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PubMed2001

Immunological activities associated with milk.

Milk contains a multitude of components that can, or may, provide immune protection to the suckling offspring and that also may promote development of neonatal immune competence. In addition, these specialized factors are essential for the protection of the mammary gland, the offspring's food source, from pathogen colonization and lactation failure. Breast milk also facilitates the establishment of a gut flora that inhibits colonization by many pathogens and stimulates the growth of beneficial microorganisms. Maternal immunity can be transferred to the infant via antibodies, primarily of the sIgA type in humans, as well as by leukocytes including effector and memory T lymphocytes. In this way, protection is provided passively against the pathogens to which the mother has been exposed. Currently, there is much interest in determining the protective efficacy of oral supplementation with immunoglobulins from the milk of lactating animals hyperimmunized against specific pathogens. An array of immunostimulatory components in milk, notably cytokines, may be protected against intestinal proteolysis, thereby providing the offspring with a prepackaged immune response system. These components may help to boost the infant's immature immune system. At the same time, anti-inflammatory factors in breast milk help to modulate cytokine responses to infection, thereby facilitating defense while minimizing tissue damage such as that which occurs in infants with necrotizing enterocolitis. Undoubtedly, the many components constituting the repertoire of immune and immunomodulating agents in milk interact synergistically to protect both the mammary gland and the offspring from invading pathogenic microorganisms.

Animals↗
PubMed2005

Evidence of probiotics in prevention of allergy and asthma.

Previous research into the causes of allergic diseases was mostly focussed on potential risk factors in the environment, with little success, however. Over the past 10 years, focus has therefore more been directed against protective factors that could enhance the development of tolerance to allergens which were previously encountered early in life, but are now lost in modern affluent societies. In particular, the role of childhood infections has been discussed, but so far these studies have not been conclusive. Recent epidemiological studies and experimental research suggest that the microbial environment and exposure to microbial products in infancy modifies immune responses and enhances the development of tolerance to ubiquitous allergens. The intestinal microflora may play a particular role in this respect, as it is the major external driving force in the maturation of the immune system after birth and animal experiments have shown it to be a prerequisite for normal development of oral tolerance. The composition of the microflora differs between healthy and allergic infants and in countries with a high and low prevalence of allergies. These differences are apparent within the first week of life, or even in the maternal vaginal flora during pregnancy and thus precede clinical symptoms. The use of live microorganisms that might be beneficial to health has a long tradition and the safety is well documented. Prospective intervention studies, in which the gut flora was modified from birth have yielded encouraging results and may suggest a new mode of primary prevention of allergy in the future.

Asthma↗
PubMed2000

Identification of a novel bacterial sequence associated with Crohn's disease.

BACKGROUND & AIMS: Enteric microorganisms are implicated in the pathogenesis of Crohn's disease (CD), but no clear bacterial or viral species has been identified. In this study, representational difference analysis (RDA) was used to isolate DNA segments preferentially abundant in lamina propria mononuclear cells of lesional mucosa vs. adjacent uninvolved mucosa. METHODS: Two RDA-derived microbial sequences were isolated (I1 and I2) and identified as novel homologues of the ptxR and tetR bacterial transcription-factor families. RESULTS: Quantitative competitive polymerase chain reaction of paraffin-embedded intestinal specimens from 212 patients showed that I2 DNA was present in many CD colonic lesions (43%), but was infrequent in other colonic specimens (9% of ulcerative colitis lesions and 5% of non-inflammatory bowel disease diseases; P<0.0001). I2 was prevalent in ileal specimens, regardless of disease status (43%-54%). Enzyme-linked immunosorbent assay analysis of 150 individuals with an I2 glutathione-S-transferase fusion protein showed frequent immunoglobulin A seroreactivity in CD (54% of patients), but infrequent seroreactivity in patients with ulcerative colitis, other inflammatory enteric diseases, or normals (10%, 19%, and 4%, respectively; P<0.001 to 0.00001). CONCLUSIONS: These findings relate CD to a novel lesion-localized and immunologically associated bacterial sequence, suggesting that the microorganism expressing the I2 gene product may be related to CD pathogenesis.

Amino Acid Sequence↗
PubMed2005

Synbiotics reduce postoperative infectious complications: a randomized controlled trial in biliary cancer patients undergoing hepatectomy.

