Serum concentration of total soluble CD44 is elevated in smokers

Soluble CD44 isoforms have been reported as markers of specific malignancies and inflammatory diseases. However, recent reports suggest tobacco smoking may lead to an elevation in the circulating concentration of specific CD44 variants. We, therefore, investigated the effect of smoking status on circulating levels of total sCD44. Total soluble CD44 was measured by enzyme-linked immunosorbent assay in the serum of two age- and gender-matched groups consisting of smokers (n = 19) and non-smokers (n = 20). Smoking status was confirmed by analysis of serum cotinine. The concentration of total sCD44 was found to be significantly elevated in smokers compared with non-smokers (p = 0.025). The observation that total sCD44 concentration is raised in smokers may have relevance to the aetiology of smoking-associated diseases. The effect of smoking on sCD44 concentrations should be considered when assessing the role of sCD44 as a marker of inflammatory disease, cancer, or other disease processes.

The effect of smoking on bone healing: A systematic review

Objectives

To review the systemic impact of smoking on bone healing as evidenced within the orthopaedic literature.

Methods

A protocol was established and studies were sourced from five electronic databases. Screening, data abstraction and quality assessment was conducted by two review authors. Prospective and retrospective clinical studies were included. The primary outcome measures were based on clinical and/or radiological indicators of bone healing. This review specifically focused on non-spinal orthopaedic studies.

Results

Nine tibia studies and eight other orthopaedic studies were considered for systematic review. Of these 17 studies, 13 concluded that smoking negatively influenced bone healing.

Conclusions

Smoking has a negative effect on bone healing, in terms of delayed union, nonunion and more complications.

Cultivation of a Synergistetes strain representing a previously uncultivated lineage

Subgingival plaque samples obtained from human subjects with periodontitis, shown to include previously uncultivable members of the phylum Synergistetes, were used to inoculate Cooked Meat Medium (CMM). The presence of Cluster A (uncultivable) Synergistetes was monitored by fluorescent in situ hybridization (FISH) and quantitative PCR (Q-PCR). Cluster A Synergistetes were found to grow in CMM in co-culture with other plaque bacteria and growth was stimulated by the addition of mucin and serum. Plaque samples were also used to inoculate Blood Agar (BA) plates and growth of Cluster A Synergistetes was revealed after anaerobic incubation, by colony hybridization with specific probes. Surface growth on the plates in regions identified by colony hybridization was harvested and used to inoculate fresh plates, thus enriching for Cluster A Synergistetes. Cross-streaks of other plaque bacteria were also used to stimulate Synergistetes growth. In the early passages, no discrete Synergistetes colonies were seen, but after eight passages and the use of cross-streaks of other bacteria present in the enriched community, colonies arose, which consisted solely of Cluster A Synergistetes cells, as determined by 16S rRNA gene PCR and cloning. This is the first report of the successful culture of a member of the uncultivable branch of this phylum.

Periodontal Disease: Production of volatile sulphur compounds in diseased periodontal pockets is significantly increased in smokers

OBJECTIVE

This study was undertaken in order to test the hypothesis that the consequences of tobacco smoking may include increased synthesis of toxic volatile sulphur compounds in diseased periodontal pockets.

DESIGN

A cross-sectional, parallel study comparing groups of smokers and non-smokers with periodontitis and the level of volatile sulphur compounds in the gingival sulci of these subjects.

PATIENTS AND METHODS

Levels of volatile sulphur compounds were measured in diseased periodontal sites of 12 smokers and 11 non-smokers using a portable sulphide monitor. Anaerobic and aerobic counts of the total cultivable subgingival microflora of both groups were also determined.

RESULTS

The percentage of sites per subject with high levels of sulphides (> or = 10 units) detected in moderate (4-6 mm) and deep (> or = 7 mm) periodontal pockets was found to be significantly higher in smokers, compared to non-smokers (P = 0.040 and P = 0.005, respectively). No significant difference in the microbiological parameters tested were observed between the two groups.

CONCLUSIONS

Increased production of volatile sulphur compounds may represent a further mechanism of increased susceptibility to periodontitis in smokers and also help to explain the reported association between smoking and halitosis.

Immediate and early replacement implants and restorations

There have been rapid developments in dental implant treatment protocols to reduce the time between implant placement and restoration. Implants may be placed immediately following tooth extraction or following a period of healing to allow resolution of residual infection or sufficient bone and soft tissue healing. Early restoration and loading of implants has to be carefully controlled to avoid increased failure and complications. Advantages and disadvantages of the various techniques are described.

The management of developmentally absent maxillary lateral incisors – a survey of orthodontists in the UK

OBJECTIVE

To investigate the orthodontic management of patients with developmentally absent maxillary lateral incisors.

MATERIALS AND METHODS

A questionnaire was mailed to all orthodontists on the specialist list held by the British Orthodontic Society.

RESULTS

The questionnaires (57.3% response) were analysed in two groups: Group 1 consisted of orthodontists who worked only in an orthodontic practice environment; Group 2 consisted of orthodontists who worked full-time or part-time in an environment where there were restorative dentists available for advice. Group 1 orthodontists were significantly more likely to recommend (p = 0.006) space closure in the management of developmentally absent maxillary lateral incisors. Group 2 orthodontists were significantly more likely to recommend (p = 0.004) minimal preparation bridges. Group 2 orthodontists also saw significantly more patients with hypodontia (p <or=0.001) and were significantly more likely to routinely obtain a restorative dentistry opinion before orthodontic treatment commenced (p = 0.001). Group 1 orthodontists were significantly more likely to assess the space required for implants by measurement between the crowns of adjacent teeth (p = 0.001). Group 2 orthodontists were significantly more likely to assess the space by use of intraoral radiographs (p = 0.019) or by measurement between teeth at the gingival margin (p = 0.029).

CONCLUSIONS

The management of developmentally absent maxillary lateral incisors by orthodontists in the UK appeared to be influenced by their practice environment, their experience and the availability of restorative dentistry advice. The influence of these factors was greater for the treatment options of space closure or replacement via resin-retained bridges but less so for implant treatment. This reinforces the need for multidisciplinary involvement.

Astra Tech single-tooth implants: an audit of patient satisfaction and soft tissue form

AIM

To investigate patient centred outcomes, soft tissue morphology, and bone levels.

MATERIAL AND METHODS

Sixty-six subjects, who had completed treatment for a single implant restoration at least l year previously. Appearance was recorded photographically and bone levels and interdental contact points measured from intra-oral radiographs using a x 7 scale loupe. Subjects completed a satisfaction questionnaire.

RESULTS

Subjects were highly satisfied with all aspects of the restoration including the appearance of the soft tissue (median shape/colour score 6 on scale 1-6). Twenty-eight sites in 20 subjects had no contact point between implant crown and adjacent tooth. A normal height papilla was judged to be present in 19 of these sites. These were excluded from the subsequent analysis. In the remaining 46 subjects with contact points the presence (JEMT score 3) or deficiency (score 1/2) of the papilla was significantly related to the distance to the bone level on the adjacent tooth and implant head. Differences were observed between the mesial and distal aspects of the implant restoration.

CONCLUSIONS

Examining clinicians were more critical of the restorations than the patients. The presence of a complete papilla was associated with a slightly greater distance from contact point to bone level than previously reported.

Management of smoking patients by specialist periodontists and hygienists in the United Kingdom

OBJECTIVE

To assess the management of patients who are current smokers in dental practice.

MATERIALS AND METHODS

A postal questionnaire to the 243 periodontists on the UK specialist register and 239 randomly selected hygienists on the General Dental Council register.

