Automated image registration of cerebral digital subtraction angiography.

PURPOSE: Our aim is to automatically align digital subtraction angiography (DSA) series, recorded before and after endovascular thrombectomy. Such alignment may enable quantification of procedural success. METHODS: Firstly, we examine the inherent limitations for image registration, caused by the projective characteristics of DSA imaging, in a representative set of image pairs from thrombectomy procedures. Secondly, we develop and assess various image registration methods (SIFT, ORB). We assess these methods using manually annotated point correspondences for thrombectomy image pairs. RESULTS: Linear transformations that account for scale differences are effective in aligning DSA sequences. Two anatomical landmarks can be reliably identified for registration using a U-net. Point-based registration using SIFT and ORB proves to be most effective for DSA registration and are applicable to recordings for all patient sub-types. Image-based techniques are less effective and did not refine the results of the best point-based registration method. CONCLUSION: We developed and assessed an automated image registration approach for cerebral DSA sequences, recorded before and after endovascular thrombectomy. Accurate results were obtained for approximately 85% of our image pairs.

Specificity of monoclonal antibodies reactive with Fusobacterium nucleatum: effect of formalin fixation.

Monoclonal antibody specific for Fusobacterium nucleatum was reacted with untreated and formalin fixed F. nucleatum cells by an enzyme-linked immunosorbent assay (ELISA) and by indirect immunofluorescence. Treatment of bacterial cells with formalin destroyed the antigenic determinant responsible for reactivity with this monoclonal antibody in both assays. Formalin fixation had no effect on hemagglutination activity (HA) of F. nucleatum cells or reactivity with polyvalent rabbit antiserum in double diffusion in agar. Scanning electron microscopy demonstrated that formalin fixation did not affect binding of F. nucleatum cells to microtiter plates. When developing monoclonal antibodies to be used as diagnostic reagents, the antigenic form utilized for immunization should be identical to the antigenic form which will eventually be used in the diagnostic assay.

Accelerated healing of carbon dioxide laser burns in rats treated with composite polyurethane dressings.

Healing time, infection rate, and residual scar formation were compared in carbon dioxide laser burns in rats treated in four ways: Spandra composite dressing, OpSite composite dressing, Petrolatum Gauze (USP), and no treatment. There were no infections and no differences in scar formation among the treatment groups. The mean healing times were ten days for the polyurethane dressings (Spandra and OpSite), 13 days for Petrolatum Gauze, and 16 days for the untreated group. Spandra was easier to apply and handle than OpSite. These findings suggest that synthetic gas-permeable dressings promote healing after cutaneous carbon dioxide laser surgery more effectively than conventional treatments of ointment-impregnated gauze or leaving the wound exposed to the air.

Systemic antibody response of clinically characterized patients with antigens of Eubacterium brachy initially and following periodontal therapy.

Eubacterium brachy, a gram-positive anaerobic rod, has been implicated by cultural studies to be associated with the microflora of periodontal diseases. Serum samples from 184 clinically characterized patients were evaluated in a standardized enzyme-linked immunosorbent assay (ELISA) for reactivity to E. brachy antigens. Sera from clinically healthy subjects (HS) served as controls. Sera from rapidly progressive periodontitis (RP) patients demonstrated significantly greater reactivity by ELISA than did HS when reactivity with E. brachy antigens was determined (P less than 0.05). Juvenile periodontitis (JP) and adult periodontitis (AP) patients did not differ in reactivity by ELISA from HS (P greater than 0.05). Three to 4 years following successful periodontal therapy, reactivity was not significantly altered in any patient group (P greater than 0.05). The possible significance of these findings and the importance of an extracellular antigen of E. brachy in the immunopathology of periodontal diseases are discussed.

Assessment of attached gingiva using the tension test and clinical measurements.

The attached gingiva on the facial surface of the mandibular central incisors was evaluated by measurements and the "tension test" on 226 subjects between the ages of 8 and 22 years. Findings of significance were: 1. As age increased a definite increase in width of attached gingiva occurred. 2. There was no increase in the frequency of a positive tension test in older age groups. 3. No relationship was observed when results of the tension test were compared with clinical measurements of attached gingiva.

Eubacterium brachy. Reactivity in in vitro bone resorptive bioassay.