BACKGROUND AND AIMS: The clinical value of synbiotics in surgical patients remains unclear. The aim of this study was to investigate the effect of synbiotics on intestinal integrity and microflora, as well as on surgical outcome, in patients undergoing high-risk hepatectomy. METHODS: Fifty-four patients with biliary cancer were randomly allocated to two groups before hepatectomy. One group received postoperative enteral feeding that included synbiotics; the other received enteral feeding only. Lactulose/mannitol (L/M) ratio, serum diamine oxidase (DAO) activity, and fecal microflora and organic acid concentrations were determined. Postoperative infectious complications were recorded. RESULTS: Of the 54 patients, 44 completed the trial (21 receiving synbiotics and 23 others as controls). Postoperative changes in L/M ratios and serum DAO activities were identical between the two groups. Numbers of beneficial bacteria increased in the synbiotics group after surgery but decreased in controls. Numbers of harmful microorganisms decreased in the synbiotics group but increased in controls. Total organic acid concentrations increased in the synbiotics group but decreased in controls. Incidence of infectious complications was 19% (4/21) in the synbiotics group and 52% (12/23) in controls (P<0.05). All study patients tolerated surgery (mortality 0%). CONCLUSIONS: Synbiotics, combined with early enteral nutrition, can reduce postoperative infections. This beneficial effect presumably involves correction of an intestinal microbial imbalance induced by surgical stress.

Aged↗
PubMed1998

Mucosal immunogenicity elicited in mice by oral vaccination with phosphorylcholine encapsulated in poly (D,L-lactide-co-glycolide) microspheres.

Poly(D,L-lactide-co-glycolide) microspheres loaded with phosphorylcholine linked to thyroglobulin (PC-Thyr) as protein carrier were prepared. The entrapment efficiency reached 80% when the initial protein:polymer ratio was 1:8. Ninety-four percent of the loaded microspheres had a diameter < or = 10 microns. The encapsulation process did not alter PC-Thyr absorbance nor PC antigenic reactivity. Oral administration of these microspheres induced a specific IgA response in intestinal, pulmonary and vaginal secretions, as well as a strong specific systemic immune response in female Balb/c mice. This suggests the need to explore further the potential ability of PC-Thyr loaded microspheres to protect against infections caused by PC-bearing microorganisms which invade or colonize different mucosal sites.

Administration, Oral↗
PubMed2002

Probiotics and atopic dermatitis. A new strategy in atopic dermatitis.

Over the last few decades, the prevalence of atopic dermatitis has been increasing from 2% to 100%, with 90% of cases within 5 years of age versus 6% between 6 and 10 years and 2% after 10 years, and environmental factors may possibly play an important role in this increase as in other atopic diseases. Many findings suggest an important role of atopy in atopic dermatitis; moreover, 40% of children with atopic dermatitis have food allergy and the removal of the food allergen from the patient's diet leads to a significant clinical improvement. In a possible scenario, IgE-bearing dendritic cells are likely to process allergens acquired in the gastrointestinal tract, circulate to the skin and activate local T cells. Cultures of beneficial live microorganisms characteristic of the commensal microflora are administered with probiotic functional foods in order to provide a microbial challenge for the maturation of gut-associated lymphoid tissue, which the infant often lacks. The probiotic effects are attributed to normalisation of the increased intestinal permeability and balancing gut microecology, improvement of the immunological defence barrier (IgA) of the intestine, alleviation of the intestinal inflammatory response, and downregulation of proinflammatory cytokines characteristic of local and systemic allergic inflammation.

Child↗
PubMed2001

In vitro antibacterial activity of some aliphatic aldehydes from Olea europaea L.

In the present paper we report the 'in vitro' activity of eight aliphatic long-chain aldehydes from olive flavor (hexanal, nonanal, (E)-2-hexenal, (E)-2-eptenal, (E)-2-octenal, (E)-2-nonenal, (E)-2-decenal and (E,E)-2,4-decadienal) against a number of standard and freshly isolated bacterial strains that may be causal agents of human intestinal and respiratory tract infections. The saturated aldehydes characterized in the present study do not exhibit significant antibacterial activity, while the alpha,beta-unsaturated aldehydes have a broad antimicrobial spectrum and show similar activity against Gram-positive and Gram-negative microorganisms. The effectiveness of the aldehydes under investigation seems to depend not only on the presence of the alpha,beta-double bond, but also on the chain length from the enal group and on the microorganism tested.

