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At least 739 records · Page 41Linked to original sources
PubMed2005

A case of Munchausen syndrome by proxy with subsequent suicide of the mother.

Munchausen syndrome by proxy is a subtle and difficult to diagnose form of child abuse in which the carer (usually the mother) simulates, manipulates or produces symptoms of illness in the victim. In most cases the detrimental effect is caused by applying foreign substances or by airway obstruction. In the presented case a 20-month-old girl developed a spreading soft-tissue infection resistant to treatment on the left upper arm after vaccination, which required a number of surgical interventions. Repeatedly, microorganisms from the intestinal flora were isolated from the wound secretion. After the girl suffered respiratory and circulatory arrest, which required resuscitation measures, chemical toxicological tests revealed not medically prescribed benzodiazepines in serum and urine. When the mother, a trained nurse, was confronted with the allegation to have manipulated the symptoms of the illness she committed suicide. The forensic autopsy of the suicide produced numerous hints suggesting chronic self-damaging behaviour described as Munchausen syndrome. This case shows a number of manipulation forms with the maintenance of a chronic skin and soft tissue infection belonging to the rarer forms of inflicting damage to the child. It also illustrates that confrontation with the allegation of Munchausen syndrome by proxy creates a very stressful emotional situation that may lead to a suicidal act.

Chronic Disease↗
PubMed1997

Molecular and biochemical characterization of phosphoglucomutases from Entamoeba histolytica and Entamoeba dispar.

Entamoeba histolytica and Entamoeba dispar have only recently been defined as two separate species. E. histolytica, the pathogenic species, is the microorganism causing invasive intestinal amoebiasis and/or liver abscess, while the morphologically similar E. dispar is nonpathogenic and noninvasive. The gold standard for the distinction of the two species has been the isoenzyme electrophoresis of phosphoglucomutases (EC 5.4.2.2) and hexokinases (EC 2.7.1.1), but there had also been a controversy about the possibility of a conversion of isoenzyme patterns. In this study, we cloned the phosphoglucomutase (PGM) cDNAs from the pathogenic and the nonpathogenic species. The deduced amino acid sequences were only 2.4% different. The cDNAs were expressed in Escherichia coli under the control of a T7 RNA polymerase promoter. The recombinant polypeptides displayed strong phosphoglucomutase activity, each of the recombinant enzymes comigrated with its natural counterpart from E. histolytica and E. dispar in the starch gel electrophoresis. Our results give a biochemical interpretation of the PGM isoenzyme pattern and support the clear distinction between the two species.

Amino Acid Sequence↗
PubMed2003

Retention of virulence in viable but non-culturable halophilic Vibrio spp.

The viable but non-culturable (VBNC) forms of two environmental strains of Vibrio alginolyticus 1 and Vibrio parahaemolyticus 66 and one strain of V. parahaemolyticus ATCC 43996 showing virulence characteristics (hemolysin production, adhesive and/or cytotoxic ability, in vivo enteropathogenicity) were obtained by culturing bacteria in a microcosm consisting of artificial sea water (ASW) and incubating at 5 degrees C with shaking. Every 2 days, culturability of the cells in the microcosm was monitored by spread plates on BHI agar and total count and the percentage of viable cells were determined by double staining with DAPI and CTC. When cell growth was not detectable (<0.1 CFU/ml), the population was considered non-culturable and, then, the VBNC forms were resuscitated in a murine model. For each strain, eight male Balb/C mice were intragastrically inoculated with 0.1 ml of concentrated ASW bacterial culture. Two mice from each group were sacrificed at 2, 4, 8, and 12 days after challenge for autopsy and re-isolation of the microorganisms from the intestinal tissue cultures. Isolation was obtained in 25% of the animals challenged with the VBNC V. alginolyticus strain, in 37.5% of those challenged with the VBNC V. parahaemolyticus strain of environmental origin and in 50% of the animals infected with VBNC V. parahaemolyticus ATCC 43996. The strains thus isolated were again subjected to biological assays to determine the retention of pathogenicity. The virulence characteristics that seemed to disappear after resuscitation in the mouse were subsequently reactivated by means of two consecutive passages of the strains in the rat ileal loop model. The results obtained indicate that VBNC forms of the strains examined can be resuscitated and retain their virulence properties.

