Kinetics of metabolism of deltamethrin and cis- and trans-permethrin in vitro. Studies using rat and human liver microsomes, isolated rat hepatocytes and rat liver cytosol.

The kinetics of metabolism of deltamethrin (DLM) and cis- and trans-permethrin (CPM and TPM) was studied in male Sprague-Dawley rat and human liver microsomes. DLM metabolism kinetics was also studied in isolated rat hepatocytes, liver microsomes and cytosol. Apparent intrinsic clearance (CLint) values for the metabolism of DLM, CPM and TPM by cytochrome P450 (CYP) and carboxylesterase (CES) enzymes in rat and human liver microsomes decreased with increasing microsomal protein concentration. However, when apparent CLint values were corrected for nonspecific binding to allow calculation of unbound (i.e., corrected) CLint values, the unbound values did not vary greatly with microsomal protein concentration. Unbound CLint values for metabolism of 0.05-1 µM DLM in rat liver microsomes (CYP and CES enzymes) and cytosol (CES enzymes) were not significantly different from rates of DLM metabolism in isolated rat hepatocytes. This study demonstrates that the nonspecific binding of these highly lipophilic compounds needs to be taken into account in order to obtain accurate estimates of rates of in vitro metabolism of these pyrethroids. While DLM is rapidly metabolised in vitro, the hepatocyte membrane does not appear to represent a barrier to the absorption and hence subsequent hepatic metabolism of this pyrethroid.

An assay for screening xenobiotics for inhibition of rat thyroid gland peroxidase activity.

1. A number of chemicals have been shown to produce disruption of the thyroid gland, resulting in reduced thyroid hormone synthesis, by a mechanism involving inhibition of thyroid peroxidase (TPO) activity (EC 1.11.1.8).2. An assay was developed for rat thyroid gland microsomal TPO activity, employing L-tyrosine as the physiological substrate, with analysis of the formation of the 3-iodo-L-tyrosine (3MIT) metabolite by ultra-performance liquid chromatography-mass spectrometry-mass spectrometry.3. Formation of 3MIT was linear with respect to both rat thyroid gland microsomal protein concentration and incubation time, whereas only small quantities of 3,5-diodo-L-tyrosine were formed.4. Studies were performed with nine known TPO inhibitors. The most potent inhibitors were 3-amino-1,2,4-triazole, ethylene thiourea, methimazole and 6-propyl-2-thiouracil which had IC50 values (i.e. concentration to produce a 50% inhibition of enzyme activity) of 0.059, 0.791, 1.07 and 1.96 µM, respectively, whereas the least potent inhibitor was sodium perchlorate which had an IC50 value of 13,800 µM.5. For five inhibitors, where literature data were available, the observed IC50 values obtained in this study employing rat thyroid gland microsomes and L-tyrosine as substrate were similar to those previously reported using the spectrophotometric guaiacol oxidation assay.

Change in Low Back Movement Patterns After Neurosurgical Intervention for Lumbar Spondylosis.

OBJECTIVES: The purpose of this study was to assess the use of computer-aided combined movement examination (CME) to measure change in low back movement after neurosurgical intervention for lumbar spondylosis and to use a CME normal reference range (NRR) to compare and contrast movement patterns identified from lumbar disk disease, disk protrusion, and nerve root compression cases. METHODS: A test-retest, cohort observational study was conducted. Computer-aided CME was used to record lumbar range of motion in 18 patients, along with pain, stiffness, disability, and health self-report questionnaires. A minimal clinically important difference of 30% was used to interpret meaningful change in self-reports. z Scores were used to compare CME. Post hoc observation included subgrouping cases into 3 discrete pathologic conditions-disk disease, disk protrusion, and nerve root compression-to report intergroup differences in CME. RESULTS: Self-report data indicated that 11, 7, and 10 patients improved by ≥30% in pain, stiffness, and function, respectively. Three patients experienced clinically significant improvement in health survey. A CME pattern reduced in all directions suggested disk disease. Unilaterally restricted movement in side-flexed or extended directions suggested posterolateral disk protrusion with or without ipsilateral nerve root compression. Bilateral restrictions in extension suggested posterior disk protrusion with or without nerve root compression. In 11 of the 18 cases, CME converged toward the NRR after surgery. CONCLUSION: We described the use of CME to identify atypical lumbar movement relative to an NRR. Data from this short-term postoperative study provide preliminary evidence for CME movement patterns suggestive of disk disease, disk protrusion, and nerve root compression.

