proliferative...

The emission of diesel exhaust particulates is associated with potentially severe biological effects, e.g., cancer. The aim of the present study was to apply multivariate statistical methods to identify factors that affect the biological potency of these exhausts. Ten diesel fuels were analyzed regarding physical and chemical characteristics. Parti...

The phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (160 nM) and the secondary bile acid, deoxycholic acid (50 microM) stimulated DNA synthesis in quiescent primary epithelial cells from the normal mouse colon as measured by autoradiographic analysis of [3H]thymidine incorporation. The purpose of this present study was to investigate the involv...

Lactic acid bacteria have been reported to have antimutagenic/anticarcinogenic properties in vitro and in vivo. One possible mechanism for this effect involves a physical binding of the mutagenic compounds to the bacteria. The purpose of the present investigation was to study the binding capacity of eight human intestinal or lactic acid bacterial s...