Co-expression of NPY and VIP in human dental pulp

Introduction: The regulation of pulpal haemodynamics in health and disease involves sympathetic and parasympathetic mechanisms in which both neuropeptide Y (NPY; a sympathetic vasoconstrictor) and vasoactive intestinal polypeptide (VIP; a parasympathetic vasodilator) may play potential pathophysiological roles. We have previously investigated the levels of NPY or VIP present in human dental pulp tissue and shown that their expression is up-regulated in caries induced pulpal inflammation. Objectives: The aim of this study was to investigate the potential correlation between NPY and VIP levels measured in the same dental pulp samples using radioimmunoassay (RIA). Methods: Pulp tissue was obtained from extracted teeth, classified as follows; healthy (n=22), moderately carious (n=20) and grossly carious (n=26). Samples were processed for RIA by boiling in acetic acid as previously described. The levels of NPY and VIP, measured by RIA, were expressed as ng/gram of pulp tissue. The nature of the relationship between NPY and VIP levels in human pulp tissue was tested by calculating Pearson's product moment correlation coefficient using the linear regression test. Results: Calculation of Pearson product moment correlation coefficient showed a significant negative correlation between NPY and VIP levels in pulp tissue samples from non-carious teeth (p = 0.02, r = -.48). This negative correlation in non-carious teeth changed to a significant positive correlation in carious teeth when the levels of NPY and VIP were compared (p = 0.03, r= 0.311). Conclusions: In non-carious teeth, the negative correlation between NPY and VIP levels is in keeping with the previously described modulatory influence of cholinergic nerves on sympathetic function which may be perturbed as caries develops.

Vasoactive Intestinal Polypeptide (VIP) in Human Dental Pulps

Pulpal innervation is not exclusively sensory and there are potential roles for other neuropeptides such as vasoactive intestinal polypeptide (VIP) in pulpal health and disease. In the systemic circulation VIP relaxes vascular smooth muscles leading to vasodilatation. It has been shown that VIP fibres are associated with pulpal blood vessels and therefore VIP may mediate vasoactivity in the dental pulp. A growing body of evidence has now demonstrated that an additional major physiological role of VIP is to act as a survival factor. In order to gain a better understanding of the role of neuropeptides in the caries process it is of interest to specifically examine a role for VIP. Objectives: The aim of the present study was to determine the levels of VIP in carious (moderately carious and grossly carious) compared with non-carious teeth. Methods: A total of 68 teeth were included in the study (22 non-carious, 20 moderately carious and 26 grossly carious). VIP was measured in all samples using a sensitive and specific radioimmunoassay. Results: The mean concentration of VIP in the pulps of non-carious teeth was 7.69 ng/g (9.41 SD) compared to 14.93 ng/g (15.58 SD) in carious teeth. Pair-wise comparisons of VIP levels using Tukey’s test showed statistically significant differences in VIP expression between non-carious and moderately carious teeth (p=0.002) and between moderately and grossly carious teeth, (p=0.002). Conclusion: The significantly increased levels of VIP in moderately carious pulps compared with either non-carious or grossly carious pulps may suggest a role for VIP as a protective or survival factor.