Recent studies have demonstrated an association of Eubacterium sp. with the subgingival microflora of patients with chronic periodontitis. One species, Eubacterium brachy, was evaluated to determine the possible mechanisms by which this microorganism may contribute to this disease. An extracellular antigen was identified in the culture supernatant which reacted with antibodies in human sera. This antigen was isolated by methanol precipitation and purified by gel filtration. The purified extracellular antigen was reacted in vitro with 45CaCl2-labeled fetal rat bone in a bone resorptive bioassay. This antigen was shown to have a molecular weight of 170,000, to share a line of identity with a sonicated preparation of E. brachy whole cells and to result in increased 45CaCl2 release from fetal rat bones when cultures were exposed to the purified extracellular antigen at concentrations of 10 to 53 micrograms/ml.

Endotoxin levels in periodontally healthy and diseased sites: correlation with levels of gram-negative bacteria.

This study investigated the correlation between endotoxin levels and the percentage of Gram-negative bacteria in healthy sites and in periodontitis sites. Twelve healthy adults participated. Each subject provided 3 periodontitis sites with 5 to 8 mm probing depths that bled on gentle probing and 3 healthy sites with sulcus depths of 1 to 3 mm that did not bleed. Clinical examinations and sterile paper point sampling of all study sites were conducted on days 0, 7, and 14, and site-specific endotoxin levels and percentage of Gram-negative bacteria were determined. There were significant differences in both endotoxin levels and percentage Gram-negative bacteria between healthy and periodontitis sites across all 3 sampling periods, but no difference across sampling periods in the healthy sites and the periodontitis sites, respectively. Correlation coefficients revealed a high degree of correlation between site-specific endotoxin levels and percentage of Gram-negative organisms. Using a sample dilution of 1 x 10(4), endotoxin levels differentiated healthy from periodontitis sites with a specificity of approximately 91% and a sensitivity of approximately 90%.

Biologic activity of type I and type II Fusobacterium nucleatum isolates from clinically characterized sites.

Fusobacterium nucleatum is a microorganism commonly cultured from periodontal disease sites. F. nucleatum isolates (120) were obtained from subgingival plaque samples taken from 27 clinically characterized sites using a selective culture medium. All isolates were verified by morphology, Gram-stain reactions, oxygen tolerance and biochemical reactions. A total of eight clinical isolates and two typed strains were used for further evaluation. In this study, there was no relationship found between GI and probing depth or between probing depth and frequency of isolation of Type I or Type II F. nucleatum colonies. There was a significant increase in isolation of Type II colonies with a GI of 2 (P less than 0.0001). All isolates tested shared lines of identity by double diffusion in agar and displayed similar ability to hemagglutinate sheep erythrocytes and a reduction in this hemagglutination activity by previous exposure to 50 mM D-galactose. All isolates tested showed similar protein patterns as determined by polyacrylamide gel electrophoresis. By the methods used, no differences were detected between Type I and Type II F. nucleatum; however, there was a statistically significant increase in Type II isolates with increasing levels of gingivitis.

Reaction of human sera from juvenile periodontitis, rapidly progressive periodontitis, and adult periodontitis patients with selected periodontopathogens.

The levels of serum antibody reactive to selected periodontopathogens were determined in 182 clinically characterized patients: 35 healthy control, 50 juvenile periodontitis, 42 adult periodontitis and 55 rapidly progressive periodontitis. Reactive antibody levels were determined using an enzyme-linked immunosorbent assay with whole cell preparations of Bacteroides gingivalis, Capnocytophaga (Bacteroides) ochraceus, Fusobacterium nucleatum and Actinobacillus actinomycetemcomitans (Y-4) serving as antigens. Increased reactivity to B. gingivalis and F. nucleatum was observed in all three disease groups studied while antibody reactive to A. actinomycetemcomitans was increased in juvenile and rapidly progressive periodontitis. Antibody levels reactive to C. ochraceus in healthy subjects did not differ from those observed in any disease patient groups. Possible implications in the etiology and progression of the diseases coupled with environmental changes which occur in the econiche of the periodontal pocket are described.

The ELISA system for measuring antibody reactive to Fusobacterium nucleatum in the sera of patients with chronic periodontitis.

Humoral IgG, IgA and IgM responses to three typed oral strains of F. nucleatum were examined in patients with chronic periodontitis and in individuals with clinically healthy gingiva. Attempts were made to isolate F. nucleatum from either the pathologic gingival crevices or healthy sulci in this study. Higher levels of IgG and IgA reactive to all three strains were observed in the chronic periodontitis patients; however, there were no differences between the IgM levels in the diseased and healthy individuals. Immunodiffusion studies with rabbit antiserum and adsorption studies of the human sera demonstrated a sharing of antigenic determinants by the F. nucleatum strains. F. nucleatum strains were isolated from 14 of the 15 individuals in the study.

