Genome-wide association study of periodontal pathogen colonization

Pathological shifts of the human microbiome are characteristic of many diseases, including chronic periodontitis. To date, there is limited evidence on host genetic risk loci associated with periodontal pathogen colonization. We conducted a genome-wide association (GWA) study among 1,020 white participants of the Atherosclerosis Risk in Communities Study, whose periodontal diagnosis ranged from healthy to severe chronic periodontitis, and for whom "checkerboard" DNA-DNA hybridization quantification of 8 periodontal pathogens was performed. We examined 3 traits: "high red" and "high orange" bacterial complexes, and "high" Aggregatibacter actinomycetemcomitans (Aa) colonization. Genotyping was performed on the Affymetrix 6.0 platform. Imputation to 2.5 million markers was based on HapMap II-CEU, and a multiple-test correction was applied (genome-wide threshold of p < 5 × 10(-8)). We detected no genome-wide significant signals. However, 13 loci, including KCNK1, FBXO38, UHRF2, IL33, RUNX2, TRPS1, CAMTA1, and VAMP3, provided suggestive evidence (p < 5 × 10(-6)) of association. All associations reported for "red" and "orange" complex microbiota, but not for Aa, had the same effect direction in a second sample of 123 African-American participants. None of these polymorphisms was associated with periodontitis diagnosis. Investigations replicating these findings may lead to an improved understanding of the complex nature of host-microbiome interactions that characterizes states of health and disease.

Changes in gingival crevicular fluid inflammatory mediator levels during the induction and resolution of experimental gingivitis in humans

AIM

The goal of this study is to characterize the changes in 33 biomarkers within the gingival crevicular fluid during the 3-week induction and 4-week resolution of stent-induced, biofilm overgrowth mediated, experimental gingivitis in humans.

METHODS

Experimental gingivitis was induced in 25 subjects for 21 days followed by treatment with a sonic powered toothbrush for 28 days. Clinical indices and gingival crevicular fluids were collected weekly during induction and biweekly during resolution. Samples were analysed using a bead-based multiplexing analysis for the simultaneous measurements of 33 biomarkers within each sample including cytokines, matrix-metalloproteinases (MMPs) and adipokines. Prostaglandin-E(2) was measured by enzyme-linked immunoadsorbant assay. Statistical testing using general linear models with structured covariance matrices were performed to compare stent to contralateral (non-stent) changes in clinical signs and in biomarker levels over time.

RESULTS

Gingivitis induction was associated with a significant 2.6-fold increase in interleukin 1-beta (IL-beta), a 3.1-fold increase in IL-1alpha and a significant decrease in multiple chemokines as well as MMPs-1, -3 and 13. All changes in clinical signs and mediators rebounded to baseline in response to treatment in the resolution phase.

CONCLUSIONS

Stent-induced gingivitis is associated with marked, but reversible increases in IL-alphaa and IL-1beta with suppression of multiple chemokines as well as selected MMPs.

Association of systemic oxidative stress with suppressed serum IgG to commensal oral biofilm and modulation by periodontal infection

To assess the impact of systemic oxidative stress on humoral immune responses, we examined the relation between levels of serum 8-isoprostane and serum IgG antibodies against 17 microorganisms in the commensal oral biofilm among the ARIC population of community-dwelling adults (n = 4,717). Bivariately, serum 8-isoprostane was associated with age, race/center, education, smoking, serum triglycerides, and the extent of periodontal disease severity. Total IgG antibody directed to the oral biofilm was significantly associated with race/center, hypertension, triglycerides, periodontal disease severity, plaque, and serum 8-isoprostane. In multivariate models, the highest quartile of increased 8-isoprostane displayed marked reductions (44%) in biofilm IgG antibody in contrast to small increases in total IgG antibody level for the highest quartiles of oral bacterial burden or periodontal disease severity (19 and 12%, respectively; p < 0.0001). Increased 8-isoprostane was associated with decreased total IgG antibody (p < 0.0001) in subjects with or without extensive periodontal disease and/or biofilm and with suppression of IgG responses across the entire biofilm composition. Increased systemic oxidative stress is associated with a generalized decrease of serum IgG antibody responses to the oral biofilm. Levels of oral microbial burden, periodontitis severity, and smoking are, by comparison, minor modifiers of serum IgG responses to the commensal oral biofilm.