Radioimmunoassay Quantitation of Neuropeptide Y (NPY) in Human Dental Pulps

Neuropeptide Y (NPY) is a 36 amino acid peptide that is abundantly expressed in both the central and peripheral nervous systems. NPY has previously been shown to be present in human dental pulp although its exact role in pulpal health and disease remains to be fully elucidated. In addition to serving a neurotransmitter role, NPY may also have a role in modulating the pulpal response to injury and inflammation. Indeed NPY is known to be a potent vasoconstrictor in a range of tissues. Recent work by our research group has demonstrated changes in sensory neuropeptide levels measured by radioimmunoassay (RIA) in healthy and carious teeth. In addition to elevated levels of sensory neuropeptides, it is also possible that the carious process is associated with increased levels of autonomic neuropeptides such as NPY. Objectives: The aim of the present study was to undertake a comprehensive quantitative RIA analysis of NPY expression in human dental pulps from carious and non-carious teeth. Methods: A total of 22 non-carious and 46 carious teeth were included in the study. NPY was measured in all samples using RIA. Briefly, the RIA system consisted of a total volume of 400 ul, comprising 100 ul anti-NPY antibody (Peninsula Laboratories), 200 ul human NPY synthetic standard or pulp sample, and 100 ul of 125I-labelled NPY as radioactive tracer. Results: The mean concentration of NPY in non-carious teeth was found to be 4.28 ng/g (4.34 SD) compared to 9.57 ng/g (9.39 SD) in carious teeth. Using ANOVA the difference in NPY levels between the non-carious group and the carious group was found to be statistically significant (p= 0.003). Conclusion: The significant increase in the levels of NPY in carious dental pulps reported in this study provides evidence for a role for NPY in the pulpal response to caries.

Neuropeptide Receptors in the Dental Pulp

Objectives: The inflammatory response to pulpal injury or infection has major clinical significance. The aim of the study is to investigate the presence and regulation of expression of neuropeptide receptors on human pulp fibroblasts and whole pulp tissue. This study will investigate the expression of Substance P (NK-1) and Neuropeptide Y (NPY-Y1) receptors on pulp fibroblasts, determine the effects of Transforming Growth Factor Beta-1 (TGF-b1) and Interleukin 1-Beta (IL-1b) on the expression of NK-1 and NPY-Y1 receptors on pulp fibroblasts and examine the levels of receptor expression in whole pulp samples. Methods: Primary pulp fibroblast cell lines were obtained from patients undergoing extractions for orthodontic reasons. The cells were grown to confluence and stimulated for 5 days with IL-1b or TGF-b1. Pulp tissue fragments were obtained from freshly extracted sound and carious teeth, snap frozen in liquid nitrogen and cracked open using a vice. The monolayer was removed with cell scrapers and pelleted. The cell membranes of the cultured cells and the whole tissue were isolated using a Mem-PER® Eukaryotic Membrane Protein Extraction Reagent Kit (Pierce, UK). The membrane proteins were separated by SDS-PAGE and Western blotting was used to detect the presence of NK-1 and NPY-Y1. Results: Initial results demonstrated the presence of NK-1 and NPY-Y1 in cultured pulp fibroblasts. Following the 5 day incubation with TGF-b1, the cells appeared not to express NK-1. IL-1b had a slight stimulatory effect on NK-1 expression. The NPY-Y1 expression was not affected by either TGF-b1 or IL-1b. In whole pulp samples, levels of NK-1 were increased in carious teeth compared to caries-free teeth. The NPY-Y1 levels were similar in carious and non-carious teeth. Conclusion: These findings give an insight into how pulp cells react to inflammatory stimuli with regards to neuropeptide receptor expression and their roles in health and disease

Comorbidity in severe asthma requiring systemic corticosteroid therapy: cross-sectional data from the Optimum Patient Care Research Database and the British Thoracic Difficult Asthma Registry

