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Biomedical subjects

J M Gordon

Publications and source records attributed to J M Gordon.

At least 37 records · Page 2Linked to original sources
PubMed1988

Enzyme activity in crevicular fluid for detection and prediction of clinical attachment loss in patients with chronic adult periodontitis. Six month results.

Previous reports have described a method by which multiple constituents can be analyzed from a sample of gingival crevicular fluid (GCF) collected with a precut filter paper strip. In this study the relationship of changes in GCF levels of the vertebrate (lysosomal) enzymes beta-glucuronidase (BG) and arylsulfatase (AS) and the cytoplasmic enzyme lactate dehydrogenase (LDH) was evaluated longitudinally in reference to loss of clinical attachment in patients with existing chronic adult periodontitis. Thirty-six patients were followed for six months. Clinical attachment loss was recorded as the change between the baseline and three month examinations, and the three- and six-month examinations. GCF analysis was performed at baseline and three months. Three groups of patients were identified based on disease progression. Group I patients (N = 5) displayed a generalized form of disease activity. In these patients we observed clinical attachment loss of at least 2.0 mm at a minimum of three unrelated sites. Group II patients (N = 4) displayed a localized form of disease activity. In these patients clinical attachment loss of at least 2.5 mm occurred at one site, or two anatomically related sites. Group III patients (N = 27) did not display clinical attachment loss as defined here. Enzyme analysis was evaluated as a whole mouth score (the per cent of samples from a patient in which enzyme activity was at least twice the population mean) and at individual samples. Group I patients could be identified by elevated whole mouth scores for BG, while Group II patients could not be identified by whole mouth scores for any of the enzymes.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Lysosomal and cytoplasmic enzyme activity, crevicular fluid volume, and clinical parameters characterizing gingival sites with shallow to intermediate probing depths.

The biochemical analysis of gingival crevicular fluid (GCF) may offer a sensitive means of determining periodontal disease activity, including the transition of gingivitis to periodontitis. To continue our evaluation of the relationship between clinical and GCF parameters, 552 sites with shallow to intermediate (2.0-5.0 mm) probing depths (PD) were examined. The data were collected at baseline from 33 periodontitis patients participating in a longitudinal trial examining the relationship of changes in GCF biochemistry to attachment loss. Mesiobuccal sites were scored for dichotomous measures of bleeding on probing, gingival redness, suppuration, and plaque accumulation. In addition, GCF was collected using filter paper strips inserted into the sulcus for 30 seconds, eluted in buffer and assayed for activity of the enzymes beta-glucuronidase (BG), arylsulfatase (AS), and lactate dehydrogenase (LDH), markers for ground substance-degradation and cellular necrosis, respectively. Clinical and GCF parameters were evaluated by increasing PD. Plaque accumulation and bleeding on probing increased with increasing PD, although there was considerable overlap across groups. Suppuration was present in only a very small number of sites and the proportion of sites displaying gingival redness was not related to PD. GCF volume was grouped in 0.25-microliter increments, revealing a progressive shift with increasing PD toward a normal distribution around the median range of 0.51 to 0.75 microliter at 5.0 mm. Mean enzyme activities of BG, and to a lesser extent AS and LDH increased sharply from 2.0 to 3.0 mm, were relatively stable from 3.5 to 4.5 mm, and were significantly higher in 5.0 mm than 4.5 mm sites.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Enzyme activity in human gingival crevicular fluid: considerations in data reporting based on analysis of individual crevicular sites.

Using a reproducible approach to collection, processing and analysis of gingival crevicular fluid (GCF), this study examined 284 fluid samples from individual crevicular sites for the presence of the enzymes lactate dehydrogenase (LDH), B-glucuronidase (BG) and arylsulfatase (AS). 88 of the sites were from periodontally healthy individuals (probing depth 1-3 mm), while 98 sites from patients with periodontitis were examined before and 2 weeks after scaling and root planing (probing depths 1-3 mm, 4-6 mm and 7-10 mm). This study demonstrated the sensitivity of the enzyme assays. When GCF was collected with a 30-s insertion of the filter strip, 90% of the sites from the control subjects demonstrated LDH activity, 85% demonstrated BG activity and 73% demonstrated AS activity. For the 1-3 mm sites from the patients with periodontitis, 100% of sites from which fluid was collected demonstrated LDH and BG activity, and 90% of sites had AS activity before therapy. After therapy, 100% of sites demonstrated LDH activity, 90% had BG activity and 83% had AS activity. All sites in the 4-6 mm and 7-10 mm categories demonstrated activity of all 3 enzymes. The data were analyzed in terms of enzyme activity/30-s sample and as concentration of enzyme in a standard volume of GCF. Enzyme activity/30-s sample was a different and possibly more sensitive indicator of periodontal pathology than standard clinical parameters. There was a disassociation between clinical parameters and the data for enzyme analysis when it was reported as concentration.

