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PubMedDate not supplied

[ENCAPSULATED CORD METHOD(Enterotest) COMPARED WITH FECALTEST ON THE DIAGNOSIS OF CRIPTOSPORIUM Sp E ISOSPORA belli In HIV(+)Patients with Gastrointestinal Symptoms]

Fecal samples and small intestinal content obtained by Enterotest were submitted between December 1994 and January 1996, by HIV (+) patients with gastrointestinal symptoms.Unconcentrated and concentrated fecal samples (by Sheater, Ritchie and Spontaneous Sedimentation) and intestinal content obtained by Enterotest, all stained by modificated Ziehl-Nielsen method, were compared (multiatributive comparison) based on the following parameters: yield, each test cost, morphology and the number of parasites per slide, in order to diagnose Cryptosporidium spp. e Isospora belli.Intestinal content obtained by Enterotest on the diagnosis of Cryptosporidium spp. e Isospora belli was not better than the fecal samples but it is more expensive. However, it reached a good diagnostic yield with adequate morphology, and a number of parasites per slide. Furthermore, it can be used as a second line diagnostic method (first line = fecal samples) and as an alternative in places where the use of endoscopy is not available.

Journal Article↗
PubMedDate not supplied

Reduction of fecal shedding and egg contamination of Salmonella enteritidis by increasing the number of heterophil adaptations.

Serial passage of Salmonella enteritidis (SE) in chicken heterophils resulted in heterophil-adapted SE (HASE). We now report that an additional five heterophil passages have further reduced the number and frequency of fecal shedding of HASE. Eleven-times HASE (11 x HASE) given to 12 laying hens for three consecutive days reduced fecal shedding of 11 x HASE to three isolations from fecal samples during the 70-day postexposure observation period. Hens were exposed to challenge SE 74 days after treatment with 11 x HASE. Three of 12 11 x HASE-treated hens were positive for challenge SE (11/396 fecal samples, or 2.8%) between days 5 and 40 postchallenge, whereas all 12 challenge control birds were positive (118/420 fecal samples, or 28.1%) for SE. None of 12 11 x HASE-treated hens was fecal positive from day 9 postchallenge, whereas 10 of 12 challenge control hens (82/372 fecal samples, or 22.0%) remained positive until day 40, the termination of the experiment. None of 525 eggs and eggshells cultured after 11 x HASE exposure was positive for Salmonella, and none of 422 eggs and eggshells cultured after challenge SE exposure was positive for Salmonella. Eggs or eggshells from challenge control hens were positive for Salmonella in 12/479 (2.5%) cases after challenge SE exposure.

Animals↗
PubMed2004

Administration of oral probiotic bacteria to pregnant women causes temporary infantile colonization.

BACKGROUND: It is difficult to permanently change the composition of the complex intestinal microflora of the adult. Orally administered probiotic bacteria produce only temporary colonization of the intestine in patients with a fully developed gut microflora. The gastrointestinal tract of a healthy fetus is sterile. During the birth process and rapidly thereafter, microbes from the mother and the surrounding environment colonize the gastrointestinal tract until a dense, complex microflora develops. Probiotic bacteria have been shown to beneficially influence the intestinal and systemic immune system and mediate protection against nosocomial infections affecting the neonate. OBJECTIVES: The purpose of this study was to determine whether oral administration of the probiotic micro-organism Lactobacillus rhamnosus strain GG (L. GG) to the pregnant woman leads to colonization of the newborn infant. METHODS: The authors identified six women who were taking L. GG during late pregnancy. None of the children received L. GG after birth, and their mothers discontinued its consumption at the time of delivery. L. GG concentration in fecal samples was determined by colony morphology and molecular analysis. RESULTS: In all four children delivered vaginally and in one of two children delivered by cesarean section, L. GG was present in fecal samples at 1 and 6 months of age. Three children remained colonized for at least 12 months, and in two children L. GG was detected in fecal samples at 24 months of age. Three mothers were tested 1 month post partum and no L. GG was present in fecal samples. No L. GG was found in one of these women 24 months post partum. There was no L. GG detectable in stools of the siblings of two children at the 2-year and 3-years after birth of the index child. L. GG was not isolated from the stools of children whose mothers were not taking L. GG. CONCLUSIONS: Temporary colonization of an infant with L. GG may be possible by colonizing the pregnant mother before delivery. Colonization is stable for as long as 6 months, and in unexplained circumstances may persist for as long as 24 months.