Animals↗
PubMed2006

Goat milk oligosaccharides are anti-inflammatory in rats with hapten-induced colitis.

Oligosaccharides are included among the anti-inflammatory components of milk because of their prebiotic properties and their capacity to act as receptors of microorganisms. Here the intestinal anti-inflammatory effect of goat milk oligosaccharides (O) was assessed in trinitrobenzenesulfonic (T) acid-induced colitis in rats. Rats were randomly assigned to three different groups. Two groups (T and OS) of colitic rats and a control group (C) were studied. Group OS received 500 mg/(kg.d) of goat milk oligosaccharides orally, starting 2 d before the colitis induction until d 6, and groups T and C received the vehicle. When compared with the T group, the OS group showed decreased anorexia and body weight loss; reduced bowel wall thickening and longitudinal extension of necrotic lesions; downregulated colonic expression of interleukin 1beta, inducible nitric oxide synthase, cyclooxygenase 2, and mucin 3; and increased trefoil factor 3. Thus, goat milk oligosaccharides have anti-inflammatory effects in rats with experimental colitis and may be useful in the management of inflammatory bowel disease.

Animals↗
PubMed1999

The normal faecal microflora does not affect the adhesion of probiotic bacteria in vitro.

Adhesion of probiotic microorganisms to the intestinal mucosa is considered important for many of the reported health effects. The influence of the endogenous microflora on the adhesion of four probiotic lactobacilli to immobilised intestinal mucus was investigated. It was observed that pre-treatment of the immobilised mucus with faecal extract slightly increased the adhesion of Lactobacillus GG. Pre-treatment of the immobilised mucus with faecal bacteria did not affect the adhesion of the tested strains. These results suggest that the normal microflora may not greatly affect the initial adhesion of the probiotic bacteria. This validates the results of earlier reports where the influence of the normal microflora was not taken into account.

Adult↗
PubMed2005

Effect of pH on an in vitro model of gastric microbiota in enteral nutrition patients.

Patients with dysphagia due to oropharyngeal disease or cerebrovascular accident require long-term nutritional support via enteral feeding, which often results in microbial overgrowth in the upper gastrointestinal (GI) tract. Gastric acid is the primary innate defense mechanism in the stomach and has been assumed to provide an effective barrier to microbial colonization at pH values of <4. To evaluate the efficacy of gastric acid as a barrier to overgrowth, the microbiota of gastric and duodenal aspirates was assessed by culturing methods. Additionally, a fermentor-based model incorporating enteral nutrition tubing of the gastric microbiota of enteral nutrition (EN) patients was constructed to assess the effect of pH on the microbiota. Results showed that gastric acidity had a relatively small effect on the numbers of microorganisms recovered from intestinal aspirates but did influence microbiota composition. Similarly, at pH 3 in the fermentor, a complex microbiota developed in the planktonic phase and in biofilms. The effect of pH on microbiota composition was similar in aspirates and in the fermentors. Candidas and lactobacilli were aciduric, while recoveries of Escherichia coli and Klebsiella pneumoniae decreased as pH was reduced, although both were still present in significant numbers at pH 3. Only Staphylococcus aureus and Bifidobacterium adolescentis persisted at higher pH values both in vitro and in vivo. Lactate and acetate were the main organic acids detected in both aspirates and fermentors. These data show that the simulator used in this investigation was capable of modeling the effects of environmental influences on the upper GI microbiota of EN patients and that gastric pH of <4 is not sufficient to prevent microbial overgrowth in these individuals.

Bacteria↗
PubMed2000

Vancomycin-resistant enterococci.

