Effect of clinical pharmacy input on physician prescribing habits in the nursing home care unit

The goal of this study was to evaluate any changes in medication use in our 60-bed nursing home care unit as a result of eliminating clinical pharmacy services during a 2-week period. Information was obtained on patient medications and number of doses dispensed. All patients were found to have a 6% increase in average number of scheduled medications, a 3% increase in average total medications, and an increase in scheduled doses dispensed by 10% during the absence of clinical pharmacy services. These numbers declined by 16, 18, and 9%, respectively, 2 weeks after the return of clinical pharmacy services. When evaluating only those 37 patients present the entire 4 week period, average scheduled medications rose 5% and total medications rose 4% during the absence of clinical pharmacy services and declined 13 and 17%, respectively, upon return of services. Eleven patients showed an increase in total number of medications during the absence of clinical pharmacy services whereas 21 patients showed a decline in medications after the return of clinical pharmacy services (P less than 0.001). The authors conclude that clinical pharmacy services must be provided on a continuous basis to maintain good physician prescribing habits in the nursing home care unit.     

Marrow regeneration after mechanical depletion

The origin of marrow regeneration after mechanical depletion was reinvestigated in mouse chimeras. The results were compatible with the local origin of stem cells from remnants of incompletely removed marrow, but not with their origin from a common precursor of both bone and hemopoietic cell lines. In transplanted femurs depleted by a modified technique of in vivo evacuation of marrow, hemopoietic regeneration failed to occur. The presence of hemopoietic stem cells in the Haversian canals was thus excluded. The demonstration of ample hemopoiesis with minimal bone formation in nondepleted controls in which bone marrow initially became necrotic provided new evidence that osteogenesis was not a prerequisite of hemopoietic regeneration.     

Tumorigenic potential of carbaryl in the heterozygous p53 knockout mouse model.

The heterozygous p53 knockout mouse model was used to assess whether vascular tumors noted in a 2-year carcinogenicity study in CD-1 mice with carbaryl were induced through a genotoxic mechanism. This knockout mouse model was selected for carbaryl because of the high sensitivity of this model to genotoxic events and its low spontaneous incidence of tumors until 9-12 months of age. Carbaryl was administered continuously via the diet to groups of 20 male heterozygous p53 knockout mice at concentrations of 0, 10, 30, 100, 300, 1000 and 4000 ppm for 180 days. Histopathological examinations revealed no evidence of carbaryl-induced neoplasms of any type. In particular, no neoplastic or preneoplastic changes were noted in the vascular tissue of any of the organs examined. Only neoplasms, recognized as those that occur spontaneously in untreated mice of this strain, were sporadically observed in a few animals from the intermediate dose groups with no evidence of a dose- or treatment-related effect. Therefore, under the conditions of this study, the no-observed-effect level (NOEL) of carbaryl for neoplastic changes in male mice was 4000 ppm (around 716 mg/kg body weight/day). We conclude: (1) carbaryl does not appear to be a genotoxic carcinogen at least in male mice; (2) if the vascular tumors observed in the CD-1 mice are treatment-related, they could have been induced by a non-genotoxic mechanism; (3) the response in transgenic animals may provide useful complementary results to better assess carbaryl's potential genotoxic hazard to humans.     

Tamoxifen and the female genital tract

Ugwumadu AHN, Carmichael P, Neven P. Tamoxifen and the female genital tract. Int J Gynecol Cancer 1998; 8 : 6–15.
Tamoxifen was originally developed by Imperial Chemical Industries (England) (ICI) in 1966 as an anti-estrogenic contraceptive. Ironically, it found a role in the treatment of anovulatory infertility, but its most important application to date is in adjuvant hormonotherapy for breast cancer. Tamoxifen has a complex and poorly understood mix of estrogenic and anti-estrogenic properties with variable and contrasting effects on hormone-sensitive target tissues, such as the endometrium. This article reviews the gynecologic lesions associated with tamoxifen therapy and discusses the merits and acceptability of endometrial surveillance tests and the role of progestogens.     

Anatoxin-a(s), an anticholinesterase from the cyanobacterium Anabaena flos-aquae NRC-525-17

Anatoxin a(s) [antx-a(s)] given intraperitoneally to Sprague-Dawley rats at different doses (0.1-1.0 mg/kg) caused signs of severe cholinergic overstimulation. Assays of rat blood acetylcholinesterase (AChE) revealed a dose-dependent inhibition. The in vitro inhibition of electric eel acetylcholinesterase (AChE, E.C. 3.1.1.7) and horse serum butyrylcholinesterase (BUChE, E.C. 3.1.1.8) by antx-a(s) was time- and concentration-dependent. The inhibition of electric eel AChE follows first order kinetics, indicative of irreversible inhibition. The irreversibility of electric eel AChE inhibition was confirmed by a plot of Vmax versus total enzyme concentration [ET]. The kinetics of inhibition of cholinesterase by antx-a(s) supports the previous pharmacological findings that antx-a(s) is an anticholinesterase and that signs of intoxication by it are primarily due to cholinesterase inhibition.     

