Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 28
Filter
1.
Horm Res Paediatr ; 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38861933

ABSTRACT

The 49th Annual Conference of the International Society of Pediatric and Adolescent Diabetes (ISPAD), held from October 18 to 21, 2023, in Rotterdam, Netherlands, showcased significant advancements and diversity in paediatric and adolescent diabetes research and clinical innovations. The conference, renowned for its global impact, brought together experts to discuss cutting-edge developments in the field. Highlights from the plenary sessions included ground-breaking research on immunotherapies and diabetes technologies and offering new insights into personalised treatment approaches. Keynote speakers emphasised the importance of early diagnosis, prevention and the potential of novel biomarkers in predicting disease progression. The symposia covered a broad spectrum of topics, from advancements in continuous glucose monitoring technologies to the latest in hybrid closed loop systems which promise to revolutionise diabetes management for young patients.

2.
Pilot Feasibility Stud ; 8(1): 196, 2022 Sep 03.
Article in English | MEDLINE | ID: mdl-36057634

ABSTRACT

BACKGROUND: Malignant pleural mesothelioma (MPM) is an aggressive thoracic malignancy with a poor prognosis. Systemic immunotherapy is an effective frontline treatment for MPM, and there is a scientific rationale supporting the possible efficacy of local, i.e. intra-pleural immune modulators. Trial of intra-pleural bacterial immunotherapy (TILT) investigated the feasibility of performing a randomised trial of intra-pleural bacterial immunotherapy in people with MPM, using the trials within cohorts (TwiC) methodology. METHODS: TILT was a multicentre, three-armed, randomised, feasibility TwiC of intra-pleural OK432, BCG, or usual care in people with MPM. Eligible participants were identified from within the ASSESS-meso study, a prospective, longitudinal, observational cohort study, and were randomly selected to be offered a single dose of OK432 or BCG, via an indwelling pleural catheter. The primary outcome was feasibility, evaluated against prespecified recruitment, attrition and data completeness targets. The acceptability of trial processes and interventions was assessed during qualitative interviews with participants and family members at the end of the trial. TILT was registered prospectively on the European Clinical Trials Registry (EudraCT number 2016-004,727-23) and the ISRCTN Register on 04 December 2017. RESULTS: Seven participants were randomised from a planned sample size of 12; thus, the 66% recruitment rate target was not met. Two participants withdrew after randomisation, breaching the pre-stated attrition threshold of 10%. It was not possible to maintain blinding of control participants, which negated a fundamental tenet of the TwiC design. The trial processes and methodology were generally acceptable to participants and relatives, despite several recipients of intra-pleural bacterial agents experiencing significant local and systemic inflammatory responses. CONCLUSION: It was possible to design a clinical trial of an investigational medicinal product based on the TwiC design and to obtain the necessary regulatory approvals. However, whilst acceptable to participants and relatives, the TwiC design was not a feasible method of investigating intra-pleural bacterial immunotherapy in people with MPM. Future trials investigating this topic should consider the eligibility constraints and recruitment difficulties encountered. TRIAL REGISTRATION: TILT was registered prospectively on the European Clinical Trials Registry (EudraCT number 2016-004727-23 ) and the ISRCTN Register ( 10432197 ) on 04 December 2017.

3.
Diabet Med ; 39(7): e14863, 2022 07.
Article in English | MEDLINE | ID: mdl-35488481

ABSTRACT

Hybrid closed-loop (HCL) systems are characterised by integrating continuous glucose monitoring (CGM) with insulin pumps which automate insulin delivery via specific algorithms and user-initiated insulin delivery. The aim of the study was to evaluate the effectiveness of HCLs on Hba1c, time-in-range (TIR), time in hypoglycaemia, fear of hypoglycaemia, sleep and quality of life measure in children and young people (CYP) with T1D and their carers. Data on HbA1c, TIR and hypoglycaemia frequency were reviewed at baseline prior to starting HCL and 3 months after commencement. As part of clinical care, all patients and carers were provided with key education on the use of the HCL system by trained diabetes healthcare professionals. CYP aged 12 years and above independently completed the validated Hypoglycaemia Fear Survey (HFS). Parents of patients <12 were asked to complete a modified version of the HFS-Parent (HFS-P) survey. There were 39 CYP (22 men) with T1D included with a mean age of 11.8 ± 4.4 at commencement of HCL. Median duration of diabetes was 3.8 years (interquartile range 1.3-6.0). There were 55% of patients who were prepubertal at the time of HCL commencement. 91% were on the Control-IQ system and 9% on the CamAPS FX system. HCL use demonstrated significant improvements at 3 months in the following: HbA1c in mmol/mol (63.0 vs. 56.6, p = 0.03), TIR (50.5 vs. 67.0, p = 0.001) and time in hypoglycaemia (4.3% vs. 2.8%, p = 0.004). HFS scores showed improved behaviour (34.0 vs. 27.5.9, p = 0.02) and worry (40.2 vs. 31.6, p = 0.03), and HFS-P scores also showed improved behaviour (p < 0.001) and worry (p = 0.01). Our study shows that HCL at 3 months improves glucose control, diabetes management and quality of life measures such as fear and worry of hypoglycaemia for CYP and carers.


