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PubMedDate not supplied

[Microorganisms of Lake Baikal and Lake Nyasa as indicators of anthropogenic influence: prospects of use in biotechnology].

Restriction endonucleases (RENs) were detected in 650 microbial strains isolated from water columns and bottom sediments of deep rift lakes, Baikal (Russia) and Nyasa (Southeastern Africa). They enzymes included unique (Fan I, Aca I, and Sse 91) and very rare (Bsi I, and Cci N I) species not typical of aquatic ecosystems. Water columns, deep cores, and bottom sediments of pure areas of the lakes contained no microorganisms with new RENs. Thus, inshore areas of Lake Baikal exposed to anthropogenic influence may contain mutant bacterial strains expressing RENs that have not been described previously.

Africa South of the Sahara↗

PubMed1989

Use of polymerase chain reaction for diagnosis of inherited disorders.

The polymerase chain reaction (PCR) is a rapid method for generating a 10(6)- to 10(7)-fold increase in the number of copies of a discrete DNA or RNA sequence. The technique is being used for rapid prenatal diagnosis and carrier testing of several inherited disorders. After PCR, mutations producing single-gene disorders can be detected by several different methods, including endonuclease digestion and gel electrophoresis (applicable when a mutation affects an endonuclease recognition site), gel electrophoresis (used for detection of deletions), and hybridization to an oligonucleotide probe specific for a mutation. Less often, gene sequencing of a PCR product is used to rapidly identify a mutation. In addition, the PCR technique can be applied to polymorphism analysis to provide diagnosis by linkage analysis. In other areas, PCR is being used to detect and characterize microbial pathogens and to characterize mutations associated with carcinogenesis. The PCR method is useful in situations in which the amount of DNA sample is limited, such as in forensics and prenatal testing, or in which the quality of the DNA sample is poor.

DNA-Directed DNA Polymerase↗

PubMed1988

[Various approaches to the search for the producers of bacteriocin-like substances among bacteria of the genus Pseudomonas].

Some methods providing rapid and methodically simple study of large microbial collections and detection of cultures producing bacteriocin-like substances perspective for further investigation are described. The use of cellophane disks and study of the proteolytic enzyme effects allowed the authors to detect organisms producing high molecular antibiotics of protein nature.

Bacteriocins↗

PubMed1985

Amino acid stability and microbial growth in total parenteral nutrient solutions.

The stability of amino acids in total parenteral nutrient (TPN) solutions stored for 30 days and the potential for stored TPN solutions to support growth of microbial contaminants were studied. Solutions of 3.5% crystalline amino acids and 25% dextrose with electrolytes were prepared either by using a commercially available amino acid solution with electrolytes or by adding electrolytes individually to a base TPN solution. Solutions were stored in polyvinyl chloride bags at refrigerated (4 degrees C) or room (25 degrees C) temperature for 30 days. Some bags were inoculated with Candida albicans or Pseudomonas maltophilia before storage to serve as positive controls for evaluation of microbial contamination. At appropriate intervals, bags of each type of solution under each storage condition were analyzed for amino acid content. Microbial growth was evaluated by filtering the contents of each bag and incubating the filter in brain-heart infusion broth. No microbial growth was detected in any of the study solutions, but all solutions inoculated with C. albicans and 2 of 16 solutions inoculated with Ps. maltophilia had evidence of growth. No significant decreases in the concentrations of any of the amino acids were noted for solutions stored at refrigerated temperature, but significant decreases in the concentrations of arginine and methionine were noted for solutions stored at room temperature. Total parenteral nutrient solutions can be stored for up to 30 days if they are kept at refrigerated temperatures and protected from light; however, quality assurance measures for these solutions should include end-product microbiologic testing.

Amino Acids↗

PubMed2026

[Comparative analysis of comprehensive treatment outcomes in patients with chronic bacterial prostatitis with the addition of the multicomponent complex AndrOPREN].