After they were first identified in the mid-1980s, vancomycin-resistant enterococci (VRE) spread rapidly and became a major problem in many institutions both in Europe and the United States. Since VRE have intrinsic resistance to most of the commonly used antibiotics and the ability to acquire resistance to most of the current available antibiotics, either by mutation or by receipt of foreign genetic material, they have a selective advantage over other microorganisms in the intestinal flora and pose a major therapeutic challenge. The possibility of transfer of vancomycin resistance genes to other gram-positive organisms raises significant concerns about the emergence of vancomycin-resistant Staphylococcus aureus. We review VRE, including their history, mechanisms of resistance, epidemiology, control measures, and treatment.

Anti-Bacterial Agents↗
PubMed1975

Bis-(p-hydroxyphenyl)-pyridyl-2-methane: The common laxative principle of Bisacodyl and sodium picosulfate.

After both oral and rectal administration in humans (4,4'-diacetoxy-diphenyl)-(pyridyl-2)-methane (bisacodyl, Dulcolax) and 4,4'-(2-pyridyl-methylene)-diphenol-disulfuric acid semiester disodium (sodium picosulfate, Laxoberal) are hydrolyzed to bis-(p-hydroxyphenyl)-pyridyl-2-methane (BHPM). In both cases BHPM is responsible for the laxative action. Experiments in rats and guinea pigs have shown that the hydrolysis of picosulfate, in contrast to that of bisacodyl, is attributable to the microorganisms of the intestinal flora.

Administration, Oral↗
PubMed2005

[Medical microbial ecology: some of the overall results and research prospects].

The review discusses data of fundamental and applied research in human microbial ecology. Having analyzed these data, the author concludes that in the natural habitats these is practically no biochemical process or function of a living organism that would not need a direct or indirect participation of symbiotic organisms. The condition of these organisms should be considered one of the main biogenic factors that determine human health and pathology. The author offers a range of measures that would allow development and introduction of fundamentally new approaches to prevention and treatment of the most wide-spread diseases, as well as application of microorganisms of normal intestinal microflora of man in industrial biotechnology.

Bacteria↗
PubMedDate not supplied

[Blastocystis hominis in Canavese: a retrospective study of samples received for fecal parasitological examination at the Ivrea- Castellamonte Hospital over 42 months].

In the last ten years the interest in the controversial Blastocystis hominis microorganism of the intestine has greatly increased. The authors conducted a retrospective study of feces for parasitology investigations at the Ivrea-Castellamonte hospital. These investigations lasted 42 months (1/1/1988-31/6/1991) and the authors focused their attention on samples with 5 or more Blastocystis hominis at the microscopically examination with a 40X phase objective. During the study 2,138 samples of feces (belonging to 1552 patients) arrived. 284 samples (13.3%), corresponding to 200 patients (12.9%), proved to be positive for one or more parasites. In 155 samples (7.2%) regarding 109 patients (7.0%)--53 males, 56 females--Blastocystis was present. These patients were between 2 and 78 years of age. In 19 (17.4%) of these patients other parasites were associated, parasites such as Giardia lamblia (in 6 cases), Entamoeba coli (in 4 cases), Entamoeba spp. (in 2 cases), Entamoeba histolytica (in one case), Entamoeba hartmanni (in one case), Iodamoeba butschlii (in one case), Hymenolepis nana (in one case); helminths (in 3 cases). The most effect proved to be those patients between 21 and 50 years of age (53 of 98 patients). Few infants were affected. The greatest incidence of Blastocystis hominis infection occurred during the months of January to June. The authors conclude by considering how the incidence data of such parasitosis in the Canavese region can be superimposed on as much as has been observed in territories which are very different regarding social-economic and geoclimatic conditions. The authors think it is necessary to start a prospective clinical-epidemiological investigation in the Canavese region with a view to defining the clinical approach to the parasite under discussion in a better way.

Adolescent↗
PubMed1991

Bacterial translocation.

