Publications by authors named "P J Macuch"

53 Publications

The development of cement and concrete additive: based on xylonic acid derived via bioconversion of xylose.

Appl Biochem Biotechnol 2006 Mar;131(1-3):645-58

Grace Performance Chemicals, W.R. Grace & Co., 62 Whittemore Avenue, Cambridge, MA 02140, USA.

The present work attempted to utilize xylose by converting it to an aldonic acid. In the present study, xylose was converted to xyloni acid by using commercial glucose oxidase enzyme, palladium catalysis, and microbial bioconversion. The enzyme conversion was successfully done using a commercial glucose oxidase. The microbial conversion with Gluconobactor oxydans proceeded even with the presence of a large amount of lignosulfonate. Thus obtained xylonic acid products were evaluated as a cement dispersing agent in cement and concrete tests. It was found that xylonic acid is approximately twice as effective as lignosulfonate. Xylonic acid can be effectively utilized in concrete water reducer application.
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http://dx.doi.org/10.1385/ABAB:131:1:645DOI Listing
March 2006

The development of cement and concrete additive: based on xylonic acid derived via bioconversion of xylose.

Appl Biochem Biotechnol 2006 ;129-132:645-58

Grace Performance Chemicals, W.R. Grace & Co., 62 Whittemore Avenue, Cambridge, MA 02140, USA.

The present work attempted to utilize xylose by converting it to an aldonic acid. In the present study, xylose was converted to xylonic acid by using commercial glucose oxidase enzyme, palladium catalysis, and microbial bioconversion. The enzyme conversion was successfully done using a commercial glucose oxidase. The microbial conversion with Gluconobactor oxydans proceeded even with the presence of a large amount of lignosulfonate. Thus obtained xylonic acid products were evaluated as a cement dispersing agent in cement and concrete tests. It was found that xylonic acid is approximately twice as effective as lignosulfonate. Xylonic acid can be effectively utilized in concrete water reducer application.
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September 2006

Optical sensors for detection of bacteria. 1. General concepts and initial development.

Anal Chem 2001 Feb;73(3):462-6

Echo Technologies, Inc. and Altran Corporation, Boston, MA 02210, USA.

The concept of using immobilized nucleic acid stains as detection chemistry to fabricate optical bacterial sensors is first demonstrated. SYTO 13 (a green fluorescent cell stain) is used as the molecular recognition element and fluorescent reporter in the sensor. The sensor responds to aqueous and aerosolized bacterial samples in 15 and 30 min, respectively. In addition, the sensor can discriminate a change in Pseudomonas aeruginosa (Pa) cell concentration of 1 order of magnitude or less and can detect down to 2.4 x 10(5) cells/mL of Pa cells. The utility of the sensor is demonstrated by monitoring the growth of a Pa cell culture over a period of 50 h.
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http://dx.doi.org/10.1021/ac000459bDOI Listing
February 2001

Serum IgG reactivity to subgingival bacteria in initial periodontitis, gingivitis and healthy subjects.

J Clin Periodontol 2000 Jul;27(7):473-80

The Forsyth Institute, Boston, Massachusetts 02115, USA.

Background/aims: Established periodontal diseases may be associated with antibody responses to periodontal pathogens, but it is not known at which stage of disease this antibody response is initiated. This study aimed to characterize the host systemic response in initial periodontitis, gingivitis, and periodontal health, to evaluate whether elevated serum antibodies to subgingival species could be detected in initial periodontitis.

Method: Human systemic immune response were evaluated to 40 subgingival bacterial species in 16 healthy, 21 gingivitis, 11 initial periodontitis and 5 progressing recession adults. Subjects had minimal periodontal attachment level (AL) loss at baseline. Disease categories were determined after 12 months monitoring at three-month intervals. Increased AL loss > or = 1.5 mm (disease activity) at interproximal sites defined initial periodontitis, recession was characterized by AL loss at buccal sites. Serum IgG antibodies were evaluated semi-quantitatively by immunoblot from blood taken at baseline, active and final visits.

Results: No antibody was detected from 55% of reactions. When detected, levels were below those reported for advanced periodontitis subjects. There were no major differences in serum antibody levels between healthy, gingivitis and initial periodontitis subjects, despite differences in the subgingival microbiota. Serum antibodies for more species were detected in recession subjects, compared with the other study subjects. No changes in antibody levels were detected between baseline, active, and final visits. No systematic association between species colonization and presence of systemic antibody was observed.

Conclusions: This study did not detect differential elevation of mean serum antibody levels in initial periodontitis subjects, suggesting that serum antibody levels are not sensitive risk markers for initial periodontitis.
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http://dx.doi.org/10.1034/j.1600-051x.2000.027007473.xDOI Listing
July 2000

Campylobacter species in health, gingivitis, and periodontitis.

J Dent Res 2000 Feb;79(2):785-92

Altran Corporation, Boston, MA, USA.

At least seven Campylobacter species have been identified from subgingival sites. Campylobacter rectus has been implicated as a periodontal pathogen; however, association with periodontal infections of other Campylobacter species, especially the newly described Campylobacter showae, is unclear. This study examined which Campylobacter species were associated with periodontal health and disease. Subgingival Campylobacter species from initial and established periodontitis were compared with species from periodontally healthy subjects, including subjects with gingivitis. Campylobacter species were isolated on selective media and identified by whole-cell protein profiles (SDS-PAGE). Except for C. rectus, Campylobacter levels were frequently below the detection limit (2-5% of the microbiota) of non-selective culture methods. C. rectus and C. showae, including Campylobacter X, were found more frequently and in higher levels from diseased than from healthy periodontal sites. C. gracilis was the dominant Campylobacter species found in relatively shallow pockets; however, its presence was unrelated to periodontal health or disease. C. concisus was isolated in higher proportions from relatively shallow and healthy sites, compared with deeper pockets. C. curvus was unrelated to periodontal health or disease. Analysis of the study data confirmed the relationship of C. rectus with diseased subgingival sites and indicated that C. showae may also be associated with periodontal disease.
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http://dx.doi.org/10.1177/00220345000790021301DOI Listing
February 2000
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