Structure-Specific Movement Patterns in Patients With Chronic Low Back Dysfunction Using Lumbar Combined Movement Examination.

OBJECTIVE: A test-retest cohort study was conducted to assess the use of a novel computer-aided, combined movement examination (CME) to measure change in low back movement after pain management intervention in 17 cases of lumbar spondylosis. Additionally we desired to use a CME normal reference range (NRR) to compare and contrast movement patterns identified from 3 specific structural pathologic conditions: intervertebral disc, facet joint, and nerve root compression. METHODS: Computer-aided CME was used before and after intervention, in a cohort study design, to record lumbar range of movement along with pain, disability, and health self-report questionnaires in 17 participants who received image-guided facet, epidural, and/or rhizotomy intervention. In the majority of cases, CME was reassessed after injection together with 2 serial self-reports after an average of 2 and 14 weeks. A minimal clinically important difference of 30% was used to interpret meaningful change in self-reports. A CME NRR (n = 159) was used for comparison with the 17 cases. Post hoc observation included subgrouping cases into 3 discrete pathologic conditions, intervertebral disc, facet dysfunction, and nerve root compression, in order to report intergroup differences in CME movement. RESULTS: Seven of the 17 participants stated that a "combined" movement was their most painful CME direction. Self-report outcome data indicated that 4 participants experienced significant improvement in health survey, 5 improved by ≥30% on low back function, and 8 reported that low back pain was more bothersome than stiffness, 6 of whom achieved the minimal clinically important difference for self-reported pain. Subgrouping of cases into structure-specific groups provided insight to different CME movement patterns. CONCLUSION: The use of CME assists in identifying atypical lumbar movement relative to an age and sex NRR. Data from this study, exemplified by representative case studies, provide preliminary evidence for distinct intervertebral disc, facet joint, and nerve root compression CME movement patterns in cases of chronic lumbar spondylosis.

Murine model of chemotherapy-induced extraintestinal pathogenic Escherichia coli translocation.

Escherichia coli is a major cause of life-threatening infections in patients with neutropenia, particularly those receiving chemotherapy for the treatment of cancer. In most cases, these infections originate from opportunistic strains living within the patient's gastrointestinal tract which then translocate to major organ systems. There are no animal models that faithfully recapitulate these infections, and, as such, the host or bacterial factors that govern this process remain unidentified. We present here a novel model of chemotherapy-induced bacterial translocation of E. coli. Oral gavage of BALB/c mice with a clinical isolate of extraintestinal pathogenic E. coli (ExPEC) leads to stable and long-term colonization of the murine intestine. Following the induction of neutropenia with the chemotherapeutic drug cyclophosphamide, ExPEC translocates from the intestine to the lungs, liver, spleen, and kidneys with concomitant morbidity in infected animals. Translocation can also occur in mice bearing mammary tumors, even in the absence of chemotherapy. Translocation of ExPEC is also associated with an increase of the diversity of bacterial DNA detected in the blood. This is the first report of a chemotherapy-based animal model of ExPEC translocation in cancerous mice, a system that can be readily used to identify important virulence factors for this process.

Resistin deficiency in mice has no effect on pulmonary responses induced by acute ozone exposure.

Acute exposure to ozone (O3), an air pollutant, causes pulmonary inflammation, airway epithelial desquamation, and airway hyperresponsiveness (AHR). Pro-inflammatory cytokines-including IL-6 and ligands of chemokine (C-X-C motif) receptor 2 [keratinocyte chemoattractant (KC) and macrophage inflammatory protein (MIP)-2], TNF receptor 1 and 2 (TNF), and type I IL-1 receptor (IL-1α and IL-1ß)-promote these sequelae. Human resistin, a pleiotropic hormone and cytokine, induces expression of IL-1α, IL-1ß, IL-6, IL-8 (the human ortholog of murine KC and MIP-2), and TNF. Functional differences exist between human and murine resistin; yet given the aforementioned observations, we hypothesized that murine resistin promotes O3-induced lung pathology by inducing expression of the same inflammatory cytokines as human resistin. Consequently, we examined indexes of O3-induced lung pathology in wild-type and resistin-deficient mice following acute exposure to either filtered room air or O3. In wild-type mice, O3 increased bronchoalveolar lavage fluid (BALF) resistin. Furthermore, O3 increased lung tissue or BALF IL-1α, IL-6, KC, TNF, macrophages, neutrophils, and epithelial cells in wild-type and resistin-deficient mice. With the exception of KC, which was significantly greater in resistin-deficient compared with wild-type mice, no genotype-related differences in the other indexes existed following O3 exposure. O3 caused AHR to acetyl-ß-methylcholine chloride (methacholine) in wild-type and resistin-deficient mice. However, genotype-related differences in airway responsiveness to methacholine were nonexistent subsequent to O3 exposure. Taken together, these data demonstrate that murine resistin is increased in the lungs of wild-type mice following acute O3 exposure but does not promote O3-induced lung pathology.

