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PubMed1986

Sensitivity of Branhamella catarrhalis to oral antibiotics.

B. catarrhalis is a potential pathogen in the upper and lower respiratory tract which has been implicated as a clinically important cause of chronic bronchitis and otitis media in children. Since the late 1970s the proportion of B. catarrhalis strains elaborating beta-lactamase seems to have significantly increased; some centres are now reporting prevalence rates as high as 76%. Such a dramatic increase in the number of beta-lactamase positive strains is of clinical importance when assessing the indirect pathogenic potential of B. catarrhalis and when selecting suitable antimicrobial therapy. Early studies showed that B. catarrhalis was sensitive to penicillin V with a MIC90 of 1.2 mg/L while, more recently, MIC90 values of 2.0 mg/L have been noted. Ampicillin and, perhaps surprisingly, cefaclor are also inactivated by some beta-lactamase-producing strains of B. catarrhalis. A majority of strains of B. catarrhalis is susceptible to erythromycin (MIC90 0.15 to 0.5 mg/L) and tetracyclines (especially doxycycline, MIC90 0.25 to to 0.5 mg/L). Co-trimoxazole also seems to be effective against most isolates of B. catarrhalis whereas trimethoprim alone is relatively ineffective.

Administration, Oral↗
PubMed1984

Natural history of intestinal parasites in asymptomatic adults.

The need to treat asymptomatic adults who have intestinal parasites should be based on considerations of potential pathogenicity and transmission risk, but such data are sparse in general and unavailable for countries such as the United States, where reinfection is rare. Opinions of North American physicians about the natural history and treatment of 12 parasites detectable by stool examination were assessed using the Delphi technique. In response to the first questionnaire, majority agreement on pathogenic potential was achieved for only 3 of 12 parasites. When the more expert group was queried a second time, majority agreement was achieved for 8 of 12 parasites. Nevertheless, the predicted risk of subsequent disease still varied widely, from 1:10 to 1:1,000 for most parasites, and was unrelated to the perceived need for treatment. Almost all respondents thought asymptomatic adults with any intestinal parasites should always be treated. Transmission risk was judged to be low and was generally appropriate to the life cycle of the parasite.

Adult↗
PubMed1981

Laboratory diagnosis of animal mycoplasma infections.

Laboratory diagnosis of animal mycoplasma infections is generally based on isolation of the mycoplasmas from the diseased tissues, followed by biochemical and serological identification of the isolates. However, the presence of serum antibodies and the demonstration of circulating antigen or antigen in infected lung tissue has also proved invaluable in the diagnosis of contagious bovine pleuropneumonia. The isolation of a particular mycoplasma from a diseased tissue does not necessarily imply a causal relationship. It is important to know the pathogenicity potential of the mycoplasma in question, the number of mycoplasmas present, the presence of any other potentially pathogenic microorganisms and any other relevant information before the role of the mycoplasma can be assessed and a diagnosis of mycoplasma infection given.

Animals↗
PubMed1997

[Changes in the microbial picture during the production of poultry salami].

