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1.
Eur Thyroid J ; 11(3)2022 Jun 14.
Article in English | MEDLINE | ID: mdl-35521979

ABSTRACT

Objectives: There has been slow adoption of thyroid ultrasound guidelines with adherence rates as low as 30% and no population-based studies investigating adherence to guideline-based malignancy risk assessment. We therefore evaluated the impact of adherence to the 2015 ATA guidelines or 2017 ACR-TIRADS guidelines on the quality of thyroid ultrasound reports in our healthcare region. Methods: We reviewed 899 thyroid ultrasound reports of patients who received fine-needle aspiration biopsy and were diagnosed with Bethesda III or IV nodules or thyroid cancer. Ultrasounds were reported by radiology group 1, group 2, or other groups, and were divided into pre-2018 (before guideline adherence) or 2018 onwards. Reports were given a utility score (0-6) based on how many relevant nodule characteristics were included. Results: Group 1 had a pre-2018 utility score of 3.62 and 39.4% classification reporting rate, improving to 5.77 and 97.0% among 2018-onwards reports. Group 2 had a pre-2018 score of 2.8 and reporting rate of 11.5%, improving to 5.58 and 93.3%. Other radiology groups had a pre-2018 score of 2.49 and reporting rate of 32.2%, improving to 3.28 and 61.8%. Groups 1 and 2 had significantly higher utility scores and reporting rates in their 2018-onward reports when compared to other groups' 2018-onward reports, pre-2018 group 1 reports, and pre-2018 group 2 reports. Conclusions: Dedicated adherence to published thyroid ultrasound reporting guidelines can lead to improvements in report quality. This will reduce diagnostic ambiguity and improve clinician's decision-making, leading to overall reductions in unnecessary FNA biopsy and diagnostic surgery.

2.
Arch Environ Contam Toxicol ; 54(2): 187-94, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17762906

ABSTRACT

Static-renewal ecotoxicity trials monitored growth of Hydrilla verticillata in conjunction with exposure to Cylindrospermopsis raciborskii whole-cell extracts containing the cyanotoxin cylindrospermopsin (CYN). Maximum exposure concentrations were 400 microg L(-1) CYN over 14 days. The responses of Hydrilla to the treatments were variable according to the toxin concentrations and lengths of exposure. Plant deaths, chlorosis, and necrosis were not recorded from treated plants. However, Hydrilla experienced significant growth stimulation and redistribution of plant resources in conjunction with exposure to the whole-cell extracts. Root production was particularly impacted. The results of this study imply that root production could aid in reducing C. raciborskii cell concentrations and CYN toxicity. Results of chlorophyll analyses differed, indicating that CYN in whole-cell extracts might exert complex effects on photosynthesis. This is the first study to describe the responses of an aquatic macrophyte following exposure to C. raciborskii whole-cell extracts containing the cyanotoxin cylindrospermopsin.


Subject(s)
Bacterial Toxins/toxicity , Cylindrospermopsis/chemistry , Hydrocharitaceae/drug effects , Uracil/analogs & derivatives , Alkaloids , Chlorophyll/metabolism , Cyanobacteria Toxins , Hydrocharitaceae/growth & development , Hydrocharitaceae/metabolism , Plant Roots/drug effects , Plant Roots/growth & development , Plant Roots/metabolism , Uracil/toxicity
3.
Environ Toxicol ; 22(6): 550-8, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18000853

ABSTRACT

Histological examinations were made of cane toad (Bufo marinus) tadpoles after exposure to freeze-thawed Cylindrospermopsis raciborskii whole cell extracts and live C. raciborskii cultures containing sublethal concentrations of the blue-green algal toxin, cylindrospermopsin (CYN). Toxin exposure resulted in tissue injuries to multiple organs, with particular severity noted in the liver, intestine, nephric ducts and gill epithelia. The extent of cellular damage was similar across trials exposing tadpoles to aqueous and cell-bound toxins, despite unequal toxin concentrations being present in each. It was concluded that the presence of cell-bound toxin, which may be directly ingested via grazing, plays a crucial role in the exertion of histological effects in B. marinus. This work provides baseline information regarding the ecotoxicity of CYN toward amphibians. The range of cellular effects noted in CYN-exposed tadpoles suggests that toxic C. raciborskii blooms could represent considerable health risks to amphibian populations and indicate potentially far-reaching ecological impacts of toxic C. raciborskii blooms.