Subject(s)
Diabetes Mellitus, Type 1 , Hypoglycemia , Adolescent , Blood Glucose , Blood Glucose Self-Monitoring , Caregivers , Child , Diabetes Mellitus, Type 1/drug therapy , Glycated Hemoglobin/analysis , Humans , Hypoglycemia/chemically induced , Hypoglycemia/prevention & control , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Insulin Infusion Systems , Male , Quality of Life
4.
Dev Psychobiol ; 63(2): 350-363, 2021 03.
Article in English | MEDLINE | ID: mdl-32658309

ABSTRACT

Maternal hypothalamic-pituitary-adrenal axis activity may prenatally program sex-specific stress-response pathways. We investigated associations between maternal cortisol during pregnancy and infant parasympathetic responsivity to stress among 204 mother-infant pairs. Cortisol indices included 3rd trimester hair cortisol, as well as diurnal slope and area under the curve, derived from saliva samples collected during pregnancy. Mother-infant dyads participated in the Repeated Still-Face Paradigm (SFP-R) at age 6 months. We calculated respiration-adjusted respiratory sinus arrhythmia (RSAc ), an indicator of parasympathetic activation, from infant respiration and cardiac activity measured during the SFP-R. We used multivariable linear mixed models to examine each cortisol index in relation to infant RSAc and investigated sex differences using cross-product terms. Diurnal cortisol indices were not associated with RSAc . There was no association between hair cortisol and baseline RSAc . However, hair cortisol was associated with sex-specific changes in RSAc over the SFP-R such that, among girls, parasympathetic withdrawal was reduced with increasing prenatal exposure to cortisol. Consistently higher levels of prenatal cortisol exposure may lead to dampened parasympathetic responsivity to stress during infancy, particularly among girls. Maternal hair cortisol may be particularly valuable for studying the effects of prenatal cortisol exposure on infant autonomic reactivity.


Subject(s)
Hydrocortisone , Prenatal Exposure Delayed Effects , Female , Humans , Hypothalamo-Hypophyseal System , Infant , Male , Mothers , Pituitary-Adrenal System , Pregnancy , Saliva , Stress, Psychological
5.
J Nucl Med ; 58(12): 1991-1996, 2017 12.
Article in English | MEDLINE | ID: mdl-28611243

ABSTRACT

There is a large unmet need for a simple, accurate, noninvasive, quantitative, and high-resolution imaging modality to detect lung fibrosis at early stage and to monitor disease progression. Overexpression of collagen is a hallmark of organ fibrosis. Here, we describe the optimization of a collagen-targeted PET probe for staging pulmonary fibrosis. Methods: Six peptides were synthesized, conjugated to a copper chelator, and radiolabeled with 64Cu. The collagen affinity of each probe was measured in a plate-based assay. The pharmacokinetics and metabolic stability of the probes were studied in healthy rats. The capacity of these probes to detect and stage pulmonary fibrosis in vivo was assessed in a mouse model of bleomycin-induced fibrosis using PET imaging. Results: All probes exhibited affinities in the low micromolar range (1.6 µM < Kd < 14.6 µM) and had rapid blood clearance. The probes showed 2- to 8-fold-greater uptake in the lungs of bleomycin-treated mice than sham-treated mice, whereas the distribution in other organs was similar between bleomycin-treated and sham mice. The probe 64Cu-CBP7 showed the highest uptake in fibrotic lungs and the highest target-to-background ratios. The superiority of 64Cu-CBP7 was traced to a much higher metabolic stability compared with the other probes. The specificity of 64Cu-CBP7 for collagen was confirmed by comparison with a nonbinding isomer. Conclusion:64Cu-CBP7 is a promising candidate for in vivo imaging of pulmonary fibrosis.