Adult↗
PubMed1985

Evaluation and modification of spectrophotometric procedures for analysis of lactate dehydrogenase, beta-glucuronidase and arylsulphatase in human gingival crevicular fluid collected with filter-paper strips.

Filter-paper strips were used to collect GCF, and the sample eluted into a larger volume of diluent. This procedure allows for detection of site-to-site variation in GCF volume, and provides a 300-400 microliter sample for analysis of lactate dehydrogenase (LDH), beta-glucuronidase (BG) and arylsulphatase (AS) activities by a standard (serum) spectrophotometric assay modified for increased sensitivity. The results indicate that although the standard assay for LDH (based on oxidation of NADH) was adequate for detecting low activity in GCF samples, the modification doubled the sensitivity and allowed the use of less sample volume, thereby providing additional material for other assays. The standard assay for BG based on phenolphthalein being generated from phenophthalein glucuronic acid was not adequate for use in GCF analysis. The modification used increased assay sensitivity five-fold and allowed smaller samples to be used. The serum assay for AS (conversion of nitrocatechol sulphate to nitrocatechol) was accurate to the lower limit of AS activity in GCF and could be used without modification. The results emphasize the need to evaluate critically standard spectrophotometric assays for sensitivity when studying physiologically-collected GCF.

Adult↗
PubMed1985

Efficacy of Listerine antiseptic in inhibiting the development of plaque and gingivitis.

A 9-month double-blind controlled clinical study was conducted on adult subjects using either Listerine antiseptic, its vehicle control, or a water control in order to determine the efficacy of the antiseptic mouthrinse in inhibiting the development of plaque and gingivitis. Following screening examinations for minimal entry levels of plaque and gingivitis, all subjects received a complete prophylaxis. Subjects then continued their usual oral hygiene habits for a 3-week normalization period and were examined for soft tissue abnormalities and baseline measurements of plaque, gingivitis, and tooth stain. 2 additional prophylaxes were then performed, followed by a second baseline gingival examination. Zero plaque was re-established by rubber cup polishing and twice daily rinsing was begun. Soft tissue, plaque, gingivitis, and extrinsic tooth stain were evaluated after 1, 3, 6 and 9 months of rinsing with the randomly assigned mouthrinses. Results demonstrated that Listerine antiseptic significantly reduced the development of plaque at 1, 3, 6 and 9 months and the development of gingivitis at 9 months, as compared to its vehicle control or water control.

Adolescent↗
PubMed1985

Lactate dehydrogenase activity in gingival crevicular fluid collected with filter paper strips: analysis in subjects with non-inflamed and mildly inflamed gingiva.

A previous study of lactate dehydrogenase (LDH) in gingival crevicular fluid (GCF) suggested that the concentration is 10 to 25 times that of serum (means = 2300 international units/1 versus 100 IU/1 for serum). That study used capillary tubes to collect microliter amounts of GCF. Since invasive collection techniques can influence GCF flow, we evaluated LDH activity in GCF collected by filter strips. GCF was collected in a standardized fashion from 10 subjects with mild inflammation (GI = 0.5-1.0) and 10 subjects without evidence of gingival inflammation (GI = 0). Our results indicate that LDH volume activity was greater for subjects with GI = 0 (means = 105,529 IU/1) than for subjects with GI = 0.5-1.0 (means = 77,661 IU/1), but the difference was not significant. LDH total unit activity was significantly greater in subjects with GI = 0.5-1.0 versus GI = 0 (means = 0.048 IU versus means = 0.0242 IU, P less than 0.0001). The relationship of LDH volume activity to GCF volume, the regression lines fit to the data, and calculation of LDH total unit activity were important for analysis of enzyme activity in GCF.

