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1.
Microb Genom ; 9(9)2023 09.
Article in English | MEDLINE | ID: mdl-37672388

ABSTRACT

For the last two decades, the human infection frequency of Escherichia coli O157 (O157) in Scotland has been 2.5-fold higher than in England and Wales. Results from national cattle surveys conducted in Scotland and England and Wales in 2014/2015 were combined with data on reported human clinical cases from the same time frame to determine if strain differences in national populations of O157 in cattle could be associated with higher human infection rates in Scotland. Shiga toxin subtype (Stx) and phage type (PT) were examined within and between host (cattle vs human) and nation (Scotland vs England and Wales). For a subset of the strains, whole genome sequencing (WGS) provided further insights into geographical and host association. All three major O157 lineages (I, II, I/II) and most sub-lineages (Ia, Ib, Ic, IIa, IIb, IIc) were represented in cattle and humans in both nations. While the relative contribution of different reservoir hosts to human infection is unknown, WGS analysis indicated that the majority of O157 diversity in human cases was captured by isolates from cattle. Despite comparable cattle O157 prevalence between nations, strain types were localized. PT21/28 (sub-lineage Ic, Stx2a+) was significantly more prevalent in Scottish cattle [odds ratio (OR) 8.7 (2.3-33.7; P<0.001] and humans [OR 2.2 (1.5-3.2); P<0.001]. In England and Wales, cattle had a significantly higher association with sub-lineage IIa strains [PT54, Stx2c; OR 5.6 (1.27-33.3); P=0.011] while humans were significantly more closely associated with sub-lineage IIb [PT8, Stx1 and Stx2c; OR 29 (4.9-1161); P<0.001]. Therefore, cattle farms in Scotland were more likely to harbour Stx2a+O157 strains compared to farms in E and W (P<0.001). There was evidence of limited cattle strain migration between nations and clinical isolates from one nation were more similar to cattle isolates from the same nation, with sub-lineage Ic (mainly PT21/28) exhibiting clear national association and evidence of local transmission in Scotland. While we propose the higher rate of O157 clinical cases in Scotland, compared to England and Wales, is a consequence of the nationally higher level of Stx2a+O157 strains in Scottish cattle, we discuss the multiple additional factors that may also contribute to the different infection rates between these nations.


Subject(s)
Escherichia coli O157 , Humans , Cattle , Animals , Escherichia coli O157/genetics , Wales/epidemiology , Scotland/epidemiology , England/epidemiology , Farms
2.
Sci Data ; 10(1): 477, 2023 07 21.
Article in English | MEDLINE | ID: mdl-37479849

ABSTRACT

The European Space Agency launched CryoSat-2 as the first European ice mission in 2010. Its advanced altimeter met primary objectives concerned with sea ice thickness and ice sheets. The value of Cryosat-2 data over global oceans was recognised, and operational products were developed via the CryoSat Ocean Processor (COP). The novel orbit of CryoSat-2 results in a denser coverage of sample points compared to other satellite altimeters. The National Oceanography Centre Sea Level Anomaly (NOCSLA) gridded product is based on interpolating Geophysical Ocean Products (GOP) using weights in space and time. GOP represents the highest quality operational ocean data. NOCSLA is a daily, »° sea level anomaly product covering non-coastal oceans between [60°N 60°S] and January 2011 to October 2020. The paper presents the methodology and scientific applications of NOCSLA. Oceanographic features observed are compared against products from other missions, including Rossby waves and El Niño signals. Results show good agreement with other products, confirming the value of Cryosat-2 data for ocean science and applications.