Subject(s)
Collagen/metabolism , Pulmonary Fibrosis/diagnostic imaging , Radiopharmaceuticals/chemical synthesis , Animals , Antibiotics, Antineoplastic , Bleomycin , Chelating Agents , Copper Radioisotopes , Disease Progression , Male , Mice , Mice, Inbred C57BL , Positron-Emission Tomography , Pulmonary Fibrosis/chemically induced , Pulmonary Fibrosis/metabolism , Radiopharmaceuticals/pharmacokinetics , Rats , Tissue Distribution
6.
Sci Transl Med ; 9(384)2017 04 05.
Article in English | MEDLINE | ID: mdl-28381537

ABSTRACT

Pulmonary fibrosis is scarring of the lungs that can arise from radiation injury, drug toxicity, environmental or genetic causes, and for unknown reasons [idiopathic pulmonary fibrosis (IPF)]. Overexpression of collagen is a hallmark of organ fibrosis. We describe a peptide-based positron emission tomography (PET) probe (68Ga-CBP8) that targets collagen type I. We evaluated 68Ga-CBP8 in vivo in the bleomycin-induced mouse model of pulmonary fibrosis. 68Ga-CBP8 showed high specificity for pulmonary fibrosis and high target/background ratios in diseased animals. The lung PET signal and lung 68Ga-CBP8 uptake (quantified ex vivo) correlated linearly (r2 = 0.80) with the amount of lung collagen in mice with fibrosis. We further demonstrated that the 68Ga-CBP8 probe could be used to monitor response to treatment in a second mouse model of pulmonary fibrosis associated with vascular leak. Ex vivo analysis of lung tissue from patients with IPF supported the animal findings. These studies indicate that 68Ga-CBP8 is a promising candidate for noninvasive imaging of human pulmonary fibrosis.


Subject(s)
Collagen Type I/metabolism , Molecular Probes/chemistry , Positron-Emission Tomography , Pulmonary Fibrosis/diagnostic imaging , Pulmonary Fibrosis/diagnosis , Animals , Bleomycin , Capillary Permeability , Disease Models, Animal , Disease Progression , Gallium Radioisotopes , Humans , Idiopathic Pulmonary Fibrosis/pathology , Kidney/metabolism , Lung/pathology , Male , Mice, Inbred C57BL , Pulmonary Fibrosis/pathology
7.
Hepatology ; 65(3): 1015-1025, 2017 03.
Article in English | MEDLINE | ID: mdl-28039886

ABSTRACT

Hepatic fibrosis is associated with an overproduction of matrix proteins and a pathological increase of liver stiffness. Noninvasive magnetic resonance (MR) quantification of matrix can be assessed with a collagen-binding molecular MR probe and stiffness by MR elastography, complementary techniques. This study used both imaging techniques to more accurately stage hepatic fibrosis in a rat model. Thirty rats with varying levels of diethylnitrosamine-induced liver fibrosis were imaged before and 45 minutes after injection of collagen-specific probe EP-3533. MR elastography was performed in the same imaging session. Changes in liver relaxation rate post-EP-3533 and liver stiffness were compared to the collagen proportional area determined by histology and to Ishak scoring using receiver operating characteristic analysis. Collagen imaging was most sensitive to early fibrosis, while elastography was more sensitive to advanced fibrosis. This complementary feature enabled the formulation of a composite model using multivariate analysis of variance. This model incorporated the discriminating advantages of both MR techniques, resulting in more accurate staging throughout fibrotic progression. CONCLUSION: Collagen molecular MR imaging is complementary to MR elastography, and combining the two techniques in a single exam leads to increased diagnostic accuracy for all stages of fibrosis. (Hepatology 2017;65:1015-1025).


Subject(s)
Elasticity Imaging Techniques/methods , Liver Cirrhosis/pathology , Magnetic Resonance Imaging/methods , Multimodal Imaging/methods , Analysis of Variance , Animals , Biopsy, Needle , Diethylnitrosamine/pharmacology , Disease Models, Animal , Immunohistochemistry , Liver Cirrhosis/chemically induced , Liver Cirrhosis/diagnosis , Male , Multivariate Analysis , Random Allocation , Rats , Rats, Wistar , Severity of Illness Index
8.
J Atten Disord ; 20(5): 383-9, 2016 May.
Article in English | MEDLINE | ID: mdl-23382575

ABSTRACT

OBJECTIVE: This study examined whether ADHD was an independent contributor to grade retention when adjusting for IQ, learning disorders, and social class. METHOD: Outcome data was from participants in studies at Massachusetts General Hospital (n= 404 ADHD,n= 349 controls) who underwent psychiatric interviews, socioeconomic status measures, and IQ testing. RESULTS: 28% of individuals with ADHD repeated a grade compared with 7% of controls (p< .001). Among participants with ADHD, social class, and IQ were significant predictors of high school dropout or repeated grade. An interaction effect of ADHD and gender was also found with females with ADHD having a higher risk ratio for repeated grade/dropout compared with males with ADHD. CONCLUSION: Participants with ADHD were significantly more likely to repeat a grade, adjusting for all other variables indicating the critical importance of early identification of ADHD to help mitigate adverse educational outcomes.


