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[Effects of intra-operative colonic irrigation on colonic flora in patients with intestinal obstruction caused by left colonic carcinomas].

We studied the effects of intra-operative colonic irrigation on intestinal bacteria in patients with carcinomatous obstruction of the left colon. The results showed: The floral volume of aerobes and anaerobes in colonic content and mucosa in obstructive patients increased significantly (P < 0.01), but it was reduced obviously by intra-operative colonic irrigation (P < 0.01), reaching the level of that as in the nonobstructive patients who received oral antibiotics and mechanical intestinal preparation.

Colon↗

Segmental gut transit in diabetes mellitus: effect of cisapride.

Gut transit using radiopaque markers was assessed in 5 healthy subjects and 24 diabetic patients. In the diabetics, various parameters including duration of the disease and diabetic complications, such as neuropathy, retinopathy and nephropathy, were determined, and the relationships between gut transit times and these complications were evaluated. The effect of cisapride on gut transit was studied in 10 diabetic patients. Large intestinal, descending colon, distal colon, and whole gut transit times were delayed in diabetics with autonomic neuropathy compared to controls and to diabetics without autonomic neuropathy (P less than 0.01). There was no difference in proximal colon transit times among them. An inverse correlation was observed between CVRR and the transit times for descending colon, distal colon, large intestine and whole gut. Large intestinal and whole-gut transit times were delayed in diabetics with retinopathy or with nephropathy compared to diabetics without those complications (P less than 0.01). In the diabetics, oral administration of 7.5 mg/day of cisapride for 2 weeks significantly accelerated descending colon transit (P less than 0.05) and partially accelerated distal colon, large intestinal and whole-gut transit. It is concluded that diabetics with autonomic neuropathy have delayed transits for the whole gut and that this finding is apparent to some extent in the distal colon but not in the proximal colon. Chronic oral administration of cisapride, a gastrointestinal prokinetic drug, was effective to improve these gastrointestinal motility disorders in diabetics with autonomic neuropathy.

Administration, Oral↗

Probiotic Lactobacillus spp. diminish Helicobacter hepaticus-induced inflammatory bowel disease in interleukin-10-deficient mice.

Clinical and experimental evidence has demonstrated the potential role of probiotics in the prevention or treatment of inflammatory bowel disease. Probiotic clones with direct immunomodulatory activity may have anti-inflammatory effects in the intestine. We investigated the roles of tumor necrosis factor alpha (TNF-alpha)-inhibitory Lactobacillus clones with a pathogen-induced murine colitis model. Murine-derived probiotic lactobacilli were selected in vitro for their ability to inhibit TNF-alpha secretion by Helicobacter hepaticus-stimulated macrophages. Interleukin-10 (IL-10)-deficient mice were treated with probiotic Lactobacillus reuteri in combination with Lactobacillus paracasei and then challenged with H. hepaticus. Ten weeks postinoculation, the severity of typhlocolitis was assessed by histologic examination of the cecocolic region. Intestinal proinflammatory cytokine responses were evaluated by real-time quantitative reverse transcriptase PCR and immunoassays, and the quantities of intestinal H. hepaticus were evaluated by real-time PCR. Intestinal colonization by TNF-alpha-inhibitory lactobacilli reduced intestinal inflammation in H. hepaticus-challenged IL-10-deficient mice despite similar quantities of H. hepaticus in cocolonized animals. Proinflammatory colonic cytokine (TNF-alpha and IL-12) levels were lowered in Lactobacillus-treated animals. In this H. hepaticus-challenged IL-10-deficient murine colitis model, lactobacilli demonstrated probiotic effects by direct modulation of mucosal inflammatory responses.

Animals↗

Colonization of the intestinal tract of mice with Clostridium tetani.

Colonization of intragastrically inoculated Clostridium tetani in intestinal tract of mice was investigated by cultivation of daily stool samples and quantification of the bacilli over a period of 3 weeks. We found that most of the inoculum was excreted in the stool during the first 24 hr. The amount of C. tetani recovered on the second day after inoculation was very small. C. tetani apparently thrived in the intestinal tract when more than 6 log colony forming units (CFU) of tetanus spores had been inoculated. Otherwise, C. tetani colonized poorly in intestinal tract. Tetanus toxin was not detected in the stool nor in the contents of the small and large intestines 24 hr after 6.23 log CFU of tetanus spores had been inoculated. We concluded that the intestinal cavity of mouse is not a favorable environment for colonization of C. tetani under natural conditions.