Adolescent↗
PubMed1985

Antibiotic susceptibilities of periodontal bacteria. In vitro susceptibilities to eight antimicrobial agents.

In vitro susceptibilities of 369 to 966 bacterial isolates from periodontal lesions to eight antibiotics were determined by agar dilution technique as a means of determining which antimicrobial agents were inhibitory for bacteria frequently associated with destructive periodontal diseases. Although most bacteria were relatively susceptible to the penicillins, greater activity was generally noted with amoxicillin than with either penicillin or ampicillin with the exception of Selenomonas sputigena and Peptostreptococcus. Antibacterial activities obtained with minocycline were significantly higher than with tetracycline for Actinobacillus actinomycetemcomitans and Streptococcus but comparable for most other taxa. Clindamycin and metronidazole both demonstrated excellent activity against the anaerobic Gram-negative rods but were less effective against some of the capnophilic and facultative organisms. Eikenella corrodens was exceptionally resistant to both of these drugs; and A. actinomycetemcomitans was generally resistant to clindamycin but relatively susceptible to metronidazole. Erythromycin was considerably less active than the other antibiotics against the majority of the periodontal bacteria. No single antibiotic, at concentrations equivalent to those achieved in body fluids, was uniformly effective in inhibiting all bacteria currently implicated or suspected as etiologic agents of periodontal diseases.

Actinobacillus↗
PubMed1985

Lactate dehydrogenase, beta-glucuronidase and arylsulfatase activity in gingival crevicular fluid associated with experimental gingivitis in man.

Experimental gingivitis provides a useful model for studying the initiation of periodontal disease in man. This study evaluated over a 4-week period the Plaque Index (PLI), Gingival Bleeding Time Index (GBTI), and gingival crevicular fluid (GCF) for resting and flow volume as well as the concentration and total activity of three enzymes in the GCF (lactate dehydrogenase--LDH, beta-glucuronidase--BG and arylsulfatase--AS) from the maxillary right quadrant of eight subjects with healthy gingiva. After rising sharply during the 1st week, the PLI continued to increase during the 2nd week but remained constant during the 3rd and 4th weeks. The GBTI, and the resting and flow GCF volumes, increased steadily throughout the study. LDH concentration in GCF varied minimally during the experiment, while total LDH activity rose slightly over the 4-week period. BG concentration and total activity in GCF rose steadily from baseline to the 3rd week and then either fell or leveled off during the 4th week. AS concentration in GCF rose from baseline to the 2nd or 3rd week and then fell. AS total activity in GCF rose from baseline to the 2nd week and then remained constant. These data suggest that while clinical signs of inflammation increased over the 4 weeks of the experiment, a homeostatic mechanism in the crevicular environment may control ground substance-degrading enzyme activity during experimental gingivitis in man.

Adult↗
PubMed1984

Arylsulphatase activity in human gingival crevicular fluid.

Arylsulphatase activity in fluid collected from non-inflamed (n = 5), gingivitis (n = 5) and periodontitis (n = 5) subjects was assayed. The mean volume activity for each group was: non-inflamed = 768 +/- 165 nm/ml per h; gingivitis = 2431 +/- 1118 nm/ml per h; periodontitis = 2860 +/- 1839 nm/ml per h. The mean total unit activity for each group was: non-inflamed = 0.326 +/- 0.076 nm; gingivitis = 1.394 +/- 0.411 nm; and periodontitis = 3.571 +/- 1.700 nm. Analysis of fluid from isolated sites in periodontitis suggests that reporting total unit activity (absolute amount of enzyme activity) is more meaningful than reporting volume activity (enzyme concentration) for arylsulphatase activity.

Arylsulfatases↗
PubMed1983

Antibiotic susceptibility testing of subgingival plaque samples.

