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We aimed to evaluate colonisation patterns of Akkermansia muciniphila in a Greek adult population and to investigate model-adjusted associations of A. muciniphila with host adiposity and cardiometabolic markers. Participants (n=125) underwent anthropometric, dietary, physical activity and lifestyle evaluation. Blood sampling for determination of blood lipid indices, glucose metabolism, adiponectin, lipoprotein-associated phospholipase A2 (Lp-PLA2), inflammation and oxidative stress parameters was also performed. Stool A. muciniphila presence and levels were determined by quantitative PCR and subjects were grouped based on bimodal distribution of levels (Low vs High). A. muciniphila was detected in 88.6% of participants. Overweight/obese (OW/OB) subjects were more prone in low bimodal levels of A. muciniphila compared to normal-weight (NW) individuals (58.75 vs 27.59%, P=0.004), with a 4-time greater likelihood after multi-adjusted logistic regression analysis (P=0.016). Levels of A. muciniphila were negatively associated with total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C) ratio (log10:-0.009±0.004, P=0.033), whereas detection of this bacterium was negatively associated with both TC/HDL-C ratio (log10: -0.049±0.023, P=0.036) and low-density lipoprotein cholesterol/HDL-C ratio (-0.407±0.176, P=0.023). Furthermore, low bimodal levels of A. muciniphila were positively associated with fasting blood glucose (log10: 0.018±0.009, P=0.037). In terms of inflammation markers, levels of A. muciniphila were positively associated with soluble cluster of differentiation-14 (sCD14) (log10: 0.012±0.004, P=0.003) and faecal detection of this bacterium had a positive association with anti-inflammatory interleukin 10 levels (log10: 0.325±0.131, P=0.015). In addition, A. muciniphila levels were positively associated with total adiponectin (log10: 0.046±0.015, P=0.002), whereas low bimodal levels of A. muciniphila had an inverse relationship with this blood marker (log10: -0.131±0.053, P=0.016). In conclusion, we confirmed the previously reported association of A. muciniphila with metabolic health for the first time in a Greek urban population; furthermore, we shed some light to novel atherosclerotic risk markers with rather unexplored connections with A. muciniphila colonisation patterns in human subjects.

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Electrophoresis is widely applied in the field of biochemistry and molecular biology. Tetrapolar electrical impedance sensing (TEIS) has been shown capable of replacing the conventional detection technology in order to develop a point of care electrophoretic analyzer. Besides the advantages of reduced influence of electrode polarization, TEIS is affected by sensitivity distribution depending on the electrode design. A well reported practice outside of electrophoresis, systematic investigation of the effects of sensitivity distribution on the TEIS in microfluidic devices has not been conducted. Here we utilize finite element modeling, backed by experimental results, to optimize the sensor design within an electrophoretic separation device. Numerous sensor designs were validated regarding detectability, sensitivity and spatial resolution. The results show, that minimizing the distance between the central/pick-up electrodes increases sensitivity and spatial resolution whereas the distance between the central electrodes and the outer electrode do not influence sensitivity and spatial resolution.

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OBJECTIVE: It is recognized that measurement of ACTH-precursor peptides including proopiomelanocortin (POMC) has clinical utility in identifying the aetiology of Cushing's syndrome. Recent data have also demonstrated cross-reactivity of POMC in ACTH immunoassays used in clinical laboratories. The aim of this study was to assess the cross-reactivity of POMC in the main commercial immunoassays for ACTH and to survey the awareness of laboratory professionals to this potential interference. METHOD: To assess cross-reactivity, specimens containing ACTH and/or POMC were prepared by the UK National External Quality Assessment Service (UK NEQAS) [Edinburgh]. A separate interpretative exercise was also sent to participating laboratories. RESULTS: Eighty-seven laboratories measured 'total' ACTH (i.e. ACTH and/or POMC) in their assays. Cross-reactivity of POMC varied from a mean of 1·6-4·7% (reflected in a large percentage increase in measured ACTH of up to 261% due to POMC cross-reactivity) depending on the manufacturer. Major differences in the clinical interpretation of test results were observed in returned responses to the interpretative exercise. CONCLUSION: An appraisal of POMC cross-reactivity in currently available ACTH immunoassays has been achieved. Cross-reactivity was sufficient to detect ACTH precursors at concentrations that could be found in patients with ectopic ACTH syndrome. These data will assist laboratories in interpreting results when assessing the hypothalamic-pituitary-adrenal axis. Endocrinologists and laboratory professionals should be aware of the degree of cross-reactivity in ACTH immunoassay in order to minimize the risk of misinterpretation of results and/or potentially delayed treatment.