Human fatalities from cyanobacteria: chemical and biological evidence for cyanotoxins

An outbreak of acute liver failure occurred at a dialysis center in Caruaru, Brazil (8 degrees 17' S, 35 degrees 58' W), 134 km from Recife, the state capital of Pernambuco. At the clinic, 116 (89%) of 131 patients experienced visual disturbances, nausea, and vomiting after routine hemodialysis treatment on 13-20 February 1996. Subsequently, 100 patients developed acute liver failure, and of these 76 died. As of December 1996, 52 of the deaths could be attributed to a common syndrome now called Caruaru syndrome. Examination of phytoplankton from the dialysis clinic's water source, analyses of the clinic's water treatment system, plus serum and liver tissue of clinic patients led to the identification of two groups of cyanobacterial toxins, the hepatotoxic cyclic peptide microcystins and the hepatotoxic alkaloid cylindrospermopsin. Comparison of victims' symptoms and pathology using animal studies of these two cyanotoxins leads us to conclude that the major contributing factor to death of the dialyses patients was intravenous exposure to microcystins, specifically microcystin-YR, -LR, and -AR. From liver concentrations and exposure volumes, it was estimated that 19.5 microg/L microcystin was in the water used for dialysis treatments. This is 19.5 times the level set as a guideline for safe drinking water supplies by the World Health Organization.     

Evaluation of DISORDER: Retrospective Image Motion Correction for Volumetric Brain MRI in a Pediatric Setting

BACKGROUND AND PURPOSE:Head motion causes image degradation in brain MR imaging examinations, negatively impacting image quality, especially in pediatric populations. Here, we used a retrospective motion correction technique in children and assessed image quality improvement for 3D MR imaging acquisitions.MATERIALS AND METHODS:We prospectively acquired brain MR imaging at 3T using 3D sequences, T1-weighted MPRAGE, T2-weighted TSE, and FLAIR in 32 unsedated children, including 7 with epilepsy (age range, 2–18 years). We implemented a novel motion correction technique through a modification of k-space data acquisition: Distributed and Incoherent Sample Orders for Reconstruction Deblurring by using Encoding Redundancy (DISORDER). For each participant and technique, we obtained 3 reconstructions as acquired (Aq), after DISORDER motion correction (Di), and Di with additional outlier rejection (DiOut). We analyzed 288 images quantitatively, measuring 2 objective no-reference image quality metrics: gradient entropy (GE) and MPRAGE white matter (WM) homogeneity. As a qualitative metric, we presented blinded and randomized images to 2 expert neuroradiologists who scored them for clinical readability.RESULTS:Both image quality metrics improved after motion correction for all modalities, and improvement correlated with the amount of intrascan motion. Neuroradiologists also considered the motion corrected images as of higher quality (Wilcoxon z = −3.164 for MPRAGE; z = −2.066 for TSE; z = −2.645 for FLAIR; all P < .05).CONCLUSIONS:Retrospective image motion correction with DISORDER increased image quality both from an objective and qualitative perspective. In 75% of sessions, at least 1 sequence was improved by this approach, indicating the benefit of this technique in unsedated children for both clinical and research environments.

Head motion is a common cause of image degradation in brain MR imaging. Motion artifacts negatively impact MR image quality and therefore radiologists’ capacity to read the images, ultimately affecting patient clinical care.¹ Motion artifacts are more common in noncompliant patients,² but even in compliant adults, intrascan movement is reported in at least 10% of cases.³ For children who require high-resolution MR images, obtaining optimal image quality can be challenging, owing to the requirement to stay still over long durations needed for acquisition.⁴ Sedation can be an option, but it carries higher risks, costs, and preparation and recovery time.⁵In conditions such as intractable focal epilepsy, identification of an epileptogenic lesion is clinically important to guide surgical treatment. However, these lesions can be visually subtle, particularly in children in whom subtle cortical dysplasias are more common.⁶ Dedicated epilepsy MR imaging protocols use high-resolution 3D sequences to allow better cortical definition and free reformatting of orientation but involve acquisition times in the order of minutes, so data collection becomes more sensitive to motion.⁷For children in particular, multiple strategies are available for minimizing motion during MR examinations. Collaboration with play specialists using mock scanners and training or projecting a cartoon are good approaches to reduce anxiety.^8,9 These tools are not always available in clinical radiology and, even with these strategies, motion can still be an issue.¹⁰ Different scanning approaches to correct for intrascan motion have been proposed. Broadly, prospective methods track head motion in real time and modify the acquisition directions accordingly.¹¹ These approaches are applicable to a wide range of sequences but require optical systems with external tracking markers, sometimes uncomfortable or impractical, and extra setup can ultimately result in longer examinations. Furthermore, these approaches may also not be robust to continuous motion.^11-13 Retrospective techniques have also been proposed, in some cases relying on imaging navigators that are not compatible with all standard sequences or contrasts.¹²Here, we use a more general retrospective motion correction technique: Distributed and Incoherent Sample Orders for Reconstruction Deblurring by using Encoding Redundancy (DISORDER). In this method, k-space samples are reordered to enable retrospective motion correction during image reconstruction.¹⁴ Our hypothesis is that DISORDER improves clinical MR imaging quality and readability. To assess its use for clinical sequences, we acquired a dedicated epilepsy MR imaging protocol in 32 children across a wide age range. We used both objective image quality metrics and expert neuroradiologist ratings to evaluate the outcome after motion correction.     

First-time anterior shoulder dislocations: should they be arthroscopically stabilised?

The glenohumeral joint is inherently unstable because the large humeral head articulates with the small shadow glenoid fossa. Traumatic anterior dislocation of the shoulder is a relatively common athletic injury, and the high frequency of recurrent instability in young athletes after shoulder dislocation is discouraging to both the patient and the treating physician. Management of primary traumatic shoulder dislocation remains controversial. Traditionally, treatment involves initial immobilisation for 4–6 weeks, followed by functional rehabilitation. However, in view of the high recurrence rates associated with this traditional approach, there has been an escalating interest in determining whether immediate surgical intervention can lower the rate of recurrent shoulder dislocation, improving the patient’s quality of life. This review article aims to provide an overview of the nature and pathogenesis of first-time primary anterior shoulder dislocations, the widely accepted management modalities, and the efficacy of primary surgical intervention in first-time primary anterior shoulder dislocations.