The use of QLF to quantify in vitro whitening in a product testing model. (25/449)

BACKGROUND: Professional and consumer interest in whitening products continues to increase against a background of both increased oral health awareness and demand for cosmetic procedures. In the current legal climate, few dentists are providing 'in-office' whitening treatments, and thus many patients turn to home-use products. The most common of these are the whitening toothpastes. Researchers are keen to quantify the effectiveness of such products through clinically relevant trials. AIM: Previous studies examining whitening products have employed a variety of stained substrates to monitor stain removal. This study aimed to quantify the removal of stain from human enamel using a new device, quantitative light-induced fluorescence (QLF). The experimental design follows that of a product-testing model. MATERIALS AND METHODS: A total of 11 previously extracted molar teeth were coated with transparent nail varnish leaving an exposed window of enamel. The sound, exposed enamel was subject to a staining regime of human saliva, chlorhexidine and tea. Each of the eleven teeth was subjected to serial exposures of a positive control (Bocasan), a negative control (water) and a test product (Yotuel toothpaste). Following each two-minute exposure QLF images of the teeth were taken (a total of 5 applications). Following completion of one test solution, the teeth were cleaned, re-stained and the procedure repeated with the next solution. QLF images were stored on a PC and analysed by a blinded single examiner. The deltaQ value at 5% threshold was reported. ANOVA and paired t-tests were used to analyse the data. RESULTS: The study confirmed the ability of QLF to longitudinally quantify stain reduction from human enamel. The reliability of the technique in relation to positive and negative test controls was proven. The positive control had a significantly (alpha = 0.05) higher stain removal efficacy than water (p = 0.023) and Yotuel (p = 0.046). Yotuel was more effective than water (p = 0.023). CONCLUSION: The research community, the practicing clinician and the consumer all require sound product evaluation data. The use of human enamel specimens may offer more relevant clinical data. QLF has been designed as an in vivo device. Further development of the technique should permit in vivo clinical whitening trials.  (+info)

Design and implementation of a portal for the medical equipment market: MEDICOM. (26/449)

BACKGROUND: The MEDICOM (Medical Products Electronic Commerce) Portal provides the electronic means for medical-equipment manufacturers to communicate online with their customers while supporting the Purchasing Process and Post Market Surveillance. The Portal offers a powerful Internet-based search tool for finding medical products and manufacturers. Its main advantage is the fast, reliable and up-to-date retrieval of information while eliminating all unrelated content that a general-purpose search engine would retrieve. The Universal Medical Device Nomenclature System (UMDNS) registers all products. The Portal accepts end-user requests and generates a list of results containing text descriptions of devices, UMDNS attribute values, and links to manufacturer Web pages and online catalogues for access to more-detailed information. Device short descriptions are provided by the corresponding manufacturer. The Portal offers technical support for integration of the manufacturers Web sites with itself. The network of the Portal and the connected manufacturers sites is called the MEDICOM system. OBJECTIVES: To establish an environment hosting all the interactions of consumers (health care organizations and professionals) and providers (manufacturers, distributors, and resellers of medical devices). METHODS: The Portal provides the end-user interface, implements system management, and supports database compatibility. The Portal hosts information about the whole MEDICOM system (Common Database) and summarized descriptions of medical devices (Short Description Database); the manufacturers servers present extended descriptions. The Portal provides end-user profiling and registration, an efficient product-searching mechanism, bulletin boards, links to on-line libraries and standards, on-line information for the MEDICOM system, and special messages or advertisements from manufacturers. Platform independence and interoperability characterize the system design. Relational Database Management Systems are used for the system s databases. The end-user interface is implemented using HTML, Javascript, Java applets, and XML documents. Communication between the Portal and the manufacturers servers is implemented using a CORBA interface. Remote administration of the Portal is enabled by dynamically-generated HTML interfaces based on XML documents. A representative group of users evaluated the system. The aim of the evaluation was validation of the usability of all of MEDICOM s functionality. The evaluation procedure was based on ISO/IEC 9126 Information technology - Software product evaluation - Quality characteristics and guidelines for their use. RESULTS: The overall user evaluation of the MEDICOM system was very positive. The MEDICOM system was characterized as an innovative concept that brings significant added value to medical-equipment commerce. CONCLUSIONS: The eventual benefits of the MEDICOM system are (a) establishment of a worldwide-accessible marketplace between manufacturers and health care professionals that provides up-to-date and high-quality product information in an easy and friendly way and (b) enhancement of the efficiency of marketing procedures and after-sales support.  (+info)