Subject(s)
Attention Deficit Disorder with Hyperactivity/psychology , Intelligence , Student Dropouts/psychology , Student Dropouts/statistics & numerical data , Adolescent , Adult , Attention Deficit Disorder with Hyperactivity/diagnosis , Attention Deficit Disorder with Hyperactivity/epidemiology , Child , Comorbidity , Female , Humans , Learning Disabilities , Male , Massachusetts/epidemiology , Middle Aged , Odds Ratio , Risk Factors , Schools , Social Class , Socioeconomic Factors
9.
J Nucl Med ; 56(10): 1587-92, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26251420

ABSTRACT

UNLABELLED: We recently showed the high target specificity and favorable imaging properties of 64Cu and Al18F PET probes for noninvasive imaging of thrombosis. Here, our aim was to evaluate new derivatives labeled with either with 68Ga, 111In, or 99mTc as thrombus imaging agents for PET and SPECT. In this study, the feasibility and potential of these probes for thrombus imaging was assessed in detail in 2 animal models of arterial thrombosis. The specificity of the probes was further evaluated using a triple-isotope approach with multimodal SPECT/PET/CT imaging. METHODS: Radiotracers were synthesized using a known fibrin-binding peptide conjugated to 1,4,7-triazacyclononane,1-glutaric acid-4,7-acetic acid (NODAGA), 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid monoamide (DOTA-MA), or a diethylenetriamine ligand (DETA-propanoic acid [PA]), followed by labeling with 68Ga (FBP14, 68Ga-NODAGA), 111In (FBP15, 111In-DOTA-MA), or 99mTc (FBP16, 99mTc(CO)3-DETA-PA), respectively. PET or SPECT imaging, biodistribution, pharmacokinetics, and metabolic stability were evaluated in rat models of mural and occlusive carotid artery thrombosis. In vivo target specificity was evaluated by comparing the distribution of the SPECT and PET probes with preformed 125I-labeled thrombi and with a nonbinding control probe using SPECT/PET/CT imaging. RESULTS: All 3 radiotracers showed affinity similar to soluble fibrin fragment DD(E) (inhibition constant=0.53-0.83 µM). After the kidneys, the highest uptake of 68Ga-FBP14 and 111In-FBP15 was in the thrombus (1.0±0.2 percentage injected dose per gram), with low off-target accumulation. Both radiotracers underwent fast systemic elimination (half-life, 8-15 min) through the kidneys, which led to highly conspicuous thrombi on PET and SPECT images. 99mTc-FBP16 displayed low target uptake and distribution consistent with aggregation or degradation. Triple-isotope imaging experiments showed that both 68Ga-FBP14 and 111In-FBP15, but not the nonbinding derivative 64Cu-D-Cys-FBP8, detected the location of the 125I-labeled thrombus, confirming high target specificity. CONCLUSION: 68Ga-FBP14 and 111In-FBP15 have high fibrin affinity and thrombus specificity and represent useful PET and SPECT probes for thrombus detection.


Subject(s)
Fibrin/analogs & derivatives , Fibrin/metabolism , Gallium Radioisotopes , Indium Radioisotopes , Molecular Imaging/methods , Multimodal Imaging/methods , Radiopharmaceuticals , Thrombosis/diagnostic imaging , Animals , Gallium Radioisotopes/pharmacokinetics , Half-Life , Indium Radioisotopes/pharmacokinetics , Iodine Radioisotopes , Kidney/diagnostic imaging , Kidney/metabolism , Male , Models, Molecular , Positron-Emission Tomography , Radiopharmaceuticals/chemistry , Radiopharmaceuticals/metabolism , Radiopharmaceuticals/pharmacokinetics , Rats , Rats, Sprague-Dawley , Tissue Distribution , Tomography, Emission-Computed, Single-Photon
10.
J Hepatol ; 63(3): 689-96, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26022693