3.
Birth Defects Res ; 115(9): 933-944, 2023 05 15.
Article in English | MEDLINE | ID: mdl-37010372

ABSTRACT

A novel Group B Streptococcus (GBS) vaccine, based upon the GBS alpha-like surface proteins, is being developed by MinervaX for administration to pregnant women. The vaccine is intended to generate antibodies (IgG) capable of crossing the placenta, in order to passively immunize the baby and provide protection in utero and up to 3 months after birth. An initial vaccine candidate, GBS-NN (based on the N-terminal domains of Rib and AlphaC surface proteins) was replaced, due to insufficient cross-reactivity with the two other N-terminal proteins (Alp1 and Alp2/3), by a modified vaccine candidate designated GBS-NN/NN2 that included all four AlpNs. Preclinical studies raised no safety concerns and the subsequent Phase I clinical trial demonstrated that the vaccine was well tolerated and strongly immunogenic. As the vaccine is intended for use during pregnancy for maternal immunization, an embryofetal study in rats and a fertility and embryofetal study in rabbits were performed, in both cases using GBS-NN/NN2. Vaccination of female rats or rabbits did not adversely affect embryofetal development or survival in either species, or mating or fertility in rabbits. In both studies, the pregnant animals developed immune responses to GBS-NN and GBS-NN2 proteins and concentrations of antibodies to both fusion proteins were detected in the fetuses and in the amniotic fluid. Data generated during these reproductive studies indicated a suitable safety margin (approximately 40-fold clinical dose) considered appropriate to support a subsequent human trial of GBS-NN/NN2 administered in the second and third trimesters of pregnancy.


Subject(s)
Membrane Proteins , Vaccines , Animals , Female , Pregnancy , Rabbits , Rats , Antibodies, Bacterial , Immunization , Streptococcus agalactiae , Vaccination , Clinical Trials, Phase I as Topic , Humans
4.
Wellcome Open Res ; 7: 161, 2022.
Article in English | MEDLINE | ID: mdl-35865220

ABSTRACT

Background: Mobility restrictions prevent the spread of infections to disease-free areas, and early in the coronavirus disease 2019 (COVID-19) pandemic, most countries imposed severe restrictions on mobility as soon as it was clear that containment of local outbreaks was insufficient to control spread. These restrictions have adverse impacts on the economy and other aspects of human health, and it is important to quantify their impact for evaluating their future value. Methods: Here we develop Scotland Coronavirus transmission Model (SCoVMod), a model for COVID-19 in Scotland, which presents unusual challenges because of its diverse geography and population conditions. Our fitted model captures spatio-temporal patterns of mortality in the first phase of the epidemic to a fine geographical scale. Results: We find that lockdown restrictions reduced transmission rates down to an estimated 12\% of its pre-lockdown rate. We show that, while the timing of COVID-19 restrictions influences the role of the transmission rate on the number of COVID-related deaths, early reduction in long distance movements does not. However, poor health associated with deprivation has a considerable association with mortality; the Council Area (CA) with the greatest health-related deprivation was found to have a mortality rate 2.45 times greater than the CA with the lowest health-related deprivation considering all deaths occurring outside of carehomes. Conclusions: We find that in even an early epidemic with poor case ascertainment, a useful spatially explicit model can be fit with meaningful parameters based on the spatio-temporal distribution of death counts. Our simple approach is useful to strategically examine trade-offs between travel related restrictions and physical distancing, and the effect of deprivation-related factors on outcomes.

5.
J Med Internet Res ; 24(3): e31684, 2022 03 09.
Article in English | MEDLINE | ID: mdl-35262495

ABSTRACT

For over a decade, Scotland has implemented and operationalized a system of Safe Havens, which provides secure analytics platforms for researchers to access linked, deidentified electronic health records (EHRs) while managing the risk of unauthorized reidentification. In this paper, a perspective is provided on the state-of-the-art Scottish Safe Haven network, including its evolution, to define the key activities required to scale the Scottish Safe Haven network's capability to facilitate research and health care improvement initiatives. A set of processes related to EHR data and their delivery in Scotland have been discussed. An interview with each Safe Haven was conducted to understand their services in detail, as well as their commonalities. The results show how Safe Havens in Scotland have protected privacy while facilitating the reuse of the EHR data. This study provides a common definition of a Safe Haven and promotes a consistent understanding among the Scottish Safe Haven network and the clinical and academic research community. We conclude by identifying areas where efficiencies across the network can be made to meet the needs of population-level studies at scale.