RESULTS

Eighty per cent of both groups responded. There were significant demographic differences between the two groups of respondents: 88% of periodontists were in specialist practice and/or hospital or university departments, while 89% of hygienists were in general dental practice. Periodontists routinely asked their patients about smoking 99% of the time, hygienists 89%. More than 5 min. was spent advising a smoker patient by 35% of periodontists and 19% of hygienists. A proportion of both groups claimed to have had some recognized training in quit smoking (44% and 39%). When asked about the oral conditions of their smoking patients, 26% of periodontists stated that these patients did not have poorer oral hygiene, while 67% of hygienists thought that they did. While the majority of both groups discussed the oral effects of smoking, less than two-thirds discussed methods of giving up.

CONCLUSION

Both periodontists and hygienists are generally aware of the problems of treating smokers, and accordingly ask and advise their patients. However, lack of time and poor patient response may inhibit active involvement in assisting patients to quit smoking.

A Clinical, Radiographic, and Microbiologic Comparison of Astra Tech and Brånemark Single Tooth Implants

BACKGROUND

The soft tissues around single tooth implants differ fundamentally from the gingiva around natural teeth. There are very limited data comparing soft tissues around different implant systems.

AIM

To assess whether the design characteristics of dental implants, particularly the implant-abutment junction, may affect the dimensions and health of the peri-implant soft tissues and radiographic bone levels.

SUBJECTS AND METHOD

Fifteen Astra Tech and 15 Brånemark single tooth implants that had been in function for a minimum of 2 years in 30 partially dentate subjects were examined for plaque accumulation, probing depth, and bleeding on probing and compared to contralateral healthy teeth. Standardized radiographs were taken to measure the most coronal bone to implant contact on the mesial and distal surfaces. In addition, samples of subgingival plaque were taken on paper points and examined by darkfield microscopy.

RESULTS

Significantly higher mean probing depths (p < .001) and higher mean percentage of spirochetes (p = .003) were found at implants compared to teeth. In this sample, the Brånemark implants had significantly higher probing depths than the Astra Tech implants (median and interquartile range: Astra Tech 2.7 mm [2-3], Brånemark 3.3 mm [3-3.7] p = .026) and the most coronal bone to implant contact was closer to the implant-abutment junction in the Astra Tech implants (Astra Tech 0.6 mm [0.2-0.9], Brånemark 1.6 mm [1.4-2.0]. p < .001).

CONCLUSION

Although there were statistically significant differences between the two implant systems, the clinical differences were small and probably reflect differences in the biologic width in relation to the location and design of the implant-abutment junction.

Breakaway forces of flat and domed surfaced Magfit implant magnet attachments

The aim of this in vitro study was to compare the resistance to separation (breakaway force) of flat (Magfit-IP-BF) and domed (Magfit-IP-BD) implant magnet attachments subjected to non-axial forces. The separating forces were applied by an Instron Universal Testing Instrument to single magnet attachments at angles of 0 degrees, 2 degrees, 5 degrees 10 degrees, and 20 degrees from the axial line of the components (angle of pull) and at crosshead speeds of 0.5 mn/min and 5 degrees mm/min. The breakaway forces were significantly (p < 0.0001) inversely related to the angle of pull for both flat magnets and for domed magnets. At the slow crosshead speed, the breakaway forces recorded for the domed magnets were significantly greater than those recorded for the flat magnets for angles of pull greater than 5 degrees. At the faster crosshead speed, the breakaway forces recorded for the domed magnets were significantly greater than those recorded for the flat magnets for angles of pull greater than 2 degrees. This apparent superiority of domed magnets under non-axially directed separating forces could influence the choice of magnet attachment for implant overdentures as intraoral displacing forces are multidirectional. Domed magnets may also be advantageous where implants are not parallel.

Atypical anxiolytic-like response to naloxone in benzodiazepine-resistant 129S2/SvHsd mice: role of opioid receptor subtypes

RATIONALE

Mice of many 129 substrains respond to environmental novelty with behavioural suppression and high levels of anxiety-like behaviour. Although resistant to conventional anxiolytics, this behavioural phenotype may involve stress-induced release of endogenous opioids.

OBJECTIVES

To assess the effects of opioid receptor blockade on behavioural reactions to novelty stress in a chlordiazepoxide-resistant 129 substrain.

MATERIALS AND METHODS

Experiment 1 contrasted the effects of the broad-spectrum opioid receptor antagonist naloxone (1.0-10.0 mg/kg) in C57BL/6JOlaHsd and 129S2/SvHsd mice exposed to the elevated plus-maze. Experiments 2-4 examined the responses of 129S2/SvHsd mice to the mu-selective opioid receptor antagonist beta-funaltrexamine (2.5-10.0 mg/kg), the delta-selective antagonist naltrindole (2.5-10.0 mg/kg) and the kappa-selective antagonist nor-binaltorphimine (2.5-5.0 mg/kg).

RESULTS

129 mice displayed higher levels of anxiety-like behaviour and lower levels of general exploration relative to their C57 counterparts. Although naloxone failed to alter the behaviour of C57 mice, both doses of this antagonist produced behaviourally selective reductions in open-arm avoidance in 129 mice. Surprisingly, none of the more selective opioid receptor antagonists replicated this effect of naloxone: beta-funaltrexamine was devoid of behavioural activity, naltrindole suppressed rearing (all doses) and increased immobility (10 mg/kg), while nor-binaltorphimine (5 mg/kg) nonspecifically increased percent open arm entries.

CONCLUSIONS

Recent evidence suggests differential involvement of opioid receptor subtypes in the anxiolytic efficacy of diverse compounds including conventional benzodiazepines. The insensitivity of 129 mice to the anxiolytic action of chlordiazepoxide, coupled with their atypical anxiolytic response to naloxone (but not more selective opioid receptor antagonists), suggests an abnormality in anxiety-related neurocircuitry involving opioid-GABA interactions.

Novel subgingival bacterial phylotypes detected using multiple universal polymerase chain reaction primer sets

INTRODUCTION

Molecular ecological analysis based on 16S rRNA gene sequence analysis is well established for the characterisation of complex bacterial communities. However, 'universal' PCR primers can introduce biases into the analysis of the species composition of clone libraries because of mismatches between the primer and target organism sequences. In this study, three universal primer sets were compared for the analysis of the microflora in subgingival plaque.

METHODS

Three subgingival plaque samples were collected from two subjects with localised severe chronic periodontitis. Half of each sample was cultured while DNA was extracted from the remaining half and 16S rDNA amplified with universal primer pairs 27F, 1525R (A); 27F, 1492R (B) and 530F, 1525R (C). Amplified genes were cloned, sequenced and identified by comparison with 16S rRNA databases.

RESULTS

137 taxa were identified among 177 isolates and 417 clones sequenced. Of these, 86 were detected only by the molecular technique whereas 26 were found only by culture. Sequences from 81 taxa did not correspond to those of named species and of these, 38 were not represented in the nucleotide databases. 16S RNA genes for these 38 taxa were sequenced and deposited with GenBank.

CONCLUSION

The use of three sets of universal primers allowed the identification of 38 novel bacterial phylotypes. There were marked differences in the composition of the libraries generated by the different primer sets. A combination of molecular and cultural techniques is recommended to maximise the coverage of detection of bacterial taxa in oral samples.

A retrospective study of periodontal disease severity in smokers and non-smokers

BACKGROUND

Smoking has been associated with increased risk of periodontitis. The aim of the present study was to compare the periodontal disease severity of adult heavy smokers and never-smokers referred for assessment and treatment of chronic periodontitis.