Risk factors for early post-operative psychiatric symptoms in patients undergoing epilepsy surgery for temporal lobe epilepsy

OBJECTIVE

De-novo psychiatric symptoms may develop within 3 months after a temporal lobectomy for epilepsy. The objective of this study was to identify presurgical risk factors for psychiatric symptoms.

METHODS

Twenty-seven patients who had a temporal lobectomy for epilepsy were included. Twenty-four had hippocampal sclerosis or gliosis, and three had cavernous haemagiomata. Twelve had operations on the left, and 15 on the right side. Twenty-four patients were rendered free of seizures (SZ) with loss of awareness, three had early post-operative convulsions, one continued to have habitual SZ.

RESULTS

Nine patients (33%) developed low mood, anxiety and emotional lability within 3 months after surgery. Patients with early post-operative psychiatric symptoms were younger (27.9/34.8 years, P = 0.01), and more anxious on the presurgical Hospital Anxiety and Depression Scale (12/8.44, P = 0.02) than patients without post-operative psychiatric symptoms. There was also an association between right temporal lobectomies and early post-surgical symptoms (P = 0.02 Fisher's exact test).

CONCLUSION

Potential risk factors were age, anxiety and operation on the right side. Larger studies are required to determine if these risk factors are independent.

Levels of serum interleukin (IL)-6 and gingival crevicular fluid of IL-1beta and prostaglandin E(2) among non-smoking subjects with gingivitis and type 2 diabetes

BACKGROUND

The goal of this study was to assess whether non-smoking patients with type 2 diabetes present with increased levels of local and systemic proinflammatory mediators and, if so, whether such an increase is associated with enhanced clinical gingival inflammation compared to non-smoking patients without diabetes.

METHODS

We used a cross-sectional database consisting of 725 self-reported lifelong non-smokers aged 53 to 74 years. Gingival crevicular fluid (GCF) levels of interleukin (IL)-1beta and prostaglandin E(2) (PGE(2)) and serum levels of IL-6 were measured using enzyme-linked immunosorbent assay. No participant had probing depth >3 mm. Participants with bleeding on probing (BOP) in <10% of sites were classified as healthy, whereas those with BOP in >or=10% of sites were defined as having biofilm-gingival interface (BGI) gingivitis.

RESULTS

Approximately 53% (n = 385) and 11% (n = 80) of the sample had BGI gingivitis and type 2 diabetes, respectively. The mean age-adjusted level of GCF IL-1beta was significantly elevated in the diabetic group compared to the non-diabetic group (P = 0.048), but serum IL-6 (P = 0.14) and GCF PGE(2) were not (P = 0.98). The mean GCF IL-1beta and PGE(2) levels were significantly elevated in subjects with BGI gingivitis (136.2 +/- 112.9 ng/ml and 277.2 +/- 187.2 ng/ml, respectively) compared to subjects with gingival health (95.9 +/- 82.9 ng/ml and 205.7 +/- 149.6 ng/ml, respectively), regardless of diabetic status (P <0.001 for both). However, serum IL-6 was elevated in subjects with BGI gingivitis compared to subjects with gingival health only among subjects with diabetes (2.9 +/- 3.2 pg/ml versus 1.5 +/- 1.4 pg/ml; P = 0.008). With the exception of serum IL-6 in subjects without diabetes, an increase in the levels of proinflammatory mediators was associated with increased odds of having BGI gingivitis. The associations were stronger in the diabetic group.