Neurovirulence and immunogenicity of attenuated recombinant vesicular stomatitis viruses in nonhuman primates.

UNLABELLED: In previous work, a prototypic recombinant vesicular stomatitis virus Indiana serotype (rVSIV) vector expressing simian immunodeficiency virus (SIV) gag and human immunodeficiency virus type 1 (HIV-1) env antigens protected nonhuman primates (NHPs) from disease following challenge with an HIV-1/SIV recombinant (SHIV). However, when tested in a stringent NHP neurovirulence (NV) model, this vector was not adequately attenuated for clinical evaluation. For the work described here, the prototypic rVSIV vector was attenuated by combining specific G protein truncations with either N gene translocations or mutations (M33A and M51A) that ablate expression of subgenic M polypeptides, by incorporation of temperature-sensitive mutations in the N and L genes, and by deletion of the VSIV G gene to generate a replicon that is dependent on trans expression of G protein for in vitro propagation. When evaluated in a series of NHP NV studies, these attenuated rVSIV variants caused no clinical disease and demonstrated a very significant reduction in neuropathology compared to wild-type VSIV and the prototypic rVSIV vaccine vector. In spite of greatly increased in vivo attenuation, some of the rVSIV vectors elicited cell-mediated immune responses that were similar in magnitude to those induced by the much more virulent prototypic vector. These data demonstrate novel approaches to the rational attenuation of VSIV NV while retaining vector immunogenicity and have led to identification of an rVSIV N4CT1gag1 vaccine vector that has now successfully completed phase I clinical evaluation. IMPORTANCE: The work described in this article demonstrates a rational approach to the attenuation of vesicular stomatitis virus neurovirulence. The major attenuation strategy described here will be most likely applicable to other members of the Rhabdoviridae and possibly other families of nonsegmented negative-strand RNA viruses. These studies have also enabled the identification of an attenuated, replication-competent rVSIV vector that has successfully undergone its first clinical evaluation in humans. Therefore, these studies represent a major milestone in the development of attenuated rVSIV, and likely other vesiculoviruses, as a new vaccine platform(s) for use in humans.

Effect of antigen sensitization and challenge on oscillatory mechanics of the lung and pulmonary inflammation in obese carboxypeptidase E-deficient mice.

Atopic, obese asthmatics exhibit airway obstruction with variable degrees of eosinophilic airway inflammation. We previously reported that mice obese as a result of a genetic deficiency in either leptin (ob/ob mice) or the long isoform of the leptin receptor (db/db mice) exhibit enhanced airway obstruction in the presence of decreased numbers of bronchoalveolar lavage fluid (BALF) eosinophils compared with lean, wild-type mice following antigen (ovalbumin; OVA) sensitization and challenge. To determine whether the genetic modality of obesity induction influences the development of OVA-induced airway obstruction and OVA-induced pulmonary inflammation, we examined indices of these sequelae in mice obese as a result of a genetic deficiency in carboxypeptidase E, an enzyme that processes prohormones and proneuropeptides involved in satiety and energy expenditure (Cpe(fat) mice). Accordingly, Cpe(fat) and lean, wild-type (C57BL/6) mice were sensitized to OVA and then challenged with either aerosolized PBS or OVA. Compared with genotype-matched, OVA-sensitized and PBS-challenged mice, OVA sensitization and challenge elicited airway obstruction and increased BALF eosinophils, macrophages, neutrophils, IL-4, IL-13, IL-18, and chemerin. However, OVA challenge enhanced airway obstruction and pulmonary inflammation in Cpe(fat) compared with wild-type mice. These results demonstrate that OVA sensitization and challenge enhance airway obstruction in obese mice regardless of the genetic basis of obesity, whereas the degree of OVA-induced pulmonary inflammation is dependent on the genetic modality of obesity induction. These results have important implications for animal models of asthma, as modeling the pulmonary phenotypes for subpopulations of atopic, obese asthmatics critically depends on selecting the appropriate mouse model.