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UNLABELLED: To assess continuous subcutaneous hydrocortisone infusion (CSHI) in patients with adrenocortical insufficiency (AI) and difficulties with oral replacement. Three patients with AI and frequent hospital admissions attributed to adrenal crises were treated with CSHI, which was delivered via a continuous subcutaneous infusion. All three patients preferred CSHI and remained on it long term, which permitted prolonged follow-up analysis. All three patients reported symptomatic improvement, and in two cases, reduced hospital admission rates and inpatient stay lengths were observed. The cost of hospital admissions and overall treatment was reduced in all cases. CSHI offers a practical and acceptable alternative to oral replacement in a subset of patients with AI. The cost of initiating and maintaining the pump is offset in the long term by reduced frequency and duration of emergency admissions. CSHI can therefore be considered in a select group of patients who are resistant to treatment with conventional oral glucocorticoids. LEARNING POINTS: Continuous subcutaneous infusion of cortisol is a viable alternative in patients unable to take oral steroids.Patient acceptability was high, with three out of three patients preferring to remain on pump treatment.Hospital admissions were reduced in response to pump therapy, which compensated for the increased treatment cost.The daily dosage of hydrocortisone can be reduced by using pump therapy.

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BACKGROUND: Perivascular epithelioid cell neoplasm (PEComa) is a rare mesenchymal tumor. Gynecological PEComas account for just over one-fourth of the overall PEComa cases reported in the literature. Surgery is the most recommended primary treatment while adjuvant therapy is generally reserved for high-risk cases. However, the best management of this neoplasia has not been well established, primarily because of the paucity of cases described to date. OBJECTIVES: The aim of this systematic review is to summarize what is known thus far regarding the etiopathogenesis, clinical and pathologic features of PEComas, focusing also on the most valid treatment options for uterine cases. DATA SOURCES: Pubmed articles on PEComas published in various journals over the past 70 years were analyzed. CONCLUSIONS AND KEY FINDINGS: Although the optimal treatment of gynecological PEComas is controversial, surgical resection remains the cornerstone. The use of adjuvant treatment is warranted in high risk patients to increase disease control. A multidisciplinary approach should be key in treatment decision-making regarding gynecological PEComas.

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OBJECTIVE: The objective of this study is to determine the potential effect of oral L-arginine supplementation on intestinal inflammation in very low birth weight (VLBW) neonates, as estimated by faecal calprotectin levels. STUDY DESIGN: The study enrolled 83 VLBW neonates with birth weight ≤1500 g and gestational age ≤34 weeks. In this double-blind study, 40 neonates received daily oral L-arginine supplementation of 1.5 mmol kg(-1) per day between the 3rd and 28th day of life, and 43 neonates placebo. Stool samples were collected on days 3, 14 and 28, and calprotectin was measured by enzyme-linked immunosorbent assay. RESULT: Calprotectin values significantly decreased over time in both groups (P=0.032). No difference in faecal calprotectin values was recorded between neonates receiving arginine supplementation and neonates receiving placebo at days 3, 14 and 28. CONCLUSION: Faecal calprotectin values decrease with increasing postnatal age in VLBW infants, but this is not related to arginine supplementation.

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Researchers believe that human muscle-derived cells are able to restore leak-point pressure to normal levels by differentiating into new muscle fibres that prevent anal sphincter muscle atrophy. Laboratory data are needed to identify exactly how these cells work to regenerate muscle. The objective of this study is to test whether stem cells can be employed to treat internal anal sphincter (IAS) injuries in humans; to this end, this work will use a two-step process to study: first, the effectiveness of the treatment in a sample of animals with artificial injuries to the IAS and then to verify the results in a population of selected humans affected by pathology.