Aldehydes↗
PubMed2003

Potential uses of probiotics in clinical practice.

Probiotics are defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. There is now mounting evidence that selected probiotic strains can provide health benefits to their human hosts. Numerous clinical trials show that certain strains can improve the outcome of intestinal infections by reducing the duration of diarrhea. Further investigations have shown benefits in reducing the recurrence of urogenital infections in women, while promising studies in cancer and allergies require research into the mechanisms of activity for particular strains and better-designed trials. At present, only a small percentage of physicians either know of probiotics or understand their potential applicability to patient care. Thus, probiotics are not yet part of the clinical arsenal for prevention and treatment of disease or maintenance of health. The establishment of accepted standards and guidelines, proposed by the Food and Agriculture Organization of the United Nations and the World Health Organization, represents a key step in ensuring that reliable products with suitable, informative health claims become available. Based upon the evidence to date, future advances with single- and multiple-strain therapies are on the horizon for the management of a number of debilitating and even fatal conditions.

Adult↗
PubMed2004

Antimicrobial resistance in commensal flora of pig farmers.

We assessed the quantitative contribution of pig farming to antimicrobial resistance in the commensal flora of pig farmers by comparing 113 healthy pig farmers from the major French porcine production areas to 113 nonfarmers, each matched for sex, age, and county of residence. All reported that they had not taken antiimicrobial agents within the previous month. Throat, nasal, and fecal swabs were screened for resistant microorganisms on agar containing selected antimicrobial agents. Nasopharyngeal carriage of Staphylococcus aureus was significantly more frequent in pig farmers, as was macrolide resistance of S. aureus from carriers. Nongroupable streptococci from the throat were more resistant to the penicillins in pig farmers. The intestinal isolation of enterococci resistant to erythromycin or vancomycin was not significantly higher in pig farmers in contrast to that of enterobacteria resistant to nalidixic acid, chloramphenicol, tetracycline, and streptomycin. Prevalence of resistance in predominant fecal enterobacteria was also significantly higher in pig farmers for cotrimoxazole, tetracycline, streptomycin, and nalidixic acid. We determined a significant association between pig farming and isolation of resistant commensal bacteria.

Adult↗
PubMedDate not supplied

[Microsporidiasis in AIDS patients with chronic diarrhea. Expieriences at the National Institute of Nutrition "Salvador Zubrirán"].

BACKGROUND: Microsporidium sp. has been considered as a rare cause of diarrhea in AIDS patients. However, the improvement of some histochemical stains in the analysis of small bowel biopsies has shown an increase in its prevalence. In Mexico there are no series reporting intestinal microsporidiasis. DESIGN: Small bowel biopsies of 98 patients with AIDS and chronic diarrhea stained with HE and Giemsa were reviewed (January 1987-December 1994). The clinical, demographic and laboratory information was obtained from the clinical charts. RESULTS: In 50 patients an opportunistic microorganism was identified in the small bowel biopsy (51%). Microsporidium sp. was identified in 30 patients (31%). The clinical charts were reviewed in all but six cases. Of the 24 patients with microsporidiasis as the cause of diarrhea, 17 were male and seven female with a median age, of 33 years, old. Homosexuality was the main risk factor in males (11/17), and blood transfusion in females (4/7). A low socioeconomical classification was found in 75% cases. The initial manifestation of AIDS was diarrhea in 16/24 (67%), CD4 count cell below 200 mm3 was identified in 13/24 patients and more than 200 mm3 in 2/24. The stool examination and the original histologic interpretations were negative for Microsporidium sp. Lymphoplasmocytic inflammatory infiltrate with eosinophils in the lamina propia and atrophy was frequently seen. A pale red and gray color was observed in spore and merogonial phases of Microsporidium stained with Giemsa. CONCLUSION: Microsporidium sp. was present as the only pathogen in 31% of the small bowel biopsies reviewed by light microscopy. Diarrhea due to Microsporidium sp. is frequently seen in advanced stages of AIDS with CD4 count cell below 200 mm3 Giemsa stain in the evaluation of small biopsies is a cheap and useful method to, identify Microsporidium sp.