Administration, Oral↗
PubMed2004

Prevalence of parasite eggs (Strongyloides westeri, Parascaris equorum, and strongyles) and oocysts (Emeria leuckarti) in the feces of Thoroughbred foals on 14 farms in central Kentucky in 2003.

Prevalence of internal parasites was determined by fecal examination for eggs and oocysts in Thoroughbred foals in central Kentucky in 2003. Fecal samples were examined from 733 foals on 14 farms. This included 70 trips to the farms and a total of 2,346 fecal samplings. Monthly collection of fecal samples was begun for four farms in February, six in March, three in April, and one farm in May. Termination of the study for all farms was the end of July. A criterion was that the foals be at least 10 days old for initial samplings. If available, the same foals were sampled each time, in addition to foals born in the interim between farm visits. Ages of the foals for the complete study varied from 10 to 223 days. Prevalence (mean %) was determined for eggs of Strongyloides westeri (1.5%), Parascaris equorum (22.4%), and strongyles (27.6%) and for oocysts of Eimeria leuckarti (41.6%) in feces of foals. Foals had infections of S. westeri on six farms (42.9%), of P. equorum on 12 farms (86%), and of strongyles and E. leuckarti on all 14 farms (100%).

Animals↗
PubMed2004

Prevalence and characterization of shiga toxin-producing Escherichia coli in swine feces recovered in the National Animal Health Monitoring System's Swine 2000 study.

A study was conducted to determine the prevalence of Shiga toxin-producing Escherichia coli (STEC) in swine feces in the United States as part of the National Animal Health Monitoring System's Swine 2000 study. Fecal samples collected from swine operations from 13 of the top 17 swine-producing states were tested for the presence of STEC. After enrichment of swine fecal samples in tryptic soy broth, the samples were tested for the presence of stx1 and stx2 by use of the TaqMan E. coli STX1 and STX2 PCR assays. Enrichments of samples positive for stx1 and/or stx2 were plated, and colony hybridization was performed using digoxigenin-labeled probes complementary to the stx1 and stx2 genes. Positive colonies were picked and confirmed by PCR for the presence of the stx1, stx2, or stx2e genes, and the isolates were serotyped. Out of 687 fecal samples tested using the TaqMan assays, 70% (484 of 687) were positive for Shiga toxin genes, and 54% (370 of 687), 64% (436 of 687), and 38% (261 of 687) were positive for stx1, stx2, and both toxin genes, respectively. Out of 219 isolates that were characterized, 29 (13%) produced stx1, 14 (6%) produced stx2, and 176 (80%) produced stx2e. Twenty-three fecal samples contained at least two STEC strains that had different serotypes but that had the same toxin genes or included a strain that possessed stx1 in addition to a strain that possessed stx2 or stx2e. The STEC isolates belonged to various serogroups, including O2, O5, O7, O8, O9, OX10, O11, O15, OX18, O20, O57, O65, O68, O69, O78, O91, O96, O100, O101, O120, O121, O152, O159, O160, O163, and O untypeable. It is noteworthy that no isolates of serogroup O157 were recovered. Results of this study indicate that swine in the United States harbor STEC that can potentially cause human illness.

Animals↗
PubMed2005

Sampling effort/frequency necessary to infer individual acute stress responses from fecal analysis in Greylag geese (Anser anser).