Subject(s)
Electronic Health Records , Privacy , Humans , Scotland
6.
Biochemistry ; 57(12): 1907-1916, 2018 03 27.
Article in English | MEDLINE | ID: mdl-29350905

ABSTRACT

The parasitoid wasp Ampulex compressa injects venom directly into the brain and subesophageal ganglion of the cockroach Periplaneta americana, inducing a 7 to 10 day lethargy termed hypokinesia. Hypokinesia presents as a significant reduction in both escape response and spontaneous walking. We examined aminergic and peptidergic components of milked venom with HPLC and MALDI-TOF mass spectrometry. HPLC coupled with electrochemical detection confirmed the presence of dopamine in milked venom, while mass spectrometry revealed that the venom gland and venom sac have distinct peptide profiles, with milked venom predominantly composed of venom sac peptides. We isolated and characterized novel α-helical, amphipathic venom sac peptides that constitute a new family of venom toxins termed ampulexins. Injection of the most abundant venom peptide, ampulexin 1, into the subesophageal ganglion of cockroaches resulted in a short-term increase in escape threshold. Neither milked venom nor venom peptides interfered with growth of Escherichia coli or Bacillus thuringiensis on agar plates, and exposure to ampulexins or milked venom did not induce cell death in Chinese hamster ovary cells (CHO-K1) or Hi5 cells ( Trichoplusia ni).


Subject(s)
Insect Proteins/chemistry , Peptides/chemistry , Wasp Venoms/chemistry , Wasps/chemistry , Animals , Insect Proteins/pharmacology , Peptides/pharmacology , Periplaneta , Wasp Venoms/pharmacology
7.
J Neuroinflammation ; 13(1): 267, 2016 10 12.
Article in English | MEDLINE | ID: mdl-27733171

ABSTRACT

BACKGROUND: Acute intoxication with organophosphorus (OP) cholinesterase inhibitors can trigger convulsions that progress to life-threatening status epilepticus. Survivors face long-term morbidity including mild-to-severe decline in memory. It is posited that neuroinflammation plays a key role in the pathogenesis of OP-induced neuropsychiatric deficits. Rigorous testing of this hypothesis requires preclinical models that recapitulate relevant phenotypic outcomes. Here, we describe a rat model of acute intoxication with the OP diisopropylfluorophosphate (DFP) that exhibits persistent neuroinflammation and cognitive impairment. METHODS: Neuroinflammation, neurodegeneration, and cognitive function were compared in adult male Sprague Dawley rats injected with an acutely toxic dose of DFP vs. vehicle controls at multiple time points up to 36 days post-exposure. Neuroinflammation was quantified using immunohistochemical biomarkers of microglia (ionized calcium-binding adapter molecule 1, IBA1) and activated astrocytes (glial fibrillary acidic protein, GFAP) and positron emission tomography (PET) imaging of [11C]-(R)-PK11195, a ligand for the 18-kDa mitochondrial membrane translocator protein (TSPO). FluoroJade-B staining was used to assess neurodegeneration; Pavlovian conditioning, to assess cognitive function. RESULTS: Animals exhibited moderate-to-severe seizures within minutes of DFP injection that continued for up to 6 h post-injection. As indicated by IBA1 and GFAP immunoreactivity and by PET imaging of TSPO, acute DFP intoxication triggered neuroinflammation in the hippocampus and cortex during the first 3 days that peaked at 7 days and persisted to 21 days post-exposure in most animals. Neurodegeneration was detected in multiple brain regions from 1 to 14 days post-exposure. All DFP-intoxicated animals exhibited significant deficits in contextual fear conditioning at 9 and 20 days post-exposure compared to vehicle controls. Whole-brain TSPO labeling positively correlated with seizure severity score, but did not correlate with performance in the contextual fear-conditioning task. CONCLUSIONS: We describe a preclinical model in which acute DFP intoxication causes seizures, persistent neuroinflammation, neurodegeneration, and memory impairment. The extent of the neuroinflammatory response is influenced by seizure severity. However, the observation that a subset of animals with moderate seizures and minimal TSPO labeling exhibited cognitive deficits comparable to those of animals with severe seizures and significant TSPO labeling suggests that DFP may impair learning and memory circuitry via mechanisms independent of seizures or neuroinflammation.