Animals↗

Effect of parenteral antibiotic administration on persistence of vancomycin-resistant Enterococcus faecium in the mouse gastrointestinal tract.

A mouse model of vancomycin-resistant Enterococcus faecium (VRE) intestinal colonization was used to study the effect of different subcutaneous antibiotics on persistence and density of VRE colonization. Gastric inoculation of a clinical VanB VRE isolate, in conjunction with oral vancomycin in drinking water (250 microgram/mL), resulted in high-level VRE colonization (mean, 9.5 log10 cfu/g) in all 169 experimental mice. After discontinuation of oral vancomycin, the level of VRE in the stool specimens of mice receiving subcutaneous saline steadily decreased (mean, 3.59 log10 cfu/g at day 19). Subcutaneous vancomycin, clindamycin, piperacillin-tazobactam, ticarcillin-clavulanic acid, metronidazole, cefotetan, ampicillin, and ampicillin-sulbactam all promoted persistent high levels of stool VRE. Subcutaneous ceftriaxone, cefepime, ciprofloxacin, and aztreonam promoted increased VRE density to a lesser degree or not at all. Thus, in a mouse model, vancomycin and antibiotics with potent antianaerobic activity promoted persistent high-density intestinal VRE colonization, whereas antibiotics lacking potent antianaerobic activity did not.

Animals↗

Demonstration of Brachyspira aalborgi lineages 2 and 3 in human colonic biopsies with intestinal spirochaetosis by specific fluorescent in situ hybridization.

Sequences of known 16S rRNA genes, derived from sequence analysis of cloned 16S rDNA, were used to design a specific oligonucleotide probe targeting spirochaetes of Brachyspira aalborgi lineages 2 and 3. The probe was used with fluorescent in situ hybridization to study the involvement of these organisms in human intestinal spirochaetosis. Seventeen human colonic biopsies from Norway and Denmark with intestinal spirochaetosis caused by Brachyspira-like organisms different from the type strain of B. aalborgi (lineage 1) were examined. Application of the probe gave a positive signal in two Norwegian biopsies, whereas the 15 other biopsies were hybridization-negative. The positive reaction visualized the spirochaetes as a fluorescent, 3-5 microm-high fringe on the surface epithelium, extending into the crypts. The study verified the presence of B. aalborgi lineages 2 and 3 and identified the bacteria as an aetiological agent of human intestinal spirochaetosis.

Adult↗

[Pathological and ultramicrostructural changes of tissues in a patient with severe acute respiratory syndrome].

OBJECTIVE: To study the morphological, ultramicrostructural and pathological changes of tissues from a patient with severe acute respiratory syndrome (SARS). METHODS: One autopsy case of diagnosed SARS was investigated. Lung puncture was performed immediately after the patient died, and the autopsy was done after 12 h. The specimens from lymph nodes, spleen, small intestine, colon and bone marrow were studied by immunohistochemical technique. The antibodies used included CD20, CD45RO (UCHL-1), CD4, CD8, CD68 and CD34. RESULTS: The principal lesions of the SARS case consisted of acute lobular intrastitial pneumonia, hyaloid membranes of pulmonic alveoli and hyperplasia and shedding of alveolar epithelium of. Virus-like inclusions occasionally contained cytoplasm of the alveolar epithelium, which were positive by histochemical staining. The adjacent blood-vessels were changed by hyperplasia and enlargement. The structures of lymph nodes and spleen were damaged with lymph follicles depletion and splenic nodules atrophy. The specific changes included reduction of lymphocytes and hyperplasia of histiocytes, depletion of the follicles of small intestine and colon wall, decreased hyperplasia of the bone marrow and increased number of the megakaryocyte. Meanwhile, in the immunohistochemical study, CD(20)(+) B cells were fully expressed in lymph nodes and spleen, and the CD45RO (UCHL-1)(+) T cells were scatteredly expressed. The number of CD4(+) help T cell was markedly decreased, while the number of CD8+ poisonal T cells increased, and the ratio of the former and latter was no more than 0.5. Under the electronic microscopy observation, virus-like particles with 80 - 160 nm diameter and halo or garland envelope were found in mononuclear macrophage and cytoplasm of alveolar epithelium. CONCLUSION: The specific lesions of SARS consist of lobular intrastitial pneumonia with the formation of hyaline membranes of lung, haemorrhage, necrosis, inflammation of blood vessels and the damages of extralung lymphohemopioetic system. The damages were very similar to the pathological features of tissues infected by human immunodeficiency virus, in which numbers of T cells decreased and CD(4)(+) T cell/CD(8)(+) T cell ratio was no more than 0.5. According to the virus-like particles found in lung of the SARS case, it is considered that these virus-like particles may be a new kind of coronavirus which caused the "atypical pneumonia".