INTRODUCTION: Type II chronic bacterial prostatitis is characterized by persistent infection, insufficient efficacy of standard therapy, and a high recurrence rate, which necessitates the search for additional treatment options. AIM: To evaluate the efficacy and safety of adding the multicomponent complex AndrOPREN to comprehensive therapy for type II chronic bacterial prostatitis. MATERIALS AND METHODS: This prospective, comparative, randomized study included 233 patients allocated to the main group (n=126) and the control group (n=107). In both groups, patients received standard therapy; men in the main group additionally received the multi-ingredient complex AndrOPREN at a dose of two capsules of No. 1 and two capsules of No. 2 daily for 1-2 months. The follow-up period was 60 days. Changes in symptoms according to the IPSS and QoL scores, urinalysis parameters, microscopy findings of expressed prostatic secretions, pathogen eradication, and biochemical safety parameters were assessed. RESULTS: Improvement was observed in both groups and was more pronounced in the main group. By day 14, the median IPSS score was 14.0 [12.0; 16.0] vs. 18.0 [15.0; 20.0] in the control group (p<0.001); by day 60, the corresponding values were 7.0 [5.0; 9.0] and 11.0 [9.0; 13.0] (p<0.001). At the end of follow-up, the QoL score was 2.0 [1.0; 2.0] and 3.0 [2.0; 3.0], respectively. No microbial growth was detected in 91.2% and 80.4% of patients, respectively (p=0.026); Escherichia coli eradication was achieved in 91.7% and 76.9%, respectively. No biochemical changes indicative of nephrotoxicity or hepatotoxicity were detected. DISCUSSION: The addition of the multicomponent complex AndrOPREN was associated with more rapid symptom resolution, a reduction in inflammatory changes, restoration of the secretory function of the prostate, and greater microbiological efficacy. CONCLUSION: The addition of the multicomponent complex AndrOPREN to comprehensive therapy for type II chronic bacterial prostatitis improves treatment efficacy while maintaining a favorable safety profile.

Humans↗

PubMed1982

[Carbamoyl phosphate biosynthesis in Streptococci].

Nine streptococcal strains belonging to different serological groups (A, B, C, D) were shown to synthesize carbamoyl phosphate from ammonium hydrocarbonate and ATP. The reaction was catalyzed by carbamate kinase (EC 2.7.2.2). The speed of the reaction was evaluated according to the increase of the content of citrullin (the combination of carbamate kinase and ornithine transcarbamoylase). The representatives of different serological groups were found to have quantitative differences in carbamate kinase activity: the highest specific activity (13 nmol of citrullin per minute in 1 mg of dried microbial biomass) was detected in group A streptococci, while group D streptococci showed the lowest specific activity (0.5 nmol).

Carbamates↗

PubMed1984

Preparation and sterilization by filtration of Renacidin irrigation.

A method for the sterilizing filtration of Renacidin, a urologic irrigating solution, was evaluated. Renacidin irrigation was prepared and sterilized by microporous membrane filtration. A sterilizing membrane filtration apparatus was challenged by inoculating a batch of irrigation solution with Escherichia coli. The sterility of both intentionally contaminated and routinely prepared batches was evaluated. The stability of the solution was monitored by pH measurement, visual examination, maintenance of a vacuum, and absorbance spectrum of a 1:100 dilution in deionized water over a wavelength range from 400 to 200 nm. The time required to prepare three one-liter units was about two hours. No microbial growth was detected in any of the samples. The predicted minimum shelf-life at 10 degrees C was six months. Because the prepared solution contains some unreacted citric acid and bicarbonates, storage at room temperature could produce excessive pressure inside the container from carbon dioxide gas evolution. Refrigerated storage is recommended. This method for the preparation and sterilization of Renacidin irrigation is reasonably expedient, economical, and reliable.

Chemical Phenomena↗

PubMed1983

[Aerobic and facultatively anaerobic bacteria isolated from surgical infection patients].

The ecological structure of infections in surgical patients with different postoperative complications (suppurative wounds, abscesses, peritonitis, etc.) and suppurative lung diseases were studied. During the period of 6 years (1975-1980) 5401 samples of clinical material were studied. 1380 samples (25.6%) were sterile, from 2254 samples (41.7%) monocultures were isolated, in 1767 samples (32.7%) microbial associations were detected. Of 5962 isolated cultures, 1816 (30.5%) were Gram-negative bacteria (GNB), 3532 (59.2%) were Gram-positive bacteria (GPB) and 614 (10.6%) were yeastlike fungi. The tendency towards the increase of the role of GNB in the etiology of postoperative complications was observed. Among GNB Pseudomonas aeruginosa strains were prevalent (36.2%). In the group of GPB coagulase-negative staphylococci were rather frequently found to be the causative agents of surgical infections.