The phenomenon of bacterial translocation, the movement of viable indigenous microorganisms across the intestinal epithelial barrier, has been recognized for almost 100 years. At the present time, the precise mechanism of microbial transport is unknown. Active epithelial uptake and phagocyte-mediated transport have been proposed as likely explanations for the extraintestinal movement of bacteria to mesenteric lymph nodes and distant organ sites. Translocation has been proposed as the pivotal process associated with intestinal origin portal sepsis in seriously ill and immunocompromised patients. While several etiologic factors can be implicated in the pathogenesis of bacterial translocation, the present clinical implications are based almost solely on studies of dogs, rats and mice. Present investigations continue to suggest a causal relationship between intestinal mucosal integrity and infection by indigenous gastrointestinal bacteria.

Animals↗
PubMed1988

[Identification of 5-aminovaleric acid as a characteristic product of metabolism of various Clostridium species].

An unusual ninhydrin-positive compound has been isolated from feces of accidentally contaminated Sprague-Dawley autbred rats and identified by mass spectrometry and 1H-NMR spectroscopy techniques as 5-aminovaleric acid. The described procedure of isolation, purification and structure determination can be recommended as a general method of identification of unusual ninhydrin-positive compounds in complex mixtures of biological origin. The 5-aminovaleric acid was found to be produced by an anaerobic bacterium Clostridium bifermentans. It is shown that not all Clostridium spp. excrete his amino acid and that the majority of microorganisms, normally inhabiting intestine of rats, simians and man, do not possess this ability. On the basis of data obtained, the test for 5-aminovaleric acid is proposed to be included into the taxonomy of bacteria.

Amino Acids↗
PubMed1997

[Recurrent urinary tract infections. Biological suppositions and clinical treatment with thymopentin].

BACKGROUND: Urinary tract infections (UTI) are a common usual pathological event. They relapse often due to the periurethral colonization of microorganisms from the intestinal bacterial flora. They also constitute an important and considerable social and clinical problem. The absence of inducing organic conditions or an infective focus at the base of the pathogenetic mechanism suggests the existence of alterations of the immune response of the subject. MATERIALS AND METHODS: In this work we wanted to verify if, in those subjects with relapsing UTI (more than four events every year) cure with "biological" response modifiers, particularly "thymopentin", meaningfully reduced the number of events. RESULTS: The results obtained confirm that for those cases in which the chemo-antibiotic therapy did not have the expected results, it is rational to support it with an immune-modulating drug (thymopentin). In fact the post-therapy reduction of UTI observed during two years of follow-up is statistically significant when compared to the average of UTI before therapy. CONCLUSIONS: The "cost-benefits" analysis should prove to be a saving in favour of the use of thymopentin, taking into consideration the reduction of chemo-antibiotics consumption and the lower number of working hours lost every year.

Adjuvants, Immunologic↗
PubMed1998

Current concept of the role of monocytes/macrophages in inflammatory bowel disease--balance of proinflammatory and immunosuppressive mediators.

Macrophages are important in providing the first line of intestinal defence against microorganisms or toxins that break the epithelial barrier, by presenting antigen to sensitised T cells and releasing a variety of cytokines and inflammatory mediators. During active states in inflammatory bowel disease, large numbers of monocytes leave the bloodstream and migrate into the inflamed mucosa and submucosa. Phenotypic studies have previously shown the presence of much more marked macrophage heterogeneity in inflammatory bowel disease mucosa than in normal mucosa. In both Crohn's disease and in ulcerative colitis, distinct macrophage populations have been found, being prominent in active disease, but absent from normal mucosa. Studies in our institution have shown that the Ca(2+)-binding proteins MRP8 and MRP14 as well as their heterocomplex MRP8/14 (27E10 epitope) are expressed in the majority of granulocytes and macrophages in active but not inactive inflammatory bowel disease. Furthermore, a strong complex MRP8/14 immunoreactivity was present in epithelial cells of the terminal ileum adjacent to ulcerative and fissuring lesions, while epithelial cells of large bowel tissues were consistently negative. In vitro studies revealed that interleukin-13, interleukin-10 and interleukin-4 strongly suppress secretion of different monocytic proteins. A combination of TH2-cytokines even at suboptimal concentrations significantly suppressed protein secretion, much more than using interleukin-13, interleukin-10 or interleukin-4 at a double concentration alone. Our morphological findings demonstrate the presence of MRP8/14 (27E10 antigen) both in monocytes/macrophages and in epithelial cells in active inflammatory bowel disease. Systemic or topical application of combined cytokine treatment might be a new effective therapeutic approach for chronic inflammatory bowel disease especially in those cases in which monocytes/macrophages lose their ability to respond, to some degree, to anti-inflammatory cytokines.