METHODS

A random sample of patients with at least 20 teeth, stratified for smoking and age (5-year blocks, 35 to 55 years), was selected from an original referral population of 1,221 subjects with chronic adult periodontitis. Adequate records for 59 never-smokers and 44 subjects who smoked at least 20 cigarettes per day were retrieved. The percentage of alveolar bone support was measured from dental panoramic radiographs with a Schei ruler at x3 magnification with the examiner unaware of the smoking status. Probing depths at six sites per tooth were obtained from the initial consultation.

RESULTS

There was no significant difference in age between groups. Smokers had fewer teeth (p<0.001), fewer shallow pockets (p<0.001) and more deep probing depths (p<0.001). The differences were greater in subjects 45 years of age and over. In this age group, smokers had approximately 13% more bone loss, 15% more pockets in the 4-6 mm category and 7% more pockets in the >/= 7 mm category than the never-smokers.

CONCLUSIONS

This study confirmed that smokers had evidence of more severe periodontal disease than never-smokers. The differences increased with age confirming an exposure-related response.

A prospective 3-year study of fixed bridges linking Astra Tech ST implants to natural teeth

BACKGROUND

Connecting teeth and osseointegrated implants in fixed reconstructions is not generally recommended because of differences in their response to loading.

AIM

The aim of the present study was to assess the clinical and radiographic performance of the teeth and implants used to support three unit fixed bridges subjected to normal functional loads.

SUBJECTS AND METHODS

Nineteen subjects (10 males, nine females, age range 27-65 years) with an edentulous posterior free end saddle in either maxilla or mandible (Kennedy Class 2), and opposing natural teeth or a tooth-supported fixed bridge were treated and completed the 3-year trial. An Astra Tech ST implant (length: 9 mm (n=2), 11 mm (n=9) or 13 mm (n=8); diameter: 4.5 mm) was placed immediately distal to the last tooth or leaving a single premolar sized space. The distal tooth received a gold coping and the implant was restored with a customised Prepable abutment (Astra Tech Profile BiAbutment: diameter 5.5 or 7 mm). A fixed bridge was placed linking the gold coping and implant abutment either with the pontic as a distal cantilever (n=6, length 7-8 mm) or as a fixed-fixed design (n=13, length 6-12 mm). Standardised radiographs and clinical records were taken at delivery of the prosthesis (baseline BL) and annually.

RESULTS

Plaque scores at implant sites increased between BL and subsequent years (P<0.02). Statistically significant increases in probing depth were observed at both abutment teeth and implants between baseline and subsequent years (P<0.001). Marginal bone levels (mm) at the implant and tooth were stable between BL, 1-, 2- and 3-year examinations (implant: BL 0.65+/-0.42, 1 year 0.63+/-0.47, 2 years 0.88+/-0.55, 3 years 0.78+/-0.64; tooth: BL 2.29+/-0.82, 1 year 2.41+/-0.8, 2 years 2.38+/-1.02, 3 years 2.68+/-0.86). No signs of the intrusion of the abutment teeth were detected. One case of abutment screw loosening occurred. Eight bridges required re-cementation with a permanent cement in place of the temporary cement. There were eight subjects presenting with fractures/chips to the composite component of the bridges.

CONCLUSION

The 3-year results demonstrate fully functional successful restorations with no evidence of tooth intrusion and with stable bone levels at both teeth and implants.

The influence of vitamin C on systemic markers of endothelial and inflammatory cell activation in smokers and non-smokers

OBJECTIVE AND DESIGN

To determine the influence of vitamin C supplementation (500 mg, bd, 14 days) on the circulating concentrations of soluble ICAM-1 (a marker of endothelial activation), neopterin (a marker of monocyte activation), and neutrophil elastase (a marker of neutrophil activation) in smokers and non-smokers in a randomised, double-blind, placebo-controlled trial in a hospital setting.

SUBJECTS

Twenty smokers (serum cotinine > or = 20 ng ml(-1)) and 20 age- and gender-matched non-smokers (serum cotinine < or = 13.7 ng ml(-1)).

RESULTS

At baseline, there was a significant elevation in the concentration of sICAM-1 in smokers (median 247, IQR 199 to 357 ng ml(-1)) compared to non-smokers (median 207, IQR 189 to 227 ng ml(-1); p = 0.014). Vitamin C supplementation did not influence the circulating concentrations of ICAM-1 or neopterin, or leukocyte elastase activity, in smokers, non-smokers, or in the total population.

CONCLUSIONS

Markers of monocyte and neutrophil activation were not influenced by smoking status in this study population. However, sICAM-1 concentrations were significantly elevated in tobacco smokers, reflecting tobacco-induced vascular activation that is unaffected by Vitamin C supplementation.

Evaluation of a new periodontal probe tip design. A clinical and in vitro study

AIMS

In the search for an accurate periodontal probe which does not frequently penetrate the pocket base, a new tip has been designed which is flattened, and of 1 mm width and 0.45 mm thickness. This study aimed to evaluate the physico-mechanical and clinical properties of this probe (test) in comparison to a conventional 0.5 mm circular probe (control).

METHODS

Photoelastic stress analysis was undertaken for test and control probe tips at 3.15 and 5 N loads. To assess probing validity, the clinical probing depth with each probe (0.25 N force) at 125 sites on 27 teeth (27 subjects), was compared with the post-extraction connective tissue level measurement. Also evaluated were probing reproducibility (1200 sites in 25 subjects) and patient comfort (30 subjects).

RESULTS

Using photoelastic stress analysis, the test probe demonstrated lower stresses and less local stress concentration than the control. Clinically, the test probe measured close to the post-extraction gold standard in greater frequency than the control - 26 versus 11 readings (21% versus 9%) exactly matched, and 90 versus 67 (72% versus 54%) were within +/-0.5 mm of the laboratory measurement. The test probe was, on average, 0.13 mm coronal to the connective tissue attachment level, whereas the control penetrated 0.27 mm past this level. The intraclass correlation between clinical and laboratory readings was greater for the test than the control (r=0.81 and 0.74, respectively). Although the control probe overestimated probing depth more markedly at bleeding (0.41 mm) than at non-bleeding (0.15 mm) sites, the relative position of the test probe hardly differed with inflammatory status (-0.11 and -0.14 mm, respectively). Each probe demonstrated good clinical reproducibility. However, the test probe examination was more comfortable for the patient.

CONCLUSION

This new periodontal probe tip appears to have greater validity, good reproducibility and produces less patient discomfort.

The longitudinal accuracy of fit of titanium implant superstructures superplastically formed on investment models

OBJECTIVES

To measure the effect of three special liquid proportions and five forming temperatures on the length of superplastically formed titanium dental implant superstructures made using Rematitan dental casting investment.

METHODS

Rematitan dental casting investment was used to make models that contained two implant abutment analogues 8 mm apart. The investment was hand-mixed with 30, 50 or 70% special liquid proportions and ten models of each were made. Dies for superplastic forming (SPF) were made that contained three models (one for each special liquid proportion). Five dies were made for forming at 810 degrees C and five dies for forming at 810, 840, 873, 900 and 927 degrees C using 2 mm thick Ti-6Al-4V discs. The distance between the abutment impressions in the formed discs was measured with a traveling microscope and compared with the distance between the abutments of the master model to determine the most accurately fitting superstructure beam.

RESULTS

The proportion of special liquid used to make the SPF models had an unpredictable effect on the length of the superstructure at each forming temperature. Superstructure beams formed at lower temperatures had a better fit compared to the master model for all special liquid proportions. The most accurately sized beams were formed at 810 degrees C.

