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PubMed1989

Microbiological profile of selected samples of "Al-Kohl" eye cosmetics in northern Jordanian provinces before and after use.

Fifty items of Al-Kohl collected from northern Jordanian provinces representing: 20 unopened ready to use samples purchased from retail outlets, 20 in-use samples obtained from ladies of different socioeconomic standards and 10 samples of the original stones (used for Al-Kohl preparation) were examined for their microbial contents. Ready to use and in-use samples were much more contaminated than the original stones. On sterility testing, more than 85% of the unused and in-use samples were contaminated with bacteria and or fungi comparing to 50% of the original stone samples. Quantitatively, 90% of the original stones contained less than 100 bacterial or fungal cells/g and the other remaining 10% were in the range of 10(2)-10(3) cfu/g either for bacterial or fungal counts. The level and distribution of the viable microbial counts in unused and in-use samples were comparable and much higher than original stones. More than 70% and 20% of those items contained more than 100 cfu/g of bacteria and fungi respectively. Among those samples 20% and 5% were heavily contaminated (contain more than 10(4) cfu/g) with bacteria and fungi respectively. Coliform bacteria in a number of 100 cfu/g or more were recovered from 10% of the unused and 20% of the in-use samples, none were recovered from original stones. The results of qualitative tests for identification of isolated microorganisms showed that 7 different species of Bacillus were found in the 50 examined samples. Approximately 50% of the examined samples contained Bacillus spp., Staphylococcus spp., Pseudomonas spp., P. vulgaris, S. marcescens were recovered from unused and in-use samples in different percentages, none from original stones, some of the detected Staphylococcus were aureus type and also one isolate of P. aeruginosa was detected in one of the in-use samples. The relationship between the detected level of microbial contamination in the tested samples with the proposed allowable international limits of contamination as well as the possible sources of contamination and the hygienic implications of using such products by the public were discussed.

Bacillus↗

PubMed1995

Microbial colonization of large wounds.

This study determines the nature of microbial wound colonization in 28 patients with large burns admitted to the Burn Centre, Haukeland University Hospital, Bergen. Altogether, 748 swabs were taken in 141 sampling procedures. A total of 414 microbial isolates were detected and their resistance patterns to a variety of systemic antimicrobial agents determined. The most frequent isolates were coagulase-negative staphylococci (21.5 per cent) and Staphylococcus aureus (14 per cent), followed by Enterococcus species (11.3 per cent), Pseudomonas aeruginosa (10.9 per cent) and Candida species (9.7 per cent). Forty-one per cent of the enterococci and 36 per cent of the coagulase-negative staphylococci were resistant to the aminoglycosides routinely given in conjunction with surgery in our ward. Only four of the 89 strains of coagulase-negative staphylococci were insensitive to methicillin, and no Staph. aureus were methicillin resistant. The time-related changes of burn wound colonization showed that on admission and during the first week, staphylococci and alpha-haemolytic streptococci were dominant. During the next weeks, these bacteria were gradually superceded by enterococci, gram-negative opportunists (mainly Pseud. aeruginosa, Acinetobacter calcoaceticus and Escherichia coli) and Candida species. The nature of microbial wound colonization and how the flora changes with time should be taken into consideration by those treating thermally injured patients.

Adolescent↗

PubMed2006

Usefulness of 23S rRNA amplification by PCR in the detection of bacteria in CAPD peritonitis.