CONCLUSIONS

Type 2 diabetes may increase the host inflammatory response to oral biofilm, which, in turn, may exacerbate preconditions associated with gingivitis in susceptible individuals. Furthermore, systemic inflammation, as demonstrated by the increased level of serum IL-6, is associated with BGI gingivitis among non-smoking patients with diabetes.

Periodontal disease at the biofilm-gingival interface

BACKGROUND

A molecular epidemiologic study provided the opportunity to characterize the biology of the biofilm-gingival interface (BGI) in 6,768 community-dwelling subjects.

METHODS

Disease classifications and multivariable models were developed using clinical, microbial, inflammatory, and host-response data. The purpose was to identify new clinical categories that represented distinct biologic phenotypes based upon DNA checkerboard analyses of eight plaque bacteria, serum immunoglobulin G (IgG) titers to 17 bacteria, and the gingival crevicular fluid (GCF) levels of 16 inflammatory mediators. Five BGI clinical conditions were defined using probing depths (PDs) and bleeding on probing (BOP) scores. Subjects with all PDs < or = 3 mm were grouped as BGI-healthy (14.3% of sample) or BGI-gingivitis (BGI-G, 15.1%). Subjects with one or more PDs > or = 4 mm [deep lesion (DL)] were divided into low BOP (18.0%), moderate BOP (BGI-DL/MB, 39.7%), and severe BOP (BGI-DL/SB, 12.9%).

RESULTS

Subjects with BGI-G had increased levels of Campylobacter rectus-specific serum IgG levels (P = 0.01), and those with BGI-DL/SB had increased IgG levels to Porphyromonas gingivalis (P < 0.0003) and C. rectus (P < 0.01). BGI-DL/SB subjects had an excessive GCF interleukin (IL)-1beta and prostaglandin E2 response and an enhanced chronic inflammatory response with significant increases in GCF IL-6 and monocyte chemotactic peptide-1. Within BGI-DL/SB subjects, more severe pocketing and BOP were associated with higher levels of GCF IL-1beta, not higher microbial counts or plaque scores.

CONCLUSIONS

New BGI classifications create categories with distinct biologic phenotypes. The increased titers of C. rectus IgG among 68.5% of the BGI-G subjects and elevated P. gingivalis titers among BGI-DL/MB and BGI-DL/SB subjects (63.8% and 75.7%, respectively) are strongly supportive of the microbial specificity of pathogenesis for BGI categories.

Measuring mania metabolites: a longitudinal proton spectroscopy study of hypomania

OBJECTIVE

Using single-voxel proton spectroscopy we aimed to investigate changes in metabolite levels in key brain regions during hypomania and euthymia in patients with bipolar disorder (BD).

METHOD

Nine patients with a diagnosis of BD and nine age, sex, education, and handedness-matched comparison subjects underwent magnetic resonance proton spectroscopy (H(1)-MRS) using a 1.5 T magnet. Patients were assessed whilst hypomanic and euthymic. Metabolite (N-acetyl asparTate, NAA; myo-inositol, mI; choline, Cho) levels in the basal ganglia (BG), anterior cingulate cortex (AC), and frontal cortex (FC) were compared both between groups and within the patient group.

RESULTS

Multivariate analysis revealed significant complex relationships between metabolite levels and brain regions with significant differences observed both between bipolar patients (hypomanic and euthymic) and controls, and across the two mood states. Hypomanic patients had lower mean metabolite levels when averaged across the AC and FC regions, compared with the controls. They also had a smaller difference in mean metabolite levels between the BG and FC than the control group. Euthymic patients were also found to have a smaller difference in the level of NAA between the BG and AC than the control group.

CONCLUSION

This exploratory study of BD demonstrates significant differences in metabolite levels that vary both with respect to brain region and mood state. Not withstanding the confounding effects of medication and the limitation of small sample size the findings are important as they demonstrate that a longitudinal approach is a useful design especially in the context of a long-term phasic illness.

A growth in bipolar disorder?

OBJECTIVE

This case report suggests that screening of patients with psychiatric symptoms using modern neuroimaging can help identify organic causes of mental illness.