Subject(s)
Cholinesterase Inhibitors/toxicity , Cognitive Dysfunction/chemically induced , Encephalitis/chemically induced , Isoflurophate/toxicity , Animals , Calcium-Binding Proteins/metabolism , Carrier Proteins/metabolism , Cognitive Dysfunction/diagnostic imaging , Conditioning, Classical/drug effects , Encephalitis/diagnostic imaging , Exploratory Behavior/drug effects , Glial Fibrillary Acidic Protein/metabolism , Magnetic Resonance Imaging , Male , Microfilament Proteins/metabolism , Positron-Emission Tomography , Rats , Rats, Sprague-Dawley , Receptors, GABA-A/metabolism , Regression Analysis , Time Factors
8.
Sci Rep ; 6: 20649, 2016 Feb 09.
Article in English | MEDLINE | ID: mdl-26857150

ABSTRACT

Genome-wide experiments to map the DNA-binding locations of transcription-associated factors (TFs) have shown that the number of genes bound by a TF far exceeds the number of possible direct target genes. Distinguishing functional from non-functional binding is therefore a major challenge in the study of transcriptional regulation. We hypothesized that functional targets can be discovered by correlating binding and expression profiles across multiple experimental conditions. To test this hypothesis, we obtained ChIP-seq and RNA-seq data from matching cell types from the human ENCODE resource, considered promoter-proximal and distal cumulative regulatory models to map binding sites to genes, and used a combination of linear and non-linear measures to correlate binding and expression data. We found that a high degree of correlation between a gene's TF-binding and expression profiles was significantly more predictive of the gene being differentially expressed upon knockdown of that TF, compared to using binding sites in the cell type of interest only. Remarkably, TF targets predicted from correlation across a compendium of cell types were also predictive of functional targets in other cell types. Finally, correlation across a time course of ChIP-seq and RNA-seq experiments was also predictive of functional TF targets in that tissue.


Subject(s)
DNA-Binding Proteins , DNA , Gene Expression Regulation , Nucleotide Mapping/methods , Response Elements , DNA/chemistry , DNA/metabolism , DNA-Binding Proteins/chemistry , DNA-Binding Proteins/metabolism , Genome-Wide Association Study , Humans , Organ Specificity
9.
Toxicol Appl Pharmacol ; 281(2): 185-94, 2014 Dec 01.
Article in English | MEDLINE | ID: mdl-25448683

ABSTRACT

Tetramethylenedisulfotetramine (TETS) is a potent convulsant poison for which there is currently no approved antidote. The convulsant action of TETS is thought to be mediated by inhibition of type A gamma-aminobutyric acid receptor (GABAAR) function. We, therefore, investigated the effects of post-exposure administration of diazepam, a GABAAR positive allosteric modulator, on seizure activity, death and neuroinflammation in adult male Swiss mice injected with a lethal dose of TETS (0.15mg/kg, ip). Administration of a high dose of diazepam (5mg/kg, ip) immediately following the second clonic seizure (approximately 20min post-TETS injection) effectively prevented progression to tonic seizures and death. However, this treatment did not prevent persistent reactive astrogliosis and microglial activation, as determined by GFAP and Iba-1 immunoreactivity and microglial cell morphology. Inhibition of soluble epoxide hydrolase (sEH) has been shown to exert potent anti-inflammatory effects and to increase survival in mice intoxicated with other GABAAR antagonists. The sEH inhibitor TUPS (1mg/kg, ip) administered immediately after the second clonic seizure did not protect TETS-intoxicated animals from tonic seizures or death. Combined administration of diazepam (5mg/kg, ip) and TUPS (1mg/kg, ip, starting 1h after diazepam and repeated every 24h) prevented TETS-induced lethality and influenced signs of neuroinflammation in some brain regions. Significantly decreased microglial activation and enhanced reactive astrogliosis were observed in the hippocampus, with no changes in the cortex. Combining an agent that targets specific anti-inflammatory mechanisms with a traditional antiseizure drug may enhance treatment outcome in TETS intoxication.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Anticonvulsants/administration & dosage , Brain/drug effects , Bridged-Ring Compounds , Diazepam/administration & dosage , Encephalitis/prevention & control , Enzyme Inhibitors/administration & dosage , Epoxide Hydrolases/antagonists & inhibitors , GABA Modulators/administration & dosage , Phenylurea Compounds/administration & dosage , Piperidines/administration & dosage , Seizures/prevention & control , Animals , Brain/enzymology , Brain/physiopathology , Brain Waves/drug effects , Disease Models, Animal , Drug Administration Schedule , Drug Therapy, Combination , Electroencephalography , Encephalitis/chemically induced , Encephalitis/enzymology , Encephalitis/physiopathology , Epoxide Hydrolases/metabolism , Male , Mice , Seizures/chemically induced , Seizures/enzymology , Seizures/physiopathology , Time Factors
10.
Neurotoxicology ; 33(3): 575-84, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22342984

