PubMed Health⌕ Search

Biomedical subjects

M E Alves

Publications and source records attributed to M E Alves.

17 recordsLinked to original sources
PubMed2000

Oral mucosal lesions and HIV viral load in the Women's Interagency HIV Study (WIHS).

The prevalence of oral lesions was assessed in a five-center subset of the Women's Interagency HIV Study (WIHS) and correlated with other features of HIV disease. Oral examinations were performed by dental examiners on 729 women (577 HIV-positive and 152 HIV-negative) during baseline examination. Significant differences between the groups were found for the following oral lesions: pseudomembranous candidiasis, 6.1% and 2.0%, respectively; erythematous candidiasis, 6.41% and 0.7%, respectively; all oral candidiasis, pseudomembranous and/or erythematous, 13.7% and 3.3%, respectively. Hairy leukoplakia was observed in 6.1% of HIV-positive women. No significant differences were found for recurrent aphthous ulcers, herpes simplex lesions, or papillomas. Kaposi's sarcoma was seen in 0.5% of HIV-positive and 0% of HIV-negative women. Using multiple logistic regression models controlling for use of antiretrovirals and antifungals, in HIV-positive women the presence of oral candidiasis was associated with a CD4 count <200 cells/microl, cigarette smoking, and heroin/methadone use; the presence of hairy leukoplakia was not related to CD4 count but was associated with high viral load. Oral candidiasis and hairy leukoplakia are confirmed as being common features of HIV infection in women and appear to be associated with HIV viral load, immunosuppression, and various other behaviorally determined variables.

AIDS-Related Opportunistic Infections↗
PubMed2000

The use of demineralized freeze-dried bone-glycoprotein matrix grafts in treating baboon periodontal infrabony defects.

In an effort to improve regenerative capacity and establish higher levels of predictability, the use of a new graft material was investigated in baboon infrabony periodontal defects. A graft matrix composed of human demineralized freeze-dried bone combined with human connective tissue glycoprotein was implanted in 20 defects in 9 baboons. Control, debrided-only sites in the same animal served as a comparison. Grafted sites achieved a 1.8-mm greater reduction in probing depth and attachment gain compared to controls. In addition, 25.3% greater defect fill was found in grafted sites. Histologic analyses provided evidence of bone induction by the graft matrix and regeneration of new cementum, periodontal ligament, and bone in the grafted sites.

Alveolar Bone Loss↗
PubMed1996

A multi-center clinical trial of a new chairside test in distinguishing between diseased and healthy periodontal sites. II. Association between site type and test outcome before and after therapy.

The aim of the present study was to evaluate the association between the outcome of a chairside test measuring gingival crevicular fluid (GCF) levels of the enzyme aspartate aminotransferase (AST) and other clinical measures of disease including probing depth, severity of inflammation, and GCF flow before and after therapy. We studied 91 patients with moderate to severe periodontitis. Eight sites with probing depths between 5 mm and 8 mm and obvious signs of inflammation were selected and designated diseased sites. Four sites with probing depth < or = 3 mm with no or minimal signs of inflammation were selected and designated non-diseased sites in patients. Thirty healthy individuals were enrolled and four sites in each were selected and designated healthy controls. Patients were treated with scaling and root planing and control subjects with supragingival prophylaxis. Measurements including GCF volume, gingival inflammation, and probing depth were performed at screening baseline, 1 week later at pretreatment baseline, and at weeks 2 and 4 after treatment. AST content of GCF was measured using a chairside colorometric test. It was concluded that the outcome of the test is an effective objective measure distinguishing between diseased sites and non-diseased sites in patients and control subjects when evaluated both prior to and following application of therapy. Use of this simple chairside test, when combined with other standard diagnostic procedures, provides an objective measurement permitting improved capacity to distinguish between diseased and non-diseased periodontal sites, and to better assess and monitor the outcome of therapy.

Adult↗
PubMed1995

A multicenter clinical trial of PerioGard in distinguishing between diseased and healthy periodontal sites. (I). Study design, methodology and therapeutic outcome.