Humans↗

An outbreak of gentamicin-resistant Klebsiella pneumoniae: analysis of control measures.

In April 1978, a strain of gentamicin-resistant Klebsiella pneumoniae (GRK) was introduced into the neonatal intensive care unit of Henry Ford Hospital. An additional ten cases of GRK occurred over the subsequent 16 months and intestinal colonization occurred in up to 91% of admissions per month. All GRK were susceptible to amikacin and were capsular serotype 19. Though hand contamination of hospital personnel with GRK was documented, increased handwashing practices did not reduce colonization rates of neonates with the epidemic strain. Intestinal carriage persisted for up to ten months and could not be eradicated by administering oral colistin sulfate. Discontinuation of gentamicin and utilization of amikacin were associated with a significant reduction in colonization with GRK (p less than 0.05). However, the only control measure that prevented both new cases and colonization with the epidemic strain was the utilization of a strict cohort system.

Carrier State↗

Apparition of Clostridium sp. and Bacteroides in the intestine of the newborn delivered by cesarian section.

Anaerobic flora plays a key role in preventing intestinal colonization with potential pathogens. Nowadays, the mechanisms involved in the colonization resistance provided by the anaerobic microflora are to be clarified. Numerous factors seem to intervene in the regulation of the intestinal flora. The purpose of the present study was to correlate the presence or relative absence of Clostridium sp. and Bacteroides with the colonization by C. perfringens, which is involved in lethal infections in an immunologically compromised host. The intestinal bacterial colonization of 20 newborns delivered by cesarian section was assessed sequentially over the first 14 days of life. C. perifringens is a strongly reducing microorganism and undoubtedly causes a decrease in the oxidoreduction potential of the newborn feces favouring the subsequent colonization by other putrefactive bacteria. C. perfringens seems to be the precursor for installation of putrefractive bacteria, as Bacteroides and other Clostridium sp.

Anaerobiosis↗

Microbial colonization of the intestinal epithelium in suckling mice.

Colonization by indigenous microorganisms of the mucosal epithelia of the large bowels of suckling mice was followed by microbial culture techniques and by light, fluorescence, and electron microscopy. Certain microbes colonize in distinctive patterns the cecal and colonic epithelia in these mice. Coliforms and enterococci colonize the large bowel 7 to 9 days after birth and reach high population levels during the second week. During that period, these facultative anaerobes can be detected by immunofluorescence techniques in microcolonies in the mucin on the epithelium. During the third week, however, after their populations decline to the low levels characteristic of adult mice, coliforms and enteroccoci can be observed only infrequently in the mucous layer. Anaerobic fusiform-shaped bacteria appear in the mucous layers along with the microcolonies of enterococci and coliforms during the second week after birth. These anaerobes increase in numbers in the mucin until they form thick layers on the mucosal epithelium by the end of the third week. They remain in the mucous layer throughout the life of the normal mouse. Anaerobic spiral-shaped microbes also colonize the mucous layer on the cecal and colonic epithelium. But these organisms can be detected by immunofluorescence in 1-week-old mice, well in advance of the time the fusiform-shaped bacteria can be found. In the second week, the latter microbes co-inhabit the mucous layer with the spiral-shaped organisms. The fusiform- and spiral-shaped microbes remain associated in the mucin on the cecal and colonic mucosal epithelia into the adult life of mice.

Animals↗

The effect of oral non-absorbable antibiotics on the emergence of resistant bacteria in patients in an intensive care unit.