Changes in microbiological parameters during the production of fine poultry salami was monitored in a private poultry-processing plant in Kosice within a period of six months. This product consists of meat paste or mechanically deboned poultry meat (MDPM), which is produced with the help of a Protecon MPB 30 E deboning machine, pork trimmings, water (in the form of crushed ice), salt, spices, and garlic paste. The main raw food material (hand-boned meat and skin from poultry carcasses intended for mechanical deboning), MDPM immediately after production, salted MDPM after its 24-hour-storage and ripening in the chiller, pork trimmings added to MDPM at an amount of 25%, prepared salami emulsion, and the final product (fine poultry salami) were examined for the presence of pathogenic and potentially pathogenic microorganisms. The total plate count, the counts of indicatory microorganisms (Coliforms and Enterococci), Staphylococci, psychrotrophic, proteolytic and lipolytic bacteria were also determined according to the Slovak government regulations. The results of the quantitative microbiological examination are shown in Figs. 1 and 2. It follows from them that the microbial load of poultry skin is considerably higher than that of hand-boned meat. During the deboning process an increase in all microbial parameters (on average by 1-3 radices) was noticed as compared with the raw food material (defrosted poultry carcasses before the mechanical deboning). MDPM contained 10(4)-10(7) CFU/g; the count of coliforms ranged between 10(3) and 10(6)/g; the count of proteolytic and lipolytic bacteria between 10(4) and 10(6)/g; the count of Staphylococci and Enterococci between 10(2) and 10(4)/g. Staphylococcus aureus was discovered in about 50% samples of MDPM in an average concentration of 10(2)/g. In addition to the groups of bacteria listed above, a wide range of potentially pathogenic microorganisms belonging to the family Enterobacteriaceae, especially those of the genus Proteus, Escherichia coli, Citrobacter and Providencia, was also found in MDPM. In four cases Salmonella enteritidis was also detected in the samples of both the skin of chicken carcasses and the MDPM. The nitrate salting mixture added at a concentration of 2% did not significantly reduce the counts of bacteria present in the MDPM. The prepared salami emulsion was very high in all groups of microorganisms, which was also caused by the addition of pork trimmings. This component seems to be a very important source of microbial contamination, showing the following average bacterial counts: total plate count 4.8 x 10(6)/g, the count of psychrotrophic bacteria 1.0 x 10(6)/g, the count of coliforms 7.0 x 10(5)/g, the count of Enterococci 9.2 x 10(3)/g, the count of Staphylococci 3.0 x 10(4)/g, the count of proteolytic microorganisms 2.7 x 10(5)/g, and the count of lipolytic microorganisms 4.2 x 10(5)/g. However, heat treatment of the final product reliably and almost completely devitalized all the bacteria found in the salami emulsion before heat processing. No pathogenic or potentially pathogenic bacteria were detected in any sample of fine poultry salami. Quite a high number of bacteria in the salami emulsion was reduced by heat treatment to a final average value of 10(2)/g.

Animals↗
PubMedDate not supplied

Ecology of cycloheximide-resistant fungi in field soils receiving raw city wastewater or normal irrigation water.

The effect of raw city wastewater irrigation on biodiversity and population densities of a cycloheximide-resistant (CH) fungal community was studied in 13 field soils receiving either raw city wastewater or normal irrigation, and in raw city wastewater in the Nablus area, using the hair baiting technique (HBT) and a surface soil dilution plating (SSDP) technique. Three of these fields [one had been receiving raw city wastewater for more than ten years and was designated a heavily polluted field, and the other 2 were cultivated for the first time and were either irrigated with raw city wastewater (newly polluted field) or normal irrigation water (nonpolluted)], were sampled 4-7 times over a 9-month period. The other ten fields, which had been under raw city wastewater irrigation for more than 10 years, were sampled only once. Fifty-seven CH-resistant species belonging to 18 genera were recovered, of which 49 species were recovered from soil habitats and 28 species from raw city wastewater. The HBT had shown to be more efficient in the isolation of pathogenic and potentially pathogenic fungi including dermatophytes. A higher percentage of this group of fungi was recovered from the three main field soils studied using HBT (70% of all isolates), than the SSDP (35.5%); no dermatophytes were recovered by the SSDP method. Two dermatophytes (Microsporum gypseum, and Trichophyton ajelloi), and five more fungi (Arthroderma cuniculi, A. curreyi, Chrysosporium keratinophilum, C. tropicum, C. pannorum), were recovered from these habitats. Wastewater irrigation seemed to have affected the fungal population densities, with the highest population densities being found in the heavily polluted field soil, while lower population densities were found in the nonpolluted field soil. Increases in organic matter were also observed as a result of sewage effluent irrigation. However, basic similarities in the biodiversity of CH-resistant fungal communities existed in nonpolluted and polluted field soils, and raw city wastewater. Comparable numbers of fungal species were recovered from the three main field soils. The species most commonly found in those habitats included: Alternaria alternata, Aspergillus candidus, Geotrichum candidum, and Paecilomyces lilacinus. Field soils receiving either raw city wastewater or normal irrigation water, were found to be rich in pathogenic and potentially pathogenic CH-resistant fungi, including dermatophytes, with raw city wastewater yielding the highest percentage (81%), followed by the newly wastewater irrigated field (77.7%), the nonpolluted field (67%), and the heavily polluted field (63.4%) Hygienic measures should therefore be taken to control the spread of these fungi in the environment of human communities, and to avoid mycotic infections among farmers.