BACKGROUND: Peritonitis is the most common complication of continuous ambulatory peritoneal dialysis (CAPD), and the spectrum of organisms causing CAPD peritonitis is broad. Polymerase chain reaction (PCR) has recently broadened its diagnostic capabilities in infectious diseases. PCR can provide a sensitive method for identifying causative infectious organisms. METHODS: To evaluate the usefulness of 23S bacterial ribosomal RNA amplification and direct sequencing for the detection of infectious organisms, we compared PCR with bacteriological culture for the analysis of dialysates from CAPD peritonitis patients. Thirty-two samples from CAPD peritonitis patients with current antibiotic use and control samples from 30 CAPD patients without peritonitis were examined by PCR with sequencing analysis and by conventional bacteriological culture. In addition, 95 culture-positive samples and 39 culture-negative samples from CAPD peritonitis patients before antibiotic treatment were analyzed by PCR assay. RESULTS: In the control samples from patients without CAPD peritonitis, false-positive rates were relatively rare: 3 of 30 in the PCR study and 2 of 30 in the culture study. Of the 134 CAPD peritonitis samples collected before antibiotic therapy, positive cultures were obtained in 70.9% (95/134) of them. In 75 of the culture-positive samples, the same microorganisms were confirmed by PCR assay, and the others showed discrepant results as compared with culture study. In 30 of the 39 culture-negative samples, microbial organisms were detected by PCR assay. Of the 32 samples from patients who developed CAPD peritonitis during antibiotic treatment, 17 (53.1%) were positive by PCR assay, and 5 (15.6%) were positive by culture. CONCLUSION: Our study suggests that broad-spectrum PCR with RNA sequencing can complement culture methods in the diagnosis of CAPD peritonitis, especially in patients with previous or current antibiotic use.

Adult↗

PubMed2006

Dispersal limitations matter for microbial morphospecies.

In contrast with macroorganisms, whose geographical ranges are typically restricted, many microbial species appear to have cosmopolitan distributions. This observation has been explained as a consequence of ubiquitous dispersal caused by the enormous population sizes of microbial species. Recently, this "everything is everywhere, but, the environment selects" theory has been challenged by the detection of considerable regional genetic variability within microbial morphospecies. We demonstrate that, contrary to what is expected under ubiquitous dispersal, evidence of regional-scale metacommunity processes can be detected in microbial morphospecies. Our results imply that the microbial and macrobial world are structured by analogous processes.

Biodiversity↗

PubMedDate not supplied

Detection of bacteria in equine synovial fluid by use of the polymerase chain reaction.

Equine synovial fluid aliquots were inoculated with Salmonella enteritidis, Escherichia coli, Actinobacillus equuli, Staphylococcus aureus, and Streptococcus zooepidemicus to obtain approximate concentrations of 1000, 100, 10, and 1 colony forming U/mL. Synovial fluid aliquots were also inoculated with an unquantitated inoculum of Bacteroides fragilis and Clostridium perfringens. Inoculated synovial fluid was incubated in trypticase-soy broth or Columbia broth for approximately 12 hours. Then aliquots were removed for DNA extraction and polymerase chain reaction (PCR) analysis for detection of a 531 base-pair segment of bacterial DNA corresponding to a region of the 16S ribosomal gene. Duplicate samples of inoculated synovial fluid were prepared for microbial culture. Bacteria were detected in all samples inoculated with bacteria but not in control synovial fluid samples. Under experimental conditions there was no difference between microbial culture and PCR analyses for detection of bacteria. Experimentally, PCR was able to detect bacteria in synovial fluid within 24 hours of inoculation.

Actinobacillus↗

PubMed1990

[Antibiotics in the treatment of wounds in the victims of the earthquake in the Armenian SSR].

Purulent wounds in 88 victims of the Armenian earthquake with the syndrome of long-term squeezing were examined microbiologically and the experience with using antimicrobial drugs for their treatment was analyzed. In all the cases microbial associations were detected, coliform and nonfermenting gram-negative bacilli, enterococci, anaerobes and yeast-like fungi being isolated from 80, 20, 15 and 25 per cent of the patients respectively. 130 bacterial strains were studied in detail. 80 to 100 per cent of the bacterial isolates were resistant to the antibiotics routinely used in surgical practice, i.e. benzylpenicillin, tetracycline, levomycetin, kanamycin, cephalothin and cefazolin and highly sensitive to new antimicrobial drugs belonging to ureidopenicillins (mezlocillin), quinolones (ciprofloxacin) and cephalosporins of the 3rd generation (cefoperazone and ceftazidime). Retrospective estimation of the antibiotic therapy revealed its inadequacy in 55.7 per cent of the patients for the most part because of the isolates resistance. The 19 variants of the antibiotic use prescribed by the physicians mainly included penicillins, aminoglycosides and their combinations (in 67.2 per cent of the cases). The use of the highly efficient drugs of the groups of ureidopenicillins and quinolones was extremely rare which was likely due to lacking of information on the drugs.