Subject(s)
Bufo marinus/physiology , Marine Toxins/toxicity , Uracil/analogs & derivatives , Alkaloids , Animals , Bacterial Toxins , Cyanobacteria , Cyanobacteria Toxins , Environmental Exposure , Larva/drug effects , Larva/physiology , Uracil/toxicity
4.
Qual Saf Health Care ; 14(3): e20, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15933294

ABSTRACT

BACKGROUND: In confronting an evolving crisis, the anaesthetist should consider the vascular catheter as a potential cause, abandoning assumptions that the device has been satisfactorily placed and is functioning correctly. OBJECTIVES: To examine the role of a previously described core algorithm "COVER ABCD-A SWIFT CHECK", supplemented by a specific sub-algorithm for vascular access problems, in the management of crises occurring in association with anaesthesia. METHODS: The potential performance of a structured approach was evaluated for each of the relevant incidents among the first 4000 reported to the Australian Incident Monitoring Study (AIMS). RESULTS: There were 128 incidents involving problems related to vascular access. The structured approach begins distally, checking the infusion device or fluid (12 incidents), moving proximally by way of the fluid giving line (10), the line deadspace (8), then the catheter/skin interface (65), and on to the peripheral vascular tree (3) and central venous space (23), and finally, the interface of the vascular access system and the attending staff (7). The approach was able to accommodate all the vascular access problems among the first 4000 incidents reported to AIMS. CONCLUSION: The approach has potential as an easily remembered and applied clinical tool to lead to early resolution of vascular access problems occurring during anaesthesia.


Subject(s)
Anesthesia/adverse effects , Anesthesiology/methods , Catheters, Indwelling/adverse effects , Emergencies , Intraoperative Complications/therapy , Algorithms , Anesthesiology/instrumentation , Anesthesiology/standards , Antineoplastic Agents/administration & dosage , Australia , Humans , Manuals as Topic , Medical Errors , Monitoring, Intraoperative , Risk Management , Task Performance and Analysis
5.
Infect Immun ; 69(4): 1983-93, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11254549

ABSTRACT

Bordetella pertussis, the causative agent of whooping cough, regulates expression of many virulence factors via a two-component signal transduction system encoded by the bvgAS regulatory locus. It has been shown by transcription activation kinetics that several of the virulence factors are differentially regulated. fha is transcribed within 10 min following a bvgAS-inducing signal, while prn is transcribed after 1 h and ptx is not transcribed until 2 to 4 h after induction. These genes therefore represent early, intermediate, and late classes of bvg-activated promoters, respectively. Although there have been many insightful studies into the mechanisms of BvgAS-mediated regulation, the role that differential regulation of virulence genes plays in B. pertussis pathogenicity has not been characterized. We provide evidence that alterations to the promoter regions of bvg-activated genes can alter the kinetic pattern of expression of these genes without changing steady-state transcription levels. In addition, B. pertussis strains containing these promoter alterations that express either ptx at an early time or fha at a late time demonstrate a significant reduction in their ability to colonize respiratory tracts in an intranasal mouse model of infection. These data suggest a role for differential regulation of bvg-activated genes, and therefore for the BvgAS regulatory system, in the pathogenicity of B. pertussis.


