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1.
Diabet Med ; 36(11): 1487-1493, 2019 11.
Article in English | MEDLINE | ID: mdl-31505060

ABSTRACT

AIM: Overweight and obesity are frequently reported in young persons with type 1 diabetes, however its relative magnitude in comparison to the general population is not well understood. This study compared the prevalence of overweight and obesity in young persons with type 1 diabetes to a reference population and explored possible associated factors, including gender, age, HbA1c , insulin regimen, age at diagnosis, diabetes duration, socio-economic status and cardiovascular disease risk factors. METHODS: A cross-sectional review was undertaken of data collected from youth (3-17 years) in 2016 and young adults (18-30 years) in 2015 with a diagnosis of type 1 diabetes for > 3 months attending diabetes centres in Newcastle, Australia. Rates of overweight and obesity were compared with matched population survey results. RESULTS: Data from 308 youth and 283 young adults were included. In girls, significantly higher prevalence of overweight and obesity were seen in the 5-8 (43% vs. 18%), 13-16 (41% vs. 27%), 18-24 (46% vs. 34%) and 25-30 (60% vs. 43%) years age groups; whereas in boys increased prevalence was observed in the 5-8 years age group only (41% vs. 18%). Rates of overweight and obesity increased with age across sexes. In youth, BMI standard deviation score was correlated with socio-economic status, insulin regimen, blood pressure and blood lipids (P < 0.05). In adults, BMI was positively associated with blood pressure, and longer diabetes duration (P < 0.02). CONCLUSIONS: Overweight and obesity are over-represented in young persons with type 1 diabetes, particularly girls. As overweight is associated with other cardiovascular disease markers early intervention is paramount.


Subject(s)
Diabetes Mellitus, Type 1/epidemiology , Diabetic Angiopathies/epidemiology , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Obesity/epidemiology , Overweight/epidemiology , Adolescent , Adult , Age Factors , Australia/epidemiology , Blood Pressure , Child , Child, Preschool , Cross-Sectional Studies , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/physiopathology , Diabetic Angiopathies/etiology , Diabetic Angiopathies/physiopathology , Female , Glycated Hemoglobin , Humans , Insulin/blood , Male , Obesity/complications , Obesity/physiopathology , Overweight/complications , Overweight/physiopathology , Patient Compliance , Prevalence , Sentinel Surveillance , Sex Factors , Socioeconomic Factors , Young Adult
2.
Diabet Med ; 36(2): 228-236, 2019 02.
Article in English | MEDLINE | ID: mdl-30443983

ABSTRACT

AIMS: Marked hyperglycaemia is common following betamethasone administration in women with gestational diabetes (GDM), and may contribute to neonatal hypoglycaemia. Validated protocols to deliver glycaemic stability following betamethasone are lacking. We hypothesized that an intravenous insulin (IVI) protocol for pregnancy-specific glycaemic targets (Pregnancy-IVI) would achieve greater at-target glycaemic control than a generic adult intravenous insulin protocol (Adult-IVI), and may reduce neonatal hypoglycaemia. METHODS: A retrospective cohort study of the performance Adult-IVI and Pregnancy-IVI following betamethasone in GDM, sequentially implemented at a tertiary hospital, without change in indication for IVI. Cases were identified by electronic record search. Primary outcome was percentage of on-IVI time with at-target glycaemia [blood glucose level (BGL) 3.8-7 mmol/l]. Secondary outcomes were time with critical hyperglycaemia (BGL > 10 mmol/l), occurrence of maternal hypoglycaemia (BGL < 3.8 mmol/l), and incidence of neonatal hypoglycaemia (BGL ≤ 2.5 mmol/l) if betamethasone was administered within 48 h of birth. RESULTS: The cohorts comprised 151 women (Adult-IVI n = 86; Pregnancy-IVI n = 65). The primary outcome was 68% time-at-target [95% confidence interval (CI) 64-71%) for Pregnancy-IVI compared with 55% (95% CI 50-60%) for Adult-IVI (P = 0.0002). Critical maternal hyperglycaemia (0% vs. 2%, P = 0.02) and hypoglycaemia (2% vs. 12%, P = 0.02) were both lower with Pregnancy-IVI than Adult-IVI. Neonatal hypoglycaemia was less common after Pregnancy-IVI (29%) than after Adult-IVI (54%, P = 0.03). A multiple logistic regression model adjusting for potential confounders gave an odds ratio for neonatal hypoglycaemia with Pregnancy-IVI of 0.27 (95% CI 0.10-0.76, P = 0.01). CONCLUSIONS: An IVI protocol designed for pregnancy effectively controlled maternal hyperglycaemia following betamethasone administration in GDM. This is the first intervention to show a reduction in betamethasone-associated neonatal hypoglycaemia, linked with optimum maternal glycaemic control.


