A TEM/SEM study of the microbial plaque overlying the necrotic gingival papillae of HIV-seropositive,necrotizing ulcerative periodontitis

The purpose of this study was to examine by transmission (TEM) and scanning electron microscopy (SEM) the supragingival microbial plaque overlying the ulcerated gingival papillae of necrotizing ulcerative periodontitis (NUP) lesions in HIV-seropositive patients. The microbiota of NUP and HIV-seropositive patients with periodontitis has been reported to be similar to that of conventional periodontitis in non-infected subjects, although several investigators have also reported high recovery rates of microbes not generally associated with the indigenous oral microbial flora. Light and electron microscopic observations and microbial culture studies indicate a similar high prevalence of spirochetes in both necrotizing ulcerative gingivitis (NUG) and NUP. In addition, several studies have reported more frequent isolation of Candida albicans from diseased periodontal sites in HIV-seropositive patients than from non-diseased sites. Ten male and six female patients, each HIV-seropositive and exhibiting NUP, constituted the study population. Two biopsies of involved gingival papillae from between posterior teeth were obtained from each patient and processed for examination by both TEM and SEM. Microscopic examination revealed a surface biofilm comprised of a mixed microbial flora of various morphotypes in 81.3% of biopsy specimens. The subsurface flora featured dense aggregations of spirochetes in 87.5% of specimens. Zones of aggregated polymorphonuclear leukocytes and necrotic cells were also noted. Yeasts were observed in 65.6% of specimens and herpes-like viruses in 56.5% of the specimens. Collectively, except for the presence of yeast and viruses, the results suggest that the microbial flora and possibly the soft tissue lesions of NUP and necrotizing ulcerative gingivitis are very similar.     

The Tuskegee Legacy Project: history,preliminary scientific findings,and unanticipated societal benefits

This article is intended to provide a relatively complete picture of how a pilot study--conceived and initiated within an NIDCR-funded RRCMOH--matured into a solid line of investigation within that center and "with legs" into a fully funded study within the next generation of NIDCR centers on this topic of health disparities, the Centers for Research to Reduce Oral Health Disparities. It highlights the natural opportunity that these centers provide for multicenter. cross-disciplinary research and for research career pipelining for college and dental school students; with a focus, in this case, on minority students. Futhermore, this series of events demonstrates the rich potential that these types of research centers have to contribute in ways that far exceed the scientific outcomes that form their core. In this instance, the NMOHRC played a central--and critical, if unanticipated--role in contributing to two events of national significance, namely the presidential apology to the African American community for the research abuses of the USPHS--Tuskegee syphilis study and the establishment of the National Center for Bioethics in Research and Health Care at Tuskegee University. Research Centers supported by the NIH are fully intended to create a vortex of scientific activity that goes well beyond the direct scientific aims of the studies initially funded within those centers. The maxim is that the whole should be greater than the sum of its initial constituent studies or parts. We believe that NMOHRC did indeed achieve that maxim--even extending "the whole" to include broad societal impact. well beyond the scope of important, but mere, scientific outcomes--all within the concept and appropriate functions of a scientific NIH-funded research center.     

Changes in postural stability in women aged 20 to 80 years

BACKGROUND: A study of postural stability was undertaken to identify the relationship between vision and support surface across age decades. Understanding when reliance on vision for postural stability emerges and the support conditions contributing to this instability may provide the evidence required to introduce falls-prevention strategies in younger age decades. METHODS: We measured postural stability in 453 women aged 20 to 80 years using the Balance Master force-plate system while the women performed the modified Clinical Test for the Sensory Interaction and Balance (firm and foam surfaces, eyes open and closed) and the Single-Limb Stance Test (eyes open and closed). RESULTS: Women in their 60s and 70s were more unstable than younger women in bilateral stance on a firm surface with the eyes closed. This instability was evident from the 50s when a foam surface was introduced and from the 40s when single-limb stance was tested with eyes closed. A further decline in stability was demonstrated for each subsequent decade when the eyes were closed in single-limb stance. CONCLUSIONS: Age, visual condition, and support surface were significant variables influencing postural stability in women. Reliance on vision for postural stability was evident for women from the 40s when single-limb stance was tested, from the 50s when bilateral stance on foam was tested, and from the 60s when a firm surface was used. The cause(s) of this decline in stability requires further investigation, and screening for postural instability between the ages of 40 and 60 is advocated.     

Concurrent validity and classification accuracy of the Leiter and Leiter-R in low-functioning children with autism

The concurrent validity of the Leiter International Performance Scale (Leiter) and Leiter International Performance Scale–Revised (Leiter-R) was examined in a sample of children with autism who could not be assessed with more traditional measures of intelligence (e.g., the Wechsler scales). The sample consisted of 26 children ranging in age from 4 to 16 years. The correlation between the Leiter scales was high (r = .87), and there was a difference of 3.7 points between the two mean scores, nonsignificant at both statistical and clinical levels. However, significant intraindividual discrepancies were present in 10 cases, 2 of which were both large (24 and 36 points) and clinically meaningful. The mean profile of performance on Leiter-R subtests is also presented for this sample of children with autism, to allow for comparison with other groups. Based on the results of this initial evaluation, together with the current normative data, good psychometric properties, and availability of global and subtest scores with the Leiter-R, the instrument is generally recommended for use with children with autism. However, because of changes in the design of the Leiter-R, there may be greater clinical success with the original Leiter for those children who are very low functioning and severely affected, particularly younger children.     

Magnetic cell sorting for enriching Schwann cells from adult mouse peripheral nerves

We have devised a simple method to purify mitotically active Schwann cells (SC) from peripheral nerves of adult mice. Nerves were predegenerated in vitro for 7 days and after dissociation cells were plated on poly-L-lysine/laminin coated dishes in N2 serum-free culture medium supplemented with forskolin and heregulin-beta1. Primary cultures were purified from contaminating fibroblasts by magnetic cell sorting (MACS) based on SC membrane specific expression of p75(NGFR) and enriched to about 99% of SC after MACS from 34 to 91% before sorting. After sorting, purified adult mouse SC were propagated for three passages until confluent to a total surface of 160 cm(2) per mouse (two sciatic and two trigeminal nerves). In addition, we show that this method can be used to purify tumoral SC from mouse NF2-related schwannomas.     

Measuring adherence to depression treatment guidelines in a VA primary care clinic

The primary objectives of this pilot study were to develop a measure of adherence for depression practice guidelines and to assess the degree to which providers and patients adhere to guidelines in a VA primary care setting. The Depression Guideline Measure (DGM) is based on three national guidelines. The DGM was used to review medical records of 111 patients with Patient Health Questionnaire (PHQ) scores >or=10. Interrater reliability for 15 of 19 DGM checklist items was excellent (kappa > 0.75). There was a broad range of adherence to guideline criteria: only 13.5% of patients were contacted for follow-up within 2 weeks, while 100% of providers documented follow-up plans. Forty percent of patients saw mental health providers, and 63% were prescribed antidepressants. A secondary objective of the study was to explore the relationship between guideline adherence and changes in PHQ scores. Among 51 patients who completed follow-up PHQs, no associations were detected. The results suggest that the DGM shows promise as a reliable measure of guideline adherence and that guideline criteria are frequently not met in busy primary care clinics. More research is needed to determine the validity of the DGM and the impact of guideline adherence on depression outcomes.