Periodontal findings in elderly patients with non-insulin dependent diabetes mellitus

The periodontal status of 25 patients with non-insulin dependent diabetes mellitus (NIDDM) (age range 58 to 76) was investigated and compared with 40 non-diabetic control subjects (age range 59 to 77). Surfaces with visible plaque and bleeding after probing, calculus, recessions, and pathological pockets were examined. The total attachment loss was calculated as a sum of recessions and pockets in millimeters. Mesial and distal bone loss was measured from panoramic radiographs and mean alveolar bone loss was calculated. Periodontal disease was considered advanced when mean alveolar bone loss was over 50%, or 2 or more teeth had pockets > or = 6 mm. Microbiological analysis comprised the detection of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Bacteroides forsythus by a polymerase chain reaction (PCR) method. Patients with NIDDM had significantly more often advanced periodontitis than control subjects, 40.0% and 12.5%, respectively. Diabetic patients did not harbor more pathogens than the control subjects. The HbA1C level deteriorated in patients with advanced periodontitis, but not in other patients with NIDDM, when compared to the situation 2 to 3 years earlier. Advanced periodontitis seems to be associated with the impairment of the metabolic control in patients with NIDDM, and a regular periodontal surveillance is therefore necessary.     

Differential diagnosis of Staphylococcus aureus from Staphylococcus epidermidis and Staphylococcus saprophyticus by alphazurine A dye

Staphylococcal bacterial suspensions were streaked on Trypticase soy agar with 5% sheep blood culture plates. Paper discs containing alphazurine A, a triphenylmethane dye, were placed on the inoculated plates which were incubated at 37 degrees C for 24 hours. A wide zone of inhibition of growth of Staphylococcus aureus was present around the paper discs. Growth of Staphylococcus epidermidis and Staphylococcus saprophyticus was not inhibited.     

Overdose among youth in Bahrain: psycho-social characteristics, contact with helping agencies and problems

The in vitro minimal inhibitory concentrations (MIC) and minimal bactericidal concentration (MBC) of roxithromycin and erythromycin against Actinobacillus actinomycetemcomitans were evaluated. Sixty-seven different A. actinomycetemcomitans isolated from periodontal pockets of 101 subjects with different forms of early-onset and adult periodontitis and three reference strains of A. actinomycetemcomitans (ATCC 29522, ATCC 29523, and NCTC 9710) were included in this study. Erythromycin showed poor in vitro activity against A. actinomycetemcomitans; roxithromycin, on the contrary, exhibited good in vitro activity. Moreover, roxithromycin showed the best in vitro antimicrobial activity against 17 serotype a and 12 serotype c subpopulations of A. actinomycetemcomitans; against 38 serotype b subpopulation of A. actinomycetemcomitans, roxithromycin was consistently active. Roxithromycin exhibited MBC values usually equal to, or one-fold higher than MIC values. All the MBC values of erythromycin were three- to four-fold higher than the respective MIC result. Since roxithromycin is characterized by high concentrations in serum and good penetration and diffusion into gingival tissue, it could be expected to pass into the gingival crevicular fluid at levels sufficiently high to inhibit A. actinomycetemcomitans in vivo. These data indicate that roxithromycin might be a potential candidate for therapeutic trials in patients with A. actinomycetemcomitans-associated periodontitis.     

Molecular lipophilicity potential by CLIP, a reliable tool for the description of the 3D distribution of lipophilicity: application to 3-phenyloxazolidin-2-one, a prototype series of reversible MAOA inhibitors