METHOD

A single case study was reported.

RESULTS

We report the case of a 25-year-old woman with a recent diagnosis of bipolar II disorder having an magnetic resonance imaging (MRI) scan as part of a research project that reveals an intraventricular brain tumour. The latter is most likely the cause of her irritability and 'hypomanic' symptoms and is defined anatomically using diffusion tensor imaging and structural and functional imaging using MRI and positron emission tomography.

CONCLUSION

The lesion in this individual case most probably produces mood symptoms by impinging upon the fornix, a component of the limbic system. However, more generally, the increase in diagnosis of bipolar disorder has to be tempered against alternate causes of similar symptoms and necessitates vigilance of potential organic mechanisms.

Efficacy of a novel PEGylated humanized anti-TNF fragment (CDP870) in patients with rheumatoid arthritis: a phase II double-blinded, randomized, dose-escalating trial

OBJECTIVE

Biological products that neutralize tumour necrosis factor alpha (TNF-alpha) are beneficial in rheumatoid arthritis (RA). We studied the effects of CDP870, a novel anti-TNF-alpha antibody fragment modified to obtain a prolonged plasma half-life ( approximately 14 days).

METHODS

Thirty-six patients were randomized in a double-blind, ascending-dose group study to a single intravenous infusion of placebo (n = 12) or 1, 5 or 20 mg/kg CDP870 (each n = 8). The patients were predominantly female (30/36), had a mean age of 56 yr and a mean duration of RA of 13 years. They had received a mean of five DMARDs or experimental therapies (with 1 month washout before the study started) and had active disease. Continuation of NSAIDs and up to 7.5 mg prednisolone daily was allowed. Following the blinded dosing period, 32 patients received a single open-label infusion of either 5 or 20 mg/kg CDP870.

RESULTS

In the blinded dosing period, 6/12 placebo patients withdrew from the study (for deteriorating RA < or =4 weeks after dosing). Two of 24 CDP870-treated patients withdrew, both in the 1 mg/kg group (for deteriorating RA or lost to follow up >4 weeks after dosing). The proportion of patients with ACR20 improvement for the per-protocol population with the last observation carried forward was 16.7, 50, 87.5 and 62.5% after 0, 1, 5 and 20 mg/kg CDP870 respectively (combined treatment effect, P = 0.012, primary analysis) at 4 weeks and 16.7, 25, 75 and 75% (P = 0.032) at 8 weeks. The proportion of patients with ACR50 improvement for the per-protocol population with the last observation carried forward was 0, 12.5, 12.5 and 50% after 0, 1, 5 and 20 mg/kg CDP870 respectively (combined treatment effect, P = 0.079) at 4 weeks and 0, 12.5, 12.5 and 50% (P = 0.079) at 8 weeks. Following the open-label dose of CDP870, similar beneficial effects were achieved.

CONCLUSION

CDP870 is effective, was very well tolerated in this small study, and has an extended duration of action following one or more intravenous doses.

Learner retention of anatomical information presented in a digital two-dimensional format versus a digital three-dimensional format

This pilot study investigated learner retention of anatomical information presented in a digital two-dimensional format versus a digital three-dimensional format. Thirty-six undergraduate art students were selected by double-blind random assignment to use one of two instructional treatments: a digital two-dimensional presentation of basic brain anatomy or a digital three-dimensional presentation of the same information. Although both groups improved from pre- to post-tests, the data revealed no significant difference in test scores between the two treatments.