Subject(s)
Betamethasone/adverse effects , Diabetes, Gestational/drug therapy , Glucocorticoids/adverse effects , Hypoglycemia/prevention & control , Hypoglycemic Agents/administration & dosage , Insulin/administration & dosage , Adult , Betamethasone/administration & dosage , Blood Glucose/drug effects , Clinical Protocols , Diabetes, Gestational/blood , Female , Glucocorticoids/administration & dosage , Humans , Hyperglycemia/chemically induced , Infant, Newborn , Infusions, Intravenous , Pregnancy , Retrospective Studies , Treatment Outcome
3.
Sci Rep ; 7(1): 7642, 2017 08 09.
Article in English | MEDLINE | ID: mdl-28794469

ABSTRACT

Deletion of phenylalanine 508 of the cystic fibrosis transmembrane conductance regulator (ΔF508 CFTR) is a major cause of cystic fibrosis (CF), one of the most common inherited childhood diseases. ΔF508 CFTR is a trafficking mutant that is retained in the endoplasmic reticulum (ER) and unable to reach the plasma membrane. Efforts to enhance exit of ΔF508 CFTR from the ER and improve its trafficking are of utmost importance for the development of treatment strategies. Using protein interaction profiling and global bioinformatics analysis we revealed mammalian target of rapamycin (mTOR) signalling components to be associated with ∆F508 CFTR. Our results demonstrated upregulated mTOR activity in ΔF508 CF bronchial epithelial (CFBE41o-) cells. Inhibition of the Phosphatidylinositol 3-kinase/Akt/Mammalian Target of Rapamycin (PI3K/Akt/mTOR) pathway with 6 different inhibitors demonstrated an increase in CFTR stability and expression. Mechanistically, we discovered the most effective inhibitor, MK-2206 exerted a rescue effect by restoring autophagy in ΔF508 CFBE41o- cells. We identified Bcl-2-associated athanogene 3 (BAG3), a regulator of autophagy and aggresome clearance to be a potential mechanistic target of MK-2206. These data further link the CFTR defect to autophagy deficiency and demonstrate the potential of the PI3K/Akt/mTOR pathway for therapeutic targeting in CF.


Subject(s)
Cystic Fibrosis/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects , TOR Serine-Threonine Kinases/metabolism , Cell Line , Chromatography, Liquid , Computational Biology/methods , Cystic Fibrosis/drug therapy , Cystic Fibrosis/genetics , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Gene Ontology , Humans , Mass Spectrometry , Mechanistic Target of Rapamycin Complex 1/metabolism , Mechanistic Target of Rapamycin Complex 2/metabolism , Models, Biological , Multiprotein Complexes/metabolism , Neoplasm Staging , Protein Binding , Protein Interaction Mapping , Protein Interaction Maps , RNA, Small Interfering/genetics
4.
Diabetes Res Clin Pract ; 131: 154-160, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28750218

ABSTRACT

AIMS: To assess the relationship between insulin resistance (IR), retinopathy and maculopathy in young adults with Type 1 diabetes mellitus. METHODS: A cross-sectional study at a regional Australian tertiary hospital. Retinal pathology, assessed by colour fundus photography, was correlated with two surrogate measures of IR: estimated Glucose Disposal Rate (eGDR) and Insulin Sensitivity Score (ISS), where lower scores reflect greater IR. RESULTS: 107 patients were recruited, with mean age 24.7years, 53% male, and mean duration of disease 10.8years. Mean eGDR scores (5.6vs 8.0 p<0.001) and ISS (4.7vs 7.9, p<0.001) were lower in subjects having at least moderate non-proliferative diabetic retinopathy (NPDR; relative to nil/mild-NPDR). Similarly, mean eGDR (4.2vs 6.2, p=0.001) and ISS (3.8vs 6.1, p=0.003) were lower in patients with maculopathy. Multivariate logistic regression modelling was used to control for confounding. For retinopathy severity, a unit increase in eGDR or ISS (representing lower IR) was associated with a 50% decrease in odds of moderate-NPDR or worse (eGDR OR 0.5, 95%CI 0.32-0.77, p=0.002; ISS OR 0.49, 95%CI 0.29-0.84, p=0.01). A unit increase in eGDR or ISS was associated with a 46-56% decrease in odds of maculopathy (eGDR OR 0.54, 95%CI 0.37-0.81, p=0.003; ISS OR 0.44, 95%CI 0.22-0.88, p=0.02). CONCLUSIONS: IR correlates with more severe retinopathy in young adults with Type 1DM. This is the first description of a correlation between IR and maculopathy in Type 1DM, warranting further evaluation. Prospective studies examining whether reducing IR can improve microvascular complications are required.