Six methods were compared for detection of three strains of Escherichia coli O157:H7 in enrichments of inoculated apple juice. Juice was inoculated at levels varying from 0.1 to 100 CFU/ml and centrifuged after overnight storage at 4 degrees C, and pellets were incubated at 37 degrees C in nonselective enrichment broth. At hourly intervals between 5 and 10 h and at 24 h, the enrichments were tested for E. coli O157:H7 by direct fluorescent antibody (DFA), antibody-direct epifluorescent filter technique (Ab-DEFT), direct selective plating on sorbitol MacConkey agar (SMA), immunomagnetic separation coupled to either selective plating (IMS-SMA) or the polymerase chain reaction (IMS-PCR), and flow cytometry (FC). The most consistent detection of 0.1 CFU/ml of the slowest growing strain of the pathogen was provided by the IMS-SMA and IMS-PCR after 8 h of enrichment. The time required for detection at the level of 0.1 CFU/ml for each assay was Ab-DEFT, 11 h; IMS-PCR, 16 h; FC, 24 h; IMS-SMA, 32 h; and SMA, 48 h. Absolute detection limits (without enrichment) were: IMS-PCR, 10(3) CFU/ml; Ab-DEFT and IMS-SMA, 10(4) CFU/ml; SMA, 10(5) CFU/ml; and DFA, 10(6) CFU/ml. Recovery of the pathogen (10 CFU/ml) in apple juice after 28 days of 4 degrees C storage was possible by means of an 8-h enrichment and Ab-DEFT, IMS-PCR, or IMS-SMA.     

Thermal inactivation of Mycobacterium paratuberculosis in milk

Thermal inactivation of Mycobacterium paratuberculosis, a suspected human pathogen, was determined in ultrahigh-temperature whole milk. Three strains of M. paratuberculosis were examined for survival at temperatures from 55 to 75 degrees C using a submerged glass capillary tube method. Clumped and declumped suspensions of the cultures were used to determine the rate of heat inactivation and survival at pasteurization temperatures. Methods for declumping M. paratuberculosis included the use of glass beads, vortexing, and passing the cells through a 26-gauge needle. The latter procedure was found to be superior over other methods and did not affect the viability of cells. Capillary tubes filled with milk containing 4 x 10(6) to 3 x 10(7) CFU/ml were heated at temperatures ranging from 55 to 75 degrees C. At 55 degrees C, minimal thermal inactivation was observed for clumped and declumped cells. At 58 degrees C, thermal inactivation ranging from 0.3 to 0.7 log reduction was observed for both clumped and declumped suspensions. D values at 60 degrees C ranged from 8.6 to 11 min and 8.2 to 14.1 min for clumped and declumped cells, respectively. At 63 degrees C, the D values ranged from 2.7 to 2.9 and 1.6 to 2.5 min for clumped and declumped cells, respectively. Survival of M. paratuberculosis at initial levels ranging from 44 to 10(5) CFU/ml at pasteurization treatment (63 degrees C for 30 min and 72 degrees C for 15 s) was also determined. No survivors were observed after incubating plates for up to 4 months on Middlebrook 7H11 agar and up to 2 months on Herrold's egg yolk medium. The sensitivity of the plating method was 1 CFU/250 microliters. These results demonstrate that low levels of M. paratuberculosis, as might be found in raw milk, will not survive pasteurization treatments.     

Diagnostic utility of specific microbiological markers for periodontal diseases

Specific detection of marker organisms Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans with an immunoassay provided 2 types of useful information directly into private clinical practice: 1) persistence of P. gingivalis in patients undergoing regular treatment allowed rapid identification of pockets requiring further treatment without waiting for measurable progression of lesions and 2) presence of A. actinomycetemcomitans in adults at any stage of diagnosis or treatment identified patients who may prove to have difficult-to-manage periodontitis. We made these findings in 253 patients (234 in specialist periodontal practices [F-ME 55; MHM 179] and 19 in general dental practice [EWM]). The search for useful diagnostic markers overlaps only partly with the search for periodontal pathogens. The P. gingivalis marker and the A. actinomycetemcomitans marker identify 2 different patterns of infection that appear to reflect 2 different underlying problems. Demonstration of pocket-dependent infection with P. gingivalis in treated patients provides an outcome marker for sites not converting to marker-negative sites at detection levels of the immunoassay. This information facilitates selection of sites and patients requiring adjustment of treatment regimens. Detection of A. actinomycetemcomitans in adult patients is significantly associated with periodontitis characterized as refractory. Positive identification of A. actinomycetemcomitans with the immunoassay supports clinical decision-making by drawing attention to adult patients who require closer monitoring and intensive persistent treatment. Successful application of immunoassay detection of microbiological markers is based on continuous patient monitoring to support clinical decisions; it does not replace careful clinical judgment.     