Agriculture↗
PubMed2004

Isolation of gram-negative bacteria from cockroaches trapped from urban environment.

Three different areas--hospital, food-handling establishments and human dwellings, were surveyed for pathogenic gram-negative bacteria carried on the cuticles of cockroaches. Fifty species of bacteria were identified from all cockroaches. Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii and Enterobacter cloacae were the most frequently found. Pathogenic and potentially pathogenic bacteria represented 58% of all bacteria identified. The numbers of pathogenic and potentially pathogenic bacteria were similar in hospital areas and food-handling establishments, while, human dwellings possessed a poorer bacterial flora. E. coli, K. pneumoniae and E. cloacae were dominant species in hospital areas, while in food-handling establishments and human dwellings, E. coli, K. pneumoniae and C. freundii predominated. Therefore, cockroaches can play a role in bacterial transmission, due to the bacteria carried on their cuticles.

Animals↗
PubMed1975

Comparative in vitro antifungal activity of amphotericin B and amphotericin B methyl ester.

The in vitro antifungal activity of amphotericin B methyl ester (AME), a water-soluble derivative of amphotericin B, was compared to that of the parent compound against a variety of pathogenic and potentially pathogenic fungi. AME has a significant antifungal activity, but the activity of AME was slightly lower than that of amphotericin B. Among the yeast-like organisms, only the yeast cells of Sporothrix schenckii were more resistant than others to both antibiotics, with a minimal fungicidal concentration of 5 to 10 mug/ml. The yeast cells of other fungi were killed at concentrations of 1 mug or less of either antibiotic per ml. The filamentous forms of S. schenckii and Oidiodendron kalrai were more resistant than the filamentous forms of other dimorphic fungi to both drugs. The minimal fungicidal concentration for S. schenckii was 10 mug/ml and for O. kalrai, 50 mug/ml. The dermatophytes, phycomycetes, and dematacious and other potentially pathogenic fungi were inhibited fairly well by both drugs, but up to 50 mug/ml was required for fungicidal action. The water solubility and wide spectrum of antifungal activity of AME warrant evaluation of its chemotherapeutic activity against experimental fungal infections.

Amphotericin B↗
PubMed2005

Relevant aspects of Arcobacter spp. as potential foodborne pathogen.

Arcobacter species are Gram-negative spiral-shaped organisms belonging to the family Campylobacteraceae that can grow microaerobically or aerobically. The Arcobacter organisms also have the ability to grow at 15 degrees C, which is a distinctive feature that differentiates Arcobacter species from Campylobacter species. Cultural detection of Arcobacter is generally performed by an enrichment step and takes 4 to 5 days. In the last few years, several studies comparing different culture-based protocols have been published. Furthermore, DNA-based assays have also been established for rapid and specific identification of Arcobacter spp. Recent evidence suggests that Arcobacter, especially A. Butzleri, may be involved in human enteric diseases. Moreover, A. butzleri has also occasionally been found in cases of human extraintestinal diseases. However, up to now, little is known about the mechanisms of pathogenicity or potential virulence factors of Arcobacter spp. There is evidence that livestock animals may be a significant reservoir of Arcobacter spp. and over the last few years, the presence of these organisms in raw meat products as well as in surface and ground water has received increasing attention. In view of control measures to be used to prevent or to eliminate the hazard of Arcobacter spp. in food, several treatments have been evaluated for their effectiveness. While the role of Arcobacter spp. in human disease awaits further evaluation, a precautionary approach is advisable. Measures aimed at reduction or eradication of Arcobacter from the human food chain should be encouraged. With this article, we review the recent literature on this organism with a special emphasis on the information relevant to food safety.