Critically ill patients admitted to the surgical intensive care unit since 1982 have been treated prophylactically with oral non-absorbable antibiotics combined with parenteral cefotaxime. A mixture of polymyxin E, tobramycin and amphotericin B has been administered via a nasogastric tube and also applied topically to the buccal mucosa. This regimen has proven to be highly effective in reducing the infection rate. The present study evaluated the occurrence of resistant bacteria with this regimen during a 30-month period, in 164 patients with multiple trauma. No increase in the percentage of patients with acquired drug-resistant Gram-negative bacilli was found during this period. Colonization of the oral cavity and/or gastro-intestinal canal by polymyxin E-resistant strains (invariably Proteus spp.) occurred in 8% of patients, and by tobramycin-resistant bacilli (Escherichia coli or Acinetobacter or Pseudomonas spp.) in 4%. Intestinal colonization with cefotaxime-resistant strains (e.g. Pseudomonas, Acinetobacter or Enterobacter spp.) was observed in 17 patients (10%). Of these strains 82% were eliminated within one week by the oral non-absorbable antibiotics. Colonization of the respiratory tract, urinary tract or wounds with cefotaxime-resistant Gram-negative bacilli occurred in only three patients (2%).

Adolescent↗

Variation of mucin distribution in the rat intestine, caecum and colon: effect of the bacterial flora.

The influence of the intestinal microflora on mucin types was studied in the small intestine, caecum and colon of conventional (CV) rats as compared to germ-free (GF) rats. A colorimetric method was used on purified water-soluble mucin extracted from mucosal scrapings and contents. Variations occurred between the three anatomical sites both in the mucosas and intestinal contents of GF rats. In CV rats, the presence of the bacterial flora led to different effects depending on the intestinal site: in the small intestinal mucosa, neutral and sulphomucins values were higher whereas sialomucin was much lower. Conversely, sialomucin was higher in the caecal and colonic mucosas and contents whereas sulphated mucins were decreased significantly in caecal contents and caecal and colonic mucosas. These variations in the contents may reflect the bacterial mucolytic activity and the effect of bacterial metabolites on the mucosa.

Animal Feed↗

Binding of a pure 125I-monoiodoleptin analog to mouse tissues: a developmental study.

The preparation of a pure 125I-labeled monoiododerivative of mouse leptin is described. This radiolabeled analog has been used to characterize and localize central and peripheral leptin binding sites (Ob-R) of the mouse at different stages of its development. The affinity values found in membrane homogenates of various mouse tissues are similar and range between 0.1 and 0.3 nM, indicating that all the Ob-R isoforms have a similar affinity. Leptin binding sites are highly expressed at the membrane level in lung, intestine, kidney, liver, and skin and to a lesser degree in stomach, heart, and spleen. Brain, thymus, and pancreas homogenates are devoid of any specific binding. The distribution of mouse Ob-R has also been explored by autoradiography and dipping techniques on whole mouse sections. In lung, leptin binding sites are located at the pulmonary parenchyma and at the bronchiolar epithelial level. Binding sites are expressed all along the digestive tract from the tongue to the rectum (esophagus, stomach, intestine, colon, and rectum). In muscular visceral structures (stomach, intestine, and bladder) the binding is mainly present in the lamina propria. During development, leptin receptors are early expressed in the liver, kidney, and bone. In the lung, the Ob-R level increased gradually from birth to adulthood where the expression is maximal. By contrast, leptin receptors located in the medulla of the kidney remain remarkably constant all along the development. A broad signal is present in cartilage and bone particularly in vertebrae, limb, and ribs. Interestingly, leptin receptors are barely detectable in the mouse brain except in the choroid plexus and leptomeninges, whereas in the rat brain leptin binding sites are located in the thalamus, the piriform cortex, the cerebellum (at the granular and molecular cell layer), and the pineal gland.

Animals↗

Extracellular superoxide production by Enterococcus faecalis requires demethylmenaquinone and is attenuated by functional terminal quinol oxidases.

The intestinal commensal bacterium, Enterococcus faecalis, is unusual among prokaryotic organisms in its ability to produce substantial extracellular superoxide. Transposon mutagenesis, allelic replacement, and electron spin resonance (ESR)-spin trapping showed that superoxide production and generation of derivative hydroxyl radical were dependent on membrane-associated demethylmenaquinone. Extracellular superoxide was generated through univalent reduction of oxygen by reduced demethylmenaquinone. Moreover, extracellular superoxide production was inhibited by exogenous haematin, an essential cofactor for cytochrome bd, and by fumarate, a substrate for fumarate reductase. As integral membrane quinol oxidases, cytochrome bd and fumarate reductase redox cycle demethylmenaquinone, and are necessary for aerobic and anaerobic respiration respectively. A rat model of intestinal colonization demonstrated that conditions exist in the mammalian intestinal tract that permit a mode of respiration for E. faecalis that results in the formation of hydroxyl radical. These results identify and characterize the mechanism by which E. faecalis generates extracellular free radicals.