ABSTRACT

BACKGROUND & AIMS: Liver biopsy, the gold standard for assessing liver fibrosis, suffers from limitations due to sampling error and invasiveness. There is therefore a critical need for methods to non-invasively quantify fibrosis throughout the entire liver. The goal of this study was to use molecular Magnetic Resonance Imaging (MRI) of Type I collagen to non-invasively image liver fibrosis and assess response to rapamycin therapy. METHODS: Liver fibrosis was induced in rats by bile duct ligation (BDL). MRI was performed 4, 10, or 18 days following BDL. Some BDL rats were treated daily with rapamycin starting on day 4 and imaged on day 18. A three-dimensional (3D) inversion recovery MRI sequence was used to quantify the change in liver longitudinal relaxation rate (ΔR1) induced by the collagen-targeted probe EP-3533. Liver tissue was subjected to pathologic scoring of fibrosis and analyzed for Sirius Red staining and hydroxyproline content. RESULTS: ΔR1 increased significantly with time following BDL compared to controls in agreement with ex vivo measures of increasing fibrosis. Receiver operating characteristic curve analysis demonstrated the ability of ΔR1 to detect liver fibrosis and distinguish intermediate and late stages of fibrosis. EP-3533 MRI correctly characterized the response to rapamycin in 11 out of 12 treated rats compared to the standard of collagen proportional area (CPA). 3D MRI enabled characterization of disease heterogeneity throughout the whole liver. CONCLUSIONS: EP-3533 allowed for staging of liver fibrosis, assessment of response to rapamycin therapy, and demonstrated the ability to detect heterogeneity in liver fibrosis.


Subject(s)
Liver Cirrhosis, Experimental/pathology , Magnetic Resonance Imaging/methods , Sirolimus/therapeutic use , Animals , Bile Ducts , Disease Models, Animal , Elasticity Imaging Techniques , Ligation , Liver Cirrhosis, Experimental/drug therapy , Male , ROC Curve , Rats
11.
J Nucl Med ; 56(7): 1088-93, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25977464

ABSTRACT

UNLABELLED: The diagnosis of deep venous thromboembolic disease is still challenging despite the progress of current thrombus imaging modalities and new diagnostic algorithms. We recently reported the high target uptake and thrombus imaging efficacy of the novel fibrin-specific PET probe (64)Cu-FBP8. Here, we tested the feasibility of (64)Cu-FBP8 PET to detect source thrombi and culprit emboli after deep vein thrombosis and pulmonary embolism (DVT-PE). To support clinical translation of (64)Cu-FBP8, we performed a human dosimetry estimation using time-dependent biodistribution in rats. METHODS: Sprague-Dawley rats (n = 7) underwent ferric chloride application on the femoral vein to trigger thrombosis. Pulmonary embolism was induced 30 min or 2 d after DVT by intrajugular injection of a preformed blood clot labeled with (125)I-fibrinogen. PET imaging was performed to detect the clots, and SPECT was used to confirm in vivo the location of the pulmonary emboli. Ex vivo γ counting and histopathology were used to validate the imaging findings. Detailed biodistribution was performed in healthy rats (n = 30) at different time points after (64)Cu-FBP8 administration to estimate human radiation dosimetry. Longitudinal whole-body PET/MR imaging (n = 2) was performed after (64)Cu-FBP8 administration to further assess radioactivity clearance. RESULTS: (64)Cu-FBP8 PET imaging detected the location of lung emboli and venous thrombi after DVT-PE, revealing significant differences in uptake between target and background tissues (P < 0.001). In vivo SPECT imaging and ex vivo γ counting confirmed the location of the lung emboli. PET quantification of the venous thrombi revealed that probe uptake was greater in younger clots than in older ones, a result confirmed by ex vivo analyses (P < 0.001). Histopathology revealed an age-dependent reduction of thrombus fibrin content (P = 0.006), further supporting the imaging findings. Biodistribution and whole-body PET/MR imaging showed a rapid, primarily renal, body clearance of (64)Cu-FBP8. The effective dose was 0.021 mSv/MBq for males and 0.027 mSv/MBq for females, supporting the feasibility of using (64)Cu-FBP8 in human trials. CONCLUSION: We showed that (64)Cu-FBP8 PET is a feasible approach to image DVT-PE and that radiogenic adverse health effects should not limit the clinical translation of (64)Cu-FBP8.


