Probiotic characterization of Lactobacillus isolates from canine faeces.

AIMS: There is interest in using probiotics such as Lactobacillus species to control canine intestinal infections. The bacterial species should be of canine intestinal origin exhibiting host specificity. Bacterial strains were isolated from dog faecal samples and characterized to select specific probiotics as dietary supplements in feed, promoting health status. METHODS AND RESULTS: Bacterial strains have been screened for their probiotic properties including survival to gastric and pancreatic juices and bile salts, resistance to antibiotics and antipathogenicity. Five of 14 isolated Lactobacillus strains were tolerant to gastric stress. They were also resistant to clindamycin and with a significant antimicrobial capacity towards the pathogenic strains tested, variable according to the strain. They were identified by morphological and molecular characterization comparing the 16S rRNA gene sequence with the blast database. Three strains were identified as Lactobacillus reuteri and two as Lactobacillus johnsonii. Sugar fermentation profiles and adhesion to HT29 epithelial cells have been in vitro verified on L. reuteri AI, chosen as probiotic candidate. Resistance to freeze-drying, production and subsequent in vivo administration evaluating strain permanence, were also performed. No loss of vitality has been recorded due to the freeze-drying process. The average value of recovery percentage of L. reuteri AI at the end of the administration period and after 1 week of follow-up was respectively 26·7 and 17·4% of the total Lactobacillus sp. CONCLUSIONS: Among several selected probiotic strains, L. reuteri AI proved to be the best probiotic candidate to use as a supplement for dogs. SIGNIFICANCE AND IMPACT OF THE STUDY: Control of intestinal pathogenic micro-organisms in dogs is a growing concern and the selection of autochthonous probiotic bacterial strains to overcome some of the gut problems associated with the modern domestication of animals is a valuable tool.

Abusive use of antibiotics in poultry farming in Cameroon and the public health implications.

The types and methods of use of antibiotics in poultry farms in Cameroon, residual levels and potential microbial resistance were determined. A questionnaire-based survey identified the different antibiotics used and high-performance liquid chromatography (HPLC) was used to determine residual levels of antibiotics. Pathogens were isolated, identified by use of commercial API kits and minimum inhibition concentration (MIC) was determined. Oxytetracyclin, tylocip and TCN (oxytetracycline, chloramphenicol and neomycin) were the most frequently used antibiotics. Antibiotics screened by HPLC were chloramphenicol, tetracycline and vancomycin. All of them except vancomycin were detected, and the concentration of these antibiotics was higher than the maximum residual limits (MRL) set by regulatory authorities. No residues of various antibiotics were found in egg albumen or yolk. The concentration of tetracycline was significantly higher in liver (150 ± 30 µg/g) than in other tissues. Foodborne pathogens, including Salmonella spp., Staphylococcus spp., Listeria spp., Clostridium spp. and Escherichia spp., were identified. Most of the pathogens were resistant to these various antibiotics tested. These findings imply the need for better management of antibiotic use to control sources of food contamination and reduce health risks associated with the presence of residues and the development of resistant pathogens by further legislation and enforcement of regulations on food hygiene and use of antibiotics.

In vitro evaluation on HeLa cells of protective mechanisms of probiotic lactobacilli against Candida clinical isolates.

AIMS: To characterize in vitro the ability of human Lactobacillus strains to inhibit the adhesion, to displace and to compete with clinically isolated Candida strains. METHODS AND RESULTS: Three types of assays were performed to determine the inhibitory effect of Lactobacillus plantarum 319, Lactobacillus rhamnosus IMC 501, Lactobacillus paracasei IMC 502 and a specific probiotic combination (SYNBIO) on adhesion of Candida pathogens to HeLa cells: blockage by exclusion (lactobacilli and HeLa followed by pathogens), competition (lactobacilli, HeLa and pathogens together) and displacement (pathogens and HeLa followed by the addition of lactobacilli). Bacterial adhesion to HeLa was quantified by microscopy after May-Grünwald/Giemsa stain. The inhibition results highlight a significant (P < 0·05) competition of the considered probiotics against all the Candida strains. The results suggest that the probiotic strains used in this study could prevent colonization of the urogenital tract by relevant pathogens such as Candida strains through barrier and interference mechanisms (mainly displacement and competition), but the degree of inhibition of adhesion was bacterial strain-dependent. CONCLUSIONS: The results support the potential of these Lactobacillus probiotic strains as anti-infective agents in the vagina and encourage further studies about their capacity to prevent and manage urogenital tract infections in females. SIGNIFICANCE AND IMPACT OF THE STUDY: To optimize the defensive properties of the vaginal microbiota, improving the health of many women by probiotic intervention.