Sildenafil citrate: lessons learned from 3 years of clinical experience. (27/449)

In the 3 y since its initial approval, sildenafil has become the most widely used treatment for erectile dysfunction (ED) and has been prescribed to more than 13 million patients worldwide. Significant improvements in erectile function have been demonstrated in double-blind, placebo-controlled studies in diverse patient populations. A significant treatment effect has been shown with sildenafil in men with ED and a history of diabetes, cardiovascular disease, minor depression, spinal cord injury and multiple sclerosis. In addition, promising results have been shown in patients with treated prostate cancer, end-stage renal disease, Parkinson's disease and spina bifida and in multiple-organ transplant recipients. Postmarketing data of the use of sildenafil in clinical practice confirm the efficacy and safety found in clinical trials and high satisfaction with treatment. Public awareness of the common occurrence of ED and the high likelihood of a potentially favorable response to an oral treatment increased dramatically with the introduction of sildenafil. Physicians, however, are still not comfortable with ED management, which negatively affects pharmacotherapy response rates and patients' compliance to treatment. Continuing medical education seems mandatory to overcome existing problems in ED management.  (+info)

Review article: the complexity of drug development for irritable bowel syndrome. (28/449)

Drug development for functional gastrointestinal disorders is complex. These conditions involve central and peripheral physiological changes, together with psychological factors. Methodological problems have included a poor appreciation of the physiological and psychological correlates of patients' symptoms, a lack of animal models of proven relevance, and safety issues. Government, patient pressure groups and the Internet can also influence a drug's success. Most recent interest has focused on the serotonin (5-HT) modifying drugs. Cisapride has been withdrawn in some countries because of concerns related to QT prolongation and cardiac arrhythmias. The 5-HT3 antagonists, developed to modify visceral sensation, have caused constipation; alosetron, also withdrawn, caused ischaemic colitis. The 5-HT4 agonists induce peristalsis; tegaserod and prucalopride, both delayed in their development due to issues of safety and efficacy, benefit patients with 'constipation-predominant' irritable bowel syndrome or idiopathic constipation. 5-HT1 agonists improve impaired gastric accommodation and symptoms in patients with functional dyspepsia. Antidepressants also affect serotonin metabolism. Previous examples of success in this area involved drugs targeted at peripheral receptors mediating motor function or secretion. Modification of sensory function is a much more challenging objective. The experience with serotonin modifying drugs has been mixed, and some important lessons are there to be learnt.  (+info)

Changes in related drug class utilization after market withdrawal of cisapride. (29/449)

BACKGROUND: Recent Food and Drug Administration-mandated and company-initiated withdrawals of drug products from the marketplace have had an impact on utilization in related drug classes. OBJECTIVE: To investigate the impact of withdrawal of the prokinetic agent cisapride (Propulsid) on utilization of other gastrointestinal (GI) agents. STUDY DESIGN: A longitudinal, retrospective study using electronic prescription data from a state-funded geriatric prescription benefit program. PATIENTS AND METHODS: Prescription claims for 2644 patients using cisapride between January 10, 2000, and October 1, 2000, were analyzed with respect to points in time at which (1) prospective drug utilization review edits were implemented denying reimbursement of cisapride because of drug interactions, (2) the manufacturer announced its intent to cease production, and (3) the agent was withdrawn from the market. Prevalence of use, claims volume, and expenditures were compared for cisapride, proton pump inhibitors, histamine-2 receptor antagonists, and the prokinetic agent metoclopramide during these periods. RESULTS: Use of cisapride decreased precipitately even before implementation of a "medical exception only" reimbursement policy. After the change in policy, metoclopramide use increased, although this increase was not proportional to cisapride's decline. Although total GI expenditures declined within the cisapride cohort, this change had little impact on overall program GI expenditures. CONCLUSIONS: The loss of cisapride did not significantly affect program-wide costs for GI drugs. However, the withdrawal of cisapride appears to have resulted in increased use of metoclopramide, a medication with a more serious adverse effect profile than cisapride. Further study is needed to evaluate the long-term clinical impact of such therapy changes.  (+info)