SIGNIFICANCE

SPF can provide an alternative method for the production of dental implant superstructures. The fit was affected predominantly by the forming temperature, but also by the special liquid proportion used for making the SPF investment model.

Gingival bleeding on probing increases after quitting smoking

BACKGROUND

Gingival inflammation associated with plaque accumulation is delayed or impaired in smokers. Anecdotal evidence suggests that smokers who quit experience an increase in gingival bleeding.

METHOD

A group of 27 subjects on a Quit-smoking programme were examined for changes in gingival health over a 4-6-week period.

RESULTS

The bleeding on probing with a constant force probe increased from 16% of sites to 32% of sites, despite improvements in the subjects oral hygiene.

CONCLUSION

This provides further evidence that tobacco smoking affects the inflammatory response and that these changes are reversible on quitting.

Analysis of two common alpha 1-antitrypsin deficiency alleles (PI*Z and PI*S) in subjects with periodontitis

BACKGROUND

pi alpha 1-Antitrypsin deficiency is a genetically determined condition resulting in predisposition to certain inflammatory diseases due to a protease: antiprotease imbalance that is exacerbated by tobacco smoking. Limited evidence suggests that there may be a significant enrichment of mild alpha 1-antitrypsin deficiency phenotypes in subjects with chronic inflammatory periodontal disease.

OBJECTIVE

To examine the prevalence of two common alpha1-antitrypsin deficiency alleles (PI*Z and PI*S) in a UK population of subjects with periodontitis.

SUBJECTS AND METHODS

The prevalence of PI*M, PI*S and PI*Z allele combinations was determined in 31 subjects with periodontitis and compared with 31 healthy control subjects matched for smoking status, ethnicity, age and gender. alpha 1-Antitrypsin genotyping was performed by multiplex real-time fluorescence polymerase chain reaction (PCR) using DNA extracted from whole blood.

RESULTS

There was no difference in the proportion of any alpha 1-antitrypsin genotype found in the diseased and control populations.

CONCLUSIONS

We did not find evidence to support an association between mutant PI* alleles and periodontitis in a small, controlled study. Larger studies will be required to clarify the relationship between alpha1-antitrypsin genotype and susceptibility to inflammatory periodontal disease.

Effect of nicotine replacement and quitting smoking on circulating adhesion molecule profiles (sICAM-1, sCD44v5, sCD44v6)

BACKGROUND

Soluble ICAM-1 (sICAM-1; sCD54), sCD44v5 and sCD44v6 are circulating adhesion molecules, with immunomodulatory potential, that have been frequently attributed diagnostic, prognostic and aetiological significance in a number of inflammatory and malignant diseases. We have previously shown that systemic concentrations of these molecules are increased significantly in tobacco smokers, but reduce to within normal levels at 12 months following successful quitting.

MATERIALS AND METHODS

We have been able to extend these observations by measuring levels before and 4, 8, 22 and 52 weeks after smoking cessation in subjects receiving high-dose nicotine replacement therapy (25 mg of nicotine; n = 34) or placebo patches (n = 34) for 26 weeks. Smoking cessation was confirmed by regular measurement of expired-air CO levels and by plasma cotinine analysis.

RESULTS

Plasma sICAM-1, sCD44v5 and sCD44v6 concentrations all declined rapidly within 4 weeks of smoking cessation (P < 0.001 for all declines). Additionally, no differences were observed between those using nicotine replacement and those who were not for sICAM-1, sCD44v5, or sCD44v6.

CONCLUSIONS

The recovery in smoking-associated adhesion molecule profiles represents an almost immediate beneficial effect of smoking cessation. Nicotine replacement therapy is an effective aid to quitting and does not affect these recoveries. The elevated levels of these important risk factors in smokers (sICAM-1, sCD44v5 and sCD44v6) are linked to noxious element(s) in tobacco smoke other than nicotine or nicotine metabolites.

Analysis of circulating insulin-like growth factor-1 (IGF-1) and IGF binding protein-3 (IGFBP-3) in tobacco smokers and non-smokers

BACKGROUND

IGF-1 and the major serum IGF-1 binding protein, IGFBP-3, are under extensive investigation as potential prognostic markers of specific malignancies and vascular diseases. However, there is conflicting evidence that tobacco smoking may influence systemic concentrations of IGF-1 and IGFBP-3.

SUBJECTS AND METHODS

Serum concentrations of IGF-1 and IGFBP-3 were measured in 20 smokers and 20 non-smokers, matched for age and gender. Serum concentrations of cotinine, the major metabolite of nicotine, and ICAM-1, known to exhibit a dose-dependent relationship with cotinine, were also assayed.

RESULTS

There was no difference between the systemic concentrations of IGF-1 or IGFBP-3 found in smokers and non-smokers (IGF-1: mean [s.d]; 104 29 vs 101 24 ng ml-1, respectively; and IGFBP-3: 2562 [522] vs 2447 [570] ng ml-1, respectively). Similarly, there was no correlation between serum cotinine and IGF-1 or IGFBP-3 concentrations in smokers. Soluble ICAM-1 concentrations were significantly increased in smokers, compared to non-smokers (mean [s.d]; 258 [60] vs 194 [50] ng ml-1, respectively; p = 0.002).

CONCLUSION

There was no relationship noted between tobacco smoking and either IGF-1 or IGFBP-3. These data suggest that smoking would not appear to be a major confounder of the reported clinical associations between IGF-1, IGFBP-3, or IGF-1/IGFBP-3 ratios and specific disease entities.

The influence of tobacco smoking on adhesion molecule profiles

Sequential interactions between several adhesion molecules and their ligands regulate lymphocyte circulation and leukocyte recruitment to inflammatory foci. Adhesion molecules are, therefore, central and critical components of the immune and inflammatory system. We review the evidence that tobacco smoking dysregulates specific components of the adhesion cascade, which may be a common factor in several smoking-induced diseases. Smoking causes inappropriate leukocyte activation, leukocyte-endothelial adhesion, and neutrophil entrapment in the microvasculature, which may help initiate local tissue destruction. Appropriate inflammatory reactions may thus be compromised. In addition to smoke-induced alterations to membrane bound endothelial and leukocyte adhesion molecule expression, which may help explain the above phenomena, smoking has a profound influence on circulating adhesion molecule profiles, most notably sICAM-1 and specific sCD44 variants. Elevated concentrations of soluble adhesion molecules may simply reflect ongoing inflammatory processes. However, increasing evidence suggests that specific soluble adhesion molecules are immunomodulatory, and that alterations to soluble adhesion molecule profiles may represent a significant risk factor for several diverse diseases. This evidence is discussed herein.

Expression of ICAM-1 and E-selectin in gingival tissues of smokers and non-smokers with periodontitis

BACKGROUND

Tobacco smoking affects systemic concentrations of soluble intercellular adhesion molecule (ICAM)-1, but its effect on local expression of adhesion molecules in gingival tissue has not been studied previously.

METHODS

E-selectin and ICAM-1 expression on small blood vessel endothelia in gingival biopsies obtained from smokers (n=17) and non-smokers (n=17) with periodontitis was examined with immunohistochemistry. Blood vessels were identified with monoclonal antibody for von Willebrand's factor.

RESULTS

A significantly larger number of vessels were observed in inflamed tissues of non-smokers than smokers (P<0.05). The number and proportion of vessels expressing both ICAM-1 and E-selectin was greater in sites with inflammation compared to non-inflamed sites in both smokers and non-smokers (P<0.05). The proportion of the total number of vessels expressing ICAM-1 in non-inflamed sites was greater in non-smokers compared with smokers (P<0.05).