Evaluation of antipathogenic activity and adherence properties of human Lactobacillus strains for vaginal formulations.

AIMS: To test different Lactobacillus strains for their antipathogenic activity towards Candida strains and their adhesion properties for the preparation of vaginal ovules and douches to be used in vaginal candidiasis prevention. METHODS AND RESULTS: Five strains of lactobacilli were tested for their antimicrobial potential against different clinically isolated Candida strains. They were also screened for their ability to produce hydrogen peroxide and to coaggregate with pathogens. Adhesion properties of the five different Lactobacillus strains to HeLa cells and the presence of arcA gene were also assessed. The in vitro experiments demonstrated that all the five Lactobacillus strains tested possessed inhibitory action against the Candida strains using the radial streak method, but the effect is strain dependent. The same situation arises with regard to the ability of coaggregation that is present in all the strains into different degrees. Only Lactobacillus rhamnosus IMC 501(®) and Lactobacillus paracasei IMC 502(®) were able to produce H2O2 and none of the strains possess arcA gene. The most adherent strains to HeLa cells were Lact. rhamnosus IMC 501(®), Lact. paracasei IMC 502(®) and also their combination SYNBIO(®). This latter was selected for the preparation of ovules and douches using different matrix. Witepsol(®) ovules have proved the best formulation in terms of probiotic viability. CONCLUSIONS: Lactobacillus rhamnosus IMC 501(®), Lact. paracasei IMC 502(®) and SYNBIO(®) were able to produce H2O2, to coaggregate and to exert antimicrobial activity against pathogenic Candida strains and to strongly adhere to HeLa cells. All these properties together with those technological make these strains good candidates for the realization of formulations suitable for vaginal health. SIGNIFICANCE AND IMPACT OF THE STUDY: To develop new vaginal formulations taking into account the impact of probiotic strains on pathogens as well as the technological properties of the strains to validate their effectiveness in human health.

In vitro evaluation of antimicrobial activity of Lactobacillus rhamnosus IMC 501(®) , Lactobacillus paracasei IMC 502(®) and SYNBIO(®) against pathogens.

AIMS: Probiotic lactobacilli have a great potential to produce antimicrobial compounds that inhibit and control the microbial pathogen growth. The antimicrobial and antifungal activities of two probiotic strains, Lactobacillus rhamnosus IMC 501(®) and Lactobacillus paracasei IMC 502(®) , and their 1 : 1 combination, named SYNBIO(®) , were studied using four different methods. METHODS AND RESULTS: Using two modified streak methods and a well diffusion method, the inhibitory activity of the probiotics and their metabolites towards six Gram-positive, nine Gram-negative pathogenic bacterial strains and eight Candida strains was tested. Antagonistic effect of probiotic Lactobacillus strains was also investigated by coculturing assay highlighting a significant inhibition of most of the pathogens tested in this study. The combination SYNBIO(®) showed a microbicidal activity against most of the strains tested in the study. CONCLUSIONS: Compared with the control, most of the pathogenic bacteria and yeast were inhibited by all probiotic strains tested to various degrees. SIGNIFICANCE AND IMPACT OF THE STUDY: Screening Lactobacillus strains according to their activity in various environmental conditions could precede the clinical efficacy studies for adjunct treatment with probiotics in cure of different gastrointestinal and vaginal tract infections.

Influence of a combination of two potential probiotic strains, Lactobacillus rhamnosus IMC 501® and Lactobacillus paracasei IMC 502® on bowel habits of healthy adults.

