Identification of vaccine candidate antigens from a genomic analysis of Porphyromonas gingivalis

Porphyromonas gingivalis is a key periodontal pathogen which has been implicated in the etiology of chronic adult periodontitis. Our aim was to develop a protein based vaccine for the prevention and or treatment of this disease. We used a whole genome sequencing approach to identify potential vaccine candidates. From a genomic sequence, we selected 120 genes using a series of bioinformatics methods. The selected genes were cloned for expression in Escherichia coli and screened with P. gingivalis antisera before purification and testing in an animal model. Two of these recombinant proteins (PG32 and PG33) demonstrated significant protection in the animal model, while a number were reactive with various antisera. This process allows the rapid identification of vaccine candidates from genomic data.

An open-label, 24-week pilot study of the methyl donor betaine in Alzheimer disease patients

We investigated the safety and tolerability of betaine in patients with Alzheimer disease (AD). Betaine is an alternative methyl donor, distinct from the folate-and cobalamin-dependent conversion pathway between homocysteine and methionine. Betaine has been used successfully to reduce homocysteine levels in homocystinuria. The rationale for betaine in AD was to decrease serum homocysteine levels and to increase brain methionone and S-adenosylmethionine, both of which might delay disease progression. Hyperhomocysteinemia is a possible risk factor for AD. Eight patients with probable mild AD (7 men; mean age, 69.6 years; mean Mini-Mental State Exam score, 23.7) received oral betaine (3 g twice daily) for 24 weeks. All patients were on donepezil 10 mg/day for at least 3 months before entry and throughout the study. One patient suffered a myocardial infarction and withdrew after 6 weeks. Another patient, who completed the trial, experienced diarrhea and prostatitis. Four of the 7 patients who completed the trial were rated on the Clinician's Global Impression of Change as worse after 24 weeks. On the cognitive portion of the AD Assessment Scale, 2 patients worsened by at least five points over 24 weeks, whereas the others had changes in scores of no more than two points either way. Six of 8 patients tolerated betaine for 24 weeks without difficulty. Several patients worsened over 24 weeks, but as a pilot study without a control group, efficacy measurements cannot be interpreted. The current study provides a basis for pursuing larger controlled trials with betaine in AD. The homocysteine to S-adenosylmethionine pathway is of interest in AD therapeutics.

Prevalence of symptoms on the CERAD behavior rating scale for dementia in normal elderly subjects and Alzheimer's disease patients

The authors sought to define "abnormal" levels for total scores on the CERAD Behavioral Rating Scale for Dementia (BRSD) and for 37 BRSD items by comparing 242 patients with Alzheimer's disease (AD) and 64 normal elderly control subjects (NEC). BRSD total scores for NEC ranged as high as 52 (out of a maximum 167), and although item prevalence rates were higher for AD patients, not all of these differences were significant. Many symptoms were observed in < or = 10% of AD subjects. Lower Mini-Mental State Examination scores were not consistently associated with lower or higher levels of endorsement across all items. Over 6 and 12 months, endorsement rates were relatively stable for both groups. The authors conclude that assessment of behavior in long-term studies will be needed to quantify "abnormal" levels, and that item-level BRSD information could be important in clinical trials.

A rapid appraisal method for reviewing the effectiveness of workplace smoking policies in large and medium sized organisations

Workplace smoking policies have been developed in response to growing scientific evidence about the harmful effects of environmental tobacco smoke (ETS), increasing opposition from non-smokers, concern over escalating costs of health damage and productivity losses, and the emergence of relevant laws and codes of good practice. Much has been written on the development and implementation of workplace smoking policies, but little about their evaluation. This paper describes a rapid appraisal method for the evaluation of workplace smoking policies. The four-stage process involves rapid, focused consultation with policy makers in the workplace, appropriate risk assessment, rapid consultation with those affected by the policy and focused feedback of results for planning and ongoing monitoring. In the pilot site the existing health and safety committee members were effective informants for the identification of key issues in smoking policy. The risk assessment phase was incorporated into the main appraisal which involved a canvass of staff and others on ETS issues identified by the informants. In the final stage of the process the health and safety committee proved to be both responsive to identified need, and proactive in facilitating ongoing review of the smoking policy. It therefore proved possible to develop the rapid appraisal process for administration in a limited time frame, three months for the whole process, with the rapid canvass element being achieved within one week.

A stratified response system for the emergency management of the severely injured

A decade ago, there were justifiable criticisms of the delivery of emergency care for injured patients in accident and emergency departments in the UK. To address this, a trauma management system was developed in 1991 at Alder Hey Hospital, Liverpool. This includes a trauma team, communication system, management guidelines and quality assurance. On admission to the accident and emergency department, injured patients are triaged to one of three levels of injury severity, and a multidisciplinary team lead by a paediatric surgeon or senior accident and emergency department physician is activated. The level of injury severity determines the composition of the trauma team. A care pathway based on ATLS/APLS principles has been developed. The response process as well patient management are documented and reviewed at a monthly audit meeting. Currently, more than 80% of eligible patients are managed using the trauma system, with an over-triage rate of about 25%. Regular modifications to the trauma system since its inception in 1991 have resulted in an efficient and effective management structure. Stratification of the trauma response has minimised unnecessary use of the multidisciplinary trauma team and ensures that mobilisation and use of hospital staff and resources are tailored to the needs of the injured patient. Although developed in a specialist children's hospital, the system could be adapted for any acute hospital.