ABSTRACT

Organophosphorus (OP) nerve agents and pesticides inhibit acetylcholinesterase (AChE), and this is thought to be a primary mechanism mediating the neurotoxicity of these compounds. However, a number of observations suggest that mechanisms other than or in addition to AChE inhibition contribute to OP neurotoxicity. There is significant experimental evidence that acute OP intoxication elicits a robust inflammatory response, and emerging evidence suggests that chronic repeated low-level OP exposure also upregulates inflammatory mediators. A critical question that is just beginning to be addressed experimentally is the pathophysiologic relevance of inflammation in either acute or chronic OP intoxication. The goal of this article is to provide a brief review of the current status of our knowledge linking inflammation to OP intoxication, and to discuss the implications of these findings in the context of therapeutic and diagnostic approaches to OP neurotoxicity.


Subject(s)
Inflammation/chemically induced , Neurons/drug effects , Neurotoxicity Syndromes/etiology , Organophosphorus Compounds/toxicity , Animals , Humans , Inflammation/immunology , Inflammation/pathology , Inflammation Mediators/metabolism , Neurons/immunology , Neurons/pathology , Neurotoxicity Syndromes/immunology , Neurotoxicity Syndromes/pathology , Risk Assessment , Risk Factors
11.
J Pharmacol Exp Ther ; 341(2): 435-46, 2012 May.
Article in English | MEDLINE | ID: mdl-22328574

ABSTRACT

Tetramethylenedisulfotetramine (tetramine; TETS) is a potent convulsant poison that is considered to be a chemical threat agent. To provide a basis for the investigation of antidotes for TETS-induced seizures, we characterized the convulsant activity of TETS in mice and rats when administered by the intraperitoneal, intravenous, oral, and intraventricular routes as a single acute dose and with repeated sublethal doses. In mice, parenteral and oral TETS caused immobility, myoclonic body jerks, clonic seizures of the forelimbs and/or hindlimbs, tonic seizures, and death. The CD50 values for clonic and tonic seizures after oral administration were 0.11 and 0.22 mg/kg, respectively. Intraventricular administration of TETS (5-100 µg) in rats also caused clonic-tonic seizures and death. In mice, repeated sublethal doses of TETS at intervals of 2, 24, and 48 h failed to result in the development of persistent enhanced seizure responsivity ("kindling") as was observed with repeated pentylenetetrazol treatment. In mice, sublethal doses of TETS that produced clonic seizures did not cause observable structural brain damage as assessed with routine histology and Fluoro-Jade B staining 7 days after treatment. However, 1 to 3 days after a single convulsant dose of TETS the expression of glial fibrillary acidic protein, an astrocyte marker, and ionized calcium binding adaptor molecule 1, a microglia marker, were markedly increased in cortex and hippocampus. Although TETS doses that are compatible with survival are not associated with overt evidence of cellular injury or neurodegeneration, there is transient reactive astrocytosis and microglial activation, indicating that brain inflammatory responses are provoked.