AIMS: This study aims to investigate the effect of different kinds of food products enriched with a combination of two potential probiotic strains, Lactobacillus rhamnosus IMC 501(®) and Lactobacillus paracasei IMC 502(®), on bowel habits of healthy adults. METHODS AND RESULTS: Fifty healthy volunteers took part in a double-blind placebo probiotic feeding study (25 fed probiotics, 25 fed placebo) for 12 weeks. Each volunteer ingested daily one or more food products enriched with a combination of the two potential probiotic strains (probiotic group) or the same food products without the probiotics (control group). Faecal samples were collected before, at the end and 2 weeks later the intervention period, and some of the main groups of faecal bacteria were enumerated by plate count and real-time PCR. Questionnaires on bowel habits were submitted to volunteers. After the intervention, a significant increase in faecal lactobacilli and bifidobacteria were observed in the probiotic group, and stool frequency and stool volume were higher in the probiotic group than in the placebo group. CONCLUSIONS: Daily consumption of food products enriched with the two potential probiotic strains, Lact. rhamnosus IMC 501(®) and Lact. paracasei IMC 502(®) , contributes to improve intestinal microbiota with beneficial properties and enhances bowel habits of healthy adults. SIGNIFICANCE AND IMPACT OF THE STUDY: The study revealed that Lact. rhamnosus IMC 501(®) and Lact. paracasei IMC 502(®) exert a positive effect, in terms of improved bowel habits, on healthy adults.

A survey on the use of antibacterial in orthopaedic surgery.

The aim of this study is the comprehensive (pre-operative, operative and post-operative) evaluation of the use of antibacterial drugs on a group of patients subjected to orthopaedical surgery. The data regarding 1000 orthopaedic surgical operations, corresponding to 1000 non-urgent patients, have been examined. This study reveals the incongruity in the use of antibacterial drugs in the orthopaedic surgical activity mainly in operative prophylaxis, but also the administration during the intra-operative period, and the use of the same drugs in the post operative period.

Ultrasound-computerized tomography in neonatal encephalic pathology.

The echoencephalographic examinations of 127 neonates were analysed to verify the role of US in the study of neonatal cerebral pathology, and to compare it with CT. US was of value in identifying the existence of a cerebral lesion and for follow-up. CT was more reliable for the characterization of the lesion and in establishing the surgical indications.

Effect of intravenous administration of fluids on packed cell volume, blood pressure, and total protein and blood glucose concentrations in healthy halothane-anesthetized dogs.

OBJECTIVE: To determine the effects of IV administration of fluids on PCV, serum total protein and blood glucose concentrations, and systolic arterial pressure in healthy anesthetized dogs undergoing elective surgical procedures. DESIGN: Prospective, randomized controlled trial. ANIMALS: 70 clinically normal dogs. PROCEDURE: Dogs received i.v. administration of 0, 5, 10, or 15 mL/kg of body weight/h of a polyionic crystalloid solution or 5% dextrose in water. Blood samples were collected before and after administration of medication, prior to anesthetic induction, after anesthetic induction, at the end of the surgical procedure, and 2 hours after surgery to determine PCV and serum total protein and blood glucose concentrations. Blood pressure was measured before and after anesthetic induction and at the end of the surgery. RESULTS: There were not any significant differences in PCV, total protein concentration, or systolic arterial pressure among treatment groups. Hyperglycemia developed in dogs receiving 5% dextrose in water, but resolved 2 hours after discontinuing administration of fluids. CLINICAL IMPLICATIONS: Intravenous administration of fluids may not be necessary to maintain normal blood pressure in young, healthy dogs undergoing elective surgery.

Abnormal leucocyte locomotion induced by haemodialysis membranes. A clue to dialysis leucopenia.

In a study on polymorphonuclear leucocyte (PMN) chemotaxis and random locomotion carried out on 16 patients undergoing haemodialysis and on the same functions in normal PMN which were separated from plasma and subjected to laboratory haemodialysis, it was shown that random PMN locomotion is reduced and that there is a concomitant fall in the leucocyte count in haemodialyzed patients. The laboratory haemodialysis demonstrated that serum factors were not responsible for the PMN dysfunction, which lasted for the entire period of the procedure. The changes were observed only when cellulose membranes were used, and not when haemodialysis was performed with polyacrilonitrile membranes. The reduction in random PMN locomotion may be involved in the genesis of dialysis leucopenia, as well as in the increased susceptibility of uremic patients to infections.

Stimulation of polymorphonuclear leukocyte chemotaxis by cold precipitable complexes containing DNA-anti-DNA in active nephritis of systemic lupus erythematosus.

