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At least 973 records · Page 54Linked to original sources
PubMed1984

The effect of selective decontamination of the digestive tract on colonisation and infection rate in multiple trauma patients.

122 multiple trauma patients staying in the ICU for 5 or more days and needing mechanical ventilation were investigated to determine the effect of selective decontamination of the digestive tract on prevention of infection. The (retrospectively studied) control group of 59 patients received no antibiotic prophylaxis. The infection rate during ICU-stay was 81%. Most infections were caused by potentially pathogenic microorganisms (PPM) from the oral cavity or the intestines (i.e. endogenous infections). The oropharynx and the intestines were rapidly colonised with ICU-associated gram-negative bacilli. After 2 weeks more than 80% of patients were found colonised. This secondary colonisation of the digestive tract is a very important stage in the pathogenesis of infections. Sixty-three patients were selectively decontaminated with nonabsorbable antibiotics, administered through the gastric tube even if peristalsis was absent. Emphasis was laid on the selective decontamination of the oral cavity, using topical application of an antibiotic paste. With this technique the oral cavity was free of PPM within 3 days in most patients. No secondary colonisation was found. Rectal colonisation decreased significantly after 5 days. Secondary colonisation occurred in 9 patients with PPM sensitive to the antibiotics used. The prophylactic regimen included systemic cefotaxim, directed against early endogenous infection. The suppression and after some time the absence of the endogenous source of PPM resulted in a significant reduction of colonisation and infection. The total infection rate decreased to 16%.

Administration, Topical↗
PubMed1990

Prophylaxis of necrotizing enterocolitis by oral IgA-IgG: review of a clinical study in low birth weight infants and discussion of the pathogenic role of infection.

Necrotizing enterocolitis, a severe gastrointestinal disease in the neonatal period, affects primarily premature infants. Perinatal complications that predispose the neonate to systemic hypoxia are frequent in infants with necrotizing enterocolitis. Ischemia of the intestinal mucosa may facilitate the invasion of enteric microorganisms in stressed low birth weight infants. Geographical and temporal clustering of outbreaks of the disease and the termination of epidemics by standard infection control underline the importance of infectious agents in the development of this disease. Several studies have established the immunoprotective effect of orally administered antibodies against infection of the gastrointestinal mucosa in children and adults. Anecdotal evidence suggested that feeding of human immune globulin might have a positive effect on the incidence of necrotizing enterocolitis in premature infants. This paper reviews a prospective, randomized, controlled trial of the efficacy of an oral immune globulin preparation (published in detail in the New England Journal of Medicine, Vol. 319, pp 1-7, 1988) and discusses the pathogenic role of infection in necrotizing enterocolitis.

Administration, Oral↗
PubMed1989

Inhibition of phosphatase by open-chain nucleoside analogues in insects.

(S)-9-(2,3-dihydroxypropyl) adenine (DHPA), D-eritadenine and some other open-chain nucleoside analogues, which exhibit adverse biological effects in microorganisms, plants and animals, cause pronounced inhibition of intestinal phosphatases in the hemipteran insect Pyrrhocoris apterus. The rate of p-nitrophenylphosphate hydrolysis by homogenates from intestinal epithelium and Malpighian tubules was inhibited up to 94% by 2-10 millimolar concentrations of these drugs. This effect is stronger than that of sodium fluoride, which is recognized as a common inhibitor of phosphatase. We conclude that inhibition of phosphatase activity in the digestive and excretory organs may be responsible for the previously reported massive excretion of phosphorylated derivatives of the nucleoside analogues after their oral administration to insects.

Acid Phosphatase↗
PubMed2006

Phenolics and antimicrobial activity of traditional stoned table olives 'alcaparra'.