Subject(s)
Copper Radioisotopes/chemistry , Fibrin/chemistry , Positron-Emission Tomography , Pulmonary Embolism/diagnostic imaging , Radiometry/methods , Venous Thrombosis/diagnostic imaging , Algorithms , Animals , Female , Male , Rats , Rats, Sprague-Dawley , Thrombosis/diagnostic imaging , Tissue Distribution , Tomography, Emission-Computed, Single-Photon , Whole Body Imaging
12.
Br J Nurs ; 24(6): 342-3, 2015.
Article in English | MEDLINE | ID: mdl-25815826
13.
Br J Nurs ; 23(18): 974-80, 2014.
Article in English | MEDLINE | ID: mdl-25302836

ABSTRACT

The delivery of compassionate care leads to safer care but this will only occur with an engaged workforce under effective leadership. In addition, there is a need to understand the behaviours that drive nurses to make particular decisions about care. This article describes the pilot of a simple survey tool (ENGAGE) to ascertain levels of staff engagement to use as an enabler of effective change. It also describes a unique pilot initiative of focus group work, quality improvements and leadership coaching on two hospital wards. This work centred on the patient-nurse relationship and challenged the traditional teaching of preventing harm. Initial results were promising: while many staff did not feel nurtured or guided by their manager or acknowledged by the senior team, they did feel glad to come to work and empowered to improve patient care. Three months after the first ENGAGE survey, a repeat found significantly improved levels of engagement. Alongside this were improvements in avoidable harms and patient experience. Staff were motivated to improve care and admitted they did not really see their patients as individuals with identity and personality. Managers were motivated to improve engagement and take their wards forward.


Subject(s)
Empathy , Nurse-Patient Relations , Risk Reduction Behavior , Humans , State Medicine , United Kingdom
14.
J Nucl Med ; 55(7): 1157-63, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24790217

ABSTRACT

UNLABELLED: Thrombus formation plays a major role in cardiovascular diseases, but noninvasive thrombus imaging is still challenging. Fibrin is a major component of both arterial and venous thrombi and represents an ideal candidate for imaging of thrombosis. Recently, we showed that (64)Cu-DOTA-labeled PET probes based on fibrin-specific peptides are suitable for thrombus imaging in vivo; however, the metabolic stability of these probes was limited. Here, we describe 4 new probes using either (64)Cu or aluminum fluoride (Al(18)F) chelated to 2 NOTA derivatives. METHODS: Probes were synthesized using a known fibrin-specific peptide conjugated to either NODAGA (FBP8, FBP10) or NOTA-monoamide (FBP9, FBP11) as chelators, followed by labeling with (64)Cu (FBP8 and FBP9) or Al(18)F (FBP10 and FBP11). PET imaging efficacy, pharmacokinetics, biodistribution, and metabolic stability were assessed in a rat model of arterial thrombosis. RESULTS: All probes had similar nanomolar affinity (435-760 nM) for the soluble fibrin fragment DD(E). PET imaging allowed clear visualization of thrombus by all probes, with a 5-fold or higher thrombus-to-background ratio. Compared with the previous DOTA derivative, the new (64)Cu probes FBP8 and FBP9 showed substantially improved metabolic stability (>85% intact in blood at 4 h after injection), resulting in high uptake at the target site (0.5-0.8 percentage injected dose per gram) that persisted over 5 h, producing increasingly greater target-to-background ratios. The thrombus uptake was 5- to 20-fold higher than the uptake in the contralateral artery, blood, muscle, lungs, bone, spleen, large intestine, and heart at 2 h after injection and 10- to 40-fold higher at 5 h. The Al(18)F derivatives FBP10 and FBP11 were less stable, in particular the NODAGA conjugate (FBP10, <30% intact in blood at 4 h after injection), which showed high bone uptake and low thrombus-to-background ratios that decreased over time. The high thrombus-to-contralateral ratios for all probes were confirmed by ex vivo biodistribution and autoradiography. The uptake in the liver (<0.5 percentage injected dose per gram), kidneys, and blood were similar for all tracers, and they all showed predominant renal clearance. CONCLUSION: FBP8, FBP9, and FBP11 showed excellent metabolic stability and high thrombus-to-background ratios and represent promising candidates for imaging of thrombosis in vivo.