Subject(s)
Bacterial Proteins/genetics , Bordetella pertussis/pathogenicity , Fimbriae Proteins , Gene Expression Regulation, Bacterial , Transcription Factors/genetics , Animals , Bacterial Outer Membrane Proteins/genetics , CHO Cells , Cricetinae , Female , Lung/microbiology , Mice , Mice, Inbred BALB C , Promoter Regions, Genetic , Reverse Transcriptase Polymerase Chain Reaction , Virulence , Virulence Factors, Bordetella/genetics , Virulence Factors, Bordetella/toxicity
6.
Can J Surg ; 44(1): 25-32, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11220795

ABSTRACT

OBJECTIVE: To develop a collaborative approach for the treatment of gastrointestinal carcinoid tumours and carcinoid syndrome. PARTICIPANTS: Leaders in the medical, endocrine, radiologic and surgical treatment of carcinoid disease were selected to present papers at the Carcinoid Syndrome Symposium on Treatment Modalities for Gastrointestinal Carcinoid Tumours and participate in the workshop that followed. EVIDENCE: A multidisciplinary symposium with experts in the field of carcinoid syndrome was organized at the University of Calgary. Data presented, participation of the attendees and a review of the literature were used in the workshop to develop a collaborative approach to the management of carcinoid tumours. BENEFITS: Carcinoid tumours are rare and few centres have large experiences in their treatment. Before the development of this collaboration, patients with carcinoid tumours received a unidisciplinary approach depending on referral patterns. The development of a multidisciplinary neuroendocrine clinic helped to unify the approach to these patients, yet a consensus on the treatment of carcinoid tumours was lacking. The expertise at the symposium allowed for consensus and the development of treatment algorithms, including biochemical screening, radiographic localization and surgical intervention, for gastrointestinal carcinoid tumours. The role of medical and hormonal therapy after cytoreducion is presented. RECOMMENDATION: Patients with carcinoid tumours require a multidisciplinary approach to their care.


Subject(s)
Carcinoid Tumor/therapy , Gastrointestinal Neoplasms/therapy , Algorithms , Appendiceal Neoplasms/diagnostic imaging , Carcinoid Tumor/diagnostic imaging , Carcinoid Tumor/secondary , Gastrointestinal Neoplasms/diagnostic imaging , Gastrointestinal Neoplasms/secondary , Humans , Hydroxyindoleacetic Acid/urine , Liver Neoplasms/secondary , Syndrome , Tomography, X-Ray Computed
7.
Nat Struct Biol ; 7(1): 72-7, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10625431

ABSTRACT

The response of the internal dynamics of calcium-saturated calmodulin to the formation of a complex with a peptide model of the calmodulin-binding domain of the smooth muscle myosin light chain kinase has been studied using NMR relaxation methods. The backbone of calmodulin is found to be unaffected by the binding of the domain, whereas the dynamics of side chains are significantly perturbed. The changes in dynamics are interpreted in terms of a heterogeneous partitioning between structure (enthalpy) and dynamics (entropy). These data provide a microscopic view of the residual entropy of a protein in two functional states and suggest extensive enthalpy/entropy exchange during the formation of a protein-protein interface.


Subject(s)
Calmodulin/chemistry , Calmodulin/metabolism , Entropy , Peptide Fragments/chemistry , Peptide Fragments/metabolism , Amino Acid Sequence , Animals , Binding Sites , Calcium/metabolism , Chickens , Kinetics , Magnetic Resonance Spectroscopy , Models, Molecular , Molecular Sequence Data , Muscle, Smooth/enzymology , Myosin-Light-Chain Kinase/chemistry , Myosin-Light-Chain Kinase/metabolism , Pliability , Protein Binding , Protein Conformation , Thermodynamics , Water/metabolism
8.
J Immunol ; 164(3): 1333-9, 2000 Feb 01.
Article in English | MEDLINE | ID: mdl-10640747