Subject(s)
Diabetes Mellitus, Type 1/complications , Diabetic Retinopathy/etiology , Glucose/metabolism , Macular Degeneration/etiology , Adolescent , Adult , Cross-Sectional Studies , Diabetic Retinopathy/metabolism , Female , Humans , Insulin Resistance , Macular Degeneration/metabolism , Male , Prospective Studies , Young Adult
5.
Diabet Med ; 34(5): 725-731, 2017 05.
Article in English | MEDLINE | ID: mdl-28199038

ABSTRACT

AIM: There is a high incidence of neonatal hypoglycaemia in neonates born to mothers with pre-existing diabetes. This often necessitates admission to the neonatal intensive care. Guidelines suggest maintaining intrapartum blood glucose levels (BGLs) of 4-7 mmol/l in women with diabetes to reduce the risk of neonatal hypoglycaemia. This study assessed whether intrapartum BGLs in women with pre-gestational Type 1 and 2 diabetes were predictive of neonatal hypoglycaemia. METHODS: A retrospective analysis of 261 births delivered at a tertiary hospital in Australia from 2009 to 2014. RESULTS: There were 122 cases of neonatal hypoglycaemia (glucose ≤ 2.6 mmol/l) in 261 births (47%). The mothers in the neonatal hypoglycaemia group spent less time with BGL in the range 4-7 mmol/l [55 ± 37% vs. 65 ± 35%, P = 0.02; odds ratio (OR) 0.992, P = 0.03] and more time with BGL in the 7-10 mmol/l range (31 ± 34% vs. 18 ± 27%, P = 0.003; OR 1.013, P = 0.003) compared with those without neonatal hypoglycaemia. Although statistically significant, receiver operating characteristic (ROC) curve analysis showed that time spent with maternal BGLs in the range 4-7 mmol/l [area under the curve (AUC) = 0.58] or 7-10 mmol (AUC = 0.60) was not strong enough to be a useful clinical predictor of neonatal hypoglycaemia. HbA1c in the second trimester of pregnancy (P = 0.02, OR 1.42) and percentage time spent in BGL range of 7-10 mmol/l (P = 0.001, OR 1.02) were both associated with a risk of neonatal hypoglycaemia in a logistic regression model. HbA1c in the third trimester (P = 0.07, OR 1.28) approached, but did not reach, significance. CONCLUSIONS: These data support a BGL range of 4-7 mmol/l as an intrapartum target. Glycaemic control in the second trimester is associated with neonatal hypoglycaemia. Improvement in ante- and intrapartum glycaemic control may reduce neonatal hypoglycaemia in women with pre-existing diabetes.


Subject(s)
Blood Glucose/metabolism , Hyperglycemia/complications , Hypoglycemia/congenital , Hypoglycemia/diagnosis , Infant, Newborn, Diseases/diagnosis , Parturition/blood , Pregnancy in Diabetics/blood , Adult , Australia , Blood Glucose/analysis , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/diagnosis , Female , Humans , Hyperglycemia/blood , Hypoglycemia/blood , Infant, Newborn , Infant, Newborn, Diseases/blood , Pregnancy , Pregnancy Complications/blood , Pregnancy Complications/diagnosis , Pregnancy in Diabetics/diagnosis , Prognosis , Retrospective Studies , Time Factors , Young Adult
6.
Transl Psychiatry ; 6(11): e959, 2016 11 29.
Article in English | MEDLINE | ID: mdl-27898073

ABSTRACT

The postsynaptic density (PSD) contains a complex set of proteins of known relevance to neuropsychiatric disorders such as schizophrenia and bipolar disorder. We enriched for this anatomical structure in the anterior cingulate cortex of 16 bipolar disorder samples and 20 controls from the Stanley Medical Research Institute. Unbiased shotgun proteomics incorporating label-free quantitation was used to identify differentially expressed proteins. Quantitative investigation of the PSD identified 2033 proteins, among which 288 were found to be differentially expressed. Validation of expression changes of DNM1, DTNA, NDUFV2, SEPT11 and SSBP was performed by western blotting. Bioinformatics analysis of the differentially expressed proteins implicated metabolic pathways including mitochondrial function, the tricarboxylic acid cycle, oxidative phosphorylation, protein translation and calcium signaling. The data implicate PSD-associated proteins, and specifically mitochondrial function in bipolar disorder. They relate synaptic function in bipolar disorder and the energy pathways that underpin it. Overall, our findings add to a growing literature linking the PSD and mitochondrial function in psychiatric disorders generally, and suggest that mitochondrial function associated with the PSD is particularly important in bipolar disorder.