Reduced serum IgG reactivities with bacteria from dental plaque in HIV-infected persons with periodontitis

Serum samples were obtained from 44 HIV-seropositive (HIV+) and 37 HIV-seronegative (HIV-) persons that were grouped according to periodontal status. Serum IgG and IgA reactivities towards Streptococcus mutans, Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis. Prevotella intermedia, Prevotella nigrescens and Fusobacterium nucleatum were measured by means of ELISA. HIV+ persons with chronic marginal periodontitis showed significantly lower IgG reactivities to the periodontal pathogens A. actinomycetemcomitans, P. gingivalis, P. intermedia and F. nucleatum as compared with their HIV- counterparts (p < 0.05). Specific serum IgA reactivities were similar in the two periodontitis groups, except for P. nigrescens where the HIV+ group with chronic marginal periodontitis had lower values than their systemically healthy counterparts (p < 0.05). The results indicate that HIV infection affects the humoral serum immune responses against bacteria in dental plaque; the depressed antibody responses may contribute to the increased susceptibility for periodontal infections in HIV-infected patients.     

Serum antibodies to Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in juvenile periodontitis and adult periodontitis (part I)

Recent microbiological studies support the concept that specific gram negative bacteria play a major role in the etiology and pathogenesis of human chronic inflammatory periodontal disease. Actinobacillus actinomycetemcomitans has been isolated frequently from juvenile periodontitis and Porphyromonas gingivalis has been shown to be a prominent species in adult periodontitis in humans. The purpose of this study was to determine levels of the specific antibodies to A.actinomycetemcomitans and P.gingivalis in 17 patients with juvenile and 15 patients with adult periodontitis and 24 healthy subjects. IgG and IgM antibody titers against these antigens were determined by enzyme-linked immunosorbent assay (ELISA). The levels of antibodies against A.actinomycetemcomitans were significantly higher in the juvenile periodontitis compared to the adult periodontitis patients and controls. Anti-P.gingivalis antibodies were elevated in adult periodontitis compared to juvenile periodontitis patients and controls.     

Human immunodeficiency virus disease: changing patterns of intraocular inflammation

Oral malodor affects a large proportion of the population and may be the cause of a significant social and psychological handicap. This pilot study aimed to examine whether a 1-stage full-mouth disinfection in periodontitis patients (scaling and root planing of all pockets within 24 hours together with the application of chlorhexidine to all intra-oral niches followed by chlorhexidine mouth rinsing for 2 months) resulted in a significant improvement in malodor when compared to a fractionated periodontal therapy (consecutive root planings per quadrant, at a 1 to 2 week interval). The baseline and outcome data concerning oral malodor were linked to the presence of tongue coating and to its roughness (fissures). Twenty-four patients with severe periodontitis were randomly allocated to test and control groups. At baseline and after 1 and 2 months, the concentration of volatile sulfur compounds (VSC) in the mouth was measured and organoleptic ratings (expired air and total mouth air) were given. Plaque samples were collected from the dorsum of the tongue to calculate the number of colony forming units (CFU) per ml (anaerobic culturing) as well as the number of pigmented CFU/ml. Both the baseline organoleptic ratings and the VSC scores correlated well with the presence of tongue coating but not with the tongue roughness. Because a correlation between tongue coating and its microbial load could not be detected, it was hypothesized that the tongue coating per se, and not the bacteria, might be responsible for the malodor. The 1-stage full-mouth disinfection resulted in a faster and additional reduction in the organoleptic ratings of the oral malodor, even after 2 months. This might be explained by the improved periodontal outcome and/or the more significant reduction in the CFU/ml of pigmented species. In contrast to the organoleptic ratings, which were significantly reduced in both treatment groups (when compared to baseline), the VSC levels remained unchanged. This pilot study indicates that a 1-stage full-mouth disinfection has, in comparison to a standard periodontal therapy, additional beneficial effects in the treatment of oral malodor.     

