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PubMed2003

[Clinical significance of studies of microorganisms of the intestinal mucosa by culture biochemical methods and mass fragmentography].

This research is a continuation of the series of studies of the parietal microbiota of the bowel tissue samplings by the gas chromatography and mass spectrometry (GCMS) method [G.A. Ossipov et al.//Journal of the Society of Russian Gastroenterologists, 2001, 1:54-69]. The purpose was to study a number of new microorganisms in view of new data on the composition of their fatty acids (FA) and aldehydes; to confirm the presence of a number of bacteria, fungi and aerobic actinomycetes revealed earlier by FA markers in the composition of the bowel parietal microbiota by their isolation in a pure culture; to amend the estimation of the clinical value of changes in the composition of the human bowel parietal microflora in case of irritable bowel syndrome (IBS) and antibiotics-associated diarrhea (AAD). We examined 31 patients with IBS with predominating diarrhea, 18 patients with AAD and 3 volunteers (a control group). We studied the blood samples, tissue samplings of the mucous coat of the jejunum, ileum and colon and composition of healthy people's feces. The GCMS method was applied. Morphology of defined strains was controlled by methods of light and scanning electron microscopy. We found a substantial portion of eubacteria among the bowel microorganisms and specific changes of their species in case of IBS and AAD. Taking into account their physiological and biochemical activity, when regulating their concentration one can expect at least the same effect as when regulating the number of bifidobacteria and lactobacilli in treatment of intestinal pathologies and other diseases related to bowel dysbacteriosis. The analysis of the feces microbiota using the GCMS method by FA of parietal microorganisms provides reliable data on their number both in feces and in tissue samplings. We found a substantial portion of eubacteria among other bowel microorganisms (27% in the jejunum and 16% in the colon) and specific changes of their species in case of IBS and AAD. The concentration of streptomycetes, rhodococci and other members of the Actinomycetales order becomes dozens times more and/or reduces in pathological states. The tenfold concentration of markers of lactobacilli and bifidobacteria in some diseases stimulates the differentiated application of widespread probiotics based on these bacteria.

Bacteria↗
PubMed2003

[Airborne microorganisms in a rearing henhouse for layers during vaccination].

Airborne microorganisms are proved regularly in livestock houses as a part of stable dust and its amount depends on housing conditions, the flow of air and the movement of material. Health of animals and farmers can be influenced in a negative way by these bioaerosols. In a rearing house for layers concentrations of various groups of airborne microorganisms were measured during vaccination by a veterinary and his three assistants. During the vaccination activities the concentrations of some airborne microorganisms increased by a factor of ten to the following medians of colony forming units (cfu) on used selective agars (cfu/m3): 10(3) on MacConkey (36 degrees C), 10(3) on Dichloran-Glycerol (25 degrees C), 10(7) on Tryptone Soy (CaSo, 36 degrees C), 10(3) on Salmonella-Shigella (36 degrees C), 10(2) yeasts on Sabouraud (36 degrees C), and 10(2) on Campylobacter (36 degrees C). Thermophilic fungi were only grown on some of the used Maltextract agar dishes (45 degrees C) in concentrations near of the limit of detection. Some aerial samples were analysed for Chlamydia. Chlamydophila psittaci was not detected. Concentrations of airborne microorganisms in livestock houses depends not only on housing conditions but also on specific work procedures of farmers or on the activity of the animals.

Air Microbiology↗
PubMed1992

Ultrastructure of symbiont-like microorganisms associated with the sperm of ixodid ticks.

The endospermatophores found in the seminal receptacles of three species of Ixodid ticks: Hyalomma marginatum, H. dromedarii and Amblyomma hebraeum were examined. The seminal receptacles showed the presence of symbiont-like microorganisms in association with the sperm cells. These yeast-like microorganisms represent extracellular symbionts, produced by the male and introduced in the genital system of the female through copulation. The symbionts frequently occur freely in large agglomerations surrounded by a large amount of alpha-glycogen rosettes. They do not alter their shape nor do they attach to the sperm cells. Another kind of Rickettsia-like microorganisms is present in tissues of some tick organs. This could be a form of disease agents or naturally occurring microorganisms in the tissue of tick organs.

Animals↗
PubMed2004

[Effects of long-term fertilization on soil microorganism and its role in adjusting and controlling soil fertility].