Subject(s)
Bipolar Disorder/physiopathology , Energy Metabolism/physiology , Gyrus Cinguli/physiopathology , Post-Synaptic Density/physiology , Proteomics , Synaptic Transmission/physiology , Adult , Blotting, Western , Female , Humans , Male , Mass Spectrometry , Middle Aged , Mitochondria/physiology , Mitochondrial Diseases/physiopathology , Reference Values , Schizophrenia/physiopathology
7.
J Addict Res Ther ; 7(4)2016 08.
Article in English | MEDLINE | ID: mdl-28078167

ABSTRACT

The rate of Neonatal Abstinence Syndrome (NAS) has drastically increased over the past decade. The average hospital expense per NAS patient has tripled, while the number of babies born to opioid-dependent mothers has increased to 5 in 1000 births. Current treatment options are limited to opioid replacement and tapering. Consequently, we examined the efficacy of prenatal, low-dose and short-term vigabatrin (γ-vinyl GABA, GVG) exposure for attenuating these symptoms as well as the metabolic changes observed in the brains of these animals upon reaching adolescence. Pregnant Sprague-Dawley rats were treated in one of four ways: 1) saline; 2) morphine alone; 3) morphine+GVG at 25 mg/kg; 4) morphine+GVG at 50 mg/kg. Morphine was administered throughout gestation, while GVG administration occurred only during the last 5 days of gestation. On post-natal day 1, naloxone-induced withdrawal behaviours were recorded in order to obtain a gross behaviour score. Approximately 28 days following birth, 18FDG microPET scans were obtained on these same animals (Groups 1, 2, and 4). Morphine-treated neonates demonstrated significantly higher withdrawal scores than saline controls. However, GVG at 50 but not 25 mg/kg/day significantly attenuated them. Upon reaching adolescence, morphine treated animals showed regionally specific changes in 18FDG uptake. Again, prenatal GVG exposure blocked them. These data demonstrate that low-dose, short-term prenatal GVG administration blocks naloxone-induced withdrawal in neonates. Taken together, these preliminary findings suggest that GVG may provide an alternative and long-lasting pharmacologic approach for the management of neonatal and adolescent symptoms associated with NAS.

8.
Transl Psychiatry ; 5: e663, 2015 Oct 20.
Article in English | MEDLINE | ID: mdl-26485547

ABSTRACT

Human olfactory neurosphere-derived (ONS) cells have the potential to provide novel insights into the cellular pathology of schizophrenia. We used discovery-based proteomics and targeted functional analyses to reveal reductions in 17 ribosomal proteins, with an 18% decrease in the total ribosomal signal intensity in schizophrenia-patient-derived ONS cells. We quantified the rates of global protein synthesis in vitro and found a significant reduction in the rate of protein synthesis in schizophrenia patient-derived ONS cells compared with control-derived cells. Protein synthesis rates in fibroblast cell lines from the same patients did not differ, suggesting cell type-specific effects. Pathway analysis of dysregulated proteomic and transcriptomic data sets from these ONS cells converged to highlight perturbation of the eIF2α, eIF4 and mammalian target of rapamycin (mTOR) translational control pathways, and these pathways were also implicated in an independent induced pluripotent stem cell-derived neural stem model, and cohort, of schizophrenia patients. Analysis in schizophrenia genome-wide association data from the Psychiatric Genetics Consortium specifically implicated eIF2α regulatory kinase EIF2AK2, and confirmed the importance of the eIF2α, eIF4 and mTOR translational control pathways at the level of the genome. Thus, we integrated data from proteomic, transcriptomic, and functional assays from schizophrenia patient-derived ONS cells with genomics data to implicate dysregulated protein synthesis for the first time in schizophrenia.


Subject(s)
Olfactory Mucosa/metabolism , Protein Biosynthesis/physiology , Schizophrenia/metabolism , Adolescent , Adult , Cells, Cultured , Female , Humans , In Vitro Techniques , Male , Middle Aged , Proteomics , Signal Transduction/physiology , Young Adult
9.
Mol Psychiatry ; 20(4): 424-32, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25048004

ABSTRACT

The postsynaptic density (PSD) contains a complex set of proteins of known relevance to neuropsychiatric disorders, and schizophrenia specifically. We enriched for this anatomical structure, in the anterior cingulate cortex, of 20 schizophrenia samples and 20 controls from the Stanley Medical Research Institute, and used unbiased shotgun proteomics incorporating label-free quantitation to identify differentially expressed proteins. Quantitative investigation of the PSD revealed more than 700 protein identifications and 143 differentially expressed proteins. Prominent among these were altered expression of proteins involved in clathrin-mediated endocytosis (CME) (Dynamin-1, adaptor protein 2) and N-methyl-D-aspartate (NMDA)-interacting proteins such as CYFIP2, SYNPO, SHANK3, ESYT and MAPK3 (all P<0.0015). Pathway analysis of the differentially expressed proteins implicated the cellular processes of endocytosis, long-term potentiation and calcium signaling. Both single-gene and gene-set enrichment analyses in genome-wide association data from the largest schizophrenia sample to date of 13,689 cases and 18,226 controls show significant association of HIST1H1E and MAPK3, and enrichment of our PSD proteome. Taken together, our data provide robust evidence implicating PSD-associated proteins and genes in schizophrenia, and suggest that within the PSD, NMDA-interacting and endocytosis-related proteins contribute to disease pathophysiology.