Animals↗
PubMed1982

The role of wild animals in the ecology of dermatophytes and related fungi.

The problems associated with infections by dermatophytes and related fungi are discussed. Published and unpublished surveys of 1 481 wild animals of the orders Carnivora, Ungulata, Lagomorpha, Rodentia, Insectivora and Chiroptera and of 29 birds proved to be positive for fungi which were classified as potentially pathogenic zoophilic, potentially pathogenic geophilic and normally non-pathogenic geophilic. Trichophyton mentagrophytes var. mentagrophytes was isolated from 11% of rodents; the fungus was also isolated from Insectivora, the hare and the ibex. T. mentagrophytes var. erinacei was reported in the hedgehog. Microsporum canis was reported in rodents from anthropogenic areas. M. gypseum was reported in Ungulata, Lagomorpha and Rodentia; other geophilic fungi were found in all the orders investigated, with the exception of Chiroptera which proved to be constantly negative. The relationship between the presence of animals and the "animalization" of the environment, and the consequent presence of geophilic fungi is discussed. It is concluded that wild animals may play a role as carriers of dermatophytes and related fungi, may create environmental conditions favourable to their growth and may help to monitor the presence of a fungus in a given area.

Animal Population Groups↗
PubMed2001

Does bathing newborns remove potentially harmful pathogens from the skin?

BACKGROUND: Newborn infants are routinely bathed after birth partly to reduce the possibility of transmitting potential pathogens to others. The extent to which a mild soap reduces the quantity and type of microbes found on the skin through normal colonization has not been reported. The objective of the study was to compare colonization rates between infants bathed in soap and water and infants bathed in plain water. METHOD: One hundred and forty infants were randomly assigned to one group bathed in a mild pH neutral soap and water or to another group bathed in water alone. Microbiology swabs were taken on three occasions (before the first bath, 1 hour after the bath, and 24 hours after birth) from two sites (anterior fontanelle and umbilical area). RESULTS: No difference occurred between groups on type or quantity of organisms found at each time period. Skin colonization is a function of time, and the quantity of organisms identified increased over time (Friedman A 2 = 111.379, df = 5, p < 0.001). CONCLUSIONS: Bathing with mild soap as opposed to bathing in water alone has minimal effect on skin bacterial colonization. Skin colonization increased over time. The findings did not support the efficacy of bathing with soap and water to reduce skin colonization of bacterial pathogens. Although the incidence of potential pathogens colonizing the skin during the first day of life is low and unlikely to pose a risk to healthy newborns, health care professionals may wish to wear gloves until the infant has been bathed.

Bacterial Infections↗
PubMed1979

Killer phenomenon in pathogenic yeast.

Potentially pathogenic yeast strains from four genera, Candida, Cryptococcus, Torulopsis, and Trichosporon, were examined for killer activity and sensitivity using Saccharomyces and Torulopsis strains of known killer status. Tests were performed by using a streak method and by concentration of culture fluid by lyophilization. Of 236 strains examined, killers were found with low prevalence among Torulopsis and Cryptococcus strains; Candida and Trichosporon isolates showed no killing activity. Different specificities of killing activity were observed among strains of a single species. Sensitive strains were found with varying frequencies in all genera but Trichosporon.

Candida↗
PubMed2002

Dynamics of nasopharyngeal colonization by potential respiratory pathogens.

Studies have shown that colonization of the nasopharynx by potential respiratory pathogens Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis is established early in childhood, although rates vary greatly according to locality, sampling frequency, individual and social factors. Factors influencing colonization and elimination are not as yet fully understood, but adhesion to mucosal receptors and immune responses are implicated in addition to bacterial properties and colonization resistance dynamics. Colonization in children and adults has been intensively studied in various localities. Potential pathogens are more likely to colonize the nasopharynx of children prone to recurrent otitis media, where impaired local immunity and repeated exposure to respiratory pathogens are additional risk factors. Adults with chronic respiratory tract disease also have higher carriage rates. The factors contributing to increased risk of carriage of potential respiratory pathogens, as well as to clinical infection and antimicrobial resistance, are summarized in this review.