Bacteriological Techniques↗

PubMed1978

Recommended procedures for in-use testing of large volume parenterals suspected of contamination or of producing a reaction in a patient. National Coordinating Committee on Large Volume Parenterals.

Guidelines for hospital detection of possible microbial contaminants of large volume parenterals are presented. Operational definitions are given, and the guidelines are divided into procedures or steps (1) to be taken in the patient care area by its personnel and that are practical for application in the hospital microbiological laboratory with limited facilities, and (2) those for the expert microbiological laboratory of health departments, teaching hospitals, large community hospitals or specialized research laboratories with experience and responsibility for handling more detailed procedures.

Drug Contamination↗

PubMed1996

Acinetobacter radioresistens metabolizing aromatic compounds. 1. Optimization of the operative conditions for phenol degradation.

A strain of Acinetobacter radioresistens was able to utilize phenol as the only carbon and energy source, after an acclimatization period of 3 days in which increasing phenol concentrations from 50 to 200 mg/l were supplied. At 30 degrees C, the complete phenol utilization in batch degradation tests occurred in 2.5-3 h at pH 7 and 8, but it increased strongly at pH 6 (over 40 h). No microbial growth was detected at 40 degrees C, while at 20 degrees C (pH 7-8) the time necessary for complete phenol degradation was about twofold longer than that at 30 degrees C (pH 7-8) revealing a good capability of the strain as a seed-micro-organism for enhancing phenol degradation. The bacterial growth in acclimatized cultures, evaluated with the viable cell count, always displayed a trend consistent with the use of phenol as a substrate with an eventual lag phase and then an exponential phase, while in the non-acclimatized cultures an initial stage of cellular death was observed.

Acinetobacter↗

PubMed1985

Increased detection of staphylococcal bacteremia using an anti-microbial removal device.

During the period of August 16, 1981, through December 16, 1982, 15-mL blood culture specimens collected at the Seattle Veterans Administration Medical Center (SVAMC) were divided into two aliquots. The first 10-mL aliquot was inoculated directly into aerobic and anaerobic BACTEC (Johnston Laboratories, Towson, MD) vials (DIR); the remaining 5 mL was processed in an resin-containing Antimicrobial Removal Device (Marion Scientific, Kansas City, MO) before transfer to a second, identical set of aerobic and anaerobic vials (ARD). The final volume of inoculated blood from the ARD specimen was half that of the DIR specimen. Both sets of vials were processed using the BACTEC radiometric detection system. One hundred fifty specimen pairs grew 161 significant pathogens; 43 isolates were recovered only from the ARD sample, 39 only from the DIR samples, and 79 from both. Of the 35 isolates recovered from patients receiving anti-microbial agents active against the isolated pathogens, 21 were recovered only from the ARD specimen and 5 only from the DIR specimen (P less than 0.005). Of the 15 S. aureus strains isolated from patients on therapy, 12 were recovered only from the ARD specimen, 2 only from the DIR sample, and 1 from both samples (P less than 0.01). Ten of the 32 isolates of S. aureus recovered from antibiotic-free patients were found only in the ARD specimen and three only in the DIR specimen (P = 0.05). The ARD specimens recovered significantly more S. aureus from all patients regardless of antibiotic status.

Bacteriological Techniques↗

PubMed2002

Quantitative microbiological study of human carious dentine by culture and real-time PCR: association of anaerobes with histopathological changes in chronic pulpitis.