AIDS-Related Opportunistic Infections↗
PubMed1992

[Surgical treatment of native valve endocarditis].

Twenty eight patients with native valve endocarditis (NVE) were subjected to this study. Thirteen patients underwent an operation at the chronic phase, and 15 patients at the active phase. One of the 13 patients at the chronic phase died of cardiac rupture due to myocardial infarction which had occurred preoperatively, and one of 10 patients at active phase without annular infection died of rupture of mycotic cerebral aneurysm early postoperatively. Among 5 patients at the active phase with annular infection, prosthetic valve endocarditis occurred in one patient 1.5 months after supraannular aortic valve replacement, and the second operation with a translocation technique was needed. This patient was lost from low output syndrome. Another patient in this group, who underwent a translocation technique because of mycotic annular abscess, died of intestinal infarction late postoperatively. The other 24 patients went a good postoperative course. Five patients with annular infection at the active phase had a shorter duration from the infectious onset to operation (20 days to 2 months, average 38 days), and the causative microorganisms were streptococcus faecalis, staphylococcus epidermidis and gram-negative coccus. One patient, who died of mycotic cerebral aneurysmal rupture, had candida albicans as a causative microorganism. For patients with NVE, an early aggressive operation is essential before infection extends to the annulus or to other vital organs, especially when these microorganisms are identified.

Adult↗
PubMedDate not supplied

[Concept of a probiotic preparation, containing original microbial metabolites].

The biological functions of Escherichia coli M-17 exometabolites, contained in the synthetic composition of the autostimulating preparation "Actoflor-C", were evaluated. As shown by in vitro experiments, the composition had higher stimulating activity with respectto some microorganisms of the normal microflora, in comparison with the prototype preparation "Actoflor". High doses of the preparation "Actoflor-C" were supposedly capable of having not only positive influence on the development of microbiocenosis, but also of producing therapeutic action and primarily on intestinal epithelial cells by compensating the insufficient supply of bacterial metabolites in dysbiotic states. The presented data made it possible to believe that the functional activity of microbiocenosis was greatly determined by the system of metabolic regulation. The presented results formed the basis for the use of bacterial metabolites in the therapeutic of microbiocenosis in man.

Bacteria↗
PubMed1985

[Etiology of intestinal Enterobacteriaceae infections in young children].

Enterobacteria, potentially capable of causing infections, were isolated from the feces of 88.7% of young children in the intestinal department of an infectious disease hospital. Opportunistic bacteria were considered to be the causative agents of infections only in cases of their high concentration in the material under test. In about a half of the cases the etiological role of the suspected microorganisms was confirmed by the detection of antibodies in low titers. The presence of maternal antibodies did not interfere with diagnostic procedures. The detection of antibodies to autocultures, even in a single case, is of diagnostic importance in the examination of young children. Autoserologically confirmed mixed infection was found to take a more prolonged course than autoserologically confirmed monoinfection.

Agglutination Tests↗
PubMed1984

N-nitrosamine formation by intestinal bacteria.

N-Nitrosamine formation by various intestinal bacteria was investigated. N-Nitroso-dimethylamine (NDMA) formation by viable resting cells of Escherichia coli A10 was proportional to the incubation time and the enzyme concentration, while boiled cells were incapable of nitrosation. The enzyme was optimal at pH 7.5 and showed about the same specificities for dimethylamine, diethylamine, dibutylamine, di-isobutylamine, piperidine and pyrrolidine, but high specificity for morpholine. The intestinal bacteria harbouring nitrosating enzyme were mainly aerobic, i.e., Escherichia coli, Proteus morganii, Klebsiella pneumonia and Pseudomonas aeruginosa. Only one of the 32 anaerobic intestinal bacterial species, i.e., Peptococcus asaccharolyticus, was positive. The enzyme activities of these nitrosating bacteria covered a range of 0.06-0.90 nmol NDMA formed per hour per mg protein. These results support the theory of enzymatic catalysis of N-nitrosamine formation by microorganisms and suggest the possibility of endogenous nitrosation in the digestive tract.

Dimethylnitrosamine↗
PubMed2001

The physiological expression of inducible nitric oxide synthase (iNOS) in the human colon.

