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1.
Gynecol Oncol Rep ; 37: 100808, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34169134

ABSTRACT

The role for localized radiation to treat ovarian cancer (OC) patients with locally recurrent vaginal/perirectal lesions remains unclear, though we hypothesize these patients may be salvaged locally and gain long-term survival benefit. We describe our institutional outcomes using intensity modulated radiation therapy (IMRT) +/- high-dose rate (HDR) brachytherapy to treat this population. Our primary objectives were to evaluate complete response rates of targeted lesions after radiation and calculate our 5-year in-field control (IFC) rate. Secondary objectives were to assess radiation-related toxicities, chemotherapy free-interval (CFI), as well as post-radiation progression-free (PFS) and overall survival (OS). PFS and OS were defined from radiation start to either progression or death/last follow-up, respectively. This was a heavily pre-treated cohort of 17 recurrent OC patients with a median follow-up of 28.4 months (range 4.5-166.4) after radiation completion. 52.9% had high-grade serous histology and 4 (23.5%) had isolated vaginal/perirectal disease. Four (23.5%) patients had in-field failures at 3.7, 11.2, 24.5, and 27.5 months after start of radiation, all treated with definitive dosing of radiation therapy. Patients who were platinum-sensitive prior to radiation had similar median PFS (6.5 vs. 13.4 months, log-rank p = 0.75), but longer OS (71.1 vs 18.8 months, log-rank p = 0.05) than their platinum-resistant counterparts. Excluding patients with low-grade histology or who were treated with palliative radiation, median CFI was 14.2 months (range 4.7 - 33.0). Radiation was well tolerated with 2 (12.0%) experiencing grade 3/4 gastrointestinal/genitourinary toxicities. In conclusion, radiation to treat locally recurrent vaginal/perirectal lesions in heavily pre-treated OC patients is safe and may effectively provide IFC.

2.
Epidemiol Psychiatr Sci ; 26(6): 587-595, 2017 12.
Article in English | MEDLINE | ID: mdl-28789715

ABSTRACT

Generalised anxiety disorder (GAD) is a common psychiatric illness characterised by selective morpho-functional brain alterations. The breath of neuroimaging studies investigating the neural basis of GAD is extensive; however, its pathophysiology is still largely unknown. Specifically for proton Magnetic Resonance Spectroscopy (¹H MRS) investigations, which have the aim of identifying differences in metabolite levels between conditions in key brain areas, often showed contrasting results. Indeed, there are selected ¹H MRS studies reporting deficits of key metabolites in GAD patients; however, collectively the literature remains mixed with respect to consistency of major findings. In this review, we evaluate published ¹H MRS studies on GAD with the final aim of providing a comprehensive overview of the extent of neurometabolic dysfunctions associated with GAD. Interestingly, the majority of the studies reviewed showed altered metabolite levels in the dorsolateral prefrontal cortex and hippocampus suggesting regional specificity. These results also provide evidence of the utility of ¹H MRS not only for elucidating the pathophysiology of neuropsychiatric diseases, but also for the identification of more beneficial and targeted pharmacological interventions. Additionally, future studies are warranted to overcome methodological differences observed across the studies.


Subject(s)
Anxiety Disorders/diagnosis , Anxiety Disorders/metabolism , Choline/metabolism , Hippocampus/metabolism , Prefrontal Cortex/metabolism , Proton Magnetic Resonance Spectroscopy , Anxiety Disorders/pathology , Hippocampus/diagnostic imaging , Humans , Neuroimaging , Prefrontal Cortex/diagnostic imaging
3.
Epidemiol Psychiatr Sci ; 26(2): 122-128, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28103961