In the present work, we report the determination of phenolic compounds in 'alcaparra' table olives by reversed-phase HPLC/DAD, and the evaluation of their extract in vitro activity against several microorganisms that may be causal agents of human intestinal and respiratory tract infections, namely Gram positive (Bacillus cereus, Bacillus subtilis, and Staphylococcus aureus), Gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae) and fungi (Candida albicans and Cryptococcus neoformans). Three flavonoidic compounds were identified and quantified: luteolin 7-O-glucoside, apigenin 7-O-glucoside, and luteolin. At low concentrations (0.05mg/mL) 'alcaparra' extract revealed significant inhibition of both Gram positive and Gram negative bacteria growth, with exception of P. aeruginosa. Nevertheless, no antifungal activity was observed at the tested concentrations.

Anti-Bacterial Agents↗
PubMed1997

Molecular cloning and characterization of the chromosomal gene for human lactoperoxidase.

Lactoperoxidase (LPO) is an oxidoreductase secreted into milk, and plays an important role in protecting the lactating mammary gland and the intestinal tract of the newborn infants against pathogenic microorganisms. In this study, the human LPO chromosomal gene was molecularly cloned, and its gene organization was determined. The human LPO gene was found to be arranged with the myeloperoxidase (MPO) gene in a tail-to-tail manner. Similar to the human MPO and eosinophil peroxidase (EPO) genes, the human LPO gene is split by 11 introns and spans 28 kb. Unlike most introns in mammalian gene, the 5' splice donor sequence of intron 11 starts with GC instead of GT. When the minigene comprised of exon 11, intron 11 and exon 12 of the human LPO gene was introduced into COS cells, the correct splicing of the intron was found, suggesting the intron 11 of the human LPO gene is functional. The coding sequence of human LPO consists of 2136 bp, and codes for a protein of 712 amino acids. The amino acid sequence of human LPO has 51% similarity with those of both human MPO and EPO, suggesting that these peroxidase genes have evolved from a common ancestral gene. On the other hand, the nucleotide sequences of the 5' promoter regions of these peroxidase genes exhibit no similarity among them, which agrees with their tissue-specific expression.

Amino Acid Sequence↗
PubMed1998

Kinetics of particle uptake in the domes of Peyer's patches.

Uptake of particulate antigenic matter, including microorganisms and vaccine-bearing microspheres, by the intestinal mucosa takes place in the domes of the gut-associated lymphoid tissues and is achieved by membranous (M) cells, which continuously transport particles from the lumen to the underlying tissue where some particle components initiate immune reactions. Using yeast as tracer, we investigated the kinetics of particle uptake in the Peyer's patches of pigs. A suspension of baker's yeast (Saccharomyces cerevisiae) was injected into the gut lumen of anesthetized minipigs; the position of yeast cells in the tissue was determined after 1, 2.5, 4, and 24 h using fluorescence light- and thin-section electron microscopy. After 1 h, 18.5% of all M cells had taken up or were in close contact with yeast cells. The intercellular space of the epithelium contained a maximum of 60.8% of all yeast cells found in the tissue after 2.5 h, but only 1.3% had been phagocytosed by macrophages. After 4 h most yeast cells (77.8%) were found beneath the basal lamina, and most of these (89%) were found in macrophages. No yeast cells were detected in the Peyer's patch domes 24 h after application. The data show that transcytosis of yeast particles (3.4 +/- 0.8 micron in diameter) by M cells takes <1 h. Without significant phagocytosis by intraepithelial macrophages, the particles migrate down to and across the basal lamina within 2.5-4 h, where they quickly get phagocytosed and transported out of the Peyer's patch domes.

Animals↗
PubMed1995

Metabolism of peptide drugs by the microorganisms in rat cecal contents.

The metabolism of insulin and calcitonin by microorganisms was examined in rat cecal contents. Both insulin and calcitonin were markedly degraded. Calcitonin was more susceptible to proteolysis in rat cecal contents than insulin. Calcitonin was also rapidly degraded in supernatant, while we found few degradation products of insulin. These findings suggest that care should be taken to metabolize the peptide drugs by microorganisms when they are administered to the large intestine for colon-specific drug delivery.

Animals↗
PubMedDate not supplied

[AF, a new bacterial preparation based on lactobacilli and its biological properties].