Subject(s)
Chelating Agents/chemistry , Fibrin/metabolism , Peptides/chemistry , Positron-Emission Tomography/methods , Radioisotopes , Animals , Drug Stability , Heterocyclic Compounds/chemistry , Heterocyclic Compounds, 1-Ring , Male , Peptides/pharmacokinetics , Rats , Rats, Wistar , Thrombosis/diagnostic imaging
15.
Circ Cardiovasc Imaging ; 7(4): 697-705, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24777937

ABSTRACT

BACKGROUND: Fibrin is a major component of arterial and venous thrombi and represents an ideal candidate for molecular imaging of thrombosis. Here, we describe imaging properties and target uptake of a new fibrin-specific positron emission tomographic probe for thrombus detection and therapy monitoring in 2 rat thrombosis models. METHODS AND RESULTS: The fibrin-binding probe FBP7 was synthesized by conjugation of a known short cyclic peptide to a cross-bridged chelator (CB-TE2A), followed by labeling with copper-64. Adult male Wistar rats (n=26) underwent either carotid crush injury (mural thrombosis model) or embolic stroke (occlusive thrombosis model) followed by recombinant tissue-type plasminogen activator treatment (10 mg/kg, IV). FBP7 detected thrombus location in both animal models with a high positron emission tomographic target-to-background ratio that increased over time (>5-fold at 30-90 minutes, >15-fold at 240-285 minutes). In the carotid crush injury animals, biodistribution analysis confirmed high probe uptake in the thrombotic artery (≈0.5%ID/g; >5-fold greater than blood and other tissues of the head and thorax). Similar results were obtained from ex vivo autoradiography of the ipsilateral versus contralateral carotid arteries. In embolic stroke animals, positron emission tomographic-computed tomographic imaging localized the clot in the internal carotid/middle cerebral artery segment of all rats. Time-dependent reduction of activity at the level of the thrombus was detected in recombinant tissue-type plasminogen activator-treated rats but not in vehicle-injected animals. Brain autoradiography confirmed clot dissolution in recombinant tissue-type plasminogen activator-treated animals, but enduring high thrombus activity in control rats. CONCLUSIONS: We demonstrated that FBP7 is suitable for molecular imaging of thrombosis and thrombolysis in vivo and represents a promising candidate for bench-to-bedside translation.


Subject(s)
Carotid Artery Thrombosis/diagnosis , Fibrin , Intracranial Thrombosis/diagnosis , Molecular Imaging/methods , Positron-Emission Tomography/methods , Animals , Carotid Artery Thrombosis/metabolism , Carrier Proteins/pharmacokinetics , Disease Models, Animal , Fibrin/pharmacokinetics , Intracranial Thrombosis/metabolism , Male , Rats , Rats, Wistar , Reproducibility of Results , Tissue Distribution , Tomography, X-Ray Computed
16.
Mol Pharm ; 11(2): 617-29, 2014 Feb 03.
Article in English | MEDLINE | ID: mdl-24294970

ABSTRACT

In developing targeted probes for positron emission tomography (PET) based on (64)Cu, stable complexation of the radiometal is key, and a flexible handle for bioconjugation is highly advantageous. Here, we present the synthesis and characterization of the chelator pycup and four derivatives. Pycup is a cross-bridged cyclam derivative with a pyridyl donor atom integrated into the cross-bridge resulting in a pentadentate ligand. The pycup platform provides kinetic inertness toward (64)Cu dechelation and offers versatile bioconjugation chemistry. We varied the number and type of additional donor atoms by alkylation of the remaining two secondary amines, providing three model ligands, pycup2A, pycup1A1Bn, and pycup2Bn, in 3-4 synthetic steps from cyclam. All model copper complexes displayed very slow decomplexation in 5 M HCl and 90 °C (t1/2: 1.5 h for pycup1A1Bn, 2.7 h for pycup2A, 20.3 h for pycup2Bn). The single crystal crystal X-ray structure of the [Cu(pycup2Bn)](2+) complex showed that the copper was coordinated in a trigonal, bipyramidal manner. The corresponding radiochemical complexes were at least 94% stable in rat plasma after 24 h. Biodistribution studies conducted in Balb/c mice at 2 h postinjection of (64)Cu labeled pycup2A revealed low residual activity in kidney, liver, and blood pool with predominantly renal clearance observed. Pycup2A was readily conjugated to a fibrin-targeted peptide and labeled with (64)Cu for successful PET imaging of arterial thrombosis in a rat model, demonstrating the utility of our new chelator in vivo.


