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Biomedical subjects

R W Rowland

Publications and source records attributed to R W Rowland.

8 recordsLinked to original sources
PubMed1999

Necrotizing ulcerative gingivitis.

Necrotizing periodontal diseases are unique in their clinical presentation and course. Data suggest that the etiology and pathogenesis of necrotizing periodontal diseases may also be distinctive from other periodontal diseases. Necrotizing ulcerative gingivitis (NUG) is a type of necrotizing periodontal disease in which the necrosis is limited to the gingival tissues. Three specific clinical characteristics must be present to diagnose NUG, pain (usually of rapid onset) interdental necrosis, and bleeding. Epidemiological and prospective clinical studies have found an altered ability to cope with psychological stress, immunosuppression, and tobacco use to be strongly associated with the onset of NUG.

Gingivitis, Necrotizing Ulcerative↗
PubMed1993

Painful gingivitis may be an early sign of infection with the human immunodeficiency virus.

Anecdotal reports have suggested that painful gingivitis may be associated with infection due to the human immunodeficiency virus (HIV). Twenty patients who presented to the emergency department with a chief complaint of gum pain were evaluated for HIV infection, CD4/CD8 T lymphocyte profiles, complete blood cell counts and differentials, and lymphocyte function (response to mitogenic stimulation). Seven of the 20 patients (35%) were seropositive for HIV. Three of the seven HIV-seropositive patients were unaware of their HIV infection until tested in this study (with use of an ELISA and western blotting). The HIV-seropositive patients were significantly older than the HIV-seronegative patients (31.4 +/- 3 years and 24 +/- 1 year, respectively). Two of the seven HIV-seropositive patients presented with severe CD4 lymphocyte depletion. The other five HIV-seropositive patients presented with CD4 lymphocyte counts of 473 +/- 155 (mean +/- SE). Regardless of HIV serological status, all patients demonstrated a severely depressed mitogenic response when compared with control subjects. There were no remarkable differences in complete blood cell counts and differentials within each serological group. Significant differences, however, were noted when CD4/CD8 lymphocyte counts and ratios were measured. Identification of clinical presentations, such as painful gingivitis, that reflect an early stage of HIV infection could aid in the timing of therapy and prevention of the spread of HIV infection.

Adult↗
PubMed1993

Serum IgG and IgM levels to bacterial antigens in necrotizing ulcerative gingivitis.

Previous studies of the systemic antibody response in necrotizing ulcerative gingivitis (NUG) have elicited varying results. The purpose of this study was to determine the humoral response to site-specific isolates of microbiota associated with NUG. Sera from 21 active NUG subjects and 21 age-sex-race matched controls were assessed for IgG and IgM antibodies to 4 clinical isolates of Prevotella intermedia and 3 clinical isolates of Treponema species. P. intermedia and Treponema strains were isolated from active and inactive sites of NUG patients and gingivitis sites of controls. P. intermedia was also isolated from noninflamed sites of the controls. IgG and IgM serum levels to these 7 bacteria were measured by ELISA. Compared to control subjects, the NUG sera exhibited significantly lower IgG and IgM levels to all 4 isolates of P. intermedia (P < or = 0.001). It was also noted that sera from NUG subjects had elevated IgM levels to all 3 spirochete isolates but significantly higher only to the spirochete isolated from a gingivitis site of a control subject (P < or = 0.005). The data suggest that failure to mount a substantial antibody response to P. intermedia may be associated with onset of disease activity in NUG. However, the assumed lack of "biological significance" between differences in antibody responses measured indicates the relationship is weak or nonexistent. It also appears that antibody response to spirochetes is not associated with onset of NUG.

Adolescent↗
PubMed1993

The use of sterile versus nonsterile gloves during out-patient exodontia.

One hundred twenty-four patients who showed no clinical evidence of acute infection, were not taking antibiotics, and were to undergo routine removal of erupted teeth were studied. Patients were alternately assigned to surgeons who were wearing sterile or nonsterile, but clean, gloves. Surgery was performed in the usual manner and no postoperative antibiotics were prescribed. None of the patients was found to be infected postoperatively. Results of this prospective study suggest that routine exodontia can be safely performed by a surgeon wearing nonsterile, but surgically clean, gloves without increasing the risk of postoperative infection.

Ambulatory Surgical Procedures↗
PubMed1986

Interactions of Bacteroides gingivalis with fibrinogen.

Results of previous studies from our laboratory have shown that a strain of Bacteroides intermedius isolated originally from a patient with acute necrotizing ulcerative gingivitis binds and degrades human fibrinogen (M.S. Lantz, L.M. Switalski, K.S. Kornman, and M. Hook, J. Bacteriol. 163:623-628, 1985). We report that strains of Bacteroides gingivalis, an organism implicated in the etiology of several forms of periodontitis, also bind and degrade fibrinogen. The binding is rapid, reversible, saturable, and specific. The number of fibrinogen-binding sites per cell varies from 500 to 1,500 in different batches of bacteria, and the dissociation constant for the complex is on the order of 10(-8) M. B. gingivalis possesses cell-associated fibrinogenolytic activity that is activated by dithiothreitol and blocked by thiol protease inhibitors. Interaction with fibrinogen may mediate colonization and establishment of these organisms in the periodontal microbiota.

Bacteroides↗
PubMed1981

Laboratory evaluation of the AutoMicrobic system for identification of Enterobacteriaceae.

The Enterobacteriaceae Biochemical Card used with the AutoMicrobic system (Vitek Systems, Inc., Hazelwood, Mo.) was compared with the API 20E system (Analytab Products, Plainview, N.Y.) for identifying members of the family Enterobacteriaceae. A total of 1,401 clinical isolates representing 18 species were identified by the AutoMicrobic and API 20E systems over a 5-month period. Discrepancies between these systems were resolved by conventional methods. Overall, 98.3% of the isolates were identified correctly by the AutoMicrobic system in 8 h, with 94.2% having an AutoMicrobic system confidence level greater than or equal to 90%; 92.9% of the isolates were identified correctly by the 20E system after 24 h of incubation. Discrepancies between the two systems occurred in 3.1% of the isolates. Of these, 40.9 and 59.1% proved to be correct by the AutoMicrobic and API 20E systems, respectively.

Bacteriological Techniques↗