A highly efficient bacterial composition "AF" which includes representatives of two genera of microorganisms Enterococcus faecium and Lactobacillus acidophilus has been created as a result of analysis of biological properties of a number of strains of lactic-acid bacteria. Their biological properties--antagonistic activity in respect to pathogenic and conditionally pathogenic microorganisms, ability to adhesion and function in the intestine, sensitivity to antibiotics, etc., have been studied in the laboratory conditions. Prospects of the use of the given composition in production of milk products of functional effects have been shown.

Animals↗
PubMed2000

Sulfite-reducing clostridia in the sediment of a high mountain lake (Laguna Grande, Gredos, Spain) as indicators of fecal pollution.

We studied the vertical distribution of sulfite-reducing clostridia in the sediment of a Spanish high-mountain lagoon (Laguna Grande de Gredos, central Spain), with optimal sediment characteristics (temperature < 20 degrees C) to maintain spores without growing. This allowed us to assess the original numbers of sulfite-reducing clostridia endospores settled, without postdepositional growing. Sulfite-reducing clostridia are normal inhabitants of the intestinal microbiota of humans and other mammals. These microorganisms may form endospores, which allow the bacteria to survive in almost any habitat, either terrestrial or aquatic, waiting for favorable conditions for growth. Sulfite-reducing clostridia could be suitable indicators of past human pollution because they have a great longevity in natural habitats and they cannot multiply at temperatures below 20 degrees C or in the presence of O2. We found a great increase in the numbers of clostridia (expressed as colony-forming units per gram [CFU/g] of dry weight of sediment) since the 1970s, which reflects the rise of human pressure caused by the practice of outdoor activities. Clostridia CFU/g rose dramatically after the faulty operation of the depuration system of a mountain refuge built close to the lagoon. We compared the vertical distribution of clostridia CFU/g from Laguna Grande sediments with those from a neighbor lagoon (Laguna Cimera), which showed less tourist pressure and no direct disposal of sewage. Finally, we agree with the usefulness of the numbers of sulfite-reducing clostridia as indicators of past pollution.

Clostridium↗
PubMed2001

[Microecological system and its importance in evaluation of the effectiveness of biologically active supplements and probiotic products].

A possibility to estimate a quality of bioactive supplements and probiotical foods by their influence on microecological system of a gastrointestinal tract are exhibited as a result of multiyear research. The consist and biological activity of micropopulations, including the normalization of level of protective intestinal microflora, the increasing their antibiosis activity, the elimination of potentially pathogenic microorganisms, the excretion of volatile phenols and indican with urine, the content of volatile fatty acids, enzymes, secretory immunoglobulins in feces, destruction in vitro cholic acid and cholesterol etc., are tested as indicators. The reasoned supposal is advanced that the wide spread of disbacteriosis is connected not only with changing of defence mechanisms (reactions) of macroorganism, but also with accumulation of pathogenic features in microorganisms by action of environmental factors.

Bacteria↗
PubMed1990

[Contaminated small bowel syndrome in infants caused by gram-negative bacteria and yeasts].

The upper small intestine is usually "sterile" in a healthy individuals, but due to some reasons the number of microorganisms may reach or increase above 10(4)/ml, leading to the contamination of the small intestine, which may cause severe malabsorption. The authors have diagnosed this syndrome in 50 children, aged between 1 month and 3 years, using breath hydrogen test and duodenal juice culture. Most of these children had growth retardation. According to their experience the authors found that the oral antibiotic is the effective treatment of this syndrome.

Anti-Bacterial Agents↗
PubMed1989

[Infectious diarrhea in the adult].