Predicting Alzheimer disease with ß-amyloid imaging: results from the Australian imaging, biomarkers, and lifestyle study of ageing.

OBJECTIVE: Biomarkers for Alzheimer disease (AD) can detect the disease pathology in asymptomatic subjects and individuals with mild cognitive impairment (MCI), but their cognitive prognosis remains uncertain. We aimed to determine the prognostic value of ß-amyloid imaging, alone and in combination with memory performance, hippocampal atrophy, and apolipoprotein E ε4 status in nondemented, older individuals. METHODS: A total of 183 healthy individuals (age = 72.0 ± 7.26 years) and 87 participants with MCI (age = 73.7 ± 8.27) in the Australian Imaging, Biomarkers, and Lifestyle study of ageing were studied. Clinical reclassification was performed after 3 years, blind to biomarker findings. ß-Amyloid imaging was considered positive if the (11) C-Pittsburgh compound B cortical to reference ratio was ≥1.5. RESULTS: Thirteen percent of healthy persons progressed (15 to MCI, 8 to dementia), and 59% of the MCI cohort progressed to probable AD. Multivariate analysis showed ß-amyloid imaging as the single variable most strongly associated with progression. Of combinations, subtle memory impairment (Z score = -0.5 to -1.5) with a positive amyloid scan was most strongly associated with progression in healthy individuals (odds ratio [OR] = 16, 95% confidence interval [CI] = 3.7-68; positive predictive value [PPV] = 50%, 95% CI = 19-81; negative predictive value [NPV] = 94%, 95% CI = 88-98). Almost all amnestic MCI subjects (Z score ≤ -1.5) with a positive amyloid scan developed AD (OR = ∞; PPV = 86%, 95% CI = 72-95; NPV = 100%, 95% CI = 80-100). Hippocampal atrophy and ε4 status did not add further predictive value. INTERPRETATION: Subtle memory impairment with a positive ß-amyloid scan identifies healthy individuals at high risk for MCI or AD. Clearly amnestic patients with a positive amyloid scan have prodromal AD and a poor prognosis for dementia within 3 years.

Effects of the assessment of 4 determinants of structural geometry on QCT- and DXA-derived hip structural analysis measurements in elderly women.

Previously we reported that the corresponding 2-dimensional (2D) structural geometry measures derived from quantitative computed tomography (QCT) and dual-energy X-ray absorptiometry (DXA) of femoral neck were different. Now, we test the hypothesis that the following 4 measures: areal bone mineral density, W, and 2 new measures, standard deviation (σ) of a normalized mineral mass projection profile distribution and the displacement between centre of mineral mass and geometric centre of mineral mass (δ) of the projection profile allow transformation from one measurement modality to the other with high precision. QCT and DXA scans and hip structural analysis (HSA) performed on 237 women were randomly allocated into cohorts of 118 (cohort A) and 119 (cohort B). Intercepts and gradients from linear regression of the 4 QCT- and DXA-derived measures were obtained from cohort A and used to convert cohort B QCT-derived structural geometry measurements into their DXA equivalent. Corresponding cohort B QCT- and DXA-derived structural geometrical measurements were compared using Bland-Altman plots and regression analysis. Apart from W, comparisons of the 7 nontransformed QCT- and DXA-derived variables were significantly different using paired t-tests. Cross-calibration with the set of 4 base measures resolved the differences in all original variables. These data provide a mechanism for cross-calibrating HSA outcomes acquired using QCT and DXA and demonstrate that a complex 2D digitized structure can be described by 4 variables.

Development of competency models for assessors and simulators in high-stakes selection processes.

BACKGROUND: Selection for entry into UK medical specialty training is a high-stakes, high-volume process. For selection into General Practice, a large number of assessors and simulators are involved in the delivery of the selection centre, which represents the final stage of selection. AIM: In order to standardize and quality-assure assessor and simulator involvement in the process, we developed two competency models outlining the knowledge, skills and attributes associated with each role using a previously validated job analysis methodology. RESULTS: The final qualitative analysis resulted in two competency models, each encompassing eight competency domains. In general, results from a validation questionnaire demonstrated positive feedback from various regional recruitment leads in the UK (n = 14). CONCLUSION: Both models are currently being used in practice for quality assurance and training purposes. We conclude that the competency models can be used in three ways: (1) recruiting assessors/simulators; (2) in measuring performance of assessors/simulators and highlighting areas for potential development; and (3) they can be used for training assessors/simulators.