Animals↗

Protection of mice from lethal endogenous Candida albicans infection by immunization with Candida membrane antigen.

The protective effects of immunization with Candida membrane antigen (CMA) on a systemic infection originating from intestinally colonized Candida albicans were examined. The colonization of orally inoculated C. albicans in the intestinal tract was established in BALB/c mice that had been concomitantly treated with oral doses of antibacterial drugs. In these animals, a systemic dissemination of C. albicans with fatal outcome was induced by a repeated dosing of prednisolone. In this endogenous infection model, the effects of immunization by CMA on the infection were examined. CMA-immunized mice showed a longer lifespan than unimmunized mice. The protective effect of CMA immunization in immunosuppressed mice was also measured by a decrease in body weight loss after treatment with prednisolone and in the number of viable Candida cells in the target organs, the kidneys and livers. However, the CFU of C. albicans in the intestinal tract was not significantly lowered. These results suggest that CMA immunization inhibited the dissemination of systemic Candida infection from the intestinal tract induced by treatment with prednisolone.

Animals↗

Lipid profile of Helicobacter spp.: presence of cholesteryl glucoside as a characteristic feature.

The lipid and fatty acid profiles of eight Helicobacter spp. (H. nemestrinae, H. acinonyx, H. canis, Helicobacter sp. strain CLO-3, "H. rappini" [Flexispira rappini], H. pametensis, Helicobacter sp. strain Bird-B, and Helicobacter sp. strain Bird-C) and the fatty acid profiles of five additional species (H. pylori, H. felis, H. muridarum, H. mustelae, and H. fennelliae) were analyzed and compared. A heterologous fatty acid profile was observed among the Helicobacter spp., and on that basis the species could be divided into two groups. Group A had 19-carbon cyclopropane fatty acid (19:0cyc) and tetradecanoic acid (14:0) as the major fatty acids, and group B characteristically lacked the 19:0cyc and had hexadecanoic acid (16:0) and octadecenoic (18:1) acids as the major fatty acids. The species of group A are primarily gastric colonizers, and those of group B are primarily intestinal colonizers. Seven of the eight species studied showed the unusual and characteristic presence of cholesteryl glucosides (CGs), and most of these seven showed a very large amount (9.7 to 27.4% of the weight of total extractable lipid). The types of CGs and their distribution in different species were as follows: cholesteryl-6-O-acyl-alpha-D-glucopyranoside (cholesteryl-6-O-tetradecanoyl-alpha-D-glucopyranoside in H. nemestrinae and mainly cholesteryl-6-O-dodecanoyl-alpha-D-glucopyranoside in "H. rappini"), cholesteryl-alpha-D-glucopyranoside (H. nemestrinae, H. acinonyx, H. canis, Helicobacter sp. strain CLO-3, and "H. rappini"), and cholesteryl-6-O-phosphatidyl-alpha-D-glucopyranoside (H. nemestrinae, H. acinonyx, H. canis, and Helicobacter sp. strain CLO-3). Besides this, we could also detect cholesteryl acyl glucoside in H. acinonyx, cholesteryl glucoside in Helicobacter sp. strains Bird-B and -C, and cholesteryl phosphatidyl glucoside in "H. rappini" and Helicobacter sp. strain Bird-C. A selective accumulation of free cholesterol was observed in the neutral lipid fractions. On the basis of the detection of CGs in 11 of the 13 species studied so far, the presence of CGs appears to be a characteristic feature of the genus Helicobacter. In view of this and also because of a simple and rapid detection method described herein, the CGs can be used as a valuable chemotaxonomic marker.

Cholesterol↗

[Solitary diverticulum of ascending colon induced internal intestinal herniation: report of one case].

Colonic diverticula are generally multiple and occur most commonly in the descending and sigmoid colon. Solitary ascending colonic diverticulum is a rare pathology and presents several features which separate it from colonic diverticulosis. It is a true diverticulum. It is a congenital dysplasia that generally runs an asymptomatic course and becomes clinically important only when inflammatory, perforating, or hemorrhagic complications occurs and presents a difficult problem in diagnosis and management. An unusual case of 4 year old girl with solitary ascending colonic diverticulum was reported here. It caused internal intestinal herniation by forming an adhesion band with mesentery and the clinical course manifested as an acute intestinal obstruction.

Child, Preschool↗