Objective: To determine the prevalence of systemic corticosteroid-induced morbidity in severe asthma.
Design: Cross-sectional observational study.Setting The primary care Optimum Patient Care Research Database and the British Thoracic Society Difficult Asthma Registry.
Participants: Optimum Patient Care Research Database (7195 subjects in three age- and gender-matched groups)—severe asthma (Global Initiative for Asthma (GINA) treatment step 5 with four or more prescriptions/year of oral corticosteroids, n=808), mild/moderate asthma (GINA treatment step 2/3, n=3975) and non-asthma controls (n=2412). 770 subjects with severe asthma from the British Thoracic Society Difficult Asthma Registry (442 receiving daily oral corticosteroids to maintain disease control).
Main outcome measures: Prevalence rates of morbidities associated with systemic steroid exposure were evaluated and reported separately for each group.
Results: 748/808 (93%) subjects with severe asthma had one or more condition linked to systemic corticosteroid exposure (mild/moderate asthma 3109/3975 (78%), non-asthma controls 1548/2412 (64%); p<0.001 for severe asthma versus non-asthma controls). Compared with mild/moderate asthma, morbidity rates for severe asthma were significantly higher for conditions associated with systemic steroid exposure (type II diabetes 10% vs 7%, OR=1.46 (95% CI 1.11 to 1.91), p<0.01; osteoporosis 16% vs 4%, OR=5.23, (95% CI 3.97 to 6.89), p<0.001; dyspeptic disorders (including gastric/duodenal ulceration) 65% vs 34%, OR=3.99, (95% CI 3.37 to 4.72), p<0.001; cataracts 9% vs 5%, OR=1.89, (95% CI 1.39 to 2.56), p<0.001). In the British Thoracic Society Difficult Asthma Registry similar prevalence rates were found, although, additionally, high rates of osteopenia (35%) and obstructive sleep apnoea (11%) were identified.

Conclusions: Oral corticosteroid-related adverse events are common in severe asthma. New treatments which reduce exposure to oral corticosteroids may reduce the prevalence of these conditions and this should be considered in cost-effectiveness analyses of these new treatments.

Sources of patient knowledge and financing of cataract surgery in rural China: the Sanrao Study of Cataract Outcomes and Up-Take of Services (SCOUTS), report 6.

AIM: To study patient sources of knowledge about cataract surgical services, and strategies for financing surgery in rural China. DESIGN: Cross-sectional case series. METHODS: Patients undergoing cataract surgery by local surgeons in a government, village-level facility in Sanrao, Guangdong between 8 August and 31 December 2005 were examined and had standardised interviews an average of 12 months after surgery. RESULTS: Of 313 eligible patients, 239 (76%) completed the questionnaire. Subjects had a mean (SD) age of 69.9 (10.2) years, 36.4% (87/239) were male, and 87.0% (208/239) had been blind (presenting visual acuity < or = 6/60) before surgery. Word-of-mouth advertising was particularly important: 198 (85.0%) of the subjects knew a person who had undergone cataract surgery, of whom 191 (96.5%) had had cataract surgery at Sanrao itself. Over 70% of subjects (166/239) watched TV daily, whereas 80.0% (188/239) "never" read the newspaper. Nearly two-thirds of suggestions from participants (n = 211, 59.6%) favoured either TV advertisements or word-of-mouth to publicise the programme. While the son or daughter had paid for surgery in over 70% of cases (164/233), the patient's having paid without help was the sole predictor of undergoing second-eye surgery (OR 2.27 (95% CI 1.01 to 5.0, p = 0.04)). DISCUSSION: Strategies to increase uptake of cataract surgery in rural China may benefit from enhancing word-of-mouth advertising (such as with pseudophakic motivators), using television advertising where affordable, and micro-credit or other programmes to enable patients to pay their own fees, thus increasing uptake of second-eye surgery.

Waiting time for cataract surgery and its influence on patient attitudes.

PURPOSE:

To characterize willingness to pay for private operations and preferred waiting time among patients awaiting cataract surgery in Hong Kong.

METHODS:

This was a cross-sectional survey. Subjects randomly selected from cataract surgical waiting lists in Hong Kong (n = 467) underwent a telephone interview based on a structured, validated questionnaire. Data were collected on private insurance coverage, preferred waiting time, amount willing to pay for surgery, and self-reported visual function and health status.