Subject(s)
Bridged-Ring Compounds/toxicity , Convulsants/toxicity , Seizures/chemically induced , Seizures/metabolism , Animals , Astrocytes/drug effects , Astrocytes/metabolism , Calcium-Binding Proteins/metabolism , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Extremities , Glial Fibrillary Acidic Protein/metabolism , Gliosis/chemically induced , Gliosis/metabolism , Hippocampus/drug effects , Hippocampus/metabolism , Male , Mice , Microfilament Proteins/metabolism , Microglia/drug effects , Microglia/metabolism , Pentylenetetrazole/pharmacology , Picrotoxin/adverse effects , Rats , Rats, Sprague-Dawley
12.
Toxicon ; 59(2): 320-8, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22085538

ABSTRACT

The emerald jewel wasp, Ampulex compressa, exploits the American cockroach, Periplaneta americana, as a host for its progeny. The wasp subdues the host by stinging directly into the brain and subesophageal ganglion, inducing long-term hypokinesia. The hypokinesic host lacks normal escape behavior and motivation to walk, making it easy for subjugation by the wasp. The mechanism underlying hypokinesia induction is not known, but depletion of monoamines induces behavior resembling venom-induced hypokinesia. To test whether amine depletion occurs in stung animals, we used high-performance liquid chromatography with electrochemical detection (HPLC-ED) to measure quantitatively amine levels in the central nervous system. Our data show clearly that levels of dopamine, serotonin, octopamine and tyramine remain unchanged in stung animals, whereas animals treated with reserpine exhibited marked depletion of all amines sampled. Furthermore, stung animals treated with reserpine show depletion of amines, demonstrating that envenomation also does not interfere with amine release. These results show that hypokinesia induced by Ampulex venom does not result from amine depletion or inability to release monoamines in the central nervous system.


Subject(s)
Biogenic Amines/analysis , Central Nervous System/drug effects , Periplaneta/chemistry , Wasp Venoms/metabolism , Animals , Chromatography, High Pressure Liquid/methods , Dopamine/blood , Host-Parasite Interactions , Hymenoptera/chemistry , Hypokinesia/chemically induced , Hypokinesia/pathology , Male , Octopamine/blood , Periplaneta/parasitology , Reserpine/therapeutic use , Serotonin/blood , Tyramine/blood
13.
J Ultrasound Med ; 28(5): 651-6, 2009 May.
Article in English | MEDLINE | ID: mdl-19389904

ABSTRACT

OBJECTIVE: We describe a case series constituting the first clinical trial by intravenous (IV) team nurses using the sonic flashlight (SF) for ultrasound guidance of peripherally inserted central catheter (PICC) placement. METHODS: Two IV team nurses with more than 10 years of experience with placing PICCs and 3 to 6 years of experience with ultrasound attempted to place PICCs under ultrasound guidance in patients requiring long-term IV access. One of two methods of ultrasound guidance was used: conventional ultrasound (CUS; 60 patients) or a new device called the SF (44 patients). The number of needle punctures required to gain IV access was recorded for each patient. RESULTS: In both methods, 87% of the cases resulted in successful venous access on the first attempt. The average number of needle sticks per patient was 1.18 for SF-guided procedures compared with 1.20 for CUS-guided procedures. No significant difference was found in the distribution of the number of attempts between the two methods. Anecdotal comments by the nurses indicated the comparative ease of use of the SF display, although the relatively small scale of the SF image compared with the CUS image was also noted. CONCLUSIONS: We have shown that the SF is a safe and effective device for guidance of PICC placement in the hands of experienced IV team nurses. The advantage of placing the ultrasound image at its actual location must be balanced against the relatively small scale of the SF image.


Subject(s)
Catheterization, Central Venous/instrumentation , Lighting/instrumentation , Nursing/instrumentation , Ultrasonography/instrumentation , Adult , Aged , Catheterization, Central Venous/methods , Female , Humans , Male , Middle Aged , Pilot Projects
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