Infusion therapy with milrinone in the home care setting for patients who have advanced heart failure

The pathogenicity of 14 isolates identified as Prevotella intermedia or Prevotella nigrescens by serogrouping using monoclonal antibodies was compared in a tissue cage model in rabbits. Seven strains from periodontal abscesses, 5 strains from deep periodontal pockets and 2 strains from gingivitis were tested in the animal model comprising 6 Teflon tissue cages implanted on the back each of 34 rabbits. A total of 10(5)-10(8) cells of P. intermedia or P. nigrescens strains were inoculated alone or together with either Actinobacillus actinomycetemcomitans or Streptococcus mitis. Five strains of Porphyromonas gingivalis were used as a reference. The infectivity was recorded as pus formation and log viable count in aspirated material for 3, 7 and 14 days. None of the Prevotella strains inoculated in monoculture survived more than 3 days, and they had no capacity to produce abscess. P. intermedia or P. nigrescens strains in combination with A. actinomycetemcomitans produced abscesses in 33-100% and with S. mitis in 42-100%. No difference in abscess formation or log viable count in samples after 14 days was recorded between serogroup I (P. intermedia) and serogroup II and III (P. nigrescens). The infectivity of P. intermedia or P. nigresceas strains did not differ whether they were isolated from periodontal abscess, periodontal pocket or gingivitis. P. intermedia and P. nigrescens strains produced abscesses in combination with a facultative anaerobic strain and appears to have a similar pathogenicity in the wound chamber model in rabbits.     

Epidemiology and transmission of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans among children and their family members. A report of 4 surveys

The distribution and transmission of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans in 4 families were studied. The families were included, based on the isolation of P. gingivalis from a young child or adolescent. The probands of these 4 families were: a 5-year old periodontally healthy boy; a 17-year old girl with severe generalized juvenile periodontitis; an 11-year old girl with prepubertal periodontitis; 2 sisters, 5 and 17-years old, with untreated severe periodontitis as a component of the Papillon-Lefèvre syndrome. All members of the 4 families were examined clinically and microbiologically for the presence of P. gingivalis and A. actinomycetemcomitans. Most of the parents appeared to be adult periodontitis patients; the parents of one proband were edentulous. Results showed that in all cases at least one of the parents was positive for P. gingivalis. On the basis of indistinguishable restriction endonuclease patterns (REPs) of P. gingivalis and A. actinomycetemcomitans isolates from parents and their children, and distinct REPs from unrelated individuals, the present study indicates that P. gingivalis and A. actinomycetemcomitans were transmitted between parents and their children.     

The prevalence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Bacteroides forsythus in humans 1 year after 4 randomized treatment modalities

The relationship between probing attachment changes in treated periodontal pockets and the prevalence of selected periodontal pathogens was assessed in 10 patients with adult periodontitis 1 year following randomized therapy. All patients had at least 1 tooth in each quadrant with an inflamed pocket of probing depth > or =5 mm and clinical attachment loss and harbored at least one of the following 3 major periodontal pathogens: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, or Bacteroides forsythus. The number of target organisms per site was determined preoperatively; at 1 week; and at 1, 3, 6, and 12 months postoperatively utilizing DNA probes. The following clinical parameters were measured and recorded preoperatively and at 1, 3, 6, and 12 months post-treatment: gingival fluid flow, gingival index, plaque index, probing depth, probing attachment level, gingival recession, and bleeding on probing. One quadrant in each patient was randomly assigned to 1 of the following 4 treatments: 1) scaling and root planing; 2) pocket reduction through osseous surgery and apically-positioned flap; 3) modified Widman flap; and 4) modified Widman flap and topical application of saturated citric acid at pH 1 for 3 minutes. All 4 treatments were rendered in one appointment using local anesthesia. No postoperative antibiotics were used, but patients rinsed with 0.12% chlorhexidine for the first 3 months postoperatively and received a prophylaxis every 3 months. This investigation revealed: 1) 30.0% of the sites were infected by at least 1 species at 3, 6, and 12 months postoperatively. 2) Failing sites were infected by a high number of both Pg and Bf These sites had a mean of 24.2+/-9.0 x 10(3) Pg and 93.1+/-42.0 X 10(3) Bf while stable sites had a mean of 6.8+/-0.5 x 10(3) Pg and 7.2+/-1.2 x 10(3) Bf (P = 0.06 and P = 0.05, respectively). 3) The infected sites lost significantly more mean clinical attachment at 12 months (1.5+/-0.5 mm compared to a loss of 0.2+/-0.3 mm for uninfected sites, P = 0.017). 4) The infected sites had a significantly greater BOP (67+/-14% versus 25+/-8% for uninfected sites at 12 months, P = 0.012). 5) The choice of treatment modality did not affect the prevalence of the target species at 1 year post-treatment. These results suggest that prevalence of microbial pathogens negatively affects the 1 year outcome of periodontal surgical and nonsurgical therapy.     