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Lactobacilli are believed to be beneficial for the human hosts and are currently being evaluated as potentially probiotic bacteria. In this study, Lactobacillus strains were isolated from infant faeces and were examined in vitro for potential probiotic properties. Faecal specimens from 63 healthy, full-term infants were collected at 4, 30 and 90 days after delivery. Seventy-four Lactobacillus strains were isolated and one or more different phenotypes from each infant (n = 44) were selected for further testing. The bacterial isolates were identified mainly as L. gasseri, L. crispatus, Lactobacillus paracasei, L. salivarius, L. fermentum after amplification and sequencing of 16s rRNA gene. The strains were examined for acid and bile tolerance, adhesion to Caco-2 cells, antibiotic susceptibility and antimicrobial activity against selected enteric pathogens. The great majority of the isolated lactobacilli were susceptible to ampicillin, amoxicillin/clavulanic acid, tetracycline, erythromycin, cephalothin, chloramphenicol and rifampicin. Resistance to vancomycin or bacitracin was detected to 34% of the strains. Twenty strains out of forty-four exhibited significant tolerance to bile salts. Those strains were subsequently tested for resistance to low pH conditions (pH 2 and 3). Interestingly, 85% (17 strains) of the tested lactobacilli remained unaffected at pH 3 after 3 h of incubation, 6 strains were found resistant at pH 2 after 1.5 h and only 2 strains found resistant after 3 h of incubation. Two of the strains were able to adhere to Caco-2 cells. In conclusion, two isolates fulfilled the in vitro probiotic criteria and are good candidates for further in vivo evaluation.

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Banana is a widely consumed fruit, which contains considerable amounts of potential prebiotic indigestible carbohydrates. In our randomised, controlled trial we aimed to evaluate the in vivo prebiotic effect of banana consumption on faecal microbiota. Thirty-four healthy women participated in the study, having Body Mass Index (BMI) 24-30 kg/m(2), age 19-45 years, without history of gastrointestinal disease and no antibiotic and other medication use two months prior the initiation and during the study. All women were asked to maintain their usual dietary habits for 60 days and they were randomly assigned to consume twice a day a pre-meal snack, either one medium banana, or one cup of banana-flavoured drink or one cup of water (control group). Stool samples were collected at baseline, on days 30 and 60 of intervention for enumeration of total anaerobes, bifidobacteria and lactobacilli by plate count techniques, as well as for pH and short chain fatty acids (SCFAs) measurement. Gastrointestinal symptoms were also recorded. Mean bifidobacterial levels were increased only in the banana group both at 30 and 60 days of intervention, but this change did not reach a statistical significance. No significant overall differences in the total concentrations and molar ratios of SCFAs were detected according to dietary intervention. Analysis of the gastrointestinal symptoms records revealed significantly lower bloating levels in the banana group, compared to controls, at 26-35 days (p = 0.009) and 51-60 days (p = 0.010). Banana consumption had also no adverse effects on evacuation patterns. We concluded that daily consumption of bananas is a well-tolerated eating behaviour, which may induce bifidogenesis in healthy women experiencing body weight problems.