Postmarket surveillance. Final rule. (30/449)

The Food and Drug Administration (FDA) is implementing the postmarket surveillance (PS) provisions of the Federal Food, Drug, and Cosmetic Act (the act), as amended by the Food and Drug Administration Modernization Act of 1997 (FDAMA). The purpose of this rule is to provide for the collection of useful data about devices that can reveal unforeseen adverse events or other information necessary to protect the public health.  (+info)

Etanercept, infliximab, and leflunomide in established rheumatoid arthritis: clinical experience using a structured follow up programme in southern Sweden. (31/449)

OBJECTIVE: To explore the feasibility of prospectively monitoring treatment efficacy and tolerability of infliximab, etanercept, and leflunomide over a two year period in patients with established rheumatoid arthritis (RA) in clinical practice using a structured protocol. METHODS: All patients with RA at seven centres in southern Sweden, for whom at least two disease modifying antirheumatic drugs, including methotrexate, had failed or not been tolerated, who started treatment with either infliximab, etanercept, or leflunomide were included. They were evaluated at predefined times using a standardised protocol including items required for evaluating response to the American College of Rheumatology (ACR) or EULAR criteria. All adverse events were recorded using World Health Organisation terminology. Concomitant treatment and survival while receiving a drug were recorded. RESULTS: During the study 166 patients were treated with etanercept, 135 with infliximab, and 103 with leflunomide. Treatment response as determined by the ACR and EULAR response criteria was similar for the tumour necrosis factor (TNF) blockers. The TNF blockers performed significantly better than leflunomide both as determined by the response criteria and by survival on drug analysis. Thus 79% and 75% continued to receive etanercept or infliximab compared with 22% of patients who started leflunomide after 20 months. The spectrum of side effects did not differ from those previously reported in the clinical trials. The initial two year experience of a protocol for postmarketing surveillance of etanercept, infliximab, and leflunomide shows that a structured protocol with central data handling can be used in clinical practice for documenting the performance of newly introduced drugs. CONCLUSIONS: Efficacy data for the TNF blockers comply with results in clinical trials, whereas leflunomide appeared to perform worse than in clinical trials. Prolonged monitoring is required to identify possible rare side effects.  (+info)

Spontaneous adverse event signaling methods: classification and use with health care treatment products. (32/449)

AE signal detection and its techniques are part of the continuum of public health surveillance, borrowing from both its theory and application (171). Like public health surveillance networks, whose major goals are to identify early signs of new outbreaks, pinpoint new organisms, and monitor designated illnesses, AE signaling and surveillance systems attempt to provide early warnings of previously unsuspected product-AE pairs, hypothesize potential drug-event relations, identify populations "at risk," and facilitate case ascertainment and definition. In both examples, definitive research is often subsequently undertaken to quantify the strength of relations that may be proposed. As with any public health surveillance effort, AE surveillance provides an infrastructure for the ongoing collection of health data and its direct integration into the health regulatory policy (172), including its keystone role in risk assessment and management. However, unlike many surveillance systems, postmarketing AE systems collect case information that is often relatively incomplete and imperfect, estimate exposure based on surrogate values (e.g., sales data), and are used by both governmental and the private sector for preventive planning. These factors make AE signaling and surveillance more ambiguous, regulatory oriented, and complex than its disease counterparts (173). Despite such issues, AE signaling methods continue to evolve in extent, complexity, and acceptance (4, 131, 174). Undoubtedly, this is largely due to the widespread practical experience that has been gained with spontaneous reporting systems over the past 4 decades and the cumulative usefulness that has been demonstrated.  (+info)