Measuring hormone metabolites from excreta is a powerful method to study hormone-behavior relationships. Currently, fecal corticosterone metabolite concentrations are used to estimate individual short-term stress responses. From the free-roaming, semitame flock of greylag geese (Anser anser), as many fecal samples as possible were collected over 3 h following a challenge (social density stress) or in a control situation. This time span corresponds to the gut passage time of geese. It was asked how many samples were necessary to determine differences in excreted corticosterone immunoreactive metabolites (CORTs) between control and social density stress and which parameters (means, maxima, range) reliably showed this difference. A large variation of CORT was found between consecutive samples. Still, means, maxima, and ranges of the samples in a fecal series consistently showed the response to a stressor both within and between individuals. Three samples sufficed if the maximum value of CORT was used, whereas four or more samples were necessary to work with the mean. It was concluded that by increasing the number of fecal samples collected, the course of CORT could be measured more precisely and an individual's acute stress response inferred more reliably.

Animals↗
PubMedDate not supplied

Rapid coagglutination test for detection of rotaviruses in turkeys.

Avian rotaviruses present in fecal samples were readily detected using a staphylococcal protein-A coagglutination test on a white porcelain plate. Staphylococci, which produced large amounts of protein-A, were coated with rabbit anti-avian rotavirus serum. The antibody-coated staphylococci were agglutinated specifically by rotavirus present in the fecal sample. The macroscopic agglutination reaction occurred within a few minutes. A total of 40 fecal samples were tested by the coagglutination test. The sensitivity and specificity of the coagglutination test were compared with those of electron microscopy, enzyme-linked immunosorbent assay, and tissue-culture virus-isolation methods. Of the 31 fecal samples positive for rotavirus on electron microscopy, 27 (87%) were positive on coagglutination test. Of the nine electron-microscopy-negative samples, seven (78%) were also negative on coagglutination test. It was concluded that the staphylococcal protein-A coagglutination test can be used as a simple, rapid screening test for avian rotavirus.

Agglutination Tests↗
PubMed2004

Lack of evidence for reovirus infection in tissues from patients with biliary atresia and congenital dilatation of the bile duct.

BACKGROUND/AIMS: To clarify the association between the reovirus infection of the hepatobiliary tree and the development of infantile obstructive cholangiopathy (IOC) including biliary atresia (BA) and congenital dilatation of the bile duct (CBD). METHODS: We designed reovirus common primers for nested RT-PCR based on the L3 gene segment. The spectrum and the sensitivity of common primers were evaluated with purified reoviral RNAs and reovirus mixed with stool samples. Then, nested RT-PCRs were performed with hepatobiliary and fecal samples obtained from patients with BA, CBD, and control diseases. Additionally, electron microscopy of stool samples was performed. RESULTS: The L3 common primers could amplify cDNAs synthesized from RNAs of three prototypes of reovirus, and detect as much as 5.0x10(3) plaque forming unit of serotype 3 Dearing strain in 100 mg of fecal samples. However, no amplification product was detected in 136 hepatobiliary tissues taken from 67 patients including 26 BAs and 28 CBDs, or in 65 fecal samples obtained from 15 patients including 10 BAs and 1 CBD. Additionally, viral particles were not found in any stool specimens by the electron microscope. CONCLUSIONS: These data do not suggest that reoviruses play a major role in the etiology of IOC or BA.

Bile Ducts↗
PubMed1983

Detection of rotavirus in horses with and without diarrhea by electron microscopy and Rotazyme test.

A total of 142 equine fecal samples (93 field fecal and 49 experimental fecal specimens) were examined for rotavirus using direct electron microscopy (EM) and the Rotazyme test. Eighty-six stool specimens were diarrhea samples. The Rotazyme test sensitivity and accuracy as compared to EM was determined by the visual (color reaction) and spectrophotometric methods. The overall agreement was 94.8% and 92.3% between EM and Rotazyme visual and spectrophotometric methods, respectively when suspect reactions (1 + color reaction or net absorbance between 0.05 and 0.1) were not included. The Rotazyme test is a quick, simple, and accurate diagnostic test for detection of rotavirus in equine fecal samples. It could be used by the equine practitioner with a minimum of laboratory facilities and by diagnostic and research laboratories.