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Beta-glucans are polysaccharides present in the cell walls of higher plants, in the seeds of some cereals, and certain yeasts and fungi also produce them. It is suggested that they exhibit, among many other health benefits, protective effects against carcinogenesis in the colon, but there is not enough human data to support this. The aim of the study was to determine the effect of barley-derived beta-glucan in the gut microbiota of polypectomized patients. Subjects were randomly assigned to consume 125 g of bread per day with beta-glucan (3 g/d), or without (placebo group), for 3 months. Thirty-three polypectomized men and women (mean age 57.6 years) were recruited into the study, but only 20 completed. Subjects did not consume any probiotics, prebiotics or antibiotics 2 months prior the intervention, or during the study. Stool samples were collected at baseline, on days 30 and 90 of intervention, as well as 2 weeks after the intervention, for enumeration of total aerobes and anaerobes, coliforms, E. coli, enterococci, Bacteroides spp., Clostridium perfringens, bifidobacteria, lactobacilli and Candida spp. Faecal bacterial enzyme activity (beta-glucuronidase and beta-glucosidase), pH, faecal moisture and the concentration of volatile fatty acids in the faeces were measured. Gastrointestinal symptoms were also recorded. Overall, no significant differences were observed in bacterial viable counts between the two feeding groups. Group specific analysis for ß-glucan group revealed significantly decreased total coliform counts on the 30th day of the trial compared to the baseline (p = 0.041). Clostridium perfringens concentration increased without reaching statistical significance, on the 30th day, while it decreased significantly on the 90th day of the intervention compared to the 30th day (p = 0.016). An increase was noted in the molar ratio of acetate on the 90th day of the trial compared to placebo (p = 0.018). The molar ratio of butyrate presented a trend to increase on the 30th day, which decreased (p = 0.013) on the 90th day and then increase 2 weeks after the intervention (p = 0.017) compared to placebo. A decrease was recorded in the ß-glucan group in the bloating and abdominal pain score after the 30th day of the intervention (Day 30-37) compared to placebo. During ß-glucan administration we did not observe any changes on beta-glucuronidase or beta-glucosidase activity, faecal pH, or on faecal moisture.

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The fate and effect of the herbicides linuron and metribuzin on the co-composting of sewage sludge and green waste were addressed in this work. The experiments were conducted in metal cubic containers of 1.0m(3) volume simulating a windrow composting system. A mixture of sludge and green waste was prepared at a ratio of 1:5 v/v. The mixture was split in four equal parts and the two herbicides were added, using a pressure sprayer, as sole or mixed pollutant in each of the three mixtures. The forth mixture was composted without any addition of herbicide, to serve as control. Temperature, physicochemical characteristics, herbicide concentration, carbon dioxide emission, methane emission and microbiological parameters were measured either daily or every time the mixtures were turned, for a period of 80 days. Both herbicides' concentration decreased significantly resulting in removal efficiencies of 99.1-99.7% and 95.8-96.0% for linuron and metribuzin, respectively. Incubation of microbiologically inactive mixtures at a temperature schedule following the spontaneous temperature evolution in the composters resulted in very little (1-11%) decomposition for both herbicides. Comparison of the variation of physicochemical parameters and microbial populations during composting indicated that both herbicides did not affect the composting process.

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Increasing use of antibiotics for the treatment of infectious diseases and also for non-therapeutic reasons (agriculture, animal husbandry and aquaculture) has led to the increasing incidence of antibiotic resistance and the ineffectiveness of antimicrobial treatment. Commensal intestinal bacteria are very often exposed to the selective pressure of antimicrobial agents and may constitute a reservoir of antibiotic resistance determinants that can be transferred to pathogens. The present study aimed to investigate the antibiotic susceptibility profile and the presence of selected resistance genes in cocci isolated from the faecal microbiota of 35 healthy, full-term infants at 4, 30 and 90 days after delivery. A total of 148 gram-positive, catalase-negative cocci were isolated and tested for susceptibility to 12 different antibiotics by disk-diffusion technique. Multiplex PCR analysis was performed for the identification of Enterococcus spp. isolates and the simultaneous detection of vancomycin-resistance genes. PCR-based methodology was used also for identification of tetracycline and erythromycin resistance determinants. Identification results indicated E. faecalis as the predominant species (81 strains), followed by E. faecium, E. casseliflavus/E. flavescens and E. gallinarum. High prevalence of resistance to tetracycline (39.9%), erythromycin (35.1%), vancomycin (19.6%) and to nucleic acid synthesis inhibitors was detected. PCR data revealed 24 out of 52 erythromycin-resistant isolates carrying the ermB gene and 32 out of 59 tetracycline-resistant strains carrying tet genes, with tet(L) determinant being the most frequently detected. Only intrinsic vancomycin resistance (vanC1 and vanC2/C3) was reported among tested isolates. In conclusion, erythromycin and tetracycline acquired resistant traits are widespread among faecal cocci isolates from Greek, healthy infants under no apparent antimicrobial selective pressure.