To clarify the relationships between soil microorganisms and soil fertility under the condition of long-term fertilization, a 12-year fertilization experiment was installed on a fluvo-aquic soil, and the amount of soil microorganisms and the content of soil nutrients were determined and analyzed. The results showed that chemical fertilizers combined with organic manure could significantly improve soil fertility and increase the amount of soil microorganisms. Organic manure was obviously superior to corn straw in improving soil fertility. The correlation between soil microorganisms and soil fertility was significant. A positive correlation was found between the amount of bacteria and azotobacteria and the contents of organic matter, total N, alkalified N, total P and available P. The relationship between the amount of fungi and actinomycetes and the content of soil nutrients was not obvious.

Actinobacteria↗
PubMed2004

[Function and application of soil microorganisms in forest ecosystem].

Soil microorganism is an important part of forest ecosystem, and plays an important role in sustainable development of forestry. In this paper, we summarized the main functions of soil microorganisms in forest sustainable development from the aspects of 1) the role of soil microorganism and microbiomass; 2) the function of mycorrhizal fungi; 3) the impact of pathogen; and 4) the effect of PGPR. Finally, we also discussed the research trends of forest soil microorganism and its application. Some study areas which should be further studied were also proposed.

Azospirillum↗
PubMed2005

[Affecting factors of soil microorganism and root respiration].

Soil respiration is an important part of the carbon cycle in terrestrial ecosystems, and its contribution to the global carbon budget has been the focus of wide concern. Researches on the affecting factors of soil microorganism and root respiration, the main components of soil respiration, contribute to the understanding of the role of soil respiration on global carbon cycle, and to the accurate evaluation of global carbon budget. This paper reviewed the direct and indirect affecting factors of soil microorganism and root respiration, including climate factors, soil properties, vegetation and litterfall, air CO2 concentration, and human activities. These affecting factors were interactive, and their contributions to soil microorganism and root respiration varied in temporal and spatial scales. The study on natural and anthropogenic factors of soil microorganism and root respiration was emphasized, and some related research tasks in the future were also proposed.

Bacteria↗
PubMed2005

Colonization of venous leg ulcers by microorganisms.

The aim of the study was to identify the microorganisms that most commonly colonize leg ulcers. The study included 70 patients of both sexes, aged 31-85 years. There were 49 (70%) female and 21 (30%) male patients, mean age 69.16 and 61.62 years, respectively. Nineteen different types of microorganisms were isolated in study patients: one in 18, two in 38, and three pathogens in 13 patients. Only one of study patients had four microorganisms isolated at the time. The most common microorganisms were Pseudomonas aeruginosa found in 25 and Streptococcus aureus in 19 patients.

Adult↗
PubMed2006

Variation of microorganism concentrations in urban stormwater runoff with land use and seasons.

Stormwater runoff samples were collected from outfalls draining small municipal separate storm sewer systems. The samples were collected from three different land use areas based on local designation (high-density residential, low-density residential and landscaped commercial). The concentrations of microorganisms in the stormwater runoff were found to be similar in magnitude to, but less variable than, those reported in the stormwater National Pollutant Discharge Elimination System (NPDES) database. Microorganism concentrations from high-density residential areas were higher than those associated with low-density residential and landscaped commercial areas. Since the outfalls were free of sanitary wastewater cross-connections, the major sources of microorganisms to the stormwater runoff were most likely from the feces of domestic animals and wildlife. Concentrations of microorganisms were significantly affected by the season during which the samples were collected. The lowest concentrations were observed during winter except for Staphylococcus aureus. The Pearson correlation coefficients among different indicators showed weak linear relationships and the relationships were statistically significant. However, the relationships between indicators and pathogens were poorly correlated and were not statistically significant, suggesting the use of indicators as evidence of the presence of pathogens is not appropriate. Further, the correlation between the concentration of the traditionally monitored indicators (total coliforms and fecal coliforms) and the suggested substitutes (enterococci and E. coli) is weak, but statistically significant, suggesting that historical time series will be only a qualitative indicator of impaired waters under the revised criteria for recreational water quality by the US EPA.

Bacteria↗
PubMedDate not supplied

[Hormones and hormone-like substances of microorganisms: a review].

Data from the literature on the ability of microorganisms to form plant hormones have been reviewed. The substances covered include abscisic acid, ethylene and other compounds with phytohormone-like properties (brassinosteroids, oligosaccharines) and analogues of animal neurotransmitters (biogenic amines). Pathways whereby the substances are metabolized and their effects on the development and activity (physiological and biochemical) of the microorganisms are considered. The role of phytohormones and hormone-like substances in the formation of association (microorganism-host) interactions are analyzed. The potential utilities of microorganisms producing hormones and hormone-like substances are discussed.