Animals↗
PubMed1985

Enumeration and activity of cellulolytic bacteria from gestating swine fed various levels of dietary fiber.

Cellulolytic bacteria were enumerated and cellulase activity was determined over a 98-day period from fecal samples of gestating swine fed various levels and sources of fiber. The diets, each fed to five pigs, were a corn-soybean control, 20% corn cobs, and 40 and 96% alfalfa meal. Fecal samples were collected from all pigs on days 0, 5, 14, 21, 35, 49, 70, and 98. Overall, the most probable number of cellulolytic bacteria from pigs fed the control, 20% corn cobs, and 40 and 96% alfalfa meal was 23.3 X 10(8), 15.2 X 10(8), 45.1 X 10(8), and 52.5 X 10(8) per g (dry weight) of fecal sample, respectively. Enumeration of cellulolytic bacteria by counting zones of clearing in roll tubes, as compared with the most probable number procedure, accounted for only 1.1 and 17.0% of the cellulolytic bacteria, respectively, from pigs fed the control or 96% alfalfa meal diet. Cellulolytic bacteria (most probable number) on days 70 and 98 accounted for 4.1 and 10.0% of the viable count for the pigs fed the control and 96% alfalfa meal diets, respectively. The viable count was not different between pigs fed the control and 96% alfalfa meal diets. The overall mean cellulolytic activity (milligrams of glucose released from carboxymethyl cellulose per gram [dry weight] fecal sample per 30 min was 17.0, 19.9, 23.8, and 20.6, respectively, for the control, 20% corn cobs, and 40 and 96% alfalfa meal diets. The results indicate that the cellulolytic flora can be increased by prolonged feeding of high-fiber diets and may represent 10% of the culturable flora.

Animals↗
PubMed2005

Evaluation of silymarin in the treatment on asymptomatic Giardia infections in dogs.

We have reported previously the efficacy of antiprotozoal drugs against canine giardiasis (In press, Journal of Veterinary Clinic, the Korean Society of Veterinary Clinics). Fenbendazole was found to be the most efficacious for the treatment of canine giardiasis. There were no significant differences between the efficacy of albendazole and fenbendazole against canine giardiasis. On the other hand, the efficacy of metronidazole for the treatment of canine giardiasis, the efficacy was lower when compared to that of albendazole and fenbendazole. On the basis of these results, to evaluate clinical effect of silymarin, we evaluated the therapeutic efficacy of metronidazole alone, or combined with silymarin for 2 weeks for canine giardiasis. In addition, to observe effects on nutrition, we investigated the changes of body weight, the serum biochemical indicators for liver inflammation (GOT, GPT, NH3), the liver cell regeneration indicators (total protein, albumin) and the hematological changes during treatment (WBC, RBC, MCV, MCH and MCHC). The dogs were allocated to four groups; one group was treated with silymarin (3.5 mg/kg once a day, oral), another with metronidazole (50 mg/kg once a day, oral), and the other group with silymarin (3.5 mg/kg once a day, oral) plus metronidazole (50 mg/kg once a day, oral), while control group remained nontreated. The fecal samples from all the dogs were examined, using the ZSCT and giardia antigen test kit (SNAP(*) Giardia, IDEXX Laboratories), from each dog of each group for three times a week for 2 weeks. Dogs were considered to have giardiasis when one or more of the fecal samples had positive results for Giardia cysts. Seven days after treatment, the efficacy of silymarin plus metronidazole was found 79%, whereas that of metronidazole was 72%. Ten days post-treatment the efficacy of metronidazole plus silymarin (91%) was significantly different in comparison with that of metronidazole (75%). Two weeks post-treatment no cysts were detected in the fecal samples in the dogs of metronidazole or silymarin plus metronidazole-treated groups. Whereas, the fecal samples of all the dogs of the control and only silymarin-treated groups were giardia positive. Signs of side effects were not observed in silymarin plus metronidazole-treated dogs. But poor appetite and intermittent vomiting signs were observed in two dogs of the metronidazole-treated group that resolved when metronidazole administration was discontinued. The body weight of those treated with metronidazole was significantly decreased in comparison with those treated with silymarin and metronidazole plus silymarin. There were significant differences of body weight between the dogs treated with silymarin and metronidazole. Two weeks after metronidazole treatment, serum concentration of GOT, GPT and NH3 were significantly increased in comparison with those treated with silymarin. On the other hand, the serum concentration of GOT, GPT and NH3 were not significantly increased when treated with silymarin plus metronidazole compared to those treated with metronidazole. Serum total protein and albumin concentrations were decreased after metronidazole treatment as compared to those treated with silymarin and silymarin plus metronidazole. The concentrations of serum total protein and albumin decreased significantly in metronidazole-treated group as compared to that of treated with silymarin. The numbers of WBC and RBC did show significant differences in the dogs treated with metronidazole, while MCV, MCH were significant by different between silymarin and metronidazole-treated dogs. On the other hand, there were no significant differences in MCHC in any groups. These data suggest that silymarin, in supplement with antiprotozoal drugs, can influence the therapy of canine giardiasis.