The bacteria found in carious dentine were correlated with the tissue response of the dental pulps of 65 teeth extracted from patients with advanced caries and pulpitis. Standardized homogenates of carious dentine were plated onto selective and nonselective media under anaerobic and microaerophilic conditions. In addition, real-time PCR was used to quantify the recovery of anaerobic bacteria. Primers and fluorogenic probes were designed to detect the total anaerobic microbial load, the genera Prevotella and Fusobacterium, and the species Prevotella melaninogenica, Porphyromonas endodontalis, Porphyromonas gingivalis, and Micromonas (formerly Peptostreptococcus) micros. The pulpal pathology was categorized according to the cellular response and degenerative changes. Analysis of cultured bacteria showed a predominance of gram-positive microorganisms, particularly lactobacilli. Gram-negative bacteria were also present in significant numbers with Prevotella spp., the most numerous anaerobic group cultured. Real-time PCR analysis indicated a greater microbial load than that determined by colony counting. The total number of anaerobes detected was 41-fold greater by real-time PCR than by colony counting, while the numbers of Prevotella and Fusobacterium spp. detected were 82- and 2.4-fold greater by real-time PCR than by colony counting, respectively. Real-time PCR also identified M. micros, P. endodontalis, and P. gingivalis in 71, 60, and 52% of carious samples, respectively. Correlation matrices of the real-time PCR data revealed significant positive associations between M. micros and P. endodontalis detection and inflammatory degeneration of pulpal tissues. These anaerobes have been strongly implicated in endodontic infections that occur as sequelae to carious pulpitis. Accordingly, the data suggest that the presence of high levels of these bacteria in carious lesions may be indicative of irreversible pulpal pathology.

Bacteria, Anaerobic↗

PubMed2006

Capillary isoelectric focusing of microorganisms in the pH range 2-5 in a dynamically modified FS capillary with UV detection.

The isoelectric points of many microbial cells lie within the pH range spanning from 1.5 to 4.5. In this work, we suggest a CIEF method for the separation of cells according to their isoelectric points in the pH range of 2-5. It includes the segmental injection of the sample pulse composed of the segment of the selected simple ampholytes, the segment of the bioanalytes and the segment of carrier ampholytes into fused silica capillaries dynamically modified by poly(ethylene glycole). This polymer dissolved in the catholyte, in the anolyte and in the injected sample pulse was used for a prevention of the bioanalyte adsorption on the capillary surface and for the reduction of the electroosmotic flow. Between each focusing run, the capillaries were washed with the mixture of acetone/ethanol to achieve the reproducible and efficient CIEF. In order to trace of pH gradients, low-molecular-mass pI markers were used. The mixed cultures of microorganisms, Escherichia coli CCM 3954, Candida albicans CCM 8180, Candida parapsilosis, Candida krusei, Candida glabrata, Candida tropicalis, CCM 8223, Proteus vulgaris, Klebsiela pneumoniae, Staphylococcus aureus CCM 3953, Streptococcus agalactiae CCM 6187, Enterococcus faecalis CCM 4224 and Staphylococcus epidermidis CCM 4418, were focused and separated by the CIEF method suggested here. This CIEF method enables the separation and detection of the microbes from the mixed cultures within several minutes. The minimum detectable number of microbial cells was less than 10(3).

Electrophoresis, Capillary↗

PubMed1977

The use of yeast cultures for the detection of environmental mutagens using a fluctuation test.

A microbial fluctuation test, modified for the detection of environmental mutagens has been evaluated using a number of strains of the yeast Saccharomyces cerevisiae. Auxotrophic diploid cultures of yeast which produce prototrophic colonies by both mitotic gene conversion and mutation have been extensively utilized for the detection and evaluation of chemicals showing genetic activity. A number of the yeast strains utilized were shown to be suitable for use in the fluctuation test although the time scales of the experiments were considerably extended (up to 16 days) compared to those involving bacteria. The yeast strains respond to doses of mutagens at least a 100-fold lower than that required in a conventional short exposure treat and plate experiment. In experiments involving the induction of mitotic gene conversion at the tryptophan-5 and histidine-4 loci in the fluctuation test significant increases in prototrophic cells were produced in the presence of the insecticide Lindex (0.05 microng/ml), the preservative Thiomersal (0.0001 microng/ml), a mahogany hair dye (0.01 microng/ml), the herbicide Paraquat (0.02 microng/ml) and the alkylating agent ethyl methane sulphonate (0.1 microng/ml). The results demonstrate that the fluctuation test provides an extremely sensitive assay for the detection of chemicals which show genetic activity in yeast at non-toxic concentrations.

Biological Assay↗

PubMed2004

Clinical evaluation of affirm VPIII in the detection and identification of Trichomonas vaginalis, Gardnerella vaginalis, and Candida species in vaginitis/vaginosis.