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Wastewater sludge and wood chips were used as feedstock for the construction of two piles, Pile I ("PI") and Pile II ("PII"), at a ratio of 1:1 and 1:2 v/v, respectively. Each pile was originally 1.3-m high, 2.0-m wide, and approximately 9.0-m long. A mechanical turner was used to turn the two windrows every 1 to 2 weeks. Three 500-mL-volume glass funnels were inverted and introduced into each pile: one in the core (named, respectively, "PIC" and "PIIC"), one at the top ("PIT" and "PIIT"), and one at the side ("PIS" and "PIIS"). Every 2 to 3 days, gas samples were collected using gas-tight syringes and analyzed in a gas chromatograph determining carbon dioxide (CO2) and methane (CH4) concentrations. An average gas concentration value between turnings was calculated and a two-way analysis of variance test was used to determine the significance of the differences between piles and pile location, followed by a Post Hoc Tukey test. During the thermophilic period, the mean CO2 concentration in PIC was 103 mL/L, 65 mL/L in PIT, and 24 mL/L in PIS, whereas, for PII, these values were 102mL/L, 59 mL/L, and 24 mL/L, respectively. The mean CH4 concentration between turnings in PIC was 9.2 mL/L, 1.9 mL/L in PIT, and 0.9 mL/L in PIS, whereas, for PII, the corresponding values were 6.4 mL/L, 0.4 mL/L, and 0.1 mL/L. For methane, there were no significant differences between these mean values, not only between the same placement in different piles, but also between different placements and different piles. This is probably due to the relatively frequent turnings (10 turnings during a period of 100 days), which did not allow the development of more anaerobic pockets in PI than in PII, indicating that both piles had similar greenhouse gas impacts. Results for carbon dioxide were similar in both piles, with some differentiation appearing between the core and top placements compared to the side placement. Reduction of the decomposition rate further from the core and a typical windrow chimney effect (gases from the core flowing through the top) explain this similarity between placements. The similarity between piles can be explained by the similar amounts of easily decomposable organic matter found in both piles, indicating that the effect of the bulking agent ratio on the concentration of gases within the pile was not significant.

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Studies of the average crystal structure properties of human dental apatite as a function of age in the range of 5-87 years are reported. The crystallinity of the dental hydroxyapatite decreases with the age. The a-lattice constant that is associated with the carbonate content in carbonate apatite decreases with age in a systematic way, whereas the c-lattice constant does not change significantly. Thermogravimetric measurements demonstrate an increase of the carbonate content with the age. FTIR spectroscopy reveals both B and A-type carbonate substitutions with the B-type greater than the A-type substitution by a factor up to ~5. An increase of the carbonate content as a function of age can be deduced from the ratio of the nu(2)CO(3) to the nu(1)PO(4) IR modes.

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BACKGROUND: Hygienic conditions in primary schools are a major concern for both governmental organizations and families. Particularly, the occurrence of faecal indicators on children's hands and various school surfaces has been associated with increased risk of diarrhoeal diseases. The presence of faecal streptococci on environmental surfaces and children's hands and the possible correlation with socio-economic factors were examined. METHODS: Overall, 1956 samples from hands and 1470 samples from surfaces were collected from 20 primary schools in Heraklion, Crete, Greece. RESULTS: Faecal streptococci were found at 52.9% of children's hands and at 16.7% of other surfaces. Children, who had parents with the highest education level (>12 years), had the lowest percentage (48.8%) of faecal contamination on their hands. Furthermore, boys exhibited higher levels of hands contamination compared with girls. Among the environmental surfaces examined, the school canteen reception was the most contaminated area. CONCLUSION: High faecal contamination was detected in primary schools in the examined region. Children's hands were highly infected (52.9%), while boys exhibited higher levels of contamination. The educational level of parents correlated well with the contamination of children's hands.