CONCLUSIONS

These results suggest that the inflammatory response in smokers with periodontitis may not be accompanied by an equivalent increase in vascularity. Reduced ICAM-1 expression in non-inflamed areas of smokers could reflect a systemic effect of tobacco smoking on ICAM-1 independent of inflammation.

Outcomes following physical restraint reduction programs in two acute care hospitals

BACKGROUND

Physical restraint rates can be reduced safely in long term care settings, but the strategies used to prevent wandering, falls, and patient aggression have not been tested for their effectiveness in preventing therapy disruption. A restraint reduction program (RRP) consisting of four core components (administrative, educational, consultative, and feedback) was implemented in 1998-1999 in 14 units at two acute care hospitals in geographically distant cities.

METHODS

The RRP was targeted at units with prevalence rates of > or = 4% for non-intensive care units (non-ICUs) and > or = 25% for ICUs, as well as two additional units. The RRP was implemented by an interdisciplinary team consisting of geriatricians and nurse specialists.

RESULTS

Of the 16,605 admissions to the RRP units, 2,772 cases received RRP consultations. Only six units (four of seven general units and two of six ICUs) demonstrated a relative reduction of > or = 20% in the physical restraint use rate. No increase in secondary outcomes of patient falls and therapy disruptions (patient-initiated discontinuation or dislodgment of therapeutic devices) occurred, injury rates were low, and no deaths occurred as a direct result of either a fall or therapy disruption event.

DISCUSSION

Given the minimal success in the ICU settings, further studies are needed to determine effective nonrestraint strategies for critical care patients. ICU clinicians need to be persuaded of the favorable risk-to-benefit ratio of alternatives to physical restraint before they will change their practice patterns.

SUMMARY

Efforts to identify more effective interventions that match patient needs and to identify non-clinician factors that affect physical restraint use are needed.

Establishing a case-finding and referral system for at-risk older individuals in the emergency department setting: the SIGNET model

Older emergency department (ED) patients have complex medical, social, and physical problems. We established a program at four ED sites to improve case finding of at-risk older adults and provide comprehensive assessment in the ED setting with formal linkage to community agencies. The objectives of the program are to (1) improve case finding of at-risk older ED patients, (2) improve care planning and referral for those returning home, and (3) create a coordinated network of existing medical and community services. The four sites are a 1,000-bed teaching center, a 700-bed county teaching hospital, a 400-bed community hospital, and a health maintenance organization (HMO) ED site. Ten community agencies also participated in the study: four agencies associated with the hospital/HMO sites, two nonprofit private agencies, and four public agencies. Case finding is done using a simple screening assessment completed by the primary or triage nurse. A geriatric clinical nurse specialist (GCNS) further assesses those considered at risk. Patients with unmet medical, social, or health needs are referred to their primary physicians or to outpatient geriatric evaluation and management centers and to community agencies. After 18 months, the program has been successfully implemented at all four sites. Primary nurses screened over 70% (n = 28,437) of all older ED patients, GCNSs conducted 3,757 comprehensive assessments, participating agency referrals increased sixfold, and few patients refused the GCNS assessment or subsequent referral services. Thus, case finding and community linkage programs for at-risk older adults are feasible in the ED setting.

Validation of smoking status in clinical research into inflammatory periodontal disease

BACKGROUND

Tobacco smoking is an accepted risk factor for periodontal disease. Most studies in the periodontal literature rely on reported smoking habits which can be unreliable. This review specifically addresses this problem.

METHODS

Methods of assessing tobacco smoke exposure, variation in individual smoking habits, classification of former/ex-smokers, and validation of abstinence in smoking cessation studies receive attention.

DISCUSSION

Additionally, clinical studies that have examined periodontal health in subjects with validated smoking status are discussed.

Comparison of the validity of periodontal probing measurements in smokers and non-smokers

AIM

To determine whether the reduced inflammation and bleeding and increased fibrosis reported in tobacco smokers affect the validity of clinical probing measurements by altering probe tip penetration.

METHOD

A constant force probe was used to measure probing depths and sound bone levels at six sites on 64 molar teeth (384 sites) in 20 smoking and 20 non-smoking patients from grooves made with a bur at the gingival margin prior to extraction. Connective tissue attachment levels were measured from the grooves with a dissecting microscope following extraction. Data were analysed using robust regression with sites clustered within subjects.

RESULTS

Sites in smokers showed more calculus but less bleeding than sites in non-smokers (p<0.05). The mean clinical probing depth was not significantly different (smokers: 5.54 mm, confidence intervals=4.81 to 6.28; non-smokers: 6.05 mm, ci=5.38 to 6.72). The corresponding post-extraction pocket depth measurements (smokers: 4.95 mm, ci=4.30 to 5.61; non-smokers: 5.23 mm, ci=4.49 to 5.96) were less than clinical probing depth in sites from both smokers and non-smokers (p<0.01). However, the proportional difference was less in smokers (p<0.05), particularly in deeper pockets, indicating that clinical probe tip penetration of tissue was greater in non-smokers. Regression analysis indicated that the presence of calculus and bleeding also influenced the difference in clinical probe penetration (p<0.05).

CONCLUSION

Clinical probing depth at molar sites exaggerates pocket depth, but the probe tip may be closer to the actual attachment level in smokers due to less penetration of tissue. This may be partly explained by the reduced inflammation and width of supra-bony connective tissue in smokers. These findings have clinical relevance to the successful management of periodontal patients who smoke.

Elevated systemic concentrations of soluble ICAM-1 (sICAM) are not reflected in the gingival crevicular fluid of smokers with periodontitis

Raised serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) in smokers could have immunomodulatory effects in periodontitis. The aim of this study was to compare serum and gingival crevicular fluid (GCF) concentrations of sICAM-1 in smokers and non-smokers with periodontal disease. sICAM-1 in serum and GCF collected from age- and gender-matched smokers (n = 14) and non-smokers (n = 14) with periodontitis were measured by ELISA. Mean serum sICAM-1 concentrations were significantly elevated in smokers (331 ng mL(-1)), compared with non-smokers (238 ng mL(-1), p = 0.008). However, the concentration of sICAM-1 in the GCF was significantly lower in the smokers (83 ng mL(-1)), compared with non-smokers (212 ng mL(-1), p = 0.013). The difference between concentrations of sICAM-1 in GCF and serum was significant only in smokers (p < 0.001). Since GCF is a serum-derived tissue exudate, these results suggest that, in smokers, circulating sICAM-1 molecules are affected either in their passage from the periodontal microvasculature or within the periodontal tissues.

Development and validation of a prognostic index for 1-year mortality in older adults after hospitalization

CONTEXT

For many elderly patients, an acute medical illness requiring hospitalization is followed by a progressive decline, resulting in high rates of mortality in this population during the year following discharge. However, few prognostic indices have focused on predicting posthospital mortality in older adults.

OBJECTIVE

To develop and validate a prognostic index for 1 year mortality of older adults after hospital discharge using information readily available at discharge.

DESIGN

Data analyses derived from 2 prospective studies with 1-year of follow-up, conducted in 1993 through 1997.

SETTING AND PATIENTS

We developed the prognostic index in 1495 patients aged at least 70 years who were discharged from a general medical service at a tertiary care hospital (mean age, 81 years; 67% female) and validated it in 1427 patients discharged from a separate community teaching hospital (mean age, 79 years; 61% female).

MAIN OUTCOME MEASURE

Prediction of 1-year mortality using risk factors such as demographic characteristics, activities of daily living (ADL) dependency, comorbid conditions, length of hospital stay, and laboratory measurements.