RESULTS:

Among 300 subjects completing the interview, 144 (48.2%) were 76 years of age or older, 177 (59%) were women, and mean time waiting for surgery was 17 +/- 15 months. Among 220 subjects (73.3%) willing to pay anything for surgery, the mean amount was US$552 +/- 443. With adjustment for age, education, and monthly household income, subjects willing to pay anything were less willing to wait 12 months for surgery (OR = 4.34; P = 0.002), more likely to know someone having had cataract surgery (OR = 2.20; P = 0.03), and more likely to use their own savings to pay for the surgery (OR = 2.21; P = 0.04). Subjects considering private cataract surgery, knowing people who have had cataract surgery, using nongovernment sources to pay for surgery, and having lower visual function were willing to pay more.

CONCLUSIONS:

Many patients wait significant periods for cataract surgery in Hong Kong, and are willing to pay substantial amounts for private operations. These results may have implications for other countries with cataract waiting lists.

Tooth replacement for partially dentate elders: a willingness-to-pay analysis

Objectives: The primary aim of this study was to investigate partially dentate elders’ willingness-to-pay (WTP) for two different tooth replacement strategies: using Removable Partial Dentures (RPDs) and, functionally orientated treatment (SDA). The secondary aim was to measure the same patient group’s WTP for dental implants.Methods: Patients who had completed a previous RCT comparing two tooth replacement strategies (RPDs and SDA) were recruited. 59 patients were asked to indicate their WTP for treatment to replace missing teeth in a number of hypothetical scenarios using the payment card method of contingency evaluation coupled to different costs. Data were collected on patients’ social class, longest held occupation, income levels and social circumstances.Results: The median age for the patient sample was 72.0 years (IQR: 71-75 years). Patients who had previously been provided with RPDs indicated that their WTP for this treatment strategy was significantly higher than those patients who had received SDA treatment (Mann-Whitney U Test: p<0.001). This group were also WTP a higher price for SDA treatment than those patients who had previously been treated according to this modality (Mann-Whitney U Test: p=0.005). The results indicated that patients’ age was not correlated with WTP but both social class and current income levels were significantly correlated (Spearman’s rank correlation: p<0.05).Patients in both treatment groups exhibited llittle WTP for dental implant treatment with a median price recorded which was lower than either RPD or SDA treatment.Conclusions: Amongst this patient cohort previous treatment experience had a strong influence on WTP as did social class and current income levels. The patients’ WTP indicated that they did not value dental implants over simpler forms of tooth replacement such as RPDs or a SDA approach.

The prevalence of caries in patients referred for orthodontic assessment in Northern Ireland – A retrospective study

Objectives: To determine the prevalence of untreated carious lesions in permanent teeth in patients (under the age of 18) referred for an orthodontic assessment in specialist practice. In addition, the figures shall be compared with national data for Northern Ireland (as outlined in the recent Child Dental Health Survey 2013)
The Gold standard would be that 100% of patients would be caries free upon presentation.

Methods: The clinical records and radiographs (OPT of quality grading 1 or 2) of 337 patients were reviewed. This encompassed patients who had an orthodontic assessment carried out in specialist practice over a 6 month period (following referral from their general dental practitioner)

Results: A total of 337 patient records were examined. Of these, 149 were male (44.2%) and 188 were female (55.8%), with an age range of 7-17 years at the time of new patient assessment. It was found that 36 patients (10.7%) had evidence (clinical and/or radiographic) of active and untreated dental caries. Of those affected, 14 were male and 22 were female.
Breaking the data down in terms of age, we can also get some indication as to how this cohort compares with national data for Northern Ireland :⃰

7-10 years (Mean = 9.3) = 14.3% caries (versus NI average of 6% for 8 year olds)
11-13 years (Mean = 12.1) = 10.1% caries, (versus NI average of 16% for 12 year olds)
14-17 years (Mean = 15.2) = 9.1% caries (versus NI average of 15% for 15 year olds)

⃰using the diagnostic threshold “Decay into dentine (visual dentine caries excluded)”


Conclusion: In this sample group, a total of 10.7% of patients (9.4% of males, 11.7% of females) presented with evidence of undiagnosed caries upon being assessed as a new patient in specialist orthodontic practice. Hence, the gold standard was not met.