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AIMS: The aim of this study was to develop a novel strategy that permits the independent amplification of internal amplification control (IAC) and target sequence using the same set of primers, to improve the sensitivity of diagnostic PCR assays. METHODS AND RESULTS: The method described here is a Salmonella specific PCR test targeting the quorum sensing gene sdiA. It is based on a large size difference between the IAC and the target and consequently on their different extension time. The results indicate the enhanced sensitivity of this test when compared with the competitive IAC strategy. This is demonstrated through parallel testing of artificially contaminated human faecal samples. CONCLUSIONS: Utilizing this method, the concentration of the IAC, which often leads to false negative results if the target is present in extremely low concentration owing to competition, does not constitute a critical parameter for the detection limit of a PCR assay. SIGNIFICANCE AND IMPACT OF THE STUDY: To our knowledge, this is the first report of using extension time as a critical parameter for the sensitivity of a PCR test. A different approach for the construction of an IAC, based on inverse PCR, has also been introduced.

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An acetylene utilizing Gordona (Rhodococcus) bronchialis strain, screened for the production of fine chemicals, was found to be capable of producing small amounts of lysine. Attempts to produce amino-acid analog-resistant and/or sensitive mutants and auxotrophs of this strain with increased lysine production were made following UV-irradiation or N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) treatment. The bacterium exhibited surprisingly high resistance levels to the aforementioned mutagens which is attributed to highly effective inborn-repair systems. Natural resistance to high levels of S-(2-aminoethyl)-L-cysteine (AEC) (2%) was observed, in contrast with D, L-aspartic acid hydroxamate (AAH), L-lysine hydroxamate (LHX) and beta-fluoropyruvate (FP). A variety of amino-acid analog-resistant (AAHr, LHXr) or analog-sensitive (FPs) mutants were produced following UV-irradiation or MNNG treatment. Similarly, a large number of auxotrophs (68) of different types were also obtained. From these, one FPs mono-auxotroph and two poly-auxotrophs (with at least one requirement for the aspartic acid family) showed an increased lysine production (approximately 1.8 g/L) comparable (4 g/L) to that found in other bacteria capable of utilizing long-chain hydrocarbons (1).

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Recent progress in the understanding of the chromosomal rearrangements in Streptomyces has allowed us to envisage the possible involvement of genetic instability in the evolution of the chromosomal structure. The characterization of recombinational events in the terminal parts of the S ambofaciens chromosome, as well as the observation by other groups that linear plasmids and chromosomes are able to interact, would provide an explanation for the very high levels of polymorphism seen in the terminal inverted repeats of different strains of Streptomyces.

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Streptomyces ambofaciens DSM40697 possess six rRNA gene clusters which can be distinguished by probing BfrI-digested total DNA with the PCR-amplified l6S-23S ribosomal genet internal transcribed spacer. The six rrn loci of S. ambofaciens were cloned as recombinant cosmids and located on the AseI-Dral physical map of the linear chromosomal DNA. For five of the six ribosomal gene sets, the transcriptional orientation was determined relative to the physical map and was shown to be divergent away from an oriC-like locus.

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Adsorption reversibility and competition between fractionated components of the Trichoderma reesei cellulase system were studied. Specific endoglucanase (EGI), nonspecific endoglucanases (EGII, EGIII), and cellobio-hydrolase (CBHI) were previously grouped according to their hydrolytic function. At 5 degrees C, direct evidence of exchange between adsorbed and free enzyme was obtained for each component using [(3)H] and [(14)C] radiolabeled tracers. No release of bound enzymes was detected upon dilution of the free enzyme solution. In simultaneous adsorption of enzyme pairs, CBHI was shown to predominate adsorption. Endoglucanase EGI was preferentially adsorbed over EGII and EGIII. Sequential adsorption studies have shown that interaction between enzyme components largely determines the degree of their adsorption. Evidence suggests that both common and distinct adsorption sites exist and that their occupation depends on which components are involved. Predominance in adsorption by any one of the enzyme components is decreased at 50 degrees C. Light microscopy and monitoring of sugar production during cellulose hydrolysis provided evidence that reduction in the ionic strength decreases the adsorption predominance of CBHI and enhances the synergism between the cellulase components.