We designed and performed a multicenter clinical trial to determine the relationship between measurements of the level of the enzyme aspartate aminotransferase (AST) in gingival crevicular fluid (GCF) to other measures used to detect periodontal disease and monitor outcome of treatment, including pocket depth and gingival inflammation. 32 periodontitis patients were enrolled at the University of Washington, Seattle, 30 at the University of Florida, Gainesville, and 34 at the University of Illinois, Chicago. 10 periodontally normal control subjects were enrolled at each location. 8 diseased and 4 healthy sites were designated for study in each patient and 8 healthy sites designated in each control subject. Measures of disease included pocket depth, severity of gingival inflammation, and GCF volume. AST levels were measured using the PerioGard test kit. Clinical measurements were made and GCF samples harvested and tested 2x before and 2x after therapy consisting of scaling and root planing under local anesthetic. Specific design and other issues are discussed, including selection of patients and control subjects, sample size, selection of experimental test sites, methods for assessment of diseased and therapeutic improvement, harvesting of GCF and selection of appropriate biostatistical methods for data analysis. Demographics of the patient populations at the 3 locations are reported. As expected, therapy induced only negligible changes in the measures of disease at healthy sites in control subjects, and relatively minor improvement in healthy sites in patients. In contrast, statistically significant improvement relative to pretreatment baseline status in all 3 measures of disease was observed for diseased sites at all 3 study locations with all p-values less than 0.0002. The magnitude of improvement was comparable to that reported previously by others. The % of PerioGard-positive sites decreased significantly between the screening baseline and both post-treatment visits for patients at all 3 locations, with p values of 0.0001 to <0.0008.

Adult↗
PubMed1995

Platelet association with gingival tissue inflammation.

Platelets (PL) may be involved in the inflammatory process through the release of a variety of factors which could contribute to gingival tissue injury. Thus, conditions which result in the localized discharge of PL constitutents could lead to amplification of the inflammatory process at these sites. The purpose of this study was to determine if there was evidence of PL activation in gingival crevicular fluid and whether the degree of gingival inflammation, as measured by the gingival index (GI), was associated with the degree of platelet activation. This was monitored by assaying for beta-thromboglobulin (beta-TG), a platelet specific protein released from alpha granules of PL when activated. One uL samples of the fluids were obtained from human subjects from gingival sites with various GI scores. Fluid samples were also obtained at probe-induced bleeding gingival crevicular sites. beta-TG levels in the various fluids obtained from the crevice were determined by radioimmunoassay (RIA). The RIA data indicated that detectable beta-TG levels were observed in all samples, the means ranging from 5.5 ng/ml to 45.2 ng/ml. Additionally, a positive association between the GI scores of 0 and 1 and the beta-TG levels where observed. For GI scores of 2 and above the beta-TG concentrations appeared to approach a maximum value. These findings provide evidence for PL activation and suggest a relationship with gingival inflammation.

Adult↗
PubMed1991

A longitudinal study of aspartate aminotransferase in human gingival crevicular fluid.

Previous studies have shown that aspartate aminotransferase (AST), an established serum marker for cardiac and liver damage in humans, appears in elevated concentrations in samples of gingival crevicular fluid (GCF) from ligated vs. non-ligated teeth in beagle dogs and in elevated quantities in cross-sectional GCF sampling, adjusted for collection time, from human sites with clinical signs of past or present periodontal disease as compared to healthy sites. This paper describes a longitudinal study in which AST was monitored quarterly over a 2-year period at 2 sites/tooth in 31 patients with mild to moderate adult periodontitis. In this study sample, 40 (2.6%) of 1536 sites exhibited confirmed loss of at least 2 mm of attachment during the 2-yr observation period. In comparison with healthy sites within the same patients, AST standardized to a 30-second collection interval (AST30) was elevated at these sites with new confirmed attachment loss, and at sites with past attachment loss or gingivitis in the absence of periodontitis. When both within- and between-patient variation were taken into account, observed odds-ratios associating enzyme with disease were higher for sites with new attachment loss (9-16 depending on test cut-point) than for sites with pre-study attachment loss (3-12), or gingivitis in the absence of periodontitis (5-8). AST in GCF is strongly related to human periodontal disease. The data are consistent with the hypothesis that the relationship is strongest during episodes of cumulative tissue breakdown, but the small numbers of sites with confirmed attachment loss during the study period, or with gingivitis in the absence of periodontitis, means that further clinical studies are necessary to clarify this issue.

Adult↗
PubMed1991

A cross-sectional analysis of aspartate aminotransferase in human gingival crevicular fluid.