A comparison of the reactivity of Eubacterium species with localized and serum immunoglobulins from rapidly progressive and adult periodontitis patients.

Immunoglobulins in sera and in supernatant fluids of explant cultures of diseased gingival tissues from 20 rapidly progressive and 20 adult periodontitis sites were tested by an ELISA assay for reactivity with typed strains of Eubacterium alactolyticum, E. brachy, E. limosum and E. nodatum. Immunoglobulins present in tissue culture fluids from both rapidly progressive and adult periodontitis samples reactive with E. brachy and E. nodatum were significantly greater (P less than 0.05) than those reactive with E. alactolyticum or E. limosum. The titers to E. brachy in tissue culture fluids from adult periodontitis were significantly greater (P less than 0.05) than those from rapidly progressive periodontitis; there was no difference in titers to the other three species. The only significant difference in serum titers was that sera from patients with rapidly progressive periodontitis had significantly greater reactivity to E. alactolyticum than did sera from adult periodontitis patients. These data indicate that immunoglobulins in the sera of rapidly progressive and adult periodontitis patients do not necessarily reflect the reactivity of localized immunoglobulins present in the diseased gingival tissue explant culture fluids from these patients.

Clinical and laboratory characterization of early onset periodontitis.

Clinical and laboratory data were compared in 72 patients with localized periodontitis (LP) and 103 patients with generalized periodontitis (GP). Significantly more LP than GP cases had decreased neutrophil chemotaxis (CTX), and were seropositive for Actinobacillus actinomycetemcomitans (Aa). Significantly, more GP cases were seropositive for Bacteroides gingivalis (Bg). All clinical indices were similar on affected teeth in LP and GP, but the attachment loss was greater on clinically unaffected teeth in GP when compared with LP. LP cases with CTX defects had a significantly lower mean age, were more often seropositive for Aa antibodies, and were more often female than LP patients with normal CTX. Significantly more GP cases with CTX defects were seropositive for Aa antibody. GP patients with normal CTX had a higher plaque index on both affected and unaffected teeth than did GP patients with a CTX defect. Our data suggest that chemotaxis and/or specific bacteria may be contributory, but not always necessary, factors in these disorders. The overlap in clinical and laboratory profiles of LP and GP continues to cloud the distinction of these early onset forms of periodontitis.

Spandra: a sustained release battlefield wound dressing.

In 1981, our laboratories developed a family of elastomers which could be cured by ultraviolet (UV) radiation. Curing by UV radiation was a significant advance in chemistry, since it allowed ultra-fast curing of elastomers in a matter of seconds, as compared to several hours at 110 degrees C for conventional heat curing. We applied for a patent based on this technology, and the patent was allowed in mid-1984 [29]. Based on this technology, Thermedics submitted a proposal to the US Army for the development of a sustained-release battlefield wound dressing containing antibiotics and coagulants. The drugs were evenly distributed in the oligomer matrix, and subsequently cured in seconds under UV illumination, without the use of heat, organic solvents or water. Because delicate drugs are not subjected to heat, organic solvents or water, the pharmacological activity of the drugs is insured. Therefore, theoretically any drug may be incorporated into our dressing. Sustained release dressings were first developed at Thermedics in 1983, spurred by a contract from the US Army Medical Research and Development Command. Under this contract, the Company developed a new type of wound dressing capable of accelerating the healing process, retarding infection, and minimizing pain. Based on our TECOFLEX materials technology, the dressing performs like temporary artificial skin. Its transmission properties for oxygen, carbon dioxide, and water vapor are similar to those of intact skin. Thus, while excluding bacteria from the wound site, the dressing maintains an optimal moist environment for the promotion of rapid healing. The new drawing shown in Figure 10 minimizes pain during healing by preventing dehydration and shrinkage in the wound. Patient comfort is also enhanced by the incorporation of a special fabric which imparts flex properties to the bandage that are almost identical to those of human skin, with greater stretch in one direction than in another. This also facilitates application to complex body contours by only one attendant, an important feature in both hospital and emergency situations. Materials currently in use in hospitals are difficult to handle, requiring two or three nurses to apply large dressings. Thermedics' military wound dressing not only has the significant advantage of ease of application, but this dressing can also be used for delivery of drugs to a specific site.(ABSTRACT TRUNCATED AT 400 WORDS)

Comparative efficacy of an antiseptic mouthrinse and an antiplaque/antigingivitis dentifrice. A six-month clinical trial.