Animals↗
PubMed1990

The 96-kilodalton antigen as an integral membrane protein in pathogenic Entamoeba histolytica: potential differences in pathogenic and nonpathogenic isolates.

A surface antigen (EH-96) of Entamoeba histolytica was demonstrated to be a plasma membrane antigen by immunoprecipitation of metabolically 35S-labeled antigen from live trophozoites, Triton X-114 detergent extracts, and plasma membrane-enriched fractions prepared by concanavalin A membrane stabilization and differential centrifugation. In addition, the antigen was localized to the plasma membrane by electron microscopy with colloidal gold. Antigen from E. histolytica strains immunoprecipitated with specific immunoglobulin M (IgM) or IgG2b monoclonal antibody was identical by one-dimensional peptide mapping with N-chlorosuccinimide. Additionally, antigen from different axenically cultivated amebae was demonstrated to be identical by N-chlorosuccinimide peptide mapping, as were peptide maps of IgG and IgM monoclonal antibody-purified antigen. The 96-kilodalton (kDa) surface antigen was identified on four axenically cultivated pathogenic isolates and on three polyxenically cultivated pathogenic isolates (zymodeme II) of E. histolytica but was absent or present in lesser quantity on six nonpathogenic polyxenically cultivated isolates. The 96-kDa antigen was detected in liver abscess fluid from four patients with amebic abscesses by enzyme-linked immunosorbent assay (ELISA) and immunoprecipitation. Two-dimensional gel electrophoresis profiles of the 96-kDa antigen purified from abscess material or from polyxenically cultivated trophozoites demonstrated that the antigens were related to the 96-kDa antigen found in axenically cultivated organisms.

Animals↗
PubMed1997

Effect of preventive administration of a nonpathogenic Escherichia coli strain on the colonization of the intestine with microbial pathogens in newborn infants.

In a randomized, double-blind study, 27 healthy newborn infants were colonized with the nonpathogenic Escherichia coli strain Nissle 1917 (E. coli DSM 6601, Mutaflor) during the first 5 days of life by daily oral inoculation of 1 ml of a suspension with 10(8) living cells. A second group of 27 newborns, used as controls, received a placebo suspension (1 ml of phosphate-buffered saline) instead. Stool samples were taken on days 1, 2, 3, 5, and 21, and 6 months after birth. All samples were examined for the presence of the nonpathogenic E. coli strain and of pathogenic and potentially pathogenic microorganisms. The administered E: coli strain was detected in the stools of the colonized newborns from day 2 and remained present throughout the study in more than 90% of these infants. Colonization with true and potential bacterial pathogens was significantly reduced in infants receiving E. coli strain Nissle 1917 compared to the placebo group--both with respect to numbers of pathogens and to the spectrum of species.

Acinetobacter↗
PubMed2006

Colonisation on the tongue surface by respiratory pathogens in residents of a nursing home--a pilot study.

OBJECTIVE: The morbidity and mortality of the dependent elderly that result from aspiration pneumonia have been recognised as a major geriatric health problem. The tongue has an extremely large surface area and due to its papillary structure can retain considerable quantities of food, and thus can support and harbour a large bacterial population. The purpose of this study was to gain more information on the microflora of the tongue surface and to assess the existence of oral infectious pathogens potentially causing respiratory disease in nursing home residents. SUBJECTS AND METHODS: The tongue bacterial flora of 69 nursing home residents were examined to identify microorganisms by the culture method. RESULTS: Thirteen species of microorganisms were detected from the tongue in this study. In 41 of 69 subjects (59%), potential respiratory pathogens, had colonised the tongue surface. CONCLUSION: The results of the present study revealed that bacteria that commonly cause respiratory infection colonised the tongue of nursing home residents, suggesting that it may function as a reservoir of potential respiratory pathogens to facilitate colonisation on the oropharynx.