Administration, Oral↗
PubMed1989

Recovery of fecal chromium used as a digestibility marker in cattle.

Chromium content of fecal samples that were mixed with Cr-mordanted rumen contents at 5 or 10 g/200 g feces in Experiment 1 and at 5 or 10 g/300 and 200 g feces in Experiment 2 was determined by atomic absorption spectroscopy. Recovery of Cr was estimated after digesting fecal samples, which were frozen fresh and later thawed or dried in either a forced draft oven at 60 degrees C or in a microwave oven in Experiment 1. Experiment 2 evaluated the efficacy of each of three methods of digestion in recovery of Cr from fecal samples. Recoveries of Cr from feces were calculated relative to the Cr content of the Cr-mordanted rumen contents, which were determined by atomic absorption spectroscopy of samples digested with concentrated nitric acid in the presence or absence of the wetting agent Tween 80. Recovery of Cr from fecal samples frozen fresh and later thawed was greater than that from either forced draft oven or from microwave oven-dried samples, especially when the concentrated nitric acid digestion was used. Neither the double ashing procedure nor the digestion with the weaker nitric acid did not improve Cr recoveries from the samples.

Animals↗
PubMed1998

Immunofluorescence test on Schistosoma mansoni worm paraffin sections (IgM-IFT) for the study of schistosomiasis transmission in Campinas, São Paulo, Brazil.

The detection of IgM antibodies for Schistosoma mansoni using gut-associated antigens (IgM-IFT) was compared to the parasitological Kato-Katz method for study of the transmission of schistosomiasis in an urban area in Campinas. About 400 schoolchildren whose ages ranged from 6 to 18 years, were observed for a period of two years. Blood samples on filter paper and fecal samples were collected, at intervals of six months. Serological (IgM-IFT) prevalence rates of 1.2%, 4.3%, 3.6%, 2.9% and 3.4% were obtained in five surveys carried out. S. mansoni eggs were detected in only one child out of the 225 children (0.4%) who were submitted to the Kato-Katz method (three slides for each fecal sample) in the 1st survey. Sixty eight children who submitted five blood samples, one for each survey, were found IFT negative throughout the study. No child was found to be IFT positive in all five surveys, and only four children showed IFT positive results in at least four surveys. Seroconversion from IFT negative to positive was observed from the 1st to the 2nd survey in six children, from the 2nd to the 3rd survey in three children, from the 3rd to the 4th survey in four children, and from the 4th to the 5th survey in two cases. However, confirmation of S. mansoni infection using the fecal examination was not possible in any of the cases. Also, in most of them the IFT result oscillated from negative to positive and vice versa. Our data implied that recent transmission of schistosomiasis in the study area was not possible.

Adolescent↗
PubMed1990

Removal of inhibitory substances from human fecal specimens for detection of group A rotaviruses by reverse transcriptase and polymerase chain reactions.