DNA-anti-DNA cold precipitable complexes (CPC) isolated from 21 patients with systemic lupus erythematosus were tested for their ability to stimulate polymorphonuclear leukocyte (PMN) chemotaxis and to activate complement in vitro. The complexes activated complement in 20 out of 21 cases and stimulated PMN chemotaxis in 13 out of 21. The stimulation of chemotaxis was present in the majority of patients with renal involvement (10 out of 13) and active disease (8 out of 9), while being almost negligible in those without renal involvement or active disease. In patients studied sequentially, CPC-stimulated chemotaxis was reduced to nil with the remission of the disease. CPC appears to play a pathogenic role in active systemic lupus erythematosus with renal involvement.

Prevalence of HCV infection among health care workers in a hospital in central Italy.

Health care workers are at risk of acquiring transmissible diseases. Controversial results have been reported about HCV. The aims of the present study are to assess the prevalence of HCV in health care workers in Pistoia General Hospital (central Italy) and to compare prevalence with other groups, particularly with a sample of the general population. Serum samples collected from 511 health care employees engaged in direct clinical task and 222 clerical and nurse school attendees have been tested by ELISA and confirmed by RIBA. Total seroprevalence was 3.8%:4.7% in the first group; 1.8% in the second group. The data showed a slight increase in prevalence by age and not by length of stay in the health care workers' group. Comparison of HCV prevalence with blood donors from the province of Pistoia and the general population from Sersale (Catanzaro, southern Italy), restricted to under-40 subjects, indicates an increasing trend in this order: Blood donors, general population, clerical and nursing school attendees, health care workers' group with the highest value (3.4%). A cohort study is needed to evaluate pattern of HCV seroconversion.

11-Oxycorticosteroid-dependent antibody in the serum of a patient with bladder neoplasm.

An IgM 11-oxycorticosteroid-dependent antibody was identified in the serum of a patient with bladder malignancy, which at 4-37 degrees C reacted with all the 11-oxycorticosteroids tested but not with desoxycorticosterone, testosterone, nortestosterone and progesterone. The resulting drug-antidrug antibody complex combines nonspecifically with red blood cells causing agglutination. This reactivity is enhanced both by acid pH and by high drug solution concentrations as well as by ficin test. The antibody is complement-independent and has no blood group specificity. No in vivo or in vitro hemolysis was observed.

Effects of antimicrobial treatment on fiberglass-acrylic filters.

AIMS: The aims of the present study were to: (i) analyse a group of antimicrobial agents and to select the most active against test microbial strains; (ii) test the effect of the antimicrobial treatment on air filters in order to reduce microbial colonization. METHODS AND RESULTS: Different kinds of antimicrobial agents were analysed to assess their compatibility with the production process of air filter media. The minimal inhibitory concentration for each antimicrobial agent was determined against a defined list of microbial strains, and an antimicrobial activity assay of filter prototypes was developed to determine the most active agent among the compatible antimicrobials. Then, the most active was chosen and added directly to the filter during the production process. The microbial colonization of treated and untreated filter media was assessed at different working times for different incubation times by stereomicroscope and scanning electron microscope analysis. Some of the antimicrobial agents analysed were more active against microbial test strains and compatible with the production process of the filter media. Filter sections analysis of treated filter media showed a significantly lower microbial colonization than those untreated, a reduction of species both in density and varieties and of the presence of bacteria and fungal hyphae with reproductive structures. CONCLUSIONS: This study demonstrated the ability of antimicrobial treatments to inhibit the growth of micro-organisms in filter media and subsequently to increase indoor air quality (IAQ), highlighting the value of adding antimicrobials to filter media. SIGNIFICANCE AND IMPACT OF THE STUDY: To make a contribution to solving the problem of microbial contamination of air filters, by demonstrating the efficacy of incorporating antimicrobial agents in the filter media to improve IAQ and health.

[Transfusion evaluation measured by a retrospective audit]. / Evaluación transfusional mediante audit retrospectivo.

From a sample of 759 transfusions requests (2123 Units) for 392 patients, evaluated by retrospective audits the incidence of inappropriate transfusion at our Hospital was found to be 25.8% of request, affecting 23.3% of units and 39.3% of patients. The most frequent causes were: non-surgical and surgical use of whole blood in patients without hypovolaemia, use of fresh frozen plasma in patients with normal coagulation study red blood cells transfusion in patients with chronic anaemia and haematocrit of 24-30% without risk factors, surgical overtransfusion and prophylactic platelet transfusion in patients with platelet count above 20 x 10(9)/L. 17.3% of units could have been saved, and 32.3% of patients were overexposed or unnecessarily exposed to the risks inherent in any transfusion.