Repopulation of periodontal pockets by microbial pathogens in the absence of supportive therapy

This clinical study evaluated the reinfection incidence by Actinobacillus actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and Prevotella intermedia (Pi) in periodontal pockets following scaling and root planing (SRP) and intra-pocket irrigation with antimicrobial agents in a patient population who did not receive supportive maintenance therapy. The number of target organisms was determined utilizing DNA probes. Forty-one (41) inflamed pockets > or = 5 mm with attachment loss and containing at least one target species were selected in 6 adult patients. Following a baseline clinical and bacterial examination, all patients received thorough SRP. In addition, 1 to 2 teeth in each patient were randomly assigned to each of the following 4 treatment modalities: 1) control group, no irrigation; 2) saline group, irrigation with 2 cc of 0.85% saline; 3) tetracycline group, irrigation with 2 cc of aqueous tetracycline HCl, 50 mg/ml (5%); and 4) chlorhexidine group, irrigation with 2 cc, respectively. All selected sites were non-adjacent. No additional therapy was rendered during the entire 1-year observation period. Clinical parameters and microbial analyses were recorded again at 1 week, and 1, 3, 6, 9, and 12 months post-treatment. The effect of antimicrobial irrigation on the reinfection rate of sites by Aa, Pg, and Pi was compared with that of the control groups (1 and 2) by ANOVA. No statistically significant differences were observed among the irrigation treatment groups with regard to any of the clinical or bacterial parameters studied. Therefore, the 4 treatment groups were combined into a single group whereby the rate of bacterial repopulation following extensive scaling and root planing could be ascertained. The infection incidence of sites at baseline (of total sites), 1 week and 12 months (of sites originally infected at baseline) was 14/41, 3/14, and 7/14 for Aa; 33/41, 6/33, and 12/33 for Pg; and 37/41, 3/37, and 12/37 for Pi, respectively. Thus, half or fewer of the originally infected sites became reinfected at 12 months despite lack of maintenance therapy. The results suggest that 1) a single episode of pocket irrigation with antimicrobial agents following thorough scaling and root planing did not affect the rate of repopulation of periodontal pockets by the tested pathogens; 2) thorough scaling and root planing has a lasting suppressive effect on selected periodontal pathogens for the majority of sites in patients with adult periodontitis; 3) pre-operative probing depth, the amount of gingival fluid flow and the composition of the subgingival microflora may serve as predictors for reinfection in the absence of maintenance care; and 4) reinfection of the treated sites by Aa, Pg, and/or Pi may constitute a risk factor that diminishes the effect of therapy in the absence of supportive maintenance care.     

Full- versus partial-mouth disinfection in the treatment of periodontal infections. A pilot study: long-term microbiological observations