RESULTS

In the derivation cohort, 6 independent risk factors for mortality were identified and weighted using logistic regression: male sex (1 point); number of dependent ADLs at discharge (1-4 ADLs, 2 points; all 5 ADLs, 5 points); congestive heart failure (2 points); cancer (solitary, 3 points; metastatic, 8 points); creatinine level higher than 3.0 mg/dL (265 micromol/L) (2 points); and low albumin level (3.0-3.4 g/dL, 1 point; <3.0 g/dL, 2 points). Several variables associated with 1-year mortality in bivariable analyses, such as age and dementia, were not independently associated with mortality after adjustment for functional status. We calculated risk scores for patients by adding the points of each independent risk factor present. In the derivation cohort, 1-year mortality was 13% in the lowest-risk group (0-1 point), 20% in the group with 2 or 3 points, 37% in the group with 4 to 6 points, and 68% in the highest-risk group (>6 points). In the validation cohort, 1-year mortality was 4% in the lowest-risk group, 19% in the group with 2 or 3 points, 34% in the group with 4 to 6 points, and 64% in the highest-risk group. The area under the receiver operating characteristic curve for the point system was 0.75 in the derivation cohort and 0.79 in the validation cohort.

CONCLUSIONS

Our prognostic index, which used 6 risk factors known at discharge and a simple additive point system to stratify medical patients 70 years or older according to 1-year mortality after hospitalization, had good discrimination and calibration and generalized well in an independent sample of patients at a different site. These characteristics suggest that our index may be useful for clinical care and risk adjustment.

Dose-years as an improved index of cumulative tobacco smoke exposure

In assessing the link between tobacco smoking and disease, it is important to determine longterm, cumulative exposure to tobacco smoke as accurately as possible. Conventional methods of assessing exposure to tobacco smoke each have intrinsic limitations. Self-reporting of tobacco use, and the conversion of this data to pack-years, can be prone to error due to individuals wishing to conceal smoking habits, inaccurate reporting of daily cigarette consumptions or years of smoking, and failure to take into account the variation that exists in inter-individual smoking experiences. Measurement of cotinine, a major metabolite of nicotine in humans, is a reliable method of monitoring recent doses of tobacco smoke exposure. Cotinine concentrations, however, may remain stable in smokers over the longer term. Therefore, dose-years, and more specifically cotinine-years, may represent an improved index of cumulative tobacco smoke exposure.

The relationship of sedation to deliberate self-extubation

STUDY OBJECTIVES

To evaluate the relationship between sedative therapy and self-extubation in a large medical-surgical intensive care unit (ICU).

DESIGN

Retrospective, case-controlled study.

SETTING

Large teaching hospital.

PATIENTS

All adult patients who underwent unplanned self-extubation during a 12-month period (n = 50). Each patient was matched to two control patients who did not self-extubate based on age, gender, dates in hospital and diagnosis.

INTERVENTIONS

none.

MEASUREMENTS

Data collected included time to self extubation, dosages and types of benzodiazepines, opioid analgesics, antipsychotics, and hypnotics. Data on the degree of agitation as assessed by nursing staff also were obtained.

MAIN RESULTS

When compared to controls, patients in the self-extubation group were more likely to have received benzodiazepines (59% vs. 35%; p < 0.05), but equally likely to have received opioids and/or paralytic drugs. Patients who self-extubated were twice as likely as controls to be agitated (54% vs. 22%; p < 0.05). Use of benzodiazepines was more common in agitated patients than in nonagitated patients (62% vs. 35%; p < 0.02). Among nonagitated patients who self-extubated, increased use of benzodiazepines (57% vs. 29%; p < 0.05) was noted when compared to nonagitated controls.

CONCLUSIONS

In intubated ICU patients, benzodiazepines may not consistently treat agitation effectively or prevent self-extubation. Such an effect may be due to paradoxical excitation, disorientation during long-term administration, or differences in drug administration between ICU and operating room (OR) environments.

Effects of a multicomponent intervention on functional outcomes and process of care in hospitalized older patients: a randomized controlled trial of Acute Care for Elders (ACE) in a community hospital

BACKGROUND

Older persons frequently experience a decline in function following an acute medical illness and hospitalization.

OBJECTIVE

To test the hypothesis that a multicomponent intervention, called Acute Care for Elders (ACE), will improve functional outcomes and the process of care in hospitalized older patients.

DESIGN

Randomized controlled trial.

SETTING

Community teaching hospital.

PATIENTS

A total of 1,531 community-dwelling patients, aged 70 or older, admitted for an acute medical illness between November 1994 and May 1997.

INTERVENTION

ACE includes a specially designed environment (with, for example, carpeting and uncluttered hallways); patient-centered care, including nursing care plans for prevention of disability and rehabilitation; planning for patient discharge to home; and review of medical care to prevent iatrogenic illness.

MEASUREMENTS

The main outcome was change in the number of independent activities of daily living (ADL) from 2 weeks before admission (baseline) to discharge. Secondary outcomes included resource use, implementation of orders to promote function, and patient and provider satisfaction.

RESULTS

Self-reported measures of function did not differ at discharge between the intervention and usual care groups by intention-to-treat analysis. The composite outcome of ADL decline from baseline or nursing home placement was less frequent in the intervention group at discharge (34% vs 40%; P = .027) and during the year following hospitalization (P = .022). There were no significant group differences in hospital length of stay and costs, home healthcare visits, or readmissions. Nursing care plans to promote independent function were more often implemented in the intervention group (79% vs 50%; P = .001), physical therapy consults were obtained more frequently (42% vs 36%; P = .027), and restraints were applied to fewer patients (2% vs 6%; P = .001). Satisfaction with care was higher for the intervention group than the usual care group among patients, caregivers, physicians, and nurses (P < .05).

CONCLUSIONS

ACE in a community hospital improved the process of care and patient and provider satisfaction without increasing hospital length of stay or costs. A lower frequency of the composite outcome ADL decline or nursing home placement may indicate potentially beneficial effects on patient outcomes.

Plasma concentrations of reputed tumor-associated soluble CD44 isoforms (v5 and v6) in smokers are dose related and decline on smoking cessation

There is some evidence to suggest that smoking may affect circulating levels of CD44 (sCD44) molecules. Therefore, we investigated the effect of smoking on the circulating level of sCD44 by comparing the change in total sCD44, sCD44v5, and sCD44v6 concentrations over 1 year in a group of people who quit smoking (n = 30) and a control group of people who continued to smoke (n = 30). Smoking status and compliance were monitored by analysis of plasma cotinine and expired CO levels and also by self-reported tobacco use. We show a dose-dependent relationship between smoke intake and baseline plasma concentrations of reputed tumor-associated CD44 variant isoforms (sCD44v5 and sCD44v6) in smokers (n = 60). There was a significant decline in the level of both sCD44v5 and sCD44v6 in quitters as compared with continuing smokers [-13.2 (95% confidence interval, -7.6 to -18.8; P < 0.001) and -62.2 ng/ml (95% confidence interval, -33.9 to -90.6; P < 0.001), respectively], but not in the total sCD44 concentration. These results show that the increased concentrations of sCD44v5 and sCD44v6 in smokers are dose related and reversible and suggest that the attributed diagnostic specificity and prognostic value of sCD44 molecules in malignant and inflammatory disease may be affected by smoking status.

Circulating concentrations of C-reactive protein and total sialic acid in tobacco smokers remain unchanged following one year of validated smoking cessation

BACKGROUND

Elevated plasma concentrations of C-reactive protein (CRP) and total sialic acid (TSA) have been associated with increased cardiovascular risk. Additionally, levels of both CRP and TSA have been reported to be significantly elevated in smokers. However, it is not clear if the raised TSA and CRP levels noted in smokers are directly attributable to the smoking experience, or if they may be elevated due to a secondary mechanism(s), such as smoking-induced tissue inflammation.