Insights into the cryoprotective mechanism of dimethyl sulfoxide for phospholipid bilayers.

Dimethyl sulfoxide (Me2SO) is a widely used cryoprotectant for biological structures such as membranes. Despite hundreds of studies on the effects of this molecule, surprisingly little is known about its cryoprotective mechanism. This study investigates the ability of various Me2SO analogs to serve as cryoprotectants for liposomes. The data show that an increase in hydrophobicity progressively reduces the cryoprotective effect of sulfoxides. Additional experiments using phospholipid vesicles of varying composition demonstrate the Me2SO is markedly less effective on liposomes carrying a net negative charge. In fact, cryoprotection by Me2SO was virtually eliminated in vesicles composed of 30% phosphatidylserine (a negatively charged lipid). Based on these results, we suggest that the polar sulfoxide moiety of Me2SO interacts electrostatically with phospholipid membranes and that this interaction is critical for Me2SO's cryoprotective effect for membranes.

Efficacy of antimicrobial filter treatments on microbial colonization of air panel filters.

AIMS: To assess the activity of biostatic agents on the microbial colonization of panel filters. METHODS AND RESULTS: Microfibre glass acrylic filters, both used and unused, were examined for the presence of microorganisms. Test strains were used to verify microbial colonization of filter media. Antimicrobial agents were applied to the filter media and tested for their ability to reduce microbial colonization. The integrity of the panel filters and the antimicrobial activity trends of the filter media treated with antimicrobials were verified. A filtration efficiency test was carried out on the treated filters to evaluate filtration performance. Filters treated with antimicrobials demonstrated markedly less microbial colonization (density and varieties of species), higher filtration efficiency and delayed deterioration of the filter. CONCLUSIONS: The most important results of this study are the demonstration of preservation of the integrity of the filters and the lower release of microorganisms from treated filters. SIGNIFICANCE AND IMPACT OF THE STUDY: These results contribute to the resolution of problems concerning the microbial contamination of panel filters in the heating, ventilating and air-conditioning systems commonly used in the electronic industry, pharmaceutical industry, hospitals and other environments where the absence of contaminating particles and microorganisms is required.

[Post-transfusion purpura. Description of 2 cases diagnosed at the same hospital in a 6-month period]. / Púrpura postransfusional. Descripción de dos casos diagnosticados en un mismo hospital en un periodo de seis meses.

Two new cases of postransfusional purpura diagnosed at the same hospital within the space of six months are described. This finding supports the idea that despite being an infrequent disorder, a substantial rise in PTP cases inside and outside our country, has been recorded. This increase has coincided with a greater interest in platelet immunology and, particularly, in complications associated with blood transfusion. Both cases constitute an example of the clinical epidemiological profile which characterizes the patients suffering from this disorder. The patients are two women aged 74 and 60 years who after 8 and 9 days, respectively, of being transfused with red cells developed a severe thrombocytopenia accompanied by generalized haemorrhagic diathesis. The serological studies performed revealed the presence, in both patients, of an HPA-1a platelet specific antibody. The platelet genotyping enabled us to confirm this specificity after detecting an HPA-1 (a-b+) platelet genotype. The treatment with immunoglobulins at high doses proved to be effective in both cases. The adsorption-elution experiments of the antibody versus HPA-1 (a + b) platelets were positive in the patient with the highest antibody titre (1024). This finding support the most recent hypothesis concerning the pathogenic mechanism of PTP. According to this theory, the antibody, which is detected in the acute phase of the PTP, would not yet have acquired the restricted specificity corresponding to it. This could enable it to react with a structure shared by the HPA-1a positive and HPA-1a negative platelets.

Effects of protein perturbants on phospholipid bilayers.

Series of alcohols, amides, ureas, and sulfoxides with increasingly longer hydrocarbon chains have been shown to lower progressively the thermal denaturation temperature of proteins. This effect is presumably due to a hydrophobic interaction between the solute and nonpolar domains of the protein. Theoretically, these interactions should occur between the solute and any macromolecular structure having a nonpolar region to which the solute has access. A recent review by Arakawa et al. has summarized evidence for such an interaction between organic solutes and proteins and suggested that these interactions are favored at higher temperatures. The present study investigates the effects of several classes of compounds on the stability of phospholipid vesicles. The results show that many compounds that are known to perturb protein function also destabilize phospholipid bilayers as reflected by solute-induced loss of vesicle contents.