A standard periodontal treatment consists of 4 to 6 scalings and rootplanings at a 1- to 2-week interval, which allows reinfection of a previously disinfected area before completion of the treatment. The present pilot study aims to examine the microbiological long-term effects of a full-mouth disinfection. 10 patients with advanced chronic periodontitis were randomly allocated to a test and control group. The patients from the control group received scaling and rootplaning and oral hygiene instructions at a 2-week interval. The full-mouth disinfection (test group) consisted of a full-mouth scaling and rootplaning in 2 visits within 24 h in combination with: tongue brushing with 1% chlorhexidine gel for 1 min, mouth rinsing with 0.2% chlorhexidine solution for 2 min and subgingival irrigation of all pockets (3x in 10 min) with 1% chlorhexidine gel. The patients of the test group were instructed to rinse 2x daily with 0.2% chlorhexidine. Plaque samples were taken at baseline and after 1, 2, 4 and 8 months. Differential phase-contrast microscopy showed a significantly larger reduction of spirochetes and motile organisms in the test group up to month 2 for the single-rooted and up to month 8 for the multi-rooted teeth. Furthermore, the culture data supported the effectiveness of the new treatment strategy. In both groups, the number of anaerobic CFU decreased 1 log around single- and 0.5 log around multi-rooted teeth. The number of anaerobic CFU remained low in the test group, in contrast to the control group. At 1 month, the test group harboured a significantly (p<0.01) lower proportion of pathogenic organisms, but this difference disappeared with time. Moreover, the test sites showed a significantly higher (p<0.02) increase in the proportion of beneficial micro-organisms up to 4 months. These findings suggest that a full-mouth disinfection leads to a significant microbiological improvement up to 2 months, which could be consolidated, although not significant, for the next 6 months.     

Studies on the rod-coccus life cycle of Rhodococcus equi

In the present study all 19 Rhodococcus equi cultures isolated from horses and 19 of 22 R. equi cultures isolated from human patients displayed a rod-coccus life cycle after cultivation under defined growth conditions. A bacillary growth could be observed after cultivation of the bacteria in fluid media for 4 h at 37 degrees C, a coccoid morphology after cultivation of the bacteria for 24 h either on sheep blood agar plates or in fluid media. The different morphological features did not significantly influence the typability of the bacteria or the expression of surface proteins including 15-17 kDa virulence proteins. Studies on further surface characteristics revealed a relation between haemagglutinating properties, the surface hydrophobicity and adherence properties of the bacteria to HeLa cells. These properties seemed to be influenced by the cultivation conditions but not by the different morphological forms of the bacteria. A haemagglutination reaction, a hydrophobic surface and an enhanced adherence to HeLa cells could be observed with coccoid bacteria after cultivation in fluid media for 24 h at 37 degrees C but not with coccoid bacteria harvested from sheep blood agar plates or with bacillary bacteria after 4 h growth in fluid media. This difference might possibly be caused by the degree of encapsulation of the bacteria after various cultivation conditions and a subsequent masking effect of the hydrophilic polysaccharide capsule of R. equi.     

Evaluation of BBL CHROMagar orientation medium for detection and presumptive identification of urinary tract pathogens

The microbiological performance of BBL CHROMagar Orientation medium and CPS ID2 agar was compared to that of Columbia agar with 5% sheep blood and MacConkey agar without crystal violet for the enumeration and presumptive identification of bacteria responsible for urinary tract infections. Of a total of 658 clinical urine specimens, 118 specimens yielded no growth, 402 specimens yielded growth with cell counts of > or = 10(5) CFU/ml, and 138 specimens yielded growth with cell counts of < 10(5) CFU/ml. Of the specimens with cell counts of > or = 10(5) CFU/ml, 163 were pure cultures and 239 were mixed cultures. A total of 266 Escherichia coli organisms were isolated on both chromogenic media, 260 were isolated on blood agar, and 248 were isolated on MacConkey agar. One strain (0.4%) failed to develop the expected pink color on CHROMagar Orientation medium, and 23 strains (8.7%) failed to develop the expected pink color on CPS ID2 agar. Enterococci (CHROMagar Orientation medium, n = 266; CPS ID2 agar, n = 265) produced small blue-green colonies on both chromogenic media. Fifty of the mixed cultures contained enterococci that were detected only on the chromogenic media. The Klebsiella-Enterobacter-Serratia (KES) and the Proteus-Morganella-Providencia (PMP) groups could be identified on both chromogenic media. Of 66 isolates of the KES group, 63 grew with the expected color on CHROMagar Orientation medium and 58 of 64 isolates grew with the expected color on CPS ID2 agar. Other microorganisms required further identification. The use of chromogenic medium formulations offers a time-saving method for the reliable detection, enumeration, and presumptive identification of urinary tract pathogens. One of the greatest advantages of these media is the easy recognition of mixed cultures.     