ABSTRACT

Relevant biochemicals of the brain can be quantified in vivo, non-invasively, using proton Magnetic Resonance Spectroscopy (¹H MRS). This includes metabolites associated with neural general functioning, energetics, membrane phospholipid metabolism and neurotransmission. Moreover, there is substantial evidence of implication of the frontal and prefrontal areas in the pathogenesis of psychotic disorders such as schizophrenia. In particular, the anterior cingulate cortex (ACC) plays an important role in cognitive control of emotional and non-emotional processes. Thus the study of its extent of biochemistry dysfunction in the early stages of psychosis is of particular interest in gaining a greater understanding of its aetiology. In this review, we selected ¹H MRS studies focused on the ACC of first-episode psychosis (FEP). Four studies reported increased glutamatergic levels in FEP, while other four showed preserved concentrations. Moreover, findings on FEP do not fully mirror those in chronic patients. Due to conflicting findings, larger longitudinal ¹H MRS studies are expected to further explore glutamatergic neurotransmission in ACC of FEP in order to have a better understanding of the glutamatergic mechanisms underlying psychosis, possibly using ultra high field MR scanners.


Subject(s)
Brain/metabolism , Gyrus Cinguli/metabolism , Proton Magnetic Resonance Spectroscopy/methods , Psychotic Disorders/metabolism , Schizophrenia/metabolism , Emotions , Female , Humans , Male , Prefrontal Cortex/metabolism , Psychotic Disorders/physiopathology , Schizophrenia/physiopathology
4.
Hum Exp Toxicol ; 35(6): 585-97, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26270564

ABSTRACT

INTRODUCTION: Thyroid epithelial cells produce moderate amounts of reactive oxygen species that are physiologically required for thyroid hormone synthesis. Nevertheless, when they are produced in excessive amounts, they may become toxic. OBJECTIVE: The present study is aimed to compare the lipid peroxidation (LPO), antioxidant enzymes - superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and non-protein thiols (reduced glutathione (GSH)) in human thyroid tissues with malignant and non-malignant disorders. DESIGN AND METHODS: The study used human thyroid tissues and blood samples from 157 women (147 diseased and 10 normal). Thyroid hormones, oxidative stress markers and antioxidants were estimated by standard methods. RESULTS: LPO significantly increased in most of the papillary thyroid carcinoma (PTC: 82.9%) and follicular thyroid adenoma (FTA: 72.9%) tissues, whilst in a majority of nodular goitre (69.2%) and Hashimoto's thyroiditis (HT: 73.7%) thyroid tissues, it remained unaltered. GSH increased in PTC (55.3%), remained unaltered in FTA (97.3%) and all other goiter samples studied. SOD increased in PTC (51.1%) and all other malignant thyroid tissues studied. CAT remained unaltered in PTC (95.7%), FTA (97.3%) and all other non-malignant samples (HT, MNG, TMNG) studied. GPx increased in PTC (63.8%), all other malignant thyroid tissues and remained unaltered in many of the FTA (91.9%) tissues and all other non-malignant samples (HT, MNG, TMNG) studied. CONCLUSIONS: In the case of non-malignant thyroid tumours, the oxidant-antioxidant balance was undisturbed, whilst in malignant tumours the balance was altered, and the change in r value observed in the LPO and SOD pairs between normal and PTC tissues and also in many pairs with multi-nodular goitre (MNG)/toxic MNG tissues may be used as a marker to differentiate/detect different malignant/non-malignant thyroid tumours.


Subject(s)
Antioxidants/metabolism , Carcinoma/metabolism , Goiter/metabolism , Lipid Peroxidation , Thyroid Gland/metabolism , Thyroid Neoplasms/metabolism , Adult , Carcinoma/surgery , Catalase/blood , Female , Glutathione Peroxidase/blood , Goiter/surgery , Humans , Middle Aged , Superoxide Dismutase/blood , Thyroid Gland/surgery , Thyroid Hormones/blood , Thyroid Neoplasms/surgery , Thyrotropin/blood
5.
Brain Cogn ; 99: 1-7, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26188845