SUBJECTS AND METHODS

We measured the plasma concentration of CRP and TSA in a group of smokers at baseline and following one year of validated smoking cessation (n = 30) and in a control group of tobacco users who continued to smoke over the year (n = 30).

RESULTS

The baseline concentration of TSA and CRP was 67.2 mg dL(-1) and 1.91 mg L(-1), respectively (n = 60). No significant dose-dependent relationship was noted between baseline CRP or TSA concentration and either plasma cotinine, expired-air CO or daily cigarette consumption. There was no difference in the mean change in CRP level in the quitters over one year (- 0.2 mg L(-1)) compared to the continuing smokers (+ 0.5 mg L(-1)), P = 0.80, or in the change in concentration of TSA in the quitters (- 2.7 mg dL(-1)) compared to the continuing smokers (+ 0.4 mg dL(-1)), P = 0.26.

CONCLUSIONS

As the circulating concentrations of both CRP and TSA remain unchanged following one year of smoking cessation, these results would suggest that the elevated levels noted in smokers are not directly attributable to tobacco use and are more likely to be elevated due to a secondary process that is yet to be established.

Maternal protein deficiency causes hypermethylation of DNA in the livers of rat fetuses

Maternal protein deficiency during pregnancy is associated with changes in glucose tolerance and hypertension in the offspring of rats. In this study the growth of rat fetuses was examined when the dams were fed diets containing 18% casein, 9% casein or 8% casein supplemented with threonine. The extra threonine was added to reverse the decrease in circulating threonine concentrations that occurs when pregnant rats are fed protein-deficient diets. The fetuses of the group fed the low protein diet supplemented with threonine were significantly smaller than those of the control group and not significantly different from those fed low protein. Homogenates prepared from the livers of dams fed the diet containing 9% casein oxidized threonine at approximately twice the rate of homogenates prepared from dams fed the diet containing 18% casein. We conclude that circulating levels of threonine fall as a consequence of an increase in the activity of the pathway that metabolizes homocysteine produced by the transulfuration of methionine. Serum homocysteine was unaffected in the dams fed low protein diets compared with controls, but was significantly greater in dams fed the low protein diet supplemented with threonine. Elevated levels of homocysteine are associated with changes in the methylation of DNA. The endogenous methylation of DNA was greater than that of controls in the livers of fetuses from dams fed the 9% protein diets and increased further when the diet was supplemented with threonine. Our results suggest that changes in methionine metabolism increase homocysteine production, which leads to changes in DNA methylation in the fetus. An increase in maternal homocysteine may compromise fetal development, leading to the onset of glucose intolerance and hypertension in adult life.

Dramatic decline in circulating intercellular adhesion molecule-1 concentration on quitting tobacco smoking

The concentration of soluble ICAM-1 (sICAM-1) is significantly elevated in smokers, but it is unclear if smoking is the direct cause of elevated sICAM-1 levels, if the relationship between smoking and sICAM-1 level is dose-dependent, and if smoking cessation may lead to a decline in sICAM-1. We sought to clarify the relationship between smoking and sICAM-1 in a group of smokers who quit smoking for 1 year (n = 30) and a control group who continued to smoke (n = 30). A dose-dependent relationship between plasma sICAM-1 concentration and daily cigarette consumption (P = 0.02), plasma cotinine level (P = 0.02), and expired CO level (P = 0.007) was observed at baseline (n = 60). The mean change in sICAM-1 concentration after 52 weeks was greater for quitters than for continuing smokers (mean difference = -71.1 ng/ml, P < 0.001). The influence of smoking on sICAM-1 needs to be carefully considered in clinical trials. Soluble ICAM-1 remains bioactive and may contribute to pathogenic processes; therefore, reduction in the concentration of circulating ICAM-1 molecules may directly contribute to the health benefits associated with smoking cessation.

The acute influence of tobacco smoking on adhesion molecule expression on monocytes and neutrophils and on circulating adhesion molecule levels in vivo

Soluble adhesion molecules have been reported as risk markers of a wide range of human diseases and specific adhesion molecules may play a direct role in pathological processes. Serum soluble intercellular adhesion molecule-1 (sICAM-1) is known to be significantly elevated in smokers compared to non-smokers. We examined the acute effects of smoking a standard 2R1 research cigarette on the serum concentration of sICAM-1 and other circulating adhesion molecules (sP-selectin, sE-selectin, sL-selectin, sVCAM-1 and sPECAM-1) in heavy smokers (serum cotinine >/= 100 ng/ml), light smokers (serum cotinine </= 60 ng/ml) and non-smokers (serum cotinine </= 10 ng/ml) by ELISA. Adhesion molecule expression on the cell surface of monocytes and neutrophils in peripheral blood was examined by flow cytometry. The sICAM-1 concentration directly correlated to serum cotinine concentration (p= 0.047) and nicotine load (p= 0.033) in smokers and was significantly elevated compared to non-smokers (p= 0.037). Other than a decrease in the concentration of sP-selectin over 1 hour regardless of smoking, no significant temporal alterations of any adhesion molecule were observed following the smoking experience or in the non-smoking control group. No significant difference in surface expression of ICAM-1, CD18, PECAM-1 or L-selectin on peripheral monocytes or neutrophils was observed over a 1-hour period following smoking. These data suggest that the elevated concentration of sICAM-1 in smokers is not due to an immediate effect of smoking.

Laser Doppler flowmeter measurement of relative gingival and forehead skin blood flow in light and heavy smokers during and after smoking

AIM

To determine the effect of the smoking experience on relative blood flow in gingiva and to compare this to skin.

METHOD

A laser Doppler flowmeter was used to record relative blood flow to healthy gingiva and to forehead skin in smokers and non-smoking controls. Smoking status was verified by quantitative analysis of serum cotinine. Continuous measurements were made over sequential periods with the subject at rest, during a sham smoking exercise, during smoking of a standard research cigarette (2R1, University of Kentucky) for 5 min and throughout a subsequent recovery period. Non-smoking controls sham smoked during the equivalent 5 minute smoking period.

RESULTS

No significant differences with respect to the proportional changes of relative gingival blood flow between time points were observed between the groups. However, between-group comparisons of relative blood flow revealed a significant increase in the relative blood flow to the forehead skin of light smokers (serum cotinine < or =60 ng/ml; n=6), when compared to heavy smokers (serum cotinine > or = 100 ng/ml; n=9) or to non-smokers (serum cotinine < or = 10 ng/ml; n=6), 2 min following the smoking experience (p = 0.007).

CONCLUSION

The results do not seem to support the theory that tobacco smoking causes localised vasoconstriction in the periodontal tissues in humans. These data show that smoking causes an acute increase in relative blood flow in forehead skin in light smokers compared to heavy smokers, suggesting a potential induction of tolerance in regular users of tobacco.

A 5-year prospective study of Astra single tooth implants

AIM

To evaluate the AstraTech Implant ST (Molndal, Sweden) for single tooth replacement clinically and radiographically after 5 years in function.

SUBJECTS AND METHOD

Fifteen patients (age range 16 to 48) with missing maxillary anterior teeth (6 central incisors, 8 laterals, 1 bicuspid) had four 13 mm and eleven 15 mm single tooth implants provided. All patients were seen at 4- to 6-monthly intervals for oral hygiene maintenance. Periapical radiographs using Rinn holders and a long cone technique were taken at the crown insertion and after 1 year, 3 and 5 years.