Subject(s)
Gene Expression Regulation/genetics , Genomics , Gyrus Cinguli/pathology , Post-Synaptic Density , Proteomics , Schizophrenia , Animals , Antipsychotic Agents/pharmacology , Endocytosis/drug effects , Endocytosis/physiology , Female , Genetic Association Studies , Gyrus Cinguli/drug effects , Gyrus Cinguli/metabolism , Haloperidol/pharmacology , Humans , Male , N-Methylaspartate/genetics , N-Methylaspartate/metabolism , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Post-Synaptic Density/genetics , Post-Synaptic Density/metabolism , Post-Synaptic Density/pathology , Rats , Reproducibility of Results , Schizophrenia/genetics , Schizophrenia/metabolism , Schizophrenia/pathology , Signal Transduction/drug effects , Signal Transduction/physiology , Synaptotagmins/metabolism , Tandem Mass Spectrometry
10.
J Cereb Blood Flow Metab ; 34(8): 1315-20, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24824914

ABSTRACT

Systemic lupus erythematosus (SLE) is characterized by multiorgan inflammation, neuropsychiatric disorders (NPSLE), and anti-nuclear antibodies. We previously identified a subset of anti-DNA antibodies (DNRAb) cross-reactive with the N-methyl-D-aspartate receptor, present in 30% to 40% of patients, able to enhance excitatory post-synaptic potentials and trigger neuronal apoptosis. DNRAb+ mice exhibit memory impairment or altered fear response, depending on whether the antibody penetrates the hippocampus or amygdala. Here, we used 18F-fluorodeoxyglucose (FDG) microPET to plot changes in brain metabolism after regional blood-brain barrier (BBB) breach. In DNRAb+ mice, metabolism declined at the site of BBB breach in the first 2 weeks and increased over the next 2 weeks. In contrast, DNRAb- mice exhibited metabolic increases in these regions over the 4 weeks after the insult. Memory impairment was present in DNRAb+ animals with hippocampal BBB breach and altered fear conditioning in DNRAb+ mice with amygdala BBB breach. In DNRAb+ mice, we observed an inverse relationship between neuron number and regional metabolism, while a positive correlation was observed in DNRAb- mice. These findings suggest that local metabolic alterations in this model take place through different mechanisms with distinct time courses, with important implications for the interpretation of imaging data in SLE subjects.


Subject(s)
Amygdala/metabolism , Antibodies, Antinuclear/metabolism , Blood-Brain Barrier/metabolism , Hippocampus/metabolism , Lupus Erythematosus, Systemic/metabolism , Amygdala/diagnostic imaging , Amygdala/pathology , Animals , Behavior, Animal , Blood-Brain Barrier/diagnostic imaging , Blood-Brain Barrier/pathology , Disease Models, Animal , Female , Fluorodeoxyglucose F18 , Hippocampus/diagnostic imaging , Hippocampus/pathology , Lupus Erythematosus, Systemic/diagnostic imaging , Lupus Erythematosus, Systemic/pathology , Lupus Erythematosus, Systemic/psychology , Mice , Mice, Inbred BALB C , Neurons/metabolism , Neurons/pathology , Positron-Emission Tomography
12.
Curr Top Behav Neurosci ; 11: 93-115, 2012.
Article in English | MEDLINE | ID: mdl-22411423

ABSTRACT

Behavioral neuroimaging is a rapidly evolving discipline that represents a marriage between the fields of behavioral neuroscience and preclinical molecular imaging. This union highlights the changing role of imaging in translational research. Techniques developed for humans are now widely applied in the study of animal models of brain disorders such as drug addiction. Small animal or preclinical imaging allows us to interrogate core features of addiction from both behavioral and biological endpoints. Snapshots of brain activity allow us to better understand changes in brain function and behavior associated with initial drug exposure, the emergence of drug escalation, and repeated bouts of drug withdrawal and relapse. Here we review the development and validation of new behavioral imaging paradigms and several clinically relevant radiotracers used to capture dynamic molecular events in behaving animals. We will discuss ways in which behavioral imaging protocols can be optimized to increase throughput and quantitative methods. Finally, we discuss our experience with the practical aspects of behavioral neuroimaging, so investigators can utilize effective animal models to better understand the addicted brain and behavior.


