Experimental studies on bone induction using low-molecular-weight poly (DL-lactide-co-glycolide) as a carrier for recombinant human bone morphogenetic protein-2

An appropriate carrier acting as a slow delivery vehicle for the BMPs is required for maximal clinical effectiveness of these bone-inductive proteins. The purpose of this study was to evaluate a low-molecular-weight PLGA copolymer as a synthetic, biodegradable carrier for rhBMP-2 implantation in vivo. Two, 10, or 50 microg of recombinant human BMP-2 were mixed with 10 mg of a poly (DL-lactide-co-glycolide) (PLGA) 50:50 copolymer and implanted into the calf muscles of Wistar rats. Soft X-ray analysis and histologic examination indicated that new bone formation occurred at all rhBMP-2-implanted sites within 3 weeks after implantation. Correlation of rhBMP-2 concentration with the amount of bone induction was confirmed by specific alkaline phosphatase activity and calcium content assay. In vitro analysis indicated that 78.5% of the PLGA copolymer was degraded to smaller molecular weight material after 14 days in PBS solution. It is suggested that rhBMP-2 was released in an active form at the implant site during the degradation of the copolymer, resulting in the induction of new bone formation. Thus this low-molecular-weight PLGA copolymer material represents a promising delivery vehicle for BMPs, and possibly other growth factors, around dental and orthopedic implants.     

Confidentiality and death

The duty of confidentiality in the normal doctor-patient relationship is well recognized. However, the duty of confidentiality between the pathologist who performs the autopsy and the requesting authorities and the next-of-kin is not as clearly spelt out. This article discusses the problems faced by the pathologist with regards to hospital and medico-legal autopsies in Malaysia. A proposed ethical guideline is included on how to deal with peculiar issues regarding confidentiality and the pathologist.     

An investigation of minimisation criteria

Background  

Minimisation can be used within treatment trials to ensure that prognostic factors are evenly distributed between treatment groups. The technique is relatively straightforward to apply but does require running tallies of patient recruitments to be made and some simple calculations to be performed prior to each allocation. As computing facilities have become more widely available, minimisation has become a more feasible option for many. Although the technique has increased in popularity, the mode of application is often poorly reported and the choice of input parameters not justified in any logical way.     

Thioether analogues of baclofen, phaclofen and saclofen

Analogues of baclofen, phaclofen and saclofen, incorporating a sulfur atom within the methylene chain, have been tested against responses induced by baclofen for activity at gamma-aminobutyric acid-B (GABAB) receptor sites, using a number of preparations including the guinea-pig isolated ileum and vas deferens, rat brain cortical slices and displacement of (-)-[3H]baclofen in rat cerebellar membranes. Results indicate that 2-([2-amino-1-(4-chlorophenyl)ethyl]thio)ethanephosphonic acid 2d is the most active of the new compounds. 2d is some 2-5 times weaker than phaclofen as a GABAB antagonist and approximately half as potent as phaclofen as an inhibitor of GABAB binding.     

Effects of potassium channel blockers on baclofen-induced suppression of paroxysmal discharges in rat neo-cortical slices

Baclofen reduced the frequency and aborted the bursts of spontaneous paroxysmal discharges in rat neocortical slices maintained in magnesium-free medium. This action was prevented by pretreatment with barium or caesium, which each increased the ictaform burst frequency, amplitude and duration. 4-Amino-pyridine also increased the burst frequency but reduced the amplitude and did not completely prevent the action of baclofen. Evidently baclofen suppresses such discharges by opening potassium channels normally involved in limiting the burst activity.     

Immunodetection methods for grass pollen allergens on western blots

A comparison is made of eight different methods to detect allergenic proteins in Western blots of rye-grass pollen extracts. Horseradish peroxidase-based enhanced chemiluminescence (ECL) provides a sensitive method for the detection of allergenic proteins. The method has been modified to use more dilute solutions of ECL substrate to reduce the background, can be applied to a standard nitrocellulose membrane, and used with Kodak X-ray film. The assays can be performed rapidly, replacing use of radiolabelled probes. Increased resolution is obtained. This makes the method suitable for detection of cDNA clones on plaque lifts, and for rapid and specific purification of proteins following immunodetection on nitrocellulose membranes.     

Social Media Content of Idiopathic Pulmonary Fibrosis Groups and Pages on Facebook: Cross-sectional Analysis

BackgroundPatients use Facebook as a resource for medical information. We analyzed posts on idiopathic pulmonary fibrosis (IPF)-related Facebook groups and pages for the presence of guideline content, user engagement, and usefulness.ObjectiveThe objective of this study was to describe and analyze posts from Facebook groups and pages that primarily focus on IPF-related content.MethodsCross-sectional analysis was performed on a single date, identifying Facebook groups and pages resulting from separately searching “IPF” and “idiopathic pulmonary fibrosis.” For inclusion, groups and pages needed to meet either search term and be in English, publicly available, and relevant to IPF. Every 10th post was assessed for general characteristics, source, focus, and user engagement metrics. Posts were analyzed for presence of IPF guideline content, useful scientific information (eg, scientific publications), useful support information (eg, information about support groups), and potentially harmful information.ResultsEligibility criteria were met by 12 groups and 27 pages, leading to analysis of 523 posts. Of these, 42% contained guideline content, 24% provided useful support, 20% provided useful scientific information, and 5% contained potentially harmful information. The most common post source was nonmedical users (85%). Posts most frequently focused on IPF-related news (29%). Posts containing any guideline content had fewer likes or comments and a higher likelihood of containing potentially harmful content. Posts containing useful supportive information had more likes, shares, and comments.ConclusionsFacebook contains useful information about IPF, but posts with misinformation and less guideline content have higher user engagement, making them more visible. Identifying ways to help patients with IPF discriminate between useful and harmful information on Facebook and other social media platforms is an important task for health care professionals.     

Consumer satisfaction with OTC drugs: an analysis using the confirmation/disconfirmation model

This study explored the determinants of consumer satisfaction with OTC drugs using the confirmation/disconfirmation model. A revised confirmation/disconfirmation model specifically for OTC drugs was proposed and tested using structural equation modeling with a specific product category: cold medications. The results of this study found that the confirmation/disconfirmation of a consumer's expectation and perceived performance of an OTC drug is important in predicting consumer satisfaction. Theoretical and managerial implications for pharmaceutical marketers are discussed.     

A technique for accurate use of CD4+ cell counts

Despite uncertainty over their reliability, CD4+ cell counts are used extensively in both clinical and research settings to document progression in HIV infection. We examined, therefore, whether the performance of a simple statistical test would facilitate greater accuracy in the use of this marker. CD4+ cell count data were collected from a cohort of deceased (N = 60) and living HIV-positive gay men (N = 100). Pearson's product moment correlation coefficients were calculated for each individual in order to examine the association between CD4+ counts and time since diagnosis. Correlations of 0.7 or greater were obtained in approximately 50 percent of cases in each cohort. For these individuals, CD4+ cell counts were deemed to be a reliable indicator of rate of progression. The results suggest that the proposed technique ensures greater precision in the use of CD4+ cell counts and that the technique cna be used in individuals with either complete (deceased patients) or partial (living patients) CD4+ data.