RESULTS

No implant losses were observed in 14 of the 15 patients available for evaluation. No abutment screw loosening or soft tissue problems were observed. At crown insertion the mean bone level was 0.46 +/- 0.55 to 0.48 +/- 0.56 mm apical to the top of the implant neck and there were no statistically significant changes in the radiographic bone level over the 5 years of the study (0.36 +/- 0.37 to 0.43 +/- 0.46 mm at year 5). One crown was recemented after 18 months in function and 1 crown was replaced because of a fracture to the porcelain incisal edge.

CONCLUSION

The Astra Tech Implants ST were highly successful in single tooth replacement and bone levels during 5 years of function were stable.

RNA turnover and protein synthesis in fish cells

Protein synthesis in fish has been previously correlated with RNA content. The present study investigates whether protein and RNA synthesis rates are similarly related. Protein and RNA synthesis rates were determined from 3H-phenylalanine and 3H-uridine incorporation, respectively, and expressed as % x day(-1) and half-lives, respectively. Three fibroblast cell lines were used: BF-2, RTP, CHSE 214, which are derived from the bluegill, rainbow trout and Chinook salmon, respectively. These cells contained similar RNA concentrations (approximately 175 microg RNA x mg(-1) cell protein). Therefore differences in protein synthesis rates, BF-2 (31.3 +/- 1.8)>RTP (25.1 +/- 1.7)>CHSE 214 (17.6 +/-1.1), were attributable to RNA translational efficiency. The most translationally efficient RNA (BF-2 cells), 1.8 mg protein synthesised x microg(-1) RNA x day(-1), corresponded to the lowest RNA half-life, 75.4 +/- 6.4 h. Translationally efficient RNA was also energetically efficient with BF-2 cells exploiting the least costly route of nucleotide supply (i.e. exogenous salvage) 3.5-6.0 times more than the least translationally efficient RNA (CHSE 214 cells). These data suggest that differential nucleotide supply, between intracellular synthesis and exogenous salvage, constitutes the area of pre-translational flexibility exploited to maintain RNA synthesis as a fixed energetic cost component of protein synthesis.

Functional status before hospitalization in acutely ill older adults: validity and clinical importance of retrospective reports

OBJECTIVES

Retrospective reports of patients' functional status before hospital admission are often used in longitudinal studies and by clinicians caring for hospitalized patients. However, the validity of these reports has not been established. Our aim was to examine the validity of retrospective reports by testing hypotheses about the relationships these measures would have with other clinical measures if they were valid.

DESIGN

A prospective cohort study.

PARTICIPANTS AND SETTING

A total of 2877 older patients (mean age 81, 36% women) hospitalized on the general medical service at two hospitals. For 1953 of the subjects, the patient was the primary respondent, whereas for 924 subjects, a surrogate was the primary respondent.

MEASUREMENTS

Shortly after hospital admission, patients or surrogates reported whether the patient was independent in each of five activities of daily living (ADLs) on admission and at baseline 2 weeks before admission. Outcome measures included reported independence in each ADL 3 months after the hospitalization and survival to 1 year.

RESULTS

Patients' retrospective reports of their ADL function 2 weeks before admission had a clinically plausible relationship with ADL function at the time of admission, in that patients independent in an ADL on admission rarely reported they were dependent in that ADL 2 weeks before admission (range 2-6%). Surrogates were somewhat more likely than patients to report that patients independent on admission were dependent 2 weeks before admission (range 5-14%). Retrospective reports of prehospitalization ADL function demonstrated strong evidence of predictive validity for both patients' and surrogates' reports. For example, among patients dependent in bathing on admission, patients who were reported as independent 2 weeks before admission were much more likely than those reported as dependent 2 weeks before admission to be independent 3 months after hospitalization (68% vs 20%, P < .001 for patient respondents; 30% vs 5%, P < .001 for surrogate respondents). Similarly, among patients dependent in bathing on hospital admission, survival 1 year after hospitalization was much higher in patients who were independent in bathing 2 weeks before admission than patients who were dependent 2 weeks before admission (76% vs 59%, P < .001 for patient respondents; 60% vs 45%, P < .001 for surrogate respondents). Results were similar for each of the other four ADLs. In a logistic regression model controlling for the number of ADLs reported as dependent on admission, the number of ADLs reported as dependent 2 weeks before admission was significantly associated with 1-year mortality among both patient (odds ratio (OR) = 1.39 per dependent ADL, 95% confidence interval (CI) - 1.26-1.54) and surrogate (OR = 1.14, 95% CI = 1.06-1.24) respondents.

CONCLUSIONS

Hospitalized patients' assessments of their ability to perform ADLs before their hospitalization have evidence of face and predictive validity. These measures are strong predictors of important health outcomes such as functioning and survival. In particular, among patients dependent in ADL function on hospital admission, these results highlight the prognostic importance of inquiring about the patient's functional status before the onset of the acute illness.

Relationship between nutritionally-mediated placental growth restriction and fetal growth, body composition and endocrine status during late gestation in adolescent sheep

The aim was to investigate the consequences of nutritionally-mediated placental growth restriction on fetal organ growth, conformation, body composition and endocrine status during late gestation. Embryos recovered from superovulated adult ewes inseminated by a single sire were transferred in singleton to the uterus of peripubertal adolescent recipients. Post-transfer, adolescent dams were offered a high (H) or moderate (M) level of a complete diet to promote rapid or moderate maternal growth rates, respectively (n=7 per group). After day 100 of gestation the feed intake of the M dams was adjusted weekly to maintain body condition score. Liveweight gain during the first 100 days of gestation was 301+/-24 and 90+/-4.6 g/day for the H and M groups, respectively. Maternal plasma concentrations of insulin, IGF-I and urea were significantly higher and non-esterified fatty acid concentrations significantly lower in H compared with M dams prior to slaughter on day 128 of gestation. At this stage of gestation, total placentome weight was 50 per cent lower in H compared with M groups (P< 0.001) and was associated with a 37 per cent reduction in fetal weight (P< 0.01). All variables of fetal conformation and absolute fetal organ weights, with the exception of the adrenal glands, were lower (P< 0. 05) in the fetuses from H intake dams. However, relative fetal organ weights expressed as g/kg fetal body weight, with the exception of the gut, were not influenced by maternal dietary intake. Furthermore, fetal weight but not maternal nutritional group were predictive of individual organ weight for all organs dissected. Together these results imply that growth restriction in the fetuses derived from H intake dams was largely symmetrical. Fetal plasma concentrations of insulin, IGF-I and glucose were attenuated (P< 0.05) in fetuses from H compared with M groups. The lower fetal body weight in the former group was associated with a reduction in absolute but not relative crude protein (P< 0.01) and fat content (P< 0.05). Total fetal liver glycogen content but not concentration was (P< 0.05) reduced in H versus M groups. The lower mass of both the placenta and fetal liver was due to a reduction in cell number rather than an alteration in cell size. Thus, over-nourishing adolescent sheep is associated with a major restriction in placental growth which mediates a gradual slowing of fetal growth during the final third of pregnancy.

Dementia DDx. Office diagnosis of the four major types of dementia

The prevalence of dementia increases with age from 1% at age 60 to about 40% at age 85. Four types of dementia--Alzheimer's disease, diffuse Lewy body dementia, frontotemporal dementia, and vascular dementia--account for 90% of all cases. The office-based physician can recognize these dementing illnesses in older patients by using existing consensus criteria. Differential diagnosis has an important bearing on patient management and prognosis, due to the potential value of treatment with some medications, possible drug toxicities in certain circumstances, and the complex care needs of patients and their families.