Animals↗
PubMedDate not supplied

The persistence of microorganisms on impression materials following disinfection.

Following in vitro inoculation with C albicans or P aeruginosa, three impression materials--polysulfide rubber, irreversible hydrocolloid, and poly(vinyl siloxane)--were disinfected with either 0.1% or 0.02% chlorhexidine gluconate and a quantitative assessment of the microorganisms was made. Very few microorganisms were retained on the poly(vinyl siloxane) material immediately after microbial inoculation. The numbers of microorganisms on polysulfide impression materials diminished rapidly with time even without disinfection, and a 30-minute disinfection procedure resulted in total microbe elimination. With irreversible hydrocolloid, microorganisms persisted and disinfection procedures were considerably less effective. When the disinfection efficacy of three commercially available agents was compared using irreversible hydrocolloid impression material, chlorhexidine gluconate (0.2%) was found to be less effective than either glutaraldehyde (2%) or sodium hypochlorite (0.0125%); the latter two agents were comparable in their antimicrobial effect. Thus, a simple disinfection regime of 30 minutes with commonly available disinfectants may be effective in eliminating cross-contamination from impression materials.

Anti-Infective Agents, Local↗
PubMedDate not supplied

Serum antibody levels to oral microorganisms in children and young adults with relation to the severity of gingival disease.

The purpose of this study was to describe and compare the IgG and IgM serum antibody levels to 10 microorganisms involved in periodontal diseases in children and young adults with no systemic disease, but with either minimal/none or severe gingival inflammation. Blood samples from 15 children and 14 young adults were collected. Seven children and nine adults had minimal or no gingival inflammation; the rest had severe gingivitis. Kruskal-Wallis H analysis indicated significant differences among the age groups in the IgM values for all microorganisms and for most organisms in the IgG values. The contrast coefficient matrix values between children and young adults were significant for all the microorganisms for the IgM values and for most of the organisms for the IgG values when the severity of the disease was not taken into consideration. However, when the severity of the disease was also considered, the contrast coefficient matrix values for most of the microorganisms were not significant for both the IgG and IgM values. Age had a more significant influence on the serum antibody levels than the severity of the disease, mostly in the IgM values.

Adult↗
PubMed1989

[The etiology of suppurative-inflammatory diseases caused by opportunistic microorganisms at the noninfectious disease clinic].

5,853 strains of opportunistic microorganisms have been isolated from hospitalized patients at a polyclinic. The following microorganisms have been found to cause purulent inflammatory diseases most frequently: Escherichia coli (21.6%), Staphylococcus epidermidis (15.93%), Staphylococcus aureus (14.54%), microorganisms of the genus Klebsiella (11.86%), Pseudomonas aeruginosa (7.91%) and microorganisms of the genus Proteus (7.5%). In cases of mixed infections Gram-negative bacteria prevail. The analysis of microbial species contained in the pathological excreta of patients in different departments has shown the prevalence of staphylococci in general surgery patients, E. coli in peritonitis and gynecological diseases, P. aeruginosa in patients with burns, Klebsiella, Proteus, E. coli, P. aeruginosa in patients with multiple traumatic lesions.

Bacterial Infections↗
PubMed1989

[Detection of group characteristics and contamination with microorganisms].

Evidence of group properties in traces and residues of human origin may be very difficult; very frequently in the same individual controversial results are obtained in different tissues but also in the same samples during repeated examinations. This was revealed by examinations of reliets from prehistorical findings as well as in remains of Czech historical personalities and contemporary important forensic cases, using different methods of detection, incl. the absorption elution test. The author discusses the condition of investigated residues and traces, the degree of decomposition of tissues due to the possible action of microorganisms with regard to assessment of group properties. The investigation revealed that in addition to the anticipated action of some microorganisms contaminating examined tissues, different transformation of group properties of the sample, and panaglutinability or disintegration of the entire ABO system, a possible effect of the organism's own serological activity of microorganisms on results must be also taken into account. Examination of different tissues of the individual, and if the results are controversial, examination of group properties of cultivated microorganisms makes it possible to eliminate to a certain extent the artificial component of results and makes the conclusions more accurate and helps to explain the interpretation of results.

Bacteria↗
PubMedDate not supplied

[Distribution of microorganisms lysing Pseudomonas aeruginosa in reservoirs and soil].