Enzyme-mediated site-specific bioconjugation of metal complexes to proteins: sortase-mediated coupling of copper-64 to a single-chain antibody.

The enzyme-mediated site-specific bioconjugation of a radioactive metal complex to a single-chain antibody using the transpeptidase sortase A is reported. Cage amine sarcophagine ligands that were designed to function as substrates for the sortase A mediated bioconjugation to antibodies were synthesized and enzymatically conjugated to a single-chain variable fragment. The antibody fragment scFv(anti-LIBS) targets ligand-induced binding sites (LIBS) on the glycoprotein receptor GPIIb/IIIa, which is present on activated platelets. The immunoconjugates were radiolabeled with the positron-emitting isotope (64)Cu. The new radiolabeled conjugates were shown to bind selectively to activated platelets. The diagnostic potential of the most promising conjugate was demonstrated in an in vivo model of carotid artery thrombosis using positron emission tomography. This approach gives homogeneous products through site-specific enzyme-mediated conjugation and should be broadly applicable to other metal complexes and proteins.

Diagnostic imaging agents for Alzheimer's disease: copper radiopharmaceuticals that target Aß plaques.

One of the pathological hallmarks of Alzheimer's disease is the presence of amyloid-ß plaques in the brain and the major constituent of these plaques is aggregated amyloid-ß peptide. New thiosemicarbazone-pyridylhydrazine based ligands that incorporate functional groups designed to bind amyloid-ß plaques have been synthesized. The new ligands form stable four coordinate complexes with a positron-emitting radioactive isotope of copper, (64)Cu. Two of the new Cu(II) complexes include a functionalized styrylpyridine group and these complexes bind to amyloid-ß plaques in samples of post-mortem human brain tissue. Strategies to increase brain uptake by functional group manipulation have led to a (64)Cu complex that effectively crosses the blood-brain barrier in wild-type mice. The new complexes described in this manuscript provide insight into strategies to deliver metal complexes to amyloid-ß plaques.

Endogenous osteopontin promotes ozone-induced neutrophil recruitment to the lungs and airway hyperresponsiveness to methacholine.

Inhalation of ozone (O3), a common environmental pollutant, causes pulmonary injury, pulmonary inflammation, and airway hyperresponsiveness (AHR) in healthy individuals and exacerbates many of these same sequelae in individuals with preexisting lung disease. However, the mechanisms underlying these phenomena are poorly understood. Consequently, we sought to determine the contribution of osteopontin (OPN), a hormone and a pleiotropic cytokine, to the development of O3-induced pulmonary injury, pulmonary inflammation, and AHR. To that end, we examined indices of these aforementioned sequelae in mice genetically deficient in OPN and in wild-type, C57BL/6 mice 24 h following the cessation of an acute (3 h) exposure to filtered room air (air) or O3 (2 parts/million). In wild-type mice, O3 exposure increased bronchoalveolar lavage fluid (BALF) OPN, whereas immunohistochemical analysis demonstrated that there were no differences in the number of OPN-positive alveolar macrophages between air- and O3-exposed wild-type mice. O3 exposure also increased BALF epithelial cells, protein, and neutrophils in wild-type and OPN-deficient mice compared with genotype-matched, air-exposed controls. However, following O3 exposure, BALF neutrophils were significantly reduced in OPN-deficient compared with wild-type mice. When airway responsiveness to inhaled acetyl-ß-methylcholine chloride (methacholine) was assessed using the forced oscillation technique, O3 exposure caused hyperresponsiveness to methacholine in the airways and lung parenchyma of wild-type mice, but not OPN-deficient mice. These results demonstrate that OPN is increased in the air spaces following acute exposure to O3 and functionally contributes to the development of O3-induced pulmonary inflammation and airway and lung parenchymal hyperresponsiveness to methacholine.

Evaluation of the metabolism and hepatotoxicity of xenobiotics utilizing precision-cut slices.