A method was developed for the purification of rotavirus RNA from fecal extracts in order to permit the sensitive identification of group A rotavirus in fecal specimens by the polymerase chain reaction. Sequential reactions with reverse transcriptase and Taq polymerase with directed primers from rotavirus gene 6 yielded characteristic 259-base-pair fragments that were then visualized by silver stain on a polyacrylamide gel. As few as 500 genomic copies of purified rotavirus RNA could be detected in this manner. However, when the method was applied to fecal samples with added rotavirus virions, inhibition was noted in many of the fecal extracts which were tested. The inhibition could be reversed by dilution of the fecal extract, but sensitivity was also reduced by a corresponding dilutional factor. The inhibition was quantitatively removed by an added step in the extraction process that utilized chromatographic cellulose fiber powder (CF11 powder) to purify the rotavirus RNA during a series of rapid washing and elution steps. After CF11 purification, rotavirus RNA could be detected in experimental fecal samples at dilutions 1,000- to 10,000-fold beyond the detection limits of standard techniques such as enzyme immunoassay and the direct visualization of RNA following polyacrylamide gel electrophoresis. Furthermore, following purification by CF11, rotavirus RNA could be detected in all of seven enzyme-linked immunosorbent assay-positive fecal samples obtained from a child with rotavirus gastroenteritis; when CF11 purification was not performed, rotavirus RNA could be detected in only four of these samples, even after the removal of inhibitors by dilution of the extracts. Large-scale identification of rotavirus in fecal specimens may be possible by use of CF11 purification of viral RNA prior to sequential reactions with reverse transcriptase and Taq polymerase in a modified polymerase chain reaction.

Feces↗
PubMed2005

Prevalence of Salmonella spp. on Canadian pig farms using liquid or dry-feeding.

The objective of this study was to determine whether the shedding and antibody titre to Salmonella was lower for pig herds provided liquid-feed compared to those on traditional dry rations. Twenty liquid-feeding farms and 61 dry-feeding farms were selected. The amount of antibodies to Salmonella in sera from 15 finisher pigs on each of 80 Ontario swine farms was analyzed by means of enzyme-linked immunosorbent assay (ELISA). In addition, the presence of Salmonella on the 20 liquid-feeding farms and 21 of the dry-feeding farms was assessed by culture of 15 fecal samples taken directly from finisher pigs and five pooled pen-fecal samples at each farm. A cut-off of OD% 10 was used. The Salmonella sero-prevalence differed between the two groups of farms. At least one pig tested sero-positive on 98% of the dry-feeding farms and 84% of the liquid-feeding farms (P<0.05). A multi-variable mixed linear regression model with the farm as a random variable and farm factors as the fixed effects was fitted. Crude optical density (OD) of the individual pig was considered as the continuous dependent variable. Dry-feeding and antimicrobial daily usage was associated with crude OD (P<0.05). In addition, crude OD increased with increasing herd size (P<0.05). Salmonella was isolated from 25 out of 420 fecal samples (6%) from dry-feeding farms compared to three out of 400 samples (0.8%) from liquid-feeding farms. Eight of the dry-feeding farms (38%) tested positive compared to only three of the liquid-feeding farms (15%). Salmonella was also recovered from the pen environment on five dry-feeding farms but were not isolated from the facilities using liquid-feeding. Salmonella Typhimurium was isolated from four farms in the dry-feed group and on one farm with liquid-feeding. The one S. Typhimurium isolate from the liquid-feeding farm exhibited no antimicrobial resistance, but those from dry-feeding farms were resistant to four or more antimicrobial agents. The results of the logistic regression, with farm as a random effect showed that dry-feeding [OR=2.7 (1.1-15.1)] and continuous flow system [OR=2.3 (1.2-12.7)] increased risk of finding Salmonella in the individual pig. These findings indicate that liquid-feeding and all-in all-out management of the grower-finisher barns can reduce the Salmonella prevalence.

Animal Feed↗
PubMed1997

[Trial for isolation of Helicobacter pylori form fecal specimen by immunomagnetic beads separation].