Nitric oxide mediates laminin-induced neurite outgrowth in PC12 cells

Laminin is a potent stimulator of neurite outgrowth in a variety of primary neurons and neuronal cell lines. Here, we investigate the role of nitric oxide in the signaling mechanism of laminin-mediated neurite outgrowth in the PC12 cell line. Within 8 s of exposure to laminin, PC12 cells produce nitric oxide. Peak laminin-induced nitric oxide levels reach 8 nM within 12 s of exposure to laminin and constitutive nitric oxide production is sustained for 1 min. A neurite outgrowth promoting synthetic peptide (AG73), derived from the laminin-1-alpha globular domain, also stimulated nitric oxide release. The nitric oxide synthase inhibitor, 1-NAME, prevents the formation of nitric oxide and here, 1-NAME inhibited both laminin-mediated and AG73-mediated neurite outgrowth by 88 and 95%, respectively. In contrast, C16, a synthetic peptide derived from the laminin-1-gamma chain, is shown here to promote PC12 cell attachment, but not neurite outgrowth. Interestingly, the C16 peptide did not activate nitric oxide release, suggesting that laminin-induced nitric oxide release in PC12 cells is associated only with neurite outgrowth promoting laminin domains and signals. In addition, the data here show that the nitric oxide released by PC12 cells in response to laminin is required as a part of the mechanism of laminin-mediated neurite outgrowth.

Impaired function of circulating HIV-specific CD8(+) T cells in chronic human immunodeficiency virus infection

The functional status of circulating human immunodeficiency (HIV)-specific CD8 T cells in chronically infected subjects was evaluated. By flow cytometry, only 5 of 7 subjects had detectable CD8 T cells that produced IFN-gamma after stimulation with HIV-infected primary CD4 T cells. In 2 subjects, the frequency of IFN-gamma-producing cells increased 4-fold when IL-2 was added to the culture medium; in another subject, IFN-gamma-producing cells could be detected only after IL-2 was added. IFN-gamma-producing cells ranged from 0.4% to 3% of CD8 T cells. Major histocompatibility complex-peptide tetramer staining, which identifies antigen-specific T cells irrespective of function, was used to evaluate the proportion of HIV-specific CD8 T cells that may be nonfunctional in vivo. CD8 T cells binding to tetramers complexed to HIV gag epitope SLYNTVATL and reverse transcriptase epitope YTAFTIPSI were identified in 9 of 15 and 5 of 12 HLA-A2-expressing seropositive subjects at frequencies of 0.1% to 1.1% and 0.1 to 0.7%, respectively. Freshly isolated tetramer-positive cells expressed a mixed pattern of memory and effector markers. On average, IFN-gamma was produced by less than 25% of tetramer-positive CD8 T cells after stimulation with the relevant gag or reverse transcriptase peptide. In all subjects tested, freshly isolated CD8 T cells were not cytolytic against peptide-pulsed B lymphoblastoid cell line or primary HIV-infected CD4 T-cell targets. Exposure to IL-2 enhanced the cytotoxicity of CD8 T cells against primary HIV-infected CD4 targets in 2 of 2 subjects tested. These results suggest that a significant proportion of HIV-specific CD8 T cells may be functionally compromised in vivo and that some function can be restored by exposure to IL-2.

Qualifying change: a method for defining clinically meaningful outcomes of change score computation

OBJECTIVES

To identify clinically meaningful change in longitudinal assessment.

DESIGN

A novel approach that qualifies item-level change over time by the degree to which it is clinically meaningful.

SETTING

The classification method was tested by applying it to changes over 12 months in the frequency ratings of the items of a behavioral assessment instrument that is used commonly in clinical trials with Alzheimer's disease (AD) patients.

PARTICIPANTS

Responses from a cohort of 235 well characterized, community-dwelling subjects with AD were analyzed by this method.

MEASUREMENTS

The approach allowed us to describe the proportions of items that emerged, ceased, worsened, and improved between the baseline and 12-month visits.

RESULTS AND CONCLUSIONS

One-year change in the behavioral symptoms of persons with AD was used to exemplify the methodology. This approach can be used in other populations and with other measurements and was designed for analyses of clinical trial data. This method uses item-level changes to generate global impressions of clinically meaningful change; it also facilitates the definition of change that can be used in the clinical setting.

The association between age and health literacy among elderly persons

OBJECTIVE

To examine why older age groups have worse functional health literacy.

METHODS

Home interviews were conducted with community-dwelling elderly persons (n = 2,774) to determine demographics, years of school completed, newspaper reading frequency, chronic diseases, and health status. Participants completed the Short Test of Functional Health Literacy in Adults (S-TOFHLA, range 0-100) and the Mini Mental State Examination (MMSE).

RESULTS

Mean S-TOFHLA scores declined 1.4 points (95% CI 1.3-1.5) for every year increase in age (p < .001). After adjusting for sex, race, ethnicity, and education, the S-TOFHLA score declined 1.3 points (95% CI 1.2-1.4) for every year increase in age. Even after adjustment for performance on the MMSE, the S-TOFHLA score declined 0.9 points (95% CI 0.8-1.0) for every year increase in age (p < .001). Differences in newspaper reading frequency, visual acuity, chronic medical conditions, and health status, did not explain the lower literacy of older participants.

DISCUSSION

Functional health literacy was markedly lower among older age groups even after adjusting for differences in MMSE performance, newspaper reading frequency, health status, and visual acuity. Future studies should prospectively examine whether functional literacy declines with age and whether this is explained by declines in cognitive function.