Infectious diarrhoeas are usually divided into two types; toxinogenic and invasive. Invasive diarrhoeas are copious and responsible for dehydration which is the principal clinical sign; mucosal lesions and bacteraemia are absent. The most typical of toxinogenic diarrhoeas is cholera, but enterotoxicogenic E. coli and Aeromonas infections have similar clinical features. In invasive diarrhoeas the responsible microorganisms penetrate into the epithelial cells of the intestine, producing fever and stools that contain blood and mucus. However, some organisms causing invasive diarrhoeas secrete cytotoxins; they include Shigella spp., Salmonella spp, some strains of E. coli, Campylobacter jejuni and Yersinia spp. When diarrhoea occurs in patients under antibiotics pseudomembranous colitis due to the proliferation of Clostridium difficile must be suspected; the diagnosis is suggested by endoscopy and confirmed by bacteriology. Toxic and infectious diarrhoeas due to food are increasingly frequent; they are usually caused by Salmonella spp., but sometimes by Clostridium perfringens or Staphylococcus aureus. In patients with suspected infectious diarrhoea symptomatic treatment combined or not with intestinal antibacterial agents is immediately initiated in most cases; stool cultures are reserved to severe or protracted diarrhoeas. Specimens must be collected under the best conditions and rapidly sent to the laboratory.

Adult↗
PubMedDate not supplied

[Urinary tract infections: bacteriological aspects of recurrent cystitis].

Gram-negative bacteria, and above all E. coli and Proteus sp., cause the great part of UTI. Some characters of microorganisms (as the capsular K antigen, the production of haemolysin and the endotoxin of cell wall) can affect the invasive capacity and the virulence of E. coli. The bacterial adherence, due to the presence of fimbriae, seems to be correlated to the persistence of microorganisms in lower urinary tract. Moreover Enterobius vermicularis, intestinal parasite frequent in infancy, can transport in girls E. coli strains from the rect, through the urethra, to the bladder. The data regarding the importance of the immune local response are not clear yet.

Cystitis↗
PubMed1984

Trends in the development of beta-lactam antibiotics.

In many ways it is ironic that the first description of a beta-lactamase occurred in 1940 with an enzyme isolated from Escherichia coli since in recent years there has been a major interest in Gram-negative species and the development of agents to overcome the hydrolytic action of beta-lactamases of Gram-negative species. There have been four distinctly different approaches to the development of new beta-lactam antibiotics. These have been the search for inhibitors of beta-lactamases and agents such as clavulanic acid and sulbactam are examples of compounds which by virtue of Kcat function act as suicide inhibitors and make old antibiotics new. There has been the modification of the penicillin and cephem nucleus to increase beta-lactamase stability or failing that to improve the ability of the compounds to pass through the cell wall and increase affinity for critical beta-lactam receptors, i.e. penicillin-binding proteins. There has been the development of carbapenem type of agents such as imipenem which would have broad activity including aerobic, anaerobic, Gram-positive and Gram-negative species. There has been the discovery of the monobactam agents of which aztreonam is an example of a compound with great beta-lactamase stability but with activity limited to Gram-negative aerobic species. Bacterial resistance has indeed been the major factor that has modified use of beta-lactams and influenced the development of the aforementioned types of drugs. The widespread presence of beta-lactamases in common pathogens such as Haemophilus influenzae, Neisseria gonorrhoeae, Escherichia coli, Klebsiella sp., Pseudomonas aeruginosa, and Bacteroides fragilis has made it necessary to have beta-lactamase stable compounds for initial therapy of infection. It is possible to analyze structure-activity relations of beta-lactam compounds to determine changes which will be most advantageous in light of known and expected resistance patterns. But the increased realization in recent years of the importance of the pharmacokinetics of beta-lactam drugs has made it essential that the development of new compounds be based on an integration of microbiological and pharmacokinetic parameters. Interest in the prevention of resistant flora has also affected the development of new drugs since it is increasingly appreciated that alteration of intestinal flora contributes to selection of drug resistant microorganisms. Finally, new toxicities or adverse effects associated with the use of certain new agents has modified the development of certain compounds.

Anti-Bacterial Agents↗
PubMed1985

Possible association of mucous blanket integrity with postirradiation colonization resistance.