In order to clarify the possibility of feco-oral transmission of Helicobacter pylori, we have employed an immunomagnetic beads (IMB) separation technique and tried to isolate H. pylori from fecal samples. Microaerophilic cultivation and PCR of H. pylori were positive when H. pylori (10(3) cfu) was suspended in Hanks' balanced salt solution (HBSS) for the IMB separation technique. In contrast, when a lower number of H. pylori (10(2) cfu) was suspended in HBSS, 2nd PCR was positive but cultivation was negative. After IMB separation technique from fecal sample containing H. pylori (2 x 10(4) cfu), 20 cfu of H. pylori was recovered by culture. In this case, 1st PCR was negative but 2nd PCR was positive. From a fecal sample of a patient infected with H. pylori, H. pylori was detected only by combination of IMB separation and PCR, although H. pylori was not recovered by culture. These results indicate that IMB separation technique followed by cultivation or PCR would be useful for estimation of the presence of H. pylori fecal samples.

Enzyme-Linked Immunosorbent Assay↗
PubMed2003

Clostridium difficile and enterotoxigenic Bacteroides fragilis strains isolated from patients with antibiotic associated diarrhoea.

From the fecal samples of 332 patients with a clinical diagnosis of antibiotic associated diarrhoea (AAD), 131 Clostridium difficile strains were isolated. For detection of toxin A in the isolated strains the enzymatic immunoassay was used. The cytopathic effect was determined on McCoy cell line. PCR was used for the detection of non-repeating and repeating sequences of toxin A gene and non-repeating sequences of toxin B gene. One hundred and six isolated C. difficile strains were TcdA(+)TcdB(+), 10 strains TcdA(-)TcB(+) and 15 were non-toxigenic TcdA(-)TcdB(-). Out of the same fecal samples 50 Bacteroides fragilis strains were isolated. All B. fragilis strains were tested in PCR reaction for fragilysine gene detection (bft). In 9 strains (18%) this gene was detected and the strains could be assumed as enterotoxigenic Bacteroides fragilis (ETBF). In 4 fecal samples toxigenic C. difficile (TcdA(+)TcdB(+)) was found simultaneously with ETBF. One sample contained C. difficile (TcdA(-)TcdB(+)) and ETBF. Out of 4 fecal samples only ETBF was isolated. The cytotoxicity of ETBF strains was tested on HT29/C1 human colon carcinoma cell line. The cytotoxicity titer in the range of 20 and 80 was observed.

Journal Article↗
PubMed2001

Response of river otters to experimental exposure of weathered crude oil: fecal porphyrin profiles.

Profiles of porphyrins were characterized in fecal samples from river otters (Lontra canadensis) experimentally exposed to weathered crude oil to determine effects on heme synthesis. Fifteen male river otters were randomly assigned to three groups of five individuals each representing a control group, a low-dosage group that received 5 mg/kg body mass of oil per day, and a high-dosage group that received 50 mg/kg body mass of oil per day. Mean levels of coproporphyrin III (CoproIII) and protoporphyrin IX (ProtoIX) in fecal samples collected from all experimental river otters were higher throughout the experimental period than levels of CoproIII and ProtoIX in fecal samples collected previously at two field sites. No statistically significant differences in levels of CoproIII and ProtoIX were observed between treatment groups, although a trend of reduction in variability in CoproIII was observed in the low- and high-dose groups. We found no relation between levels of CoproIII and ProtoIX, suggesting that the process of disruption that leads to oxidation of the precursors of porphyrins is probably nonlinear. Our results also indicate that the interaction between oiled induced reduction in hemoglobin levels and induction of CYP1A1 corresponded with significantly lower levels of ProtoIX in the fecal samples, possibly representing high demand for ProtoIX. Therefore, while this experiment does not support the use of porphyrin profiles as an individual biomarker, it does suggest that the latter may be valuable when a weight of evidence is used in an ecotoxicological risk assessment in which the interactions between several biomarkers are explored.

Animals↗