Animals↗
PubMedDate not supplied

[Experimental investigations on the effect of Escherichia coli and Clostridium perfringens on the steroid 4-pregnen-20beta-ol-3-one].

In the context of investigations about the stability of sexual steroids, which are excreted from animals to the environment, it was checked whether microorganisms of the intestinal microflora influence the degradation of these compounds. The germs used were Escherichia coli or Clostridium perfringens. The hormone investigated was the 4-pregnene-20 beta-ol-3-one (20 beta P4). 20 beta P4 was incubated together with the microbes (experimental groups) and without these (control groups) in nutrient medium for the bacteria over 48 hours at 37 degrees C or 42 degrees C. As a result no differences in concentration were found between the experimental and control groups after incubation. Neither an effect of Escherichia coli nor one of Clostridium perfringens was detectable on the concentration of 20 beta P4. However there was a significant decrease of the 20 beta P4-concentration after the incubation over 48 hours at 37 degrees C or 42 degrees C in both the experimental and control groups. That could indicate a thermal degradation of the compound tested.

Clostridium perfringens↗
PubMed2001

[Enteral insufficiency syndrome in acute ileus and ways for its correction].

Based on experimental investigations in 26 mongrel dogs, we established that due to acute ileus (AI) proximal and distal regions of small intestine are colonized by pathogenic aerobic and anaerobic microorganisms, which causes occurrence of enteral insufficiency syndrome (EIS). Absorption of microorganisms and their toxins through intestinal wall leads to bacteriemia, endotoxemia and morphological insufficiency of parenchymatous organs. The results of treatment of 486 patients with AI of different etiology are studied. Based on clinical and diagnostical changes 4 stages of EIS are separated. The rate of post-operative complications depends on severity of EIS. When treating the patients with AI the severity of EIS should be taken into consideration. Specific pre-operative preparation, the relevant technology of surgical intervention and post-operative treatment should be used differently at every stage of the disease.

Acute Disease↗
PubMed1997

Human colonic microbiota: ecology, physiology and metabolic potential of intestinal bacteria.

In both health and disease, the colonic microbiota plays an important role in several areas of human physiology. This complex assemblage of microorganisms endows great metabolic potential on the large intestine, primarily through its degradative abilities. Many hundreds of different types of bacteria, varying widely in physiology and biochemistry, exist in a multitude of different microhabitats in the lumen of the large gut, the mucin layer and on mucosal surfaces. Both microbiota and host obtain clear benefits from association. For example, growth substrates from diet and body tissues, together with a relatively stable environment for bacteria to proliferate are provided by the host, which in turn has evolved to use butyrate, a bacterial fermentation product, as its principal source of energy for epithelial cells in the distal bowel. The main sources of carbon and energy for intestinal bacteria are complex carbohydrates (starches, non-starch polysaccharides). Carbohydrate metabolism is of great importance in the large intestine, since generically, and in terms of absolute numbers, the vast majority of culturable microorganisms are saccharolytic. The amounts and types of fermentation products formed by colonic bacteria depend on the relative amounts of each substrate available, their chemical structures and compositions, as well as the fermentation strategies (biochemical characteristics and catabolite regulatory mechanisms) of bacteria participating in depolymerization and fermentation of the substrates. Protein breakdown and dissimilatory amino acid metabolism result in the formation of a number of putatively toxic metabolites, including phenols, indoles and amines. Production of these substances is inhibited or repressed in many intestinal microorganisms by a fermentable source of carbohydrate. Owing to the anatomy and physiology of the colon, putrefactive processes become quantitatively more important in the distal bowel, where carbohydrate is more limiting.

Adult↗