Anti-Bacterial Agents↗

PubMed2004

Mini-review: the role of peptidoglycan recognition in innate immunity.

The importance of peptidoglycan detection in the host innate immune response has long been underestimated. However, the recent identification of proteins involved in the sensing of peptidoglycan in both mammals and Drosophila has revealed that the detection of this microbial motif is key to the defense response. In Drosophila, the peptidoglycan-recognition proteins (PGRP) are the initial sensors of infecting bacteria that then trigger a cascade ultimately leading to the expression of antimicrobial peptides. In mammals, PGRP also exist and although they bind peptidoglycan, the role of these proteins in innate immune responses remains to be clearly defined. In contrast, the Nod proteins (Nod1 and Nod2), which are also involved in peptidoglycan sensing, appear to play a key role in innate immunity against bacteria by triggering host defense responses through the activation of the transcription factor, NF-kappaB. Interestingly, mutations in Nod2 are related to increased susceptibility to Crohn's disease, thereby implicating defective bacterial sensing in the development at this chronic disease. In this review, we will focus on the recent findings concerning mammalian and Drosophila proteins involved in peptidoglycan recognition and the putative role of these proteins in the innate immune defense response.

Animals↗

PubMed1984

Toxicity of dicamba (2-methoxy-3,6-dichlorobenzoic acid) to Azotobacter vinelandii.

The effect of dicamba was studied in N-free medium inoculated with Azotobacter vinelandii ATCC 12837. Nitrogen fixation was determined by acetylene reduction. Dicamba at a concentration of 500 micrograms/mL had a strong inhibitory effect on nitrogenase activity. However, no inhibitory effect on microbial respiration was detected.

Adenosine Triphosphate↗

PubMed2002

Use of a microbial sensor: a new approach to the measurement of inhibitory effects on the microbial activity of activated sludge.

This paper presents a new method for the measurement of inhibitory effects in wastewater treatment plants on the basis of a continuous measurement of the microbial respiration product (CO(2)). The microbial sensor developed for this purpose consists of a small conical fluidized bed reactor connected to a cylindrical chamber that comprises part of the sample recirculation system. Activated sludge microbes are immobilized on spherical (diameter=1-2 mm) reticulated sinter glass carriers. Pure oxygen is supplied via the cylindrical chamber in order to sustain a highly dense population of microbial mass. The mean hydraulic retention time in the microbial sensor ranges between 30 and 40 min, while temperature is maintained at 30 degrees C, and pH 6.4. Carbon dioxide in the off-gas, which reflects the microbial activity, is continuously analyzed by means of an infrared analyzer. Inhibition of microbial activity (toxicity) can be determined as the mean percent reduction in carbon dioxide concentration. Several substances were tested and proved toxic to the microbes. With this microbial sensor, early detection of toxic substances becomes feasible, preventing them from entering an activated sludge unit operation.

Journal Article↗

PubMed2005

Oxyleghemoglobin scavenges nitrogen monoxide and peroxynitrite: a possible role in functioning nodules?

It has been demonstrated that the NO* produced by nitric oxide synthase or by the reduction of nitrite by nitrate reductase plays an important role in plants' defense against microbial pathogens. The detection of nitrosyl Lb in nodules strongly suggests that NO* is also formed in functional nodules. Moreover, NO* may react with superoxide (which has been shown to be produced in nodules by various processes), leading to the formation of peroxynitrite. We have determined the second-order rate constants of the reactions of soybean oxyleghemoglobin with nitrogen monoxide and peroxynitrite. At pH 7.3 and 20 degrees C, the values are on the order of 10(8) and 10(4) M-1 s-1, respectively. In the presence of physiological amounts of CO2 (1.2 mM), the second-order rate constant of the reaction of oxyleghemoglobin peroxynitrite is even larger (10(5) M-1 s-1). The results presented here clearly show that oxyleghemoglobin is able to scavenge any NO* and peroxynitrite formed in functional nodules. This may help to stop NO* triggering a plant defense reaction.