The in vitro inhibitory effect of several antimicrobial agents was determined against dispensed dental plaque samples taken from periodontally diseased sites as an aid in the selection of antibiotics for adjunctive use in periodontal therapy. 2 groups of patients were sampled. 1 group of 10 patients with severely advanced disease had received periodontal treatment which included the frequent adjunctive use of an antibiotic. The second group consisted of 15 individuals with less severe periodontal disease; only 4 individuals had been previously treated with antibiotics for their periodontal disease. Bacterial samples of subgingival plaque were taken from each patient and tested against a battery of antibiotics to determine which agent was the most effective in suppressing bacterial growth. Each antibiotic was incorporated into Trypticase-soy blood agar at a concentration equivalent to that achieved in either gingival fluid or blood following recommended oral dosages. The inhibitory effect was determined by comparing the number of bacterial recovered on the antibiotic-containing medium to the total number of bacteria recovered on the basal medium. Penicillins, with the exception of cloxacillin, were the most effective in inhibiting bacterial growth. Benzylpenicillin consistently inhibited the growth of 90% of the isolates recovered on media free of antibiotics while ampicillin and amoxicillin frequently inhibited 99% or more of the bacteria recovered. Tetracycline was generally inhibitory for at least 90% of the isolates if the patients had not been previously treated with this agent. However, resistance to this drug was common in samples taken from patients previously treated with tetracycline. Doxycycline, a tetracycline derivative, did not inhibit significantly more isolates than tetracycline. Clindamycin was inhibitory for 90% or more of the organisms in most of the samples; and, was usually effective in inhibiting isolates in samples which exhibited large numbers of isolates resistant to tetracycline. Erythromycin was relatively ineffective against the isolates recovered from samples from the severely diseased group but was inhibitory to isolates in some samples taken from the more moderately diseased group. Metronidazole, at the concentration tested, was largely ineffective against the isolates in bacterial samples from both groups. No single antimicrobial agent was found to be inhibitory for greater than 90% of the bacteria recovered from all of the subgingival plaque samples with the possible exception of some penicillins.

Adolescent↗
PubMed1981

Concentration of tetracycline in human gingival fluid after single doses.

The concentration of tetracycline in gingival fluid was measured following the oral administration of single doses of 250 or 500 mg. Six volunteers received a single dose of either 250 mg or 500 mg of tetracycline and gingival fluid was sampled at 15-min intervals during the first 2 h, 30-min intervals for the following 2 h and at hours 5, 6 and 7. Four volunteers were given a single dose of either 250 mg or 500 mg and were sampled every hour for 24 h. Gingival fluid was sampled using an intracrevicular technique from four gingival sites and blood was obtained by finger puncture. The concentration of tetracycline in gingival fluid peaked at 3 1/2-7 h achieving average levels typically in the range of 5-12 micrograms/ml. Blood levels peaked at 3-4 h and reached values between 1.0 to 2.6 micrograms/ml. Tetracycline was detectable in gingival fluid at least 19 h after a single dose but rarely was detectable at 24 h. The results demonstrated that tetracycline in the gingival fluid was typically 2-10 times blood levels after a single dose.

Gingival Crevicular Fluid↗
PubMed1981

Gingival crevicular fluid levels of clindamycin compared with its minimal inhibitory concentrations for periodontal bacteria.

Clindamycin concentrations in gingival crevicular fluid and in blood were determined over a 7-h period and were related to the minimal inhibitory concentrations of this agent for 340 bacterial strains isolated from diseased periodontal sites. The clindamycin levels after administration of single 300-mg oral doses were measured in gingival crevicular fluids by using an agar diffusion bioassay. Minimal inhibitory concentrations were determined by agar dilution techniques for 30 species of periodontal bacteria. With the exception of Eikenella corrodens and Actinobacillus actinomycetemcomitans, most of the bacteria were inhibited by a concentration of 1.0 microgram of clindamycin per ml or less. The peak concentrations in crevicular fluid (2.0 +/- 0.3 microgram/ml) and in blood (1.9 +/- 0.3 micrograms/ml) were approximately the same. However, crevicular fluid levels of 1.0 micrograms/ml and above were present for up to 6 h, whereas blood concentrations dropped below 1.0 micrograms/ml within 2 h after administration. Based on its minimal inhibitory concentrations, clindamycin at crevicular fluid levels of 1.0 micrograms/ml or above should inhibit most bacteria associated with diseased periodontal sites.