OBJECTIVE: To compare the Affirm VPIII Microbial Identification Test for detection and identification of Candida species, Gardnerella vaginalis and Trichomonas vaginalis to clinical and microscopic criteria commonly used to diagnose vaginitis. METHODS: Women that were symptomatic for vaginitis/vaginosis and asymptomatic women being seen for routine obstetric or gynecological care were included in this study. Women treated with antibiotics or antifungals within one week or women who had douched within 24 hours were excluded. Two vaginal swab specimens were simultaneously obtained from each patient, one swab was placed in sterile physiological saline for immediate microscopic wet mount examination and KOH testing. The other swab was placed in the Affirm collection tube for Affirm VPIII testing based on previously demonstrated methods. RESULTS: The Affirm assay was significantly more likely to identify Gardnerella and Candida than wet mount. 190 (45%) were positive for Gardnerella by Affirm compared to 58 (14%) by wet mount; 45 (11%) were positive for Candida by Affirm compared to 31 (7%) by wet mount; and 30 (7%) were positive for Trichomonas by Affirm compared to 23 (5%) by wet mount. Symptomatic women were significantly more likely to be positive by Affirm only (23% vs. 10%), wet mount only (3% vs. 2%) or Affirm and wet mount (15% vs. 1%). Asymptomatic women were significantly more likely to be negative for Affirm and wet mount (43% vs. 5%). CONCLUSIONS: The Affirm VPIII test is a more sensitive diagnostic test for detection and identification of symptomatic vaginitis/vaginosis than conventional clinical examination and wet mount testing.

Animals↗

PubMed2003

Viral and microbial genotyping by a combination of multiplex competitive hybridization and specific extension followed by hybridization to generic tag arrays.

Detection and identification of microbial pathogens are important for disease diagnosis, treatment and prophylaxis measurements. By introducing an innovative technique, we show a robust, reliable and accurate microarray-based method for identification of microbial pathogens. The technique utilizes a unique combination of multiplex competitive hybridization, which enhances hybridization accuracy of oligonucleotides to the specific target, and apyrase-mediated allele-specific extension, which improves specific extension. As a model system, different clinically relevant human papillomaviruses were selected for this study. The method generated accurate results and proves to be promising for specific and correct microbial and viral typing.

DNA Primers↗

PubMed2004

Characterization of humus microbial communities in adjacent forest types that differ in nitrogen availability.

To address the link between soil microbial community composition and soil processes, we investigated the microbial communities in forest floors of two forest types that differ substantially in nitrogen availability. Cedar-hemlock (CH) and hemlock-amabilis fir (HA) forests are both common on northern Vancouver Island, B.C., occurring adjacently across the landscape. CH forest floors have low nitrogen availability and HA high nitrogen availability. Total microbial biomass was assessed using chloroform fumigation-extraction and community composition was assessed using several cultivation-independent approaches: denaturing gradient gel electrophoresis (DGGE) of the bacterial communities, ribosomal intergenic spacer analysis (RISA) of the bacterial and fungal communities, and phospholipid fatty acid (PLFA) profiles of the whole microbial community. We did not detect differences in the bacterial communities of each forest type using DGGE and RISA, but differences in the fungal communities were detected using RISA. PLFA analysis detected subtle differences in overall composition of the microbial community between the forest types, as well as in particular groups of organisms. Fungal PLFAs were more abundant in the nitrogen-poor CH forests. Bacteria were proportionally more abundant in HA forests than CH in the lower humus layer, and Gram-positive bacteria were proportionally more abundant in HA forests irrespective of layer. Bacterial and fungal communities were distinct in the F, upper humus, and lower humus layers of the forest floor and total biomass decreased in deeper layers. These results indicate that there are distinct patterns in forest floor microbial community composition at the landscape scale, which may be important for understanding nutrient availability to forest vegetation.

Bacteria↗

PubMed2005

How Toll-like receptors and Nod-like receptors contribute to innate immunity in mammals.

Innate immune detection of pathogens relies on specific classes of microbial sensors called pattern-recognition molecules (PRM). In mammals, such PRM include Toll-like receptors (TLRs) and the intracellular proteins NOD1 and NOD2, which belong to the family of Nod-like receptors (NLRs). Over the last decade as these molecules were discovered, a function in innate immunity has been assigned for the majority of them and, for most, the microbial motifs that these molecules detect were identified. One of the next challenges in innate immunity is to establish a better understanding of the complex interplay between signaling pathways induced simultaneously by distinct PRMs and how this affects tailoring first-line responses and the induction of adaptive immunity to a given pathogen.

Adaptor Proteins, Signal Transducing↗