1. Precision-cut liver slices are a valuable in vitro model system to study the metabolism and toxicity of xenobiotics. Liver slices retain tissue architecture so that all cell types are present and intercellular communication between the various cell types is retained. 2. Precision-cut liver slices from humans and other species have been used to study pathways of phase I (e.g. cytochrome P450-dependent biotransformations) and II (e.g. conjugation with D-glucuronic acid, sulphate and glutathione) metabolism of a wide range of xenobiotics. 3. Liver slices can also be employed to investigate the induction and inhibition of xenobiotic metabolizing enzymes and to obtain kinetic data on the rates of metabolism of xenobiotics. 4. Precision-cut liver slices from humans and other species have been used to study the toxicity of a wide variety of xenobiotics. Toxicity can be assessed by various techniques including gene expression, morphological examination and a wide range of biochemical endpoints. 5. Precision-cut liver slices can be utilized to examine species differences in hepatic xenobiotic metabolism and xenobiotic-induced toxicity, thus permitting comparisons between animal species and humans.

An integration of genome-wide association study and gene expression profiling to prioritize the discovery of novel susceptibility Loci for osteoporosis-related traits.

Osteoporosis is a complex disorder and commonly leads to fractures in elderly persons. Genome-wide association studies (GWAS) have become an unbiased approach to identify variations in the genome that potentially affect health. However, the genetic variants identified so far only explain a small proportion of the heritability for complex traits. Due to the modest genetic effect size and inadequate power, true association signals may not be revealed based on a stringent genome-wide significance threshold. Here, we take advantage of SNP and transcript arrays and integrate GWAS and expression signature profiling relevant to the skeletal system in cellular and animal models to prioritize the discovery of novel candidate genes for osteoporosis-related traits, including bone mineral density (BMD) at the lumbar spine (LS) and femoral neck (FN), as well as geometric indices of the hip (femoral neck-shaft angle, NSA; femoral neck length, NL; and narrow-neck width, NW). A two-stage meta-analysis of GWAS from 7,633 Caucasian women and 3,657 men, revealed three novel loci associated with osteoporosis-related traits, including chromosome 1p13.2 (RAP1A, p = 3.6x10(-8)), 2q11.2 (TBC1D8), and 18q11.2 (OSBPL1A), and confirmed a previously reported region near TNFRSF11B/OPG gene. We also prioritized 16 suggestive genome-wide significant candidate genes based on their potential involvement in skeletal metabolism. Among them, 3 candidate genes were associated with BMD in women. Notably, 2 out of these 3 genes (GPR177, p = 2.6x10(-13); SOX6, p = 6.4x10(-10)) associated with BMD in women have been successfully replicated in a large-scale meta-analysis of BMD, but none of the non-prioritized candidates (associated with BMD) did. Our results support the concept of our prioritization strategy. In the absence of direct biological support for identified genes, we highlighted the efficiency of subsequent functional characterization using publicly available expression profiling relevant to the skeletal system in cellular or whole animal models to prioritize candidate genes for further functional validation.

What causes adverse events in prehospital care? A human-factors approach.

BACKGROUND: The last decade has seen a vast amount of work directed at the investigation of patient harm events. Unfortunately, little of it has pertained to prehospital care and as such, risk remains unquantified and poorly understood in this setting. We hypothesised that adverse patient events occurring during the prehospital phase may fall into discernible patterns, and that an understanding of these patterns would be valuable in the development of mitigation strategies. METHODS: A survey tool was developed with reference to the human factors literature. Paramedics in a large Australian ambulance service were asked to recall an adverse event and to nominate factors that may have contributed to its occurrence. Responses were analysed using principal components analysis in order to identify contributory factors that could be statistically grouped together in meaningful patterns. RESULTS: The survey yielded 370 responses. Eight key single contributors and 14 groups of contributory factors were identified. Of the groups, only two were strongly associated with serious patient outcomes, such as reported significant deterioration or death. CONCLUSIONS: The deteriorating patient was identified as the leading single contributor to prehospital adverse events, and two perfect storm patient harm scenarios were found to contribute materially to adverse outcomes. This approach to identifying both single factors contributing to an incident and factors which could be grouped together in a pattern, appears useful in delineating risk in the acute prehospital setting, and warrants further exploration in this and other areas of patient safety.

Invasions and Local Outbreaks of Four Species of Plague Locusts in South Africa: A Historical Review of Outbreak Dynamics and Patterns.