Various natural habitats were found to contain microorganisms producing lytic spots around their own colonies when grown on a lawn of viable Pseudomonas aeruginosa cells at 29 and 45 degrees C. The incidence of such microorganisms in water and soil was studied in quantitative terms. Contaminated waters with predominating Gram-negative heterotrophs and a high number of pseudomonades were shown to be an optimal source for the isolation of microorganisms causing the lysis of P. aeruginosa growing at 29 degrees C. Microorganisms responsible for the lysis of P. aeruginosa at 45 degrees C are abundant in the soil of mixed and foliage forests.

Bacteriolysis↗
PubMedDate not supplied

[Filing of microorganism strains for patent claims in the Soviet Union].

The modern state of depositing microorganisms with regard to patent procedure is considered. The main stages of depositing are described. Two questions of paramount importance for depositors are examined, i.e. what kind of microorganisms should not be deposited with regard to patent procedure, who and on what terms can get samples of deposited microorganisms from the collection. A number of recommendations for researchers potential depositors of microorganisms, are given.

Microbiology↗
PubMed1985

Should antimicrobial prophylaxis in colorectal surgery include agents effective against both anaerobic and aerobic microorganisms? A double-blind, multicenter study. The Norwegian Study Group for Colorectal Surgery.

It is now well demonstrated that a mixed flora of aerobic and anaerobic microorganisms will be found in wound abscesses and peritonitis after bowel surgery. An impressive reduction in infectious complications caused by anaerobic microorganisms can be achieved with nitroimidazole prophylaxis, but considerable uncertainty about the role of agents active against aerobic microorganisms in such prophylaxis still exists. We have earlier reported that a single dose of tinidazole and doxycycline significantly reduces postoperative infections and is superior to doxycycline alone. The effect of an agent active only against anaerobic microorganisms was tested in a double-blind study of 267 patients who underwent elective colorectal surgery. The patients received either tinidazole (1600 mg) and placebo or tinidazole (1600 mg) and doxycycline (400 mg) as a single preoperative infusion. Patients who received tinidazole and doxycycline had significantly fewer infectious complications, reoperations, additional use of antibiotics, and a shorter hospital stay. Microbiologic studies demonstrated that tinidazole alone gave effective protection against anaerobic organisms but did not protect the patients from aerobic gram-negative infectious complications. A single preoperative dose of antimicrobial agents effective against both anaerobic and aerobic bowel organisms seems to be the preferred prophylaxis for patients undergoing colorectal surgery.

Adolescent↗
PubMedDate not supplied

[Method of culturing microorganisms at constant concentrations of the nutrient components].

A method for batch cultivation of microorganisms in a flow medium is described, characterized by slight changes in concentrations of medium components in time and by the absence of products of vital activity of microorganisms in the fermentation medium. The conditions are achieved due to application of a fermentation installation with a microfiltrative membrane that separates the cells of cultivated microorganisms from the culture fluid and due to increasing the flow rate to a value at which the inlet and outlet concentrations of the medium components are almost equal. The cells of cultivated microorganisms under such conditions remain in the fermentation medium volume. The system was called "Ekostat". If the process is performed in "Ekostat" system, a positive deviation from the logarithmic law is observed for the growth rate of the yeast Candida utilis VSB-651 on ethanol cultivation.

Candida↗
PubMed1985

A survey of buoyant density of microorganisms in pure cultures and natural samples.

Values of buoyant density of microorganisms reported in literature are widely divergent because of techniques used. Many of these involve centrifugation in density gradients formed by substances with high osmolarity which dehydrate the cells. In order to better understand the ranges of variation of density of microbial cells several approaches were taken. Firstly, samples from several natural aquatic habitats were taken and the densities of the microorganisms present determined. Secondly, experiments were performed with selected microorganisms to maximize density changes by forcing them to accumulate intracytoplasmic inclusions of dense materials or to loose their capsules. Finally, the relevant literature was reviewed. It could be demonstrated that most microorganisms have a density around 1.080 pg microns-3 when measured in low osmolarity media such as Percoll. However, many species are able to modify their density by as much as 7% (for instance, from 1.097 to 1.022 pg microns-3 in Thiocapsa roseopersicina, and similar variations in other bacteria), by incorporating substances into inclusions (sulfur, carbon, phosphorous storage materials, etc.), or by making capsules and/or gas vesicles. The relevance of buoyant density determinations for several aspects of microbial ecology and physiology is discussed.

Bacteria↗