Pharmacological interventions for treating acute heterotopic ossification

BACKGROUND

Heterotopic ossification (HO) is the formation of mature lamellar bone in soft tissue sites outside the skeleton. HO frequently complicates burns, arthroplasty, fractures, and spinal cord and brain injuries. It can impair joint function.

OBJECTIVES

To determine the efficacy of medications to treat acute HO on radiological, symptomatic, functional impairment, and disability outcomes.

SEARCH STRATEGY

We searched the Cochrane Musculoskeletal Injuries Group specialised register, the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 2, 2004), MEDLINE (1966 to August 2004), EMBASE (1980 to August 2004), CINAHL (1982 to August 2004), other databases, reference lists of articles, and contacted trialists and drug companies. No language restrictions were applied.

SELECTION CRITERIA

All randomised or quasi-randomised controlled trials that assessed the efficacy of any medication for treating acute HO (confirmed by bone scintigraphy, radiography, ultrasonography, or biopsy) and which used radiography to grade post-treatment HO severity.

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed the study quality and extracted data. We analysed two dichotomous outcomes: no progression in HO grade (versus progression) and improvement in HO grade (versus no improvement).

MAIN RESULTS

Two randomised trials comparing disodium etidronate versus placebo were included (Ono 1988; Stover 1976), from which ninety-two participants with spinal cord injury had radiographically-proven HO at baseline. At the completion of the 12 week intervention, the Ono study but not the Stover study, suggested that disodium etidronate was associated with a significantly greater likelihood of successfully preventing the progression of radiographic HO grade, (relative risk (RR) 1.50; 95% confidence interval (CI) I 1.16 to 1.93; and RR 1.48; 95% CI 0.78 to 2.84 respectively) and a significantly greater likelihood of improvement in HO grade (RR 2.78; 95% CI 1.66 to 4.66; and RR 0.71; 95% CI 0.20 to 2.53 respectively). There was evidence of statistical heterogeneity for the latter outcome. Longer term radiographic, clinical or side effect outcomes were unavailable. Data was not pooled due to this heterogeneity and the inadequate duration of follow up.

REVIEWERS' CONCLUSIONS

Given the absence of long term radiographic outcomes in the included studies, there is insufficient evidence to recommend the use of disodium etidronate or other pharmacological agents for the treatment of acute HO. It has been previously suggested that disodium etidronate acts by delaying, rather than preventing, the mineralization of HO, and that mineralization may occur after treatment cessation in many cases, thereby negating the benefit of disodium etidronate on eventual HO grade. Further studies are required to assess all pharmacological treatments for acute HO with sufficient follow-up duration.

Evidence for synergistic modulation of early information processing by nicotinic and muscarinic receptors in humans

Impairments in early information processing are a hallmark feature of diverse neuropsychiatric disorders including schizophrenia and Alzheimer's disease (AD). Several lines of evidence implicate a dysfunction of the cholinergic system in these disorders, particularly in AD where there is known degeneration in major cholinergic pathways. Inspection time (IT), a measure of early visual information processing speed, has been shown to be sensitive to cholinergic manipulation. The current study employed the IT task to (1) examine the independent roles of nicotinic and muscarinic receptors in modulating information processing and (2) investigate the interaction of nicotinic and muscarinic receptor systems in modulating information processing. Twelve healthy participants completed a randomized, double-blind, placebo-controlled study under four drug conditions; (1) placebo, (2) mecamylamine (15 mg; oral), (3) scopolamine (0.4 mg, s.c.), (4) mecamylamine (15 mg) + scopolamine (0.4 mg). IT measures were examined at baseline and 2.5 h post drug administration. Selective blockade of nicotinic receptors with mecamylamine did not significantly impair IT, whereas selective blockade of muscarinic receptors with scopolamine produced a significant but small impairment in IT. Combined blockade of both receptor types with scopolamine and mecamylamine produced a large impairment in IT performance. The results indicate that both nicotinic and muscarinic receptors are involved in modulating IT, and that the two systems may function synergistically to modulate early visual information processing. These findings suggest that functional abnormalities in both nicotinic and muscarinic systems may underlie deficits in early visual information processing seen in disorders such as Alzheimer's disease and schizophrenia.