BACKGROUND: The efficacy of an essential oil-containing antiseptic mouthrinse (Listerine Antiseptic, Pfizer) and an antiplaque/antigingivitis dentifrice (Colgate Total, Colgate-Palmolive) has been demonstrated in numerous double-blind clinical studies. This study was conducted to determine their comparative efficacy. METHODS: Three hundred sixteen subjects with mild-to-moderate gingival inflammation and plaque received a dental prophylaxis and began their randomly assigned brushing and rinsing regimen in an unsupervised setting. Subjects brushed for one minute and rinsed with 20 milliliters for 30 seconds twice daily for six months. The three groups were L (control toothpaste/Listerine rinse), T (Colgate Total toothpaste/control rinse) and P (control toothpaste/control rinse). RESULTS: Subjects in the L and T groups demonstrated statistically significantly lower (P < .001) Modified Gingival Index, or MGI; Bleeding Index, or BI; and Plaque Index, or PI, at both three and six months than subjects in the P group. The magnitude of reduction for the L group was 22.9 percent, 70 percent and 56.1 percent, respectively, and for the T group, 20.8 percent, 58 percent and 22.1 percent, respectively. Subjects in the L group were not different from subjects in the T group in regard to visual signs of gingivitis (MGI), but were more effective (P < .001) than subjects in the T group in experiencing reduced BI and PI. No product-related adverse events were reported. CONCLUSION: Although the Listerine Antiseptic and Colgate Total antiplaque/antigingivitis products produced similar, clinically significant reductions in gingivitis (as measured by MGI and BI), Listerine, when used in conjunction with a fluoride dentifrice and usual oral hygiene, provided a greater benefit in reducing plaque. CLINICAL IMPLICATIONS: When considering an antiplaque/antigingivitis product to recommend to patients, clinicians should consider Listerine Antiseptic, in conjunction with usual oral hygiene, if more rigorous plaque control is desired.

Antiseptic mouthrinse-induced microbial cell surface alterations.

This study determined the effect of an essential oil-containing mouthrinse, Listerine Antiseptic, on microbial cell surface morphology using scanning electron microscopy. Twenty-four hour cultures of C. albicans, A. viscosus, S. sanguis, F. nucleatum, and A. actinomycetemcomitans were harvested and washed in buffer. Triplicate samples were overlaid on poly-L-lysine coated coverslips, immersed in either Listerine or buffer for 30 seconds, fixed in glutaraldehyde followed by post-fixing in 1% osmium tetroxide, dehydrated, and embedded in Peldri II. Exposure of the microorganisms to Listerine Antiseptic for 30 seconds resulted in distinct morphological alterations of cell surfaces suggestive of loss of cell surface integrity. The extent of alteration varied among the structurally different species; cell surface roughening was mild in S. sanguis but extensive in the other microorganisms which developed distinct surface blebs and other abnormalities after the 30-second exposure. These results suggest that a brief exposure to Listerine produces significant morphological changes which may be associated with cell death and may help explain the alteration of surface-associated activities demonstrated in previous studies.

Reduction of viable bacteria in dental aerosols by preprocedural rinsing with an antiseptic mouthrinse.

Two double-blind controlled clinical studies were conducted to determine the efficacy of preprocedural rinsing with Cool Mint Listerine Antiseptic mouthrinse on the level of viable bacteria recovered from dental aerosols when generated immediately after and 40 minutes after rinsing. Eighteen healthy subjects participated in each study. In the first study, following a 24-hour no-oral-hygiene period, subjects received a 10-minute ultrasonic scaling of a randomly chosen half mouth, rinsed with either Cool Mint Listerine or a control, and received an ultrasonic scaling of the remaining half mouth. During each scaling period, aerosolized bacteria were collected on a sterile filter using a modified air-sampling device. The filters were overlaid on culture media, incubated aerobically, and colonies were counted. The second study followed the same basic design except that ultrasonic scaling was done for 5 minutes, and the post-rinsing sampling was performed following a 40-minute simulated dental treatment period. Rinsing with Cool Mint Listerine resulted in a 92.1% reduction in viable bacteria in aerosols generated immediately after rinsing and a 91.3% reduction in aerosols generated 40 minutes after rinsing. These reductions were significantly greater than control (P = 0.0001). These studies suggest that preprocedural rinsing with Cool Mint Listerine Antiseptic may potentially reduce the risk of cross contamination in the dental operatory.