Outcome in patients with idiopathic inflammatory myositis: morbidity and mortality

OBJECTIVE

To assess the long-term outcome of a cohort of 46 patients with idiopathic myositis by assessing both health status, as measured by the SF-36, and cumulative survival probability over a 20-yr follow-up period at a single rheumatology centre. Methods and results. Forty-six patients under long-term follow-up from 1978 to 1999 were identified from our database. All patients fulfilled three out of four of the Bohan and Peter criteria for myositis. We excluded those with malignancy-associated disease and those with inclusion body myositis. Twenty-three patients (50%) had adult-onset polymyositis, 14 (30.4%) had adult-onset dermatomyositis, one had childhood-onset dermatomyositis and eight (17.4%) had an overlap syndrome (associated with either systemic lupus erythematosus or rheumatoid arthritis). During the course of the disease, seven patients (15.2%) went into full remission, eight (17.4%) had monophasic illness, nine (19.6%) had a relapsing-remitting course, 16 (34.8%) had chronic progressive illness and six (13.04%) died. All patients had significantly lower SF-36 scores in all aspects of health compared with the general population (P< or =0.001). Patients with chronic progressive illness had significantly greater bodily pain (P< or =0.05, t-test) than those with a relapsing-remitting illness, but did not differ in other aspects of health. There was no significant difference in the scores in the different domains of the SF-36 between the patients with active disease and those with inactive disease (0.05<P<0.1). Six of the 46 patients died. Cumulative survival probability was calculated. The five-year survival rate was 95% and the 10-yr survival rate 83.8%.

CONCLUSION

Patients with myositis report significantly poorer health compared with the general population. Health status and disease activity are important outcome measures in the assessment of patients with myositis.

Neoadjuvant docetaxel followed by radical prostatectomy in patients with high-risk localized prostate cancer: a preliminary report

Effective treatment options for high-risk localized prostate cancer are limited. Patients at high risk for recurrence include those with biopsy Gleason scores of 8 to 10, prostate specific antigen (PSA) levels > 20 ng/mL, and clinical stage T3 disease. Docetaxel chemotherapy is active in hormone-refractory prostate cancer, either combined with estramustine or used as a single agent. To determine if systemic therapy can improve the outcome of radical prostatectomy in men with high-risk localized prostate cancer, we are undertaking a pilot phase II clinical trial of weekly docetaxel at 36 mg/m(2) for up to 6 months, followed by surgery. Patients are monitored with weekly visits, monthly digital rectal examinations, PSA measurement, and testosterone tests, and endorectal magnetic resonance imaging done at baseline, after two cycles, and again after six cycles. To date, 15 patients have been enrolled, and 70 cycles of chemotherapy have been administered. Toxicity has been mostly grade 1 in intensity, and fatigue has been the most common grade 2 toxicity reported. The primary endpoint of the trial is measurement of pathologic complete response rate, for which data are not yet available. Recruitment to the trial is ongoing.

An improved vector for high-level, consistent retroviral transgene expression in human thymocytes after competitive reconstitution from transduced peripheral blood stem cells

One problem in hematopoietic stem cell (HSC)-based gene therapy is the low-level, and often transient, transgene expression in progeny cells in vivo. Here we have evaluated retroviral vector designs for improved long-term in vivo transgene expression levels in thymocytes recovered after transplantation of gene-modified HSCs. First, several vector designs were screened in vitro by single-cell analysis of transgene marking and expression to rapidly identify optimal vectors for sensitive tracking of marked cells. Next, using one optimal vector, we show that gene-modified HSCs can competitively reconstitute thymopoiesis in SCID-hu thymus/liver mice, with transgene expression detectable on 0-40% of marked donor thymocytes. Modified vector designs (termed MSCV-SAR and MoMLV-SAR), which enhance transgene expression in primary T cells in vitro, were shown here to improve in vivo transgene expression levels per cell 12- to 14-fold (mean fluorescence intensity was 2175 for MSCV-SAR vs. 174 for LNGFRSN; %NGFR(+) donor(+) cells with high-level expression was 58% for MSCV-SAR vs. 4% for LNGFRSN). Importantly, 61% of grafts had high-level transgene expression on thymocytes with the MSCV-SAR vector versus 0% of grafts for LNGFRSN or MoMLV-SAR. Transgene expression was demonstrated in various stages of thymocyte differentiation and was consistently detected in early thymic progenitors. We suggest that the MSCV-SAR vector described here is particularly advantageous for applications requiring high-level, consistent transgene expression in a diverse repertoire of T cells derived from gene-modified HSC grafts.