Radiation-induced infections can be associated with changes in colonization potential of the intestine. Since the mucous blanket, which overlays the epithelium, is a major mucosal structure and is heavily colonized by microorganisms, we examined the status of the mucus after radiation and evaluated susceptibility to intestinal challenge with bacteria. A downward shift (2.5 X 10(8) cells/g to 5.3 X 10(5)) of total facultatively anaerobic bacteria of the ileum of C3HeB/FeJ mice was detected by 3 days post exposure to 10 Gy 60Co. Numbers of flora returned to normal by 11 days after radiation. Scanning electron microscopy was used to show that the loss of bacteria could be associated with major disruptions of the continuity of the mucous blanket. The pathogen Pseudomonas aeruginosa adhered to mouse mucous films used in in vitro assays. When irradiated mice were challenged orally with 1 X 10(5) P. aeruginosa on days 1, 2, or 3 after irradiation, a progressive increase in susceptibility was seen, but no animals died before Day 4 postirradiation. Sensitivity to subcutaneous (sc) challenge with Pseudomonas also increased by Day 3 and was probably due largely to the profound neutropenia observed. Immunoglobulin G (Gamimmune), which protected burned mice infected with Pseudomonas, was ineffectual in treatment of 7 or 10 Gy irradiated mice challenged either orally or sc with the organism. The ileal mucosal barrier was compromised after radiation in ways which could facilitate epithelial colonization, an event which combined with other immunological and physiological decrements in this model can compromise the effectiveness of therapeutic modalities.

Animals↗
PubMed2006

First isolation of Dysgonomonas mossii from intestinal juice of a patient with pancreatic cancer.

BACKGROUND: Dysgonomonas species were first designated in 2000. However, clinical infections due to this microorganism have rarely been described. Our aim was to present the first isolation of Dysgonomonas mossii from intestinal juice of a patient with pancreatic cancer. METHODS: Predominantly appearing grayish-white colonies grown on chocolate and sheep blood agar plates were characterized morphologically by Gram stain, biochemically by automated instrument using Vitek II ID-GNB card together with commercially available kit systems, ID-Test HN-20 and API rapid ID 32A32A, and genetically by sequencing the 16S rRNA gene of the organism using a Taq DyeDeoxy Terminator Cycle Sequencing and a model 3100 DNA sequencer instrument. The isolate was further characterized by antimicrobial susceptibility using MicroFast 4J Panels and additional biochemical and physiological properties. RESULTS: The isolate was finally identified as D. mossii from the findings of the morphological, cultural, and biochemical properties together with the comparative sequence of the 16S rRNA genes. The isolate was highly susceptible to many antibiotics but resistant to penicillins and cephems. CONCLUSIONS: As D. mossii was rarely encountered in the clinical microbiology laboratory, it may be misidentified as an X-factor-dependent Haemophilus species due to its negative result for the porphyrin test. Accumulation of the case reports with the isolation of this species is expected to elucidate the infections due to D. mossii. The presence of D. mossii caused no significant clinical infection despite repeated isolations, as the patient had no conspicuous abdominal complaints. However, our report is a noteworthy and useful piece of information.

Bacterial Infections↗
PubMed1975

Studies of the infection of the cockroaches (Blattella germanica[L.]) with Bac. thuringensis.

The results of an experimental infection of the cockroaches Blattella germanica (L.) with some trade preparations containing Bac. thuringensis spores are presented. Biological studies supported by bacteriological and histological examinations of the excised intestines of the above insects have shown that the microorganisms studied are pathogenic for the cockroaches. This effect might be eventually applied as a biological method of eradication of the cockroaches in such environments, where chemical preparations can not be used or this disinfestation method would be complementary to the other method of disinfestation.

Animals↗
PubMed1996

[A case of hemorrhagic rectocolitis associated with the presence of intestinal spirochetes].

We report a case of a girl of 14 years old who developed a rapidly fatal chronic hemorrhagic rectocolitis. Several colonic biopsy specimens were studied by using the Vago stain. They showed many spirochetes attached end-to-end to the colonic epithelium. While the demonstration of a causal relationship between the intestinal symptoms and the presence of these spirochetes warrants further studies, the present observation outlines the need of researching this type of microorganisms through stains such as Vago stain whenever physicians are confronted with chronic intestinal inflammatory syndromes.

Adolescent↗