Endovascular Repair of Abdominal Aortic Aneurysm in a Patient with Renal Transplant

Patients with functioning renal transplant who develop abdominal aortic aneurysm can safely be treated with endovascular repair. Endovascular repair of aneurysm avoids renal ischemia associated with cross-clamping of aorta.

Crutch induced axillary artery injury

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Effects of Lactobacilli and an acidophilic fungus on the production performance and immune responses in broiler chickens

Accumulated lines of evidence indicate that inactivated probiotics could have beneficial effects similar to those of live probiotics. Two strains of disrupted, cobalt-enriched, lactic acid bacteria (Lactobacillus acidophilus and Lactobacillus casei) and a disrupted fungal mycelium (Scytalidium acidophilum) were spray-mixed onto a mash basal feed, in 2 concentrations, prior to pelleting. The effects of these probiotics on production performance and immune response in broiler chickens were investigated. The production parameters, including BW, feed intake (FI), BW gain (BWG), and feed conversion ratio (FCR), were monitored weekly during a 6-wk trial. The immune response was evaluated by immunizing the birds with the antigen keyhole limpet hemocyanin (KLH) followed by a serological assay to measure blood IgA and IgG titers. Some of the production parameters were significantly improved by low L. casei (LCL; for BW and BWG), high L. acidophilus (LAH; for BW and BWG), and high fungal (FH; for BW, BWG, and FI) in comparison with the nonadditive control (NC-). However, these 3 treatments (LCL, LAH, and FH) did not enhance the measured immune responses. Instead, the titers of serum KLH-specific IgA in high L. casei (LCH) and low L. acidophilus (LAL) were significantly higher than those of NC-, 10 d after immunization. None of the probiotic treatments increased the titer of KLH-specific IgG in blood. Our results indicate that disrupted and cobalt-enriched L. acidophilus or L. casei was able to enhance production performance of broiler chickens. The fungal mycelium, S. acidophilum, when used at a high concentration, also demonstrated its potential for the first time to be used as a probiotic. In addition, the optimal concentration for administering probiotics is strain dependent. A higher dose does not always result in a better performance.

Treatment of co-existing thoracic and abdominal aortic aneurysms using combined endoluminal stent grafts and conventional surgery

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Homozygous factor V Leiden mutation in a patient with traumatic leg ulceration

Factor V Leiden mutation is a well-established risk factor for venous thrombosis and ulceration. We report a 20-year-old male patient who presented with a traumatic left leg ulcer that responded poorly to therapy. He had no previous medical history. Following investigation it was discovered that the patient had extensive venous thrombosis of the left leg veins and was homozygous for the factor V Leiden gene mutation. This case demonstrates the need for detailed history taking and thorough investigation of any atypical ulcer in young adults.

Interactions of fluorochrome-labeled caspase inhibitors with apoptotic cells: a caution in data interpretation

BACKGROUND

Fluorochrome-labeled inhibitors of caspases (FLICA, e.g., FAM-VAD-FMK, FITC-VAD-FMK) have been designed as affinity labels of the enzyme active center of caspases Their binding by apoptotic cells was interpreted as reflecting activation of caspases. We have recently observed, however, that their binding is more complex and may involve additional mechanisms. Our goal in this study was to clarify the ongoing utility of these probes.

METHODS

Apoptosis of HL-60, Jurkat, MCF-7 and T-24 cells was induced by the DNA topoisomerase I inhibitor, topotecan, or by oxidative stress (H(2)O(2)). Lymphocytes were induced by their mitogenic activation. Using multiparameter laser scanning and flow cytometry analysis, the correlation between FLICA binding and the number of known apoptotic indicators was examined. These included: collapse of the mitochondrial transmembrane potential; activation of caspase-3 (detected immunocytochemically); binding of annexin V; chromatin condensation; the presence of DNA strand breaks; and loss of plasma membrane capability to exclude propidium iodide (PI). FLICA binding specificity was tested by pretreatment with z-VAD-FMK or z-DEVD-FMK.

RESULTS

FLICA binding was subsequent to the collapse of mitochondrial transmembrane potential, nearly concurrent with caspase-3 activation, and preceded annexin V binding, chromatin condensation, DNA fragmentation and loss of plasma membrane integrity. The predominant portion of FAM-VAD-FMK, FITC-VAD-FMK or FAM-DEVD-FMK binding to apoptotic cells could not be inhibited by z-VAD-FMK or z-DEVD-FMK, respectively, when the unlabeled inhibitors were added post-induction of apoptosis.