Subject(s)
Brain/pathology , Disease Models, Animal , Neuroimaging , Substance-Related Disorders , Animals , Brain/diagnostic imaging , Brain/drug effects , Dopamine/metabolism , Fluorodeoxyglucose F18/pharmacokinetics , Humans , Raclopride/pharmacokinetics , Radionuclide Imaging , Substance-Related Disorders/diagnostic imaging , Substance-Related Disorders/pathology , Substance-Related Disorders/physiopathology
13.
FEBS J ; 279(5): 871-81, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22240000

ABSTRACT

There is increasing evidence that hyperoxia, particularly at the time of birth, may result in neurological injury, in particular to the susceptible vasculature of these tissues. This study was aimed at determining whether overexpression of extracellular superoxide dismutase (EC-SOD) is protective against brain injury induced by hyperoxia. Transgenic (TG) mice (with an extra copy of the human extracellular superoxide dismutase gene) and wild-type (WT) neonate mice were exposed to hyperoxia (95% of F(i) o(2) ) for 7 days after birth versus the control group in room air. Brain positron emission tomography (PET) scanning with fludeoxyglucose (FDG) isotope uptake was performed after exposure. To assess apoptosis induced by hyperoxia exposure, caspase 3 ELISA and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining were performed. Quantitative western blot for the following inflammatory markers was performed: glial fibrillary acidic protein, ionized calcium-binding adaptor molecule 1, macrophage-inhibiting factor, and phospho-AMP-activated protein kinase. PET scanning with FDG isotope uptake showed significantly higher uptake in the WT hyperoxia neonate brain group (0.14 ± 0.03) than in both the TG group (0.09 ± 0.01) and the control group (0.08 ± 0.02) (P< 0.05). Histopathological investigation showed more apoptosis and dead neurons in hippocampus and cerebellum brain sections of WT neonate mice after exposure to hyperoxia than in TG mice; this finding was also confirmed by TUNEL staining. The caspase 3 assay confirmed the finding of more apoptosis in WT hyperoxia neonates (0.814 ± 0.112) than in the TG hyperoxic group (0.579 ± 0.144) (P < 0.05); this finding was also confirmed by TUNEL staining. Quantitative western blotting for the inflammatory and metabolic markers showed significantly higher expression in the WT group than in the TG and control groups. Thus, overexpression of EC-SOD in the neonate brain offers significant protection against hyperoxia-induced brain damage.


Subject(s)
Brain Injuries/enzymology , Brain Injuries/prevention & control , Hyperoxia/complications , Superoxide Dismutase/metabolism , Animals , Animals, Newborn , Apoptosis , Biomarkers/metabolism , Blotting, Western , Brain Injuries/etiology , Enzyme-Linked Immunosorbent Assay , Humans , Hyperoxia/pathology , In Situ Nick-End Labeling , Mice , Mice, Inbred C57BL , Mice, Transgenic , Oxidative Stress , Positron-Emission Tomography , Superoxide Dismutase/genetics
14.
Neuroimage ; 59(3): 2689-99, 2012 Feb 01.
Article in English | MEDLINE | ID: mdl-21767654

ABSTRACT

The parametric ntPET model (p-ntPET) estimates the kinetics of neurotransmitter release from dynamic PET data with receptor-ligand radiotracers. Here we introduce a linearization (lp-ntPET) that is computationally efficient and can be applied to single scan data. lp-ntPET employs a non-invasive reference region input function and extends the LSRRM of Alpert et al. (2003) using basis functions to characterize the time course of neurotransmitter activation. In simulation studies, the temporal precision of neurotransmitter profiles estimated by lp-ntPET was similar to that of p-ntPET (standard deviation ~3 min for responses early in the scan) while computation time was reduced by several orders of magnitude. Violations of model assumptions such as activation-induced changes in regional blood flow or specific binding in the reference tissue have negligible effects on lp-ntPET performance. Application of the lp-ntPET method is demonstrated on [11C]raclopride data acquired in rats receiving methamphetamine, which yielded estimated response functions that were in good agreement with simultaneous microdialysis measurements of extracellular dopamine concentration. These results demonstrate that lp-ntPET is a computationally efficient, linear variant of ntPET that can be applied to PET data from single or multiple scan designs to estimate the time course of neurotransmitter activation.


Subject(s)
Image Processing, Computer-Assisted/methods , Neurotransmitter Agents/physiology , Positron-Emission Tomography/methods , Positron-Emission Tomography/statistics & numerical data , Algorithms , Animals , Computer Simulation , Dopamine/metabolism , Dopamine Antagonists , Extracellular Space/drug effects , Extracellular Space/metabolism , Linear Models , Microdialysis , Models, Neurological , Models, Statistical , Raclopride , Radiopharmaceuticals , Rats
15.
J Med Chem ; 55(1): 357-66, 2012 Jan 12.
Article in English | MEDLINE | ID: mdl-22128851