Free Radical Scavengers↗

PubMed1976

The bacteriological diagnosis of pyogenic meningitis from cerebrospinal fluid dried on filter paper.

Cerebrospinal fluid from patients with pyogenic meningitis in two rural hospitals in Nigeria was dried on filter paper and sent by post for analysis in a reference laboratory. Microbial antigens were detected by counter-current immunoelectrophoresis in 78 of the 142 specimens (55%). This method of detecting antigens deserves further application for epidemiological and diagnostic work in developing countries.

Antigens, Bacterial↗

PubMed1996

Compatibility of propofol, fentanyl, and vecuronium mixtures designed for potential use in anesthesia and patient transport.

STUDY OBJECTIVE: To determine whether propofol emulsion, fentanyl, and vecuronium remain compatible and stable when mixed in clinically appropriate concentrations. DESIGN: Seven separate in vitro experiments. Two different propofol-fentanyl-vecuronium mixtures were formulated. Regular assays of propofol, fentanyl, and vecuronium were performed during a 90-minute infusion period and also during storage of one of the mixtures for 30 days at 4 degrees C, 22 degrees C, and 30 degrees C. Initial and storage pH were determined, and assays of the three drugs were performed when pH of the mixtures was varied between 1.4 and 12.7. Emulsion stability was assessed by measuring immediate and delayed alterations in droplet charge (zeta potential) and size. Finally, samples of the stored mixtures were incubated in culture medium for one week. SETTING: Teaching hospital and university laboratories. MEASUREMENTS AND MAIN RESULTS: Concentrations of the three drugs remained unchanged during infusion. During storage, concentrations of all three drugs were stable for two weeks at 4 degrees C or 22 degrees C, and for several days at 30 degrees C. Initial pH of the two mixtures was 5.1 and 5.3, and pH of the stored mixture increased slowly after 8 days. When the pH of mixtures was greater than or equal to 5.6, concentrations of fentanyl and vecuronium were unstable, but the concentration of propofol remained unchanged. Despite a reduction in zeta potential, immediate droplet size was essentially unchanged. No microbial growth was detected in stored mixtures. CONCLUSION: The propofol, fentanyl, and vecuronium mixtures studied were compatible and stable immediately after mixing. Appropriate in vitro compatibility testing is recommended before clinical evaluation of propofol-opioid or propofol-opioid-muscle relaxant mixtures.

Anesthesia↗

PubMed2006

Plant pathogens trick guard cells into opening the gates.

The stomata of plants regulate gas exchange and water transpiration in response to changing environmental conditions. New work reveals that stomata also have an important role in host defense. In this issue of Cell, Melotto et al. (2006) show that stomata close upon detection of potential microbial pathogens to prevent the infection of the leaf interior. Moreover, pathogenic bacteria have evolved strategies to suppress the closure of stomata.

Amino Acids↗

PubMed2006

Microbial activity in an acid resin deposit: biodegradation potential and ecotoxicology in an extremely acidic hydrocarbon contamination.

Acid resins are residues produced in a recycling process for used oils that was in use in the forties and fifties of the last century. The resin-like material is highly contaminated with mineral oil hydrocarbons, extremely acidic and co-contaminated with substituted and aromatic hydrocarbons, and heavy metals. To determine the potential for microbial biodegradation the acid resin deposit and its surroundings were screened for microbial activity by soil respiration measurements. No microbial activity was found in the core deposit. However, biodegradation of hydrocarbons was possible in zones with a lower degree of contamination surrounding the deposit. An extreme acidophilic microbial community was detected close to the core deposit. With a simple ecotoxicological approach it could be shown that the pure acid resin that formed the major part of the core deposit, was toxic to the indigenous microflora due to its extremely low pH of 0-1.