The current paper provides a detailed review of the historical outbreaks of each of the four plague locust species found in South Africa, namely the brown locust, the African migratory locust, the red locust, and the southern African desert locust. The history and dynamics of the plague infestations and the major local outbreaks are summarized. The typical patterns of the outbreaks of the different species are described, and the threat of these locusts to agriculture in South Africa is defined. The brown locust produces regular outbreaks in the semi-arid Karoo, with large-scale eruptions of plague proportions occurring about once per decade. Patterns of outbreaks often repeat themselves, but the sheer size of the plague outbreaks is almost impossible to stop, and the brown locust has the potential to threaten food security throughout southern Africa. The African migratory locust produces outbreaks in some of the main maize and wheat cropping areas where it is difficult to control. This locust has taken advantage of the man-made crop environment to produce an extra generation per year that was not previously possible in the original grasslands. The coastal area of KwaZulu Natal Province in South Africa was a prime reception and breeding area for plague invasions of the red locust in the past, and the country, therefore, relies on the successful control of outbreaks in east and central Africa to prevent the recurrence of the plague invasions. The southern African desert locust occurs in the Kalahari Desert area, and outbreaks requiring chemical control are rare.

Heart-specific overexpression of CUGBP1 reproduces functional and molecular abnormalities of myotonic dystrophy type 1.

Myotonic dystrophy type 1 (DM1) is caused by a CTG expansion within the 3'-untranslated region of the DMPK gene. The predominant mechanism of pathogenesis is a toxic gain of function of CUG repeat containing RNA transcribed from the expanded allele. The molecular mechanisms by which the RNA containing expanded repeats produce pathogenic effects include: sequestration of muscleblind-like 1 (MBNL1) protein and up-regulation of CUG binding protein 1 (CUGBP1). MBNL1 and CUGBP1 are RNA binding proteins that regulate alternative splicing transitions during development. Altered functions of these proteins in DM1 lead to misregulated splicing of their target genes, resulting in several features of the disease. The role of MBNL1 depletion in DM1 is well established through a mouse knock-out model that reproduces many disease features. Here we directly test the hypothesis that CUGBP1 up-regulation also contributes to manifestations of DM1. Using tetracycline-inducible CUGBP1 and heart-specific reverse tetracycline trans-activator transgenes, we expressed human CUGBP1 in adult mouse heart. Our results demonstrate that up-regulation of CUGBP1 is sufficient to reproduce molecular, histopathological and functional changes observed in a previously described DM1 mouse model that expresses expanded CUG RNA repeats as well as in individuals with DM1. These results strongly support a role for CUGBP1 up-regulation in DM1 pathogenesis.

Imaging prostate cancer lymph node metastases with a multimodality contrast agent.

BACKGROUND: Methods to detect lymph node (LN) metastases in prostate cancer (PCa) are limited. Pelvic LN dissection is commonly performed during prostatectomy, but often followed by morbid complications. More refined methods for detecting LN invasion are needed. METHODS: We developed a dual-labeled targeting agent having a near-infrared (NIR) fluorophore for intraoperative guidance, and a conventional radiotracer for detection of LN metastasis. Nu/Nu mice were orthotopically implanted with DsRed-expressing human PCa (PC3) cells. Antibody (Ab) specific for epithelial cell adhesion molecule was conjugated to DOTA, IRDye 800CW, and radiolabeled with (64) Cu. Dual-labeled Ab was administered intravenously at 10-12 weeks post-implantation, and positron emission tomography/computed tomography (PET/CT) and fluorescence imaging were performed within 18-24 hr. RESULTS: Metastasis to lumbar LNs was detected by DsRed fluorescence imaging, as well as pathology, in 75% of mice having pathology-confirmed primary prostate tumors. These metastases were also detected by NIR fluorescence imaging. In some cases, metastases to sciatic, medial, renal, and axillary nodes were also detected. For all LNs examined, no significant differences were found between the percentages of metastases detected by NIR imaging (63%) and µPET/CT (64%) (P = 0.93), or between those detected by DsRed imaging (25%) and pathological examination (19%) (P = 0.12). CONCLUSION: This study demonstrates that a multimodality contrast agent is useful for early detection of metastatic disease, and has applications for intraoperative PCa treatment. Further agent optimization is necessary to enhance specificity, and provide validation for prostate and other LN metastasizing epithelial cancers.