Clinical effectiveness of essential oil-containing dentifrices in controlling oral malodor.

PURPOSE: To assess the efficacy of two essential oil-containing dentifrices in the reduction of human intrinsic oral malodor ("morning bad breath"). MATERIALS AND METHODS: Two clinical trials were conducted which used observer-blind, negative control, parallel designs. To insure a homogeneous test population with similar oral odor characteristics, subjects followed instructions that included toothbrushing with a standard ADA-accepted fluoride dentifrice the night before. On odor evaluation days, subjects refrained from all oral hygiene procedures and from eating or drinking any food or beverage or smoking prior to and during the odor evaluations. Eighty healthy adult subjects in the first trial and 90 in the second trial with qualifying baseline levels of oral malodor participated. Odor ratings of each subject's breath were made by 4-5 trained judges using a nine point hedonic scale, i.e., 1 = most pleasant, 5 = neutral, 9 = most unpleasant. Qualifying subjects were randomly assigned one of two essential oil dentifrices or a negative control dentifrice. Subjects brushed with their assigned dentifrice for 60 s, rinsed with 20 ml of water for 10 s, and received post-treatment hedonic odor ratings at 30, 60, 90, 120, 180, and 240 min. Data were analyzed using an ANCOVA to adjust for baseline scores. RESULTS: The essential oil dentifrices were significantly more effective (P < or = 0.033) than the control in reducing intrinsic oral malodor from 90 to 120 min.

Effect of an essential oil-containing dentifrice on dental plaque microbial composition.

PURPOSE: To determine the effect of 6 months use of an essential oil-containing (EO) antiplaque/antigingivitis fluoride dentifrice on the balance of the oral microbial flora and on the emergence of resistant microbial forms by analysis of dental plaque and saliva. MATERIALS AND METHODS: The dentifrice essential oils consisted of a fixed combination of thymol, menthol, methyl salicylate, and eucalyptol. An identical fluoride-containing dentifrice without the essential oils served as the control. A subgroup of 66 subjects from a clinical trial population of 321 was randomly selected for characterization of their dental plaque microflora. Saliva was also cultured to monitor for the emergence of opportunistic pathogens. Supragingival plaque and saliva were harvested at baseline, after which subjects received a dental prophylaxis. Subjects were sampled again after 3 and 6 months of product use prior to clinical examination. Plaque was characterized for microbial content by phase contrast microscopy for recognizable cellular morphotypes and by cultivation on nonselective and selective culture media. Determination of the minimum inhibitory concentrations of the test agent against selected Actinomyces and Veillonella isolated bacterial species was conducted at all time points to monitor for the potential development of bacterial resistance. RESULTS: There were no statistically significant differences between the microbial flora obtained from subjects using the essential oil-containing dentifrice and the vehicle control for all parameters and time periods except for the percentage of spirochetes at 6 months and for percentage of "other" microorganisms at 3 months. The EO group exhibited a lower adjusted mean for both parameters. Additionally, there was no evidence of the development of bacterial resistance to the antimicrobial activity of the essential oils or the emergence of opportunistic pathogens.

In vivo antimicrobial activity of an essential oil-containing mouthrinse on interproximal plaque bacteria.

This study determined the in vivo interproximal bactericidal efficacy of an essential oil-containing antiseptic mouthrinse (Listerine Antiseptic) following toothbrushing. Thirty-four generally healthy adults, aged 23-64 years, completed this evaluator-blind, randomized, controlled, crossover designed study. Subjects rinsed for 30 seconds with 20 ml of either the essential oil rinse or a negative control rinse. Five minutes later, interproximal plaque was collected using paper points, and recoverable bacterial counts were quantified using both end point dilution and spectrophotometric methods. The results from the end point dilution demonstrated a statistically significant (p < 0.001) 43.8% reduction in recoverable plaque bacteria from interproximal spaces following rinsing with the essential oil mouthrinse. This study suggests that the clinical effectiveness of the essential oil mouthrinse against plaque and gingivitis may be attributable to the rapid kill and plaque permeabilizing properties of the formulation.