Previous investigation has shown that the concentration of aspartate aminotransferase (AST), an established serum marker for cardiac and liver damage in humans, is significantly elevated in samples of gingival crevicular fluid (GCF) from ligated teeth in beagle dogs. This paper reports on a cross-sectional study of the relationships between AST in GCF and clinical indices of human periodontal disease in 60 patients with mild to moderate adult periodontitis. AST standardized to a 30-second collection interval (AST30) showed substantial (multiple regression R2 = 0.61) association with summary indices of patient disease status, modest association (partial R2 = 0.22) with tooth disease status within patient, and weaker (partial R2 = 0.12) but statistically significant association with site-to-site variation in disease at the same tooth. AST concentration showed modest (R2 = 0.30) between-patient relationship with clinical indices, but no clinically significant relationship with these indices between sites within patients, suggesting a rough proportionality between accumulated enzyme and GCF volume at sites with varying stages of disease. The relationship between GCF volume and probing depth also appears central to interpretation of enzyme assays. Clinical measures of past periodontitis and current inflammatory disease are cross-sectionally related to variation in AST30, across patients and sites within the same patient. Considerable residual variation, especially elevated AST30 in the absence of clear signs of disease, may result from varying levels of current disease activity, not reflected in clinical measures.

Adult↗
PubMed1991

Association of gingival crevicular fluid aspartate aminotransferase levels with histopathology during ligature-induced periodontitis in the beagle dog.

Previous investigations have shown a clear association between the presence of the enzyme aspartate aminotransferase (AST) in gingival crevicular fluid (GCF) and clinical evidence of periodontal disease in humans, as well as in the beagle dog model. This paper describes a 26-week study that uses the beagle dog model of ligature-induced periodontitis in which GCF-AST (corrected for collection time) was correlated with microscopic evidence of tissue destruction in the periodontium at the sites of fluid collection. GCF and clinical data were collected at baseline, at optimal gingival health, during gingivitis, and after ligation. A cross-mouth design was implemented so that six premolar teeth in each dog were ligated for periods up to five weeks. Formalin-fixed tissues from the sites of GCF collection were prepared for light microscopy and evaluated for the presence of epithelial ulceration, bone resorption, and inflammatory cell infiltration. The relationship between GCF-AST levels and microscopic findings was analyzed by calculation of sensitivity and specificity and by plots of Receiver Operating Characteristics. These data revealed a correlation between elevated enzyme concentration and microscopic evidence of disease activity. Taken together with human studies, these results provide support for the use of AST as a marker of periodontal disease progression.

Alveolar Bone Loss↗
PubMed1991

Disarming canine teeth of nonhuman primates using the submucosal vital root retention technique.

Removing or reducing the size of canine teeth of baboons and macaques has become an accepted practice to minimize the potential for injury to laboratory animal care personnel. A submucosal vital root retention procedure was adapted from the technique of root banking human teeth. In this technique, the crown of a tooth is amputated below the level of the alveolar bone crest, and the exposed pulp covered by a mucoperiosteal gingival flap. Our aim was to disarm the canine teeth of baboons and macaques with a single surgical procedure that would preserve a vital tooth root buried in alveolar bone under normal mucosa. Our long-term objective was to develop a technique that would not require further clinical management during the life of the animal. This paper presents the surgical techniques used.

Animals↗
PubMed1987

Topographic distribution of Thy-1 positive cells in epithelial tissues of BALB/c mice.

Epithelial sheets prepared from murine oral epithelia (palate, lining mucosa, gingiva) and oesophagus contained dendritic and round Thy-1 positive (+) cells similar to those observed in epidermis by immunofluorescence microscopy. Bladder, intestine and tracheal epithelium did not contain such cells. Thus, cells bearing the cells-surface glycoprotein Thy-1, like Ia-antigen-bearing Langerhans cells, may be restricted to stratified squamous epithelia.

Animals↗
PubMed1984

Direct effects of minoxidil on epidermal cells in culture.

Minoxidil, a potent antihypertensive agent, induces generalized hypertrichosis when administered systemically, or localized hair regrowth when applied topically to sites of severe alopecia areata. The pharmacologic mechanisms by which minoxidil stimulates hair growth are unknown. This study was designed to examine whether minoxidil has direct effects on neonatal murine epidermal cells in culture. In the presence of minoxidil, cultures showed a marked dose-dependent second peak of DNA synthesis 8-10 days after culture initiation. In addition, two morphologically distinct cell types appeared. Indirect immunofluorescence staining with keratin-specific antibody revealed cytoplasmic keratin fibers, suggesting the epidermal origin of these cells. Our experiments demonstrate that minoxidil can affect epidermal cells in culture by altering their growth pattern and phenotypic appearance.

Animals↗
PubMedDate not supplied

Controlled tissue expansion with guided bone regeneration.

Guided tissue regeneration techniques are used to create new bone around implant defects and to augment edentulous ridges prior to implant placement. A new technique, tested successfully in baboons, utilizes soft tissue expanders prior to implant placement and tissue regeneration procedures.

Alveolar Bone Loss↗