Bacteria↗
PubMed1981

Tetracycline: levels achievable in gingival crevice fluid and in vitro effect on subgingival organisms. Part I. Concentrations in crevicular fluid after repeated doses.

The concentration of tetracycline in gingival crevice fluid and blood was determined using a sensitive bioassay after oral administration of repeated doses of tetracycline. Crevicular fluid was sampled by an intracrevicular technique from four gingival sites in each individual and blood was obtained by finger puncture. Four volunteers received doses of 250 mg of tetracycline-HCl either every 6 hours or every 12 hours and were sampled at hours 0 to 15, 21 to 36, 48 to 60 and 96 to 102. Volunteers given 250 mg every 6 hours had average crevicular fluid concentrations between 4 to 8 micrograms/ml and blood concentrations between 2 to 2.5 micrograms/ml after 48 hours. The levels in crevicular fluid and blood of volunteers who received 250 mg every 12 hours were 2 to 4 micrograms/ml and 0.3 to 1.4 micrograms/ml respectively after 48 hours. The results demonstrated that after repeated doses of tetracycline the crevicular fluid levels were typically 2 to 4 times the blood levels.

Administration, Oral↗
PubMed1981

Tetracycline: levels of achievable in gingival crevice fluid and in vitro effect on subgingival organisms. Part II. Susceptibilities of periodontal bacteria.

The sensitivity to tetracycline of 345 bacterial isolates from periodontal lesions was determined. Most species of bacteria, including those thought to be involved in the initiation and progress of destructive periodontal disease, were inhibited in vitro by tetracycline concentrations of 4 to 8 micrograms/ml. This concentration is equivalent to crevicular fluid levels of tetracycline at dosages of 1 gm/day. These data indicate that tetracycline is inhibitory at levels achieved in crevicular fluid for bacteria currently implicated in destructive periodontal disease.

Bacteria↗
PubMed1980

Collagenase in human cornea: immunologic localization.

Collagenase has been localized in human corneas using immunocytochemical techniques employing a specific antiserum to human skin collagenase. The enzyme was found in vivo in ulcerating corneas, whereas in corneas obtained from a variety of nonulcerative conditions, no immunologic evidence of the enzyme was seen. Corneal collagenase was present only in the stromal portion of the cornea, suggesting that cells from this tissue are the source of the enzyme. The localization of collagenase to the corneal stroma was reproduced by placing either ulcerating or nonulcerating corneas in tissue culture, indicating that the organ culture system may represent a model that duplicates some conditions present in corneal disease.

Adult↗
PubMed1980

Sensitive assay for measuring tetracycline levels in gingival crevice fluid.

An increased interest in the clinical use of antibiotics as an adjunct to periodontal therapy has created a need to determine antibiotic concentrations in fluid obtained from the gingival crevice. For this purpose, an increase in sensitivity beyond that possible with current tetracycline assays is essential because sample volumes of gingival fluid typically obtained are less than 0.5 microliter. This report describes the development of an agar-diffusion assay technique capable of measuring the concentration of tetracycline in samples of gingival crevice fluid in the range of 0.1 to 4.0 microgram/ml. The assay will detect amounts of tetracycline in gingival crevice fluid samples as low as 50 pg. The high sensitivity of this assay was achieved by optimizing the medium depth, inoculum density, agar concentration, pH, period of prediffusion, and selection of basal medium. Use of this assay indicated that the concentration of tetracylcine in gingival crevice fluid was greater than that found in blood and persisted at elevated levels for longer periods.

Biological Assay↗
PubMed1979

The Brompton mixture versus morphine solution given orally: effects on pain.

The Brompton mixture is widely used as an effective method for controlling pain in cancer patients. In a double-blind crossover trial a standard Brompton mixture containing morphine, cocaine, ethyl alcohol, syrup BP and chloroform water was compared with morphine alone in a flavoured aqueous solution; both were administered orally. Pain was measured by means of the pain intensity index of the McGill Pain Questionnaire. Ratings of confusion, nausea and drowsiness were obtained from both the patients and their nurses and relatives. The data showed that there was no significant difference between the Brompton mixture and morphine administered orally for any of the variables. Both relieved pain effectively in about 85% of the patients.

Administration, Oral↗