Attachment loss and serum antibody levels against autologous and reference strains of Actinobacillus actinomycetemcomitans in untreated localized juvenile periodontitis patients

Immunological data have been suggested to be a potential tool in the diagnosis, classification and monitoring of periodontal diseases. However, the role of circulating antibodies in periodontal patients is poorly understood. Patients suffering from localized juvenile periodontitis (LJP) are often reported to show high titers of serum IgG antibodies against Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans), but several affected patients do not. Most studies use well-known reference strains of the bacterium for testing against the patients' sera. The aim of the present investigation was to study the relationship between serum IgG antibody levels to autologous A. actinomycetemcomitans strains and clinical attachment loss (CAL). In addition, we wanted to assess the patients' serum titers against 4 well-known reference strains of the bacterium as well as their general potential immunoglobulin response. Intravenous blood samples were taken from 23 LJP patients and 10 healthy individuals, and autologous A. actinomycetemcomitans strains were cultured from 18 of the LJP patients. CAL was measured at 4 different sites around all present teeth and assessed as a % of teeth with at least 1 site moderately > or = 2 < 5 mm) or severely (> or = 5 mm) involved. An enzyme-linked immunosorbent assay (ELISA) was performed to evaluate the serum titers of IgG antibodies to A. actinomycetemcomitans antigens. No significant correlation was found between serum IgG antibody titers to autologous strains and CAL. However, there was a trend that low responders had more moderately affected teeth than had high responders and patients with undetectable A. actinomycetemcomitans levels, which is in agreement with a hypothetically protective role of the antibodies. The total counts of immunoglobulin assessed in all participants showed that the predominant class was IgG and the reference group displayed significantly less (p < 0.05) IgG and IgG1 counts than the LJP patients. Both the reaction pattern against reference and autologous strains varied widely. We conclude that the specific antibody response against A. actinomycetemcomitans shows a weak correlation to clinical attachment levels in LJP patients.     

Oxygen requirements of Aspergillus species

The growth of 24 Aspergillus isolates at low oxygen tensions was assessed. Isolates selected included A. fumigatus (10), A. terreus (6), A. niger (6), A. nidulans (1) and A. flavus (1). Three different agar media were used--potato dextrose agar (PDA), pH 5.6; brain heart infusion (BHI), pH 7.4; and a specially developed medium (Hall's) containing resazurin--with oxygen concentrations of 0, 0.025, 0.1, 0.5 and 2.5%. The CO2 concentration was 5%. Agar plates were inoculated with 2 x 10(7) conidia/ml, loaded into jars and flushed with a special gas mixture at 37 degrees C. The plates were inspected at intervals of 3, 5 and 10 days. On Hall's medium, none of the isolates grew at oxygen concentrations of 0 or 0.025%, but 21 (88%) of 24 grew at 0.1%. On PDA and BH1, all 14 isolates tested grew at oxygen concentrations of 0.5 and 2.5%. Three of these 14 conidiated on PDA at oxygen 0.5% and 12 of 14 conidiated on PDA at oxygen 2.5%. None grew without oxygen on these media. Thus, pathogenic Aspergillus spp. are capable of growth at low oxygen tensions, and this may have implications for pathogenicity and antifungal activity.     

The effects of periodontal therapy on serum antibody levels to Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis (part II)

Levels of IgG and IgM antibodies were estimated against Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were determined by enzyme linked immunosorbent assay (ELISA) in 17 patients with juvenile periodontitis, 15 with adult periodontitis and 24 healthy controls at the beginning of treatment and 3 to 8 months after periodontal therapy. After treatment, antibodies to A. actinomycetemcomitans and P.gingivalis had decreased in patients, but the levels were still significantly higher than in healthy controls. Whether or not an of antibody level against a specific bacteria changes after periodontal treatment is however, still debatable.