Subject(s)
Bridged-Ring Compounds/chemistry , Coordination Complexes/chemistry , Copper Radioisotopes/chemistry , Heterocyclic Compounds, 1-Ring/chemistry , Models, Molecular , Quantum Theory , Animals , Chelating Agents/chemistry , Crystallography, X-Ray , Drug Stability , Ligands , Male , Positron-Emission Tomography , Rats , Rats, Wistar
17.
J Dev Behav Pediatr ; 33(3): 236-43, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22278125

ABSTRACT

OBJECTIVE: We examined whether severity scores (1 SD vs 2 SDs) of a unique profile of the Child Behavior Checklist (CBCL) consisting of the Anxiety/Depression, Aggression, and Attention (AAA) scales would help differentiate levels of deficits in children with attention-deficit hyperactivity disorder (ADHD). STUDY DESIGN: Subjects were 197 children with ADHD and 224 without ADHD. We defined deficient emotional self-regulation (DESR) as an aggregate cutoff score of >180 but <210 (1 SD) on the AAA scales of the CBCL (CBCL-DESR) and Severe Dysregulation as an aggregate cutoff score of ≥210 on the same scales (CBCL-Severe Dysregulation). All subjects were assessed with structured diagnostic interviews and a range of functional measures. RESULTS: Thirty-six percent of children with ADHD had a positive CBCL-DESR profile versus 2% of controls (p < .001) and 19% had a positive CBCL-Severe Dysregulation profile versus 0% of controls (p < .001). The subjects positive for the CBCL-Severe Dysregulation profile differed selectively from those with the CBCL-DESR profile in having higher rates of unipolar and bipolar mood disorders, oppositional defiant and conduct disorders, psychiatric hospitalization at both baseline and follow-up assessments, and a higher rate of the CBCL-Severe Dysregulation in siblings. In contrast, the CBCL-DESR was associated with higher rates of comorbid disruptive behavior, anxiety disorders, and impaired interpersonal functioning compared with other ADHD children. CONCLUSION: Severity scores of the AAA CBCL profiles can help distinguish 2 groups of emotional regulation problems in children with ADHD.


Subject(s)
Attention Deficit Disorder with Hyperactivity/diagnosis , Psychiatric Status Rating Scales/standards , Adolescent , Adult , Aggression/psychology , Anxiety Disorders/diagnosis , Anxiety Disorders/epidemiology , Attention Deficit Disorder with Hyperactivity/classification , Attention Deficit Disorder with Hyperactivity/epidemiology , Case-Control Studies , Child , Depressive Disorder/diagnosis , Depressive Disorder/epidemiology , Female , Follow-Up Studies , Humans , Interpersonal Relations , Male , Parents/psychology , Sensitivity and Specificity , Severity of Illness Index , Siblings/psychology
19.
Paediatr Nurs ; 20(1): 30-3, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18335903

ABSTRACT

Following the successful implementation of High Dependency Care: a model for development at King's College hospital in 2005, the authors wished to consider the addition of a fourth tier to the model. A review of the clinical environment was undertaken and it was suggested that the introduction of an advanced nurse practitioner could contribute to the education and continuation of the outreach service detailed in the model, as well as to the improvement of critical care services and career development opportunities for nurses within the unit. A survey was undertaken to identify the views of medical and nursing staff about essential roles and responsibilities of advanced nurse practitioners in this area. This would then direct the development of a teaching and competency programme that could promote advanced practice in the critical care environment. There was no consensus on the tasks advanced nurse practitioners can undertake, the appropriate mentors in the clinical environment, the level of education they must achieve, nor the time in which this should be completed. There was confusion about the qualifications required for advanced nursing practice, mentorship and training. However, there was support for this role and respondents confirmed the view that advanced nursing practiced would be beneficial in patient care delivery.


Subject(s)
Attitude of Health Personnel , Critical Care/organization & administration , Nurse Clinicians/organization & administration , Nurse Practitioners/organization & administration , Nurse's Role , Pediatric Nursing/organization & administration , Career Mobility , Certification , Clinical Competence , Education, Nursing, Continuing/organization & administration , Education, Nursing, Graduate , Humans , Medical Staff, Hospital/psychology , Mentors , Models, Nursing , Nurse Clinicians/education , Nurse Practitioners/education , Nursing Methodology Research , Nursing Staff, Hospital/psychology , Pediatric Nursing/education , Preceptorship/organization & administration , Professional Autonomy , Surveys and Questionnaires , Total Quality Management/organization & administration
20.
Nurs Times ; 102(2): 26-7, 2006.
Article in English | MEDLINE | ID: mdl-16429685

ABSTRACT

Clinical complexity presents health professionals with a significant challenge if a patient with ALF is to survive. While efforts to develop pharmacological therapies and biomechanical techniques serve as a bridge to spontaneous recovery, liver transplantation is the most successful treatment for most cases.


Subject(s)
Liver Failure, Acute/physiopathology , Liver/physiology , Humans , Liver/physiopathology , Liver Failure, Acute/complications , Liver Failure, Acute/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...