CONCLUSIONS

FLICA are specific and convenient to use markers of apoptotic cells and they detect very early events of apoptosis associated with caspases activation. Assays that combine their binding with either the loss of mitochondrial potential or with exclusion of PI as a probe of plasma membrane integrity, distinguish sequential stages of apoptosis and are particularly useful to differentiate between apoptosis and necrosis. Our results conform with the published data that unlabeled caspase inhibitors, when added after induction of apoptosis, cannot prevent activation of caspases detected by binding of biotinylated inhibitors or by cleavage of fluorogenic substrates. While FLICA binding by apoptotic cells most likely is a consequence of caspase activation, these binding events may also involve other or additional mechanisms than simply their specific attachment to the active enzyme centers of caspases.

Comparing EST-based genetic maps between Pinus sylvestris and Pinus taeda

A genetic map of Pinus sylvestris was constructed using ESTP (expressed sequence tag polymorphism) markers and other gene-based markers, AFLP markers and microsatellites. Part of the ESTP markers (40) were developed and mapped earlier in Pinus taeda, and additional markers were generated based on P. sylvestris sequences or sequences from other pine species. The mapping in P. sylvestris was based on 94 F(1) progeny from a cross between plus-tree parents E635C and E1101. AFLP framework maps for the parent trees were first constructed. The ESTP and other gene sequence-based markers were added to the framework maps, as well as five published microsatellite loci. The separate maps were then integrated with the aid of AFLPs segregating in both trees (dominant segregation ratios 3:1) as well as gene markers and microsatellites segregating in both parent trees (segregation ratios 1:1:1:1 or 1:2:1). The integrated map consisted of 12 groups corresponding to the P. taeda linkage groups, and additionally three and six smaller groups for E1101 and E635C, respectively. The number of framework AFLP markers in the integrated map is altogether 194 and the number of gene markers 61. The total length of the integrated map was 1,314 cM. The set of markers developed for P. sylvestris was also added to existing maps of two P. taeda pedigrees. Starting with a mapped marker from one pedigree in the source species resulted in a mapped marker in a pedigree of the other species in more than 40% of the cases, with about equal success in both directions. The maps of the two species are largely colinear, even if the species have diverged more than 70 MYA. Most cases of different locations were probably due to problems in identifying the orthologous members of gene families. These data provide a first ESTP-containing map of P. sylvestris, which can also be used for comparing this species to additional species mapped with the same markers.

Noninvasive technique for the repeated sampling of salivary free cortisol in awake, unrestrained squirrel monkeys

The use of noninvasive measures of hypothalamic-pituitary-adrenal (HPA) axis function is of growing interest among preclinical and clinical investigators. This report describes a method for the repeated assessment of salivary free cortisol in awake, unrestrained squirrel monkeys (Saimiri sciureus) based on a saliva sampling technique previously developed for rhesus monkeys. Individually housed adult male squirrel monkeys were trained to chew on dental rope attached to a pole, from which saliva was extracted by centrifugation and analyzed for cortisol by radioimmunoassay (RIA). Eight of nine monkeys readily acquired the task, reliably providing adequate saliva samples for the assay. Salivary free cortisol levels were examined in these subjects under basal conditions and in response to two types of neuroendocrine challenge. Levels of salivary free cortisol showed relatively low intra- and interindividual variability, with mean individual morning levels ranging between 17.1 and 37.9 microg/dl. Squirrel monkeys demonstrated a consistent daily rhythm in salivary free cortisol ranging from a high of 27.4 +/- 5.2 microg/dl (mean +/- SEM) at 12 P.M. to a low of 7.5 +/- 1.6 microg/dl at 6 P.M. Intravenous (IV) challenges with 1 microg/kg ACTH, or 10 and 50 microg/kg CRF resulted in significant increases in salivary free cortisol. The described sampling technique provides a reliable and sensitive means for repeated measurement of HPA activity in unrestrained, awake squirrel monkeys. In addition, our findings illustrate several features of HPA system rhythmicity and reactivity using salivary cortisol instead of blood plasma or serum.