ABSTRACT

HIV-1 infection of the brain results in chronic inflammation, contributing to the neuropathogenesis of HIV-1 associated neurologic disease. HIV-1-infected mononuclear phagocytes (MP) present in inflammatory infiltrates produce neurotoxins that mediate inflammation, dysfunction, and neuronal apoptosis. Neurologic disease is correlated with the relative number of MP in and around inflammatory infiltrates and not viral burden. It is unclear whether these cells also play a neuroprotective role. We show that the chemokine, fractalkine (FKN), is markedly up-regulated in neurons and neuropil in brain tissue from pediatric patients with HIV-1 encephalitis (HIVE) compared with those without HIVE, or that were HIV-1 seronegative. FKN receptors are expressed on both neurons and microglia in patients with HIVE. These receptors are localized to cytoplasmic structures which are characterized by a vesicular appearance in neurons which may be in cell-to-cell contact with MPs. FKN colocalizes with glutamate in these neurons. Similar findings are observed in brain tissue from an adult patient with HIVE. FKN is able to potently induce the migration of primary human monocytes across an endothelial cell/primary human fetal astrocyte trans-well bilayer, and is neuroprotective to cultured neurons when coadministered with either the HIV-1 neurotoxin platelet activating factor (PAF) or the regulatory HIV-1 gene product Tat. Thus focal inflammation in brain tissue with HIVE may up-regulate neuronal FKN levels, which in turn may be a neuroimmune modulator recruiting peripheral macrophages into the brain, and in a paracrine fashion protecting glutamatergic neurons.


Subject(s)
Brain/immunology , Chemokines, CX3C/biosynthesis , Encephalitis, Viral/immunology , HIV Infections/immunology , HIV-1/immunology , Macrophage Activation/immunology , Membrane Proteins/biosynthesis , Neurons/metabolism , Neuroprotective Agents/pharmacology , Adult , Animals , Astrocytes/immunology , Brain/metabolism , Brain/pathology , Cell Movement/immunology , Cells, Cultured , Chemokine CX3CL1 , Chemokines, CX3C/administration & dosage , Chemokines, CX3C/physiology , Child , Cytoplasm/metabolism , Encephalitis, Viral/pathology , Endothelium, Vascular/immunology , Gene Products, tat/administration & dosage , HIV Infections/pathology , HIV Seronegativity/immunology , Humans , Male , Membrane Proteins/administration & dosage , Membrane Proteins/physiology , Microglia/metabolism , Microglia/pathology , Monocytes/immunology , Neurons/pathology , Platelet Activating Factor/administration & dosage , Rats , Rats, Sprague-Dawley , Up-Regulation/immunology , tat Gene Products, Human Immunodeficiency Virus
9.
J Bacteriol ; 181(17): 5234-41, 1999 Sep.
Article in English | MEDLINE | ID: mdl-10464192

ABSTRACT

Bordetella pertussis, the causative agent of whooping cough, regulates expression of its virulence factors via a two-component signal transduction system encoded by the bvg regulatory locus. It has been shown by activation kinetics that several of the virulence factors are differentially regulated. fha is transcribed at 10 min following an inducing signal, while ptx is not transcribed until 2 to 4 h after the inducing signal. We present data indicating that prn is transcribed at 1 h, an intermediate time compared to those of fha and ptx. We have identified cis-acting sequences necessary for expression of prn in B. pertussis by using prn-lac fusions containing alterations in the sequence upstream of the prn open reading frame. In vitro transcription and DNase I footprinting analyses provided evidence to support our hypothesis that BvgA binds to this sequence upstream of prn to activate transcription from the promoter. Our genetic data indicate that the region critical for prn activation extends upstream to position -84. However, these data do not support the location of the prn transcription start site as previously published. We used a number of methods, including prn-lac fusions, reverse transcriptase PCR, and 5' rapid amplification of cDNA ends, to localize and identify the bvg-dependent 5' end of the prn transcript to the cytosine at -125 with respect to the published start site.


Subject(s)
Bacterial Outer Membrane Proteins/genetics , Bacterial Proteins/metabolism , Bordetella pertussis/genetics , Gene Expression Regulation, Bacterial , Promoter Regions, Genetic , Transcription Factors/metabolism , Virulence Factors, Bordetella , Base Sequence , Binding Sites , DNA, Bacterial , Genes, Bacterial , Kinetics , Molecular Sequence Data , Transcriptional Activation
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