BACKGROUND: Inducible nitric oxide synthase (iNOS) is expressed in the colonic epithelium in both inflammatory bowel disease and colorectal cancer. Nitric oxide (NO), the product of this enzyme, has been implicated in the pathogenesis of both conditions. However, there are conflicting data on whether iNOS is expressed in the normal, uninflamed human colon. AIMS: To evaluate the expression of iNOS in histologically normal, non-inflamed human colonic mucosa. PATIENTS/METHODS: Reverse transcription polymerase chain reaction (RT-PCR), immunoblotting, and immunohistochemistry were used to investigate the expression of iNOS in 17 histologically normal specimens obtained at colectomy performed for colorectal neoplasia. In addition, 16 endoscopic mucosal biopsies, taken from normal individuals, were also evaluated. Eleven surgical specimens and 16 endoscopic biopsies from patients with refractory ulcerative colitis were used as inflammatory controls. RESULTS: All types of specimens expressed iNOS mRNA. Immunoblotting revealed a protein of approximately 130 kDa consistent with iNOS in mucosal extracts of 77% of normal individuals, and 85% of diseased controls. Immunolabelling localised this protein to the surface epithelium in most of the normal specimens and also to the crypt epithelium and inflammatory cells in the diseased controls. CONCLUSIONS: These findings provide evidence that iNOS is often expressed in the surface epithelium of non-inflamed human colon, suggesting that it is induced by local luminal factors, such as bacterial lipopolysaccharide (endotoxin). The resultant NO produced at this site might act as an oxidative barrier, reducing bacterial translocation and providing a means of defence against pathogenic microorganisms.

Adult↗
PubMed1999

Mucin gene expression in the rat middle ear: an improved method for RNA harvest.

Mucins are heavily glycosylated proteins characterized by high molecular weight and heterogeneous structure. Mucin genes are expressed in a tissue- or epithelium-specific manner. Although mucins are known to be important structural components of the mucociliary transport system that protects epithelium against invading microorganisms, very little is known about mucin gene expression unique to the middle ear. This study demonstrated that middle ear messenger RNA specifically hybridized with rat MUC2 and human MUC2 (SMUC-41) complementary DNA probes. MUC3 and MUC5AC mucin genes, dominantly expressed in rodent intestine and trachea, were not detected in the rat middle ears in this study. The middle ear MUC2 messenger RNA harvested by lavage was characterized by a single transcript--unlike its counterpart in intestine and airways, which is characterized by polydispersity--suggestive of a better method for RNA analysis. It was concluded that rat middle ears possess a MUC2 mucin gene or homologue of human MUC2 (SMUC-41).

Animals↗
PubMedDate not supplied

[Incidence of sporadic cases of the most frequent intestinal infections in Castellon].

BACKGROUND: Intestinal infections are highly frequent processes of which solely a part are identified by the epidemiological monitoring systems. This study is aimed at estimating the incidence on the population, by age groups, of the sporadic intestinal infections diagnosed in one healthcare district in Castellón in the year 2000. METHODS: Based on the routine coprocultures, the basic demographic data for each patient was gathered for calculating the diagnosis and hospitalization rates. For children up to five years of age, the per annum rates were calculation for each microorganism. RESULTS: Campylobacter showed the highest rates (114.5 x 10(5)), followed by rotavirus (94.7) and Salmonella (83.0). Rotavirus is predominant among children under one year of age (3,194 x 10(5)), Campylobacter among those 1-4 year-olds, with a maximum of 3,850 x 10(5) among one-year olds, while Salmonella was predominant among all ages starting as of 5 years of age. The rates for cases hospitalized showed a different pattern, rotavirus ranking first (34.9 x 10(5)), Salmonella (21.7 x 10(5)) and Campylobacter (9.9 x 10(5)). With the exception of Salmonella, there were no outbreaks during the period under study. The predominance of Campylobacter was observed at the expense of the cases among children within the 1-4 age range who were not hospitalized. CONCLUSIONS: Up to 4 years of age, the distribution of the germs causing these infections differs every year. A knowledge of the descriptive epidemiology of these infections contributes to the study of the social impact thereof and provides support for delving deeper into some questions that are posed with a view to these diseases and the preventive aspects which can be implemented.

Adenoviridae Infections↗