Biodegradation, Environmental↗

PubMed2006

Efficient T cell activation via a Toll-Interleukin 1 Receptor-independent pathway.

Here, we describe a previously unrecognized pathway for activation of antigen-specific adaptive immune responses that was independent of Toll-Interleukin 1 Receptor signaling and directed toward detection of antigens expressed by apoptotic cells. This pathway is represented within Flt-3 Ligand-derived dendritic cells (DCs) that represent immature lymphoid DCs, but not within GM-CSF-treated bone marrow-derived dendritic cells. Exposure of these DCs to apoptotic cells resulted in production of type I interferon and favored the development of cytotoxic T cell responses. The N-Ethyl-N-Nitrosourea-induced germline mutation 3d (Unc3b1(3d/3d)) abolished both MHC class I and II responses elicited by this pathway, whereas a null allele of Cd36 selectively abolished class II responses. We propose that this mode of adaptive immune activation evolved to permit the sensitive detection of intracellular microbial infections, particularly viral infections, which frequently induce apoptotic cell death, but may also be important in transplantation, autoimmunity, and vaccine development.

Animals↗

PubMed2005

[Emergent pathogens, international surveillance and international health regulations (2005)].

In order to address the vitality of the microbial world, to detect emerging infectious diseases, to determine their potential threat to public health, and to establish effective interventions, the World Health Organization (WHO) has developed and coordinates the Global Outbreak Alert and Response Network (GOARN) which connects several surveillance networks. Some of these networks are specific to epidemic-prone diseases, such as influenza, dengue, yellow fever or meningitis. Others were especially designed to track unusual events--such as the emergence of SARS--that are naturally-occurring, accidental, or deliberately created (biological weapons, bio-terrorism). Lastly, a special effort is being made at the international level to modernize the International Health Regulations, now obsolete, and to support all the countries in the reinforcement of their outbreak alert and response capacity.

Communicable Diseases, Emerging↗

PubMed2004

Expressing an antibacterial protein in bacteria for raising antibodies.

Magainins are small peptides with broad-spectrum activity against a range of plant and animal microbial pathogens. To detect magainin peptides in applications such as Western blot analysis and enzyme-linked immunosorbent assays, specific antibodies that recognize magainin peptides are required. The production of antibodies against small peptides injected into host animals poses problems with respect to eliciting an adequate immunogenic response due to the small size of the molecules. To increase the immunogenicity of a target peptide, it may be expressed as part of a larger fusion protein. However, expression of an antimicrobial peptide in bacteria may be cytotoxic to the host or subjected to degradation by host-derived peptidases. To overcome these potential problems, we fused the DNA coding sequence of a magainin gene analogue within the sequence of a bacterial thioredoxin gene. The subsequent gene fusion comprising a bacterial thioredoxin gene with a magainin coding sequence ligated at the active site of thioredoxin was successfully translated in a bacterial expression system. The fusion protein was non-toxic to the host bacteria. This represents a novel strategy to express antimicrobial peptides in a bacterial expression system. The fusion protein, purified by molecular size separation, was recovered in a soluble form following electroelution from polyacrylamide gels. Sufficient fusion protein was obtained for injection into rabbits and antibodies were obtained from rabbit sera that selectively recognized magainin peptides in Western blot analysis.

Amino Acid Sequence↗

PubMed2006

Eight-channel ultrasonic device for non-invasive quality evaluation in packed milk.

An eight-channel ultrasonic detecting device for microbiological quality evaluation of packed liquid foods is presented in this paper. This device makes possible a non-invasive detection of the microbial growth in liquid foods with no need to open the carton-based packages where they are contained. Thermal and humidity stabilization are required inside the measuring chamber. The changes in the liquid media produced by the microorganism growth induce variations in the ultrasonic propagation parameters giving a non-invasive evidence of the developing contamination. For that purpose, the amplitude and time of flight of an ultrasonic 800kHz tone burst travelling through an UHT milk pack are analysed. Inoculated and sterile packs were tested to evaluate the performance of this new non-invasive ultrasonic microbiological quality sensor.

Animals↗