Aged↗
PubMed1984

Bacteria associated with crabs from cold waters with emphasis on the occurrence of potential human pathogens.

A diverse array of bacterial species, including several potential human pathogens, was isolated from edible crabs collected in cold waters. Crabs collected near Kodiak Island, Alaska, contained higher levels of bacteria than crabs collected away from regions of human habitation. The bacteria associated with the crabs collected near Kodiak included Yersinia enterocolitica, Klebsiella pneumoniae, and coagulase-negative Staphylococcus species; the pathogenicity of these isolates was demonstrated in mice. Although coliforms were not found, the bacterial species associated with the tissues of crabs collected near Kodiak indicate possible fecal contamination that may have occurred through contact with sewage. Compared with surrounding waters and sediments, the crab tissues contained much higher proportions of gram-positive cocci. As revealed by indirect plate counts and direct scanning electron microscopic observations, muscle and hemolymph tissues contained much lower levels of bacteria than shell and gill tissues. After the death of a crab, however, the numbers of bacteria associated with hemolymph and muscle tissues increased significantly. Microcosm studies showed that certain bacterial populations, e.g., Vibrio cholerae, can be bioaccumulated in crab gill tissues. The results of this study indicate the need for careful review of waste disposal practices where edible crabs may be contaminated with microorganisms that are potential human pathogens and the need for surveillance of shellfish for pathogenic microorganisms that naturally occur in marine ecosystems.

Alaska↗
PubMed1996

Taxonomy, biology, and periodontal aspects of Fusobacterium nucleatum.

The pathogenic potential of Fusobacterium nucleatum and its significance in the development of periodontal diseases, as well as in infections in other organs, have gained new interest for several reasons. First, this bacterium has the potential to be pathogenic because of its number and frequency in periodontal lesions, its production of tissue irritants, its synergism with other bacteria in mixed infections, and its ability to form aggregates with other suspected pathogens in periodontal disease and thus act as a bridge between early and late colonizers on the tooth surface. Second, of the microbial species that are statistically associated with periodontal disease, F. nucleatum is the most common in clinical infections of other body sites. Third, during the past few years, new techniques have made it possible to obtain more information about F. nucleatum on the genetic level, thereby also gaining better knowledge of the structure and functions of the outer membrane proteins (OMPs). OMPs are of great interest with respect to coaggregation, cell nutrition, and antibiotic susceptibility. This review covers what is known to date about F. nucleatum in general, such as taxonomy and biology, with special emphasis on its pathogenic potential. Its possible relationship to other periodontal bacteria in the development of periodontal diseases and the possible roles played by OMPs are considered.

Amino Acid Sequence↗
PubMed1980

The non-value of preoperative and intraoperative cultures in predicting the bacteriology of subsequent wound infection in patients undergoing major head and neck cancer surgery.

A prospective study of patients undergoing major head and neck cancer surgery was undertaken to define the value of preoperative and intraoperative cultures in identifying the patient at "high risk" of wound infection and in predicting the bacteriology of wound infection. One or two days before surgery, the skin of the operative site on the neck, the oropharynx and anterior nares were swabbed. an intraoperative wound culture was obtained after the pharyngeal defect was closed and the wound irrigated with water. All cultures were processed for aerobes in the Anaerobic Bacteriology Research Laboratory at Wadsworth Hospital Center. Wound infections developed in 10 of 31 patients who received cefazolin prophylactically and 21 of 25 patients who received no perioperative antibiotics. Fifty-five percent of infected patients and 68% of noninfected patients demonstrated potential pathogens preoperatively. A potential pathogen isolated preoperatively or intraoperatively was subsequently recovered from 35% of infected wounds. The majority of infected wound cultures grew one or more additional pathogens. A poor correlation was also noted between preoperative nasal Staphylococcus aureus isolation and subsequent recovery from wound infections. We conclude that preoperative and intraoperative aerobic wound cultures are not predictive of the "high risk" patient or of the bacteriology of subsequent wound infection in major head and neck cancer surgery.

Bacteriological Techniques↗