ABSTRACT

Vigabatrin, a GABA aminotransferase (GABA-AT) inactivator, is used to treat infantile spasms and refractory complex partial seizures and is in clinical trials to treat addiction. We evaluated a novel GABA-AT inactivator (1S, 3S)-3-amino-4-difluoromethylenyl-1-cyclopentanoic acid (CPP-115, compound 1) and observed that it does not exhibit other GABAergic or off-target activities and is rapidly and completely orally absorbed and eliminated. By use of in vivo microdialysis techniques in freely moving rats and microPET imaging techniques, 1 produced similar inhibition of cocaine-induced increases in extracellular dopamine and in synaptic dopamine in the nucleus accumbens at (1)/(300) to (1)/(600) the dose of vigabatrin. It also blocks expression of cocaine-induced conditioned place preference at a dose (1)/(300) that of vigabatrin. Electroretinographic (ERG) responses in rats treated with 1, at doses 20-40 times higher than those needed to treat addiction in rats, exhibited reductions in ERG responses, which were less than the reductions observed in rats treated with vigabatrin at the same dose needed to treat addiction in rats. In conclusion, 1 can be administered at significantly lower doses than vigabatrin, which suggests a potential new treatment for addiction with a significantly reduced risk of visual field defects.


Subject(s)
4-Aminobutyrate Transaminase/metabolism , Carboxylic Acids/chemical synthesis , Cocaine-Related Disorders/drug therapy , Cyclopentanes/chemical synthesis , Animals , Biological Availability , Carboxylic Acids/pharmacology , Carboxylic Acids/toxicity , Cocaine-Related Disorders/metabolism , Cocaine-Related Disorders/psychology , Cyclopentanes/pharmacology , Cyclopentanes/toxicity , Dogs , Dopamine/metabolism , Electroretinography , Female , GABA Plasma Membrane Transport Proteins/physiology , GABA Uptake Inhibitors/chemical synthesis , GABA Uptake Inhibitors/pharmacology , GABA Uptake Inhibitors/toxicity , Humans , Male , Mice , Microdialysis , Nucleus Accumbens/drug effects , Nucleus Accumbens/metabolism , Oocytes/drug effects , Oocytes/physiology , Positron-Emission Tomography , Proline/analogs & derivatives , Radioligand Assay , Rats , Rats, Sprague-Dawley , Rats, Wistar , Receptors, GABA/metabolism , Retina/drug effects , Retina/physiology , Stereoisomerism , Tissue Distribution , Vigabatrin/pharmacology , Xenopus laevis
16.
Proc Natl Acad Sci U S A ; 108(16): 6638-43, 2011 Apr 19.
Article in English | MEDLINE | ID: mdl-21464304

ABSTRACT

The factors that determine symptom penetrance in inherited disease are poorly understood. Increasingly, magnetic resonance diffusion tensor imaging (DTI) and PET are used to separate alterations in brain structure and function that are linked to disease symptomatology from those linked to gene carrier status. One example is DYT1 dystonia, a dominantly inherited movement disorder characterized by sustained muscle contractions, postures, and/or involuntary movements. This form of dystonia is caused by a 3-bp deletion (i.e., ΔE) in the TOR1A gene that encodes torsinA. Carriers of the DYT1 dystonia mutation, even if clinically nonpenetrant, exhibit abnormalities in cerebellothalamocortical (CbTC) motor pathways. However, observations in human gene carriers may be confounded by variability in genetic background and age. To address this problem, we implemented a unique multimodal imaging strategy in a congenic line of DYT1 mutant mice that contain the ΔE mutation in the endogenous mouse torsinA allele (i.e., DYT1 knock-in). Heterozygous knock-in mice and littermate controls underwent microPET followed by ex vivo high-field DTI and tractographic analysis. Mutant mice, which do not display abnormal movements, exhibited significant CbTC tract changes as well as abnormalities in brainstem regions linking cerebellar and basal ganglia motor circuits highly similar to those identified in human nonmanifesting gene carriers. Moreover, metabolic activity in the sensorimotor cortex of these animals was closely correlated with individual measures of CbTC pathway integrity. These findings further link a selective brain circuit abnormality to gene carrier status and demonstrate that DYT1 mutant torsinA has similar effects in mice and humans.


Subject(s)
Brain , Dystonia , Efferent Pathways , Genetic Diseases, Inborn , Molecular Chaperones/metabolism , Movement Disorders , Alleles , Animals , Base Sequence , Brain/abnormalities , Brain/metabolism , Dystonia/genetics , Dystonia/metabolism , Dystonia/pathology , Efferent Pathways/abnormalities , Efferent Pathways/metabolism , Gene Knock-In Techniques , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/metabolism , Genetic Diseases, Inborn/pathology , Humans , Mice , Mice, Transgenic , Molecular Chaperones/genetics , Movement Disorders/genetics , Movement Disorders/metabolism , Movement Disorders/pathology , Sequence Deletion
17.
Nature ; 470(7335): 510-2, 2011 Feb 24.
Article in English | MEDLINE | ID: mdl-21326201