The EEOC charge priority policy and claimants with psychiatric disabilities

OBJECTIVE

In June 1995 the U.S. Equal Employment Opportunity Commission (EEOC) instituted a new charge priority policy. Under the new policy, charges are classified as one of three priority levels during or immediately after intake. Only charges assigned a high priority receive a full investigation. This paper examines the effect of the charge priority policy on individuals with psychiatric disabilities who filed Americans With Disabilities Act (ADA) charges with the EEOC.

METHODS

Using data extracted from the EEOC's charge data system, the authors analyzed all 66,298 ADA claims prioritized and closed between June 1995 and March 1998. The z test for difference in proportions and the generalized estimating equations procedure were used. The primary outcome measure was the priority assignment received by ADA claimants.

RESULTS

Charges that received a high priority assignment were more likely to result in benefits for claimants. Charges filed by claimants with psychiatric disabilities were significantly less likely to be assigned a high priority than charges filed by other claimants. Claimants with psychiatric disabilities were also significantly less likely to benefit from their claims.

CONCLUSIONS

The strong relationship between being assigned high priority and receiving benefits as a result of filing a charge demonstrates the importance of accurate priority categorization. The finding that people with psychiatric disabilities are less likely than others to benefit from their claims is cause for concern, particularly given the fact that the accuracy of the charge prioritization system has not been validated.

Outcomes of employment discrimination charges filed under the Americans With Disabilities Act

OBJECTIVE

The outcomes of employment discrimination charges filed under the Americans With Disabilities Act (ADA) by individuals with psychiatric disabilities and those with other disabilities were compared.

METHODS

Data obtained from the Equal Employment Opportunity Commission (EEOC) consisted of all ADA employment claims closed as of March 31, 1998. Charges were categorized by whether they were investigated by the EEOC or by a Fair Employment Practice Agency (FEPA).

RESULTS

Of the 175,226 charges filed, 83.2 percent were closed by March 31, 1998. Of these, 15.7 percent brought some kind of benefit to charging parties, although only 1.7 percent resulted in new hires or reinstatements. Of charges investigated by FEPAs, 23.3 percent led to some benefit, compared with 11.5 percent of charges investigated by the EEOC. Of charges investigated by the EEOC, the median actual monetary benefit was $5,646, compared with $2,400 for charges investigated by FEPAs. A total of 13.6 percent of charges filed by individuals with psychiatric disabilities resulted in benefits, compared with a benefit rate of 16 percent for persons with other disabilities. The median actual monetary benefit received by persons with psychiatric disabilities was $5,000, compared with $3,500 for those with nonpsychiatric disabilities. Individuals whose charges were investigated in the first three years of ADA implementation were more likely to receive benefits than individuals whose charges were investigated more recently.

CONCLUSIONS

Most employment discrimination charges filed under the ADA do not result in benefits or a finding of reasonable cause. Outcomes for people with psychiatric disabilities do not differ substantially from those for people with other disabilities.

Different paths to justice: the ADA, employment, and administrative enforcement by the EEOC and FEPAs

Under Title I of the ADA, individuals who believe they have been subjected to disability-based employment discrimination may file an administrative charge. This article looks at who files charges; over what issues, and with what outcomes in both Equal Employment Opportunity Commission (EEOC) field offices, and state and local fair employment practice agencies (FEPAs). The data for the article are computerized records of all ADA charges filed through March 31, 1998. The data indicate that individuals who rely on a FEPA to investigate their charge have a greater likelihood of obtaining a beneficial outcome than individuals who rely on the EEOC, but proportionately more individuals receiving a beneficial outcome are likely to receive monetary benefits from the EEOC than from a FEPA. Further, those who receive beneficial outcomes will probably receive greater monetary benefits from charges investigated by the EEOC than from those investigated by a FEPA.