ABSTRACT

The extragalactic background light at far-infrared wavelengths comes from optically faint, dusty, star-forming galaxies in the Universe with star formation rates of a few hundred solar masses per year. These faint, submillimetre galaxies are challenging to study individually because of the relatively poor spatial resolution of far-infrared telescopes. Instead, their average properties can be studied using statistics such as the angular power spectrum of the background intensity variations. A previous attempt at measuring this power spectrum resulted in the suggestion that the clustering amplitude is below the level computed with a simple ansatz based on a halo model. Here we report excess clustering over the linear prediction at arcminute angular scales in the power spectrum of brightness fluctuations at 250, 350 and 500 µm. From this excess, we find that submillimetre galaxies are located in dark matter haloes with a minimum mass, M(min), such that log(10)[M(min)/M(⊙)] = 11.5(+0.7)(-0.2) at 350 µm, where M(⊙) is the solar mass. This minimum dark matter halo mass corresponds to the most efficient mass scale for star formation in the Universe, and is lower than that predicted by semi-analytical models for galaxy formation.

19.
Hernia ; 15(6): 695-8, 2011 Dec.
Article in English | MEDLINE | ID: mdl-20694799

ABSTRACT

Laparoscopic Nissen fundoplication is the treatment of choice for medically refractive gastro-oesophageal reflux disease as it is considered safe, cost efficient and effective. Unusual variants of internal abdominal herniation, however, have been reported after the procedure. Here, we present a case of a 38-year-old woman who presented 3 months after a successful laparoscopic Nissen Rossetti fundoplication, with abdominal pain and persistent vomiting. Abdominal X-ray at the time of admission was normal but CT suggested internal herniation of the stomach. Laparoscopy confirmed internal herniation of the anterior wall of the stomach through an attenuated fundoplication wrap. We show that a prompt diagnosis of this complication, which we have not found reported previously in the English literature, can be achieved by CT, permitting an early laparoscopic intervention to preserve the viability of the obstructed segment of stomach.


Subject(s)
Fundoplication/adverse effects , Hernia/etiology , Stomach Diseases/etiology , Adult , Female , Gastroesophageal Reflux/surgery , Herniorrhaphy , Humans , Laparoscopy , Radiography , Stomach Diseases/diagnostic imaging , Stomach Diseases/surgery
20.
Eur J Neurosci ; 30(8): 1565-75, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19821842

ABSTRACT

Most studies of the effect of cocaine on brain activity in laboratory animals are preformed under anesthesia, which could potentially affect the physiological responses to cocaine. Here we assessed the effects of two commonly used anesthetics [alpha-chloralose (alpha-CHLOR) and isofluorane (ISO)] on the effects of acute cocaine (1 mg/kg i.v.) on cerebral blood flow (CBF), cerebral blood volume (CBV), and tissue hemoglobin oxygenation (S(t)O(2)) using optical techniques and cocaine's pharmacokinetics (PK) and binding in the rat brain using (PET) and [(11)C]cocaine. We showed that acute cocaine at a dose abused by cocaine abusers decreased CBF, CBV and S(t)O(2) in rats anesthetized with ISO, whereas it increased these parameters in rats anesthetized with alpha-CHLOR. Importantly, in ISO-anesthetized animals cocaine-induced changes in CBF and S(t)O(2) were coupled, whereas for alpha-CHLOR these measures were uncoupled. Moreover, the clearance of [(11)C]cocaine from the brain was faster for ISO (peak half-clearance 15.8 +/- 2.8 min) than for alpha-CHLOR (27.5 +/- 0.6 min), and the ratio of specific to non-specific binding of [(11)C]cocaine in the brain was higher for ISO- (3.37 +/- 0.32) than for alpha-CHLOR-anesthetized rats (2.24 +/- 0.4). For both anesthetics, cocaine-induced changes in CBF followed the fast uptake of [(11)C]cocaine in the brain (peaking at approximately 2.5-4 min), but only for ISO did the duration of the CBV and S(t)O(2) changes correspond to the rate of [(11)C]cocaine's clearance from the brain. These results demonstrate that anesthetics influence cocaine's hemodynamic and metabolic changes in the brain, and its binding and PK, which highlights the need to better understand the interactions between anesthetics and pharmacological challenges in brain functional imaging studies.


Subject(s)
Anesthetics/pharmacology , Brain/drug effects , Chloralose/pharmacology , Cocaine/pharmacokinetics , Isoflurane/pharmacology , Animals , Blood Pressure/drug effects , Blood Volume/drug effects , Brain/diagnostic imaging , Brain/metabolism , Brain Mapping/methods , Carbon Isotopes/pharmacokinetics , Cerebrovascular Circulation/drug effects , Electrocardiography/methods , Female , Heart Rate/drug effects , Oxyhemoglobins/metabolism , Positron-Emission Tomography/methods , Rats , Rats, Sprague-Dawley , Time Factors
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