ABSTRACT

BACKGROUND: Attention-Deficit/Hyperactivity Disorder (ADHD) is a heterogeneous, neurodevelopmental disorder which co-occurs often with Reading Disability (RD). ADHD with and without RD consistently have higher inattentive ratings compared with typically developing controls, with co-occurring ADHD and RD also demonstrating impaired phonological processing. Accordingly, inattention has been associated with greater phonological impairment, though the neural correlates of the association are poorly understood from a functional neuroimaging perspective. It was postulated that only the co-occurring subgroup would demonstrate hypoactivation of posterior, left hemispheric, reading-related areas and, to a lesser extent, alterations in right hemispheric, attention areas compared with controls. METHODS: A novel word rhyming Continuous Performance Task assesses functional activation differences in phonology- and attention-related areas between three groups: ten boys with ADHD and RD, fourteen boys with ADHD without RD, and fourteen typically developing controls. Subjects respond to words that rhyme with a target word as mono- and disyllabic, English words are visually presented over 90s blocks. RESULTS: Behavioral performance was not different between groups. Some hypoactivation of left hemispheric, reading-related areas was apparent in ADHD and RD, but not ADHD without RD, compared with controls. Right hemispheric, attention areas showed alterations in both ADHD subgroups relative to controls; however, the differences for each subgroup were dissimilar. CONCLUSIONS: The dorsal decoding subnetwork may not be grossly compromised in ADHD with Reading Disability. The role of cognitive impairments, including the level of inattention, on phonology requires clarification from a neuroimaging perspective.


Subject(s)
Attention Deficit Disorder with Hyperactivity/physiopathology , Attention/physiology , Dominance, Cerebral/physiology , Dyslexia/physiopathology , Phonetics , Semantics , Verbal Learning/physiology , Adolescent , Adult , Brain Mapping , Child , Female , Humans , Magnetic Resonance Imaging , Male , Neuropsychological Tests , Reference Values
6.
Biofouling ; 30(6): 741-9, 2014.
Article in English | MEDLINE | ID: mdl-24866988

ABSTRACT

Underwater noise is increasing globally, largely due to increased vessel numbers and international ocean trade. Vessels are also a major vector for translocation of non-indigenous marine species which can have serious implications for biosecurity. The possibility that underwater noise from fishing vessels may promote settlement of biofouling on hulls was investigated for the ascidian Ciona intestinalis. Spatial differences in biofouling appear to be correlated with spatial differences in the intensity and frequency of the noise emitted by the vessel's generator. This correlation was confirmed in laboratory experiments where C. intestinalis larvae showed significantly faster settlement and metamorphosis when exposed to the underwater noise produced by the vessel generator. Larval survival rates were also significantly higher in treatments exposed to vessel generator noise. Enhanced settlement attributable to vessel generator noise may indicate that vessels not only provide a suitable fouling substratum, but vessels running generators may be attracting larvae and enhancing their survival and growth.


Subject(s)
Biofouling , Ciona intestinalis/growth & development , Cues , Noise , Ships , Animals , Larva/growth & development , Metamorphosis, Biological/physiology , Oceans and Seas
7.
J Steroid Biochem Mol Biol ; 130(1-2): 105-24, 2012 May.
Article in English | MEDLINE | ID: mdl-22386953

ABSTRACT

Gender bias in the incidence of thyroid cancer is well known, however, the underlying mechanism is largely unknown. The current study determines variations in the molecular characteristics of thyroid cancers between men and women. Normal and cancerous thyroid tissues were collected from a total of 125 men and women who underwent surgical thyroidectomy. Testosterone levels in serum and thyroid cancer tissues were elevated in women while it decreased in men compared to respective control groups; whereas, ligand binding activity increased in men and decreased in women. Androgen receptor (AR) mRNA expression increased in a majority of men while it decreased in a majority of women except those with follicular thyroid carcinoma (FTC). In thyroid cancers of women, Pearson's correlation analysis showed a positive correlation of AR mRNA with AR protein, CBP and Sp1, whereas AR mRNA showed a negative correlation with p53. In case of men, AR mRNA showed a positive correlation with AR and cyclin D1 proteins in papillary thyroid carcinoma (PTC); and CBP and Sp1 in follicular thyroid adenoma (FTA), whereas AR mRNA showed a positive correlation with p53. Our study identified for the first time that AR is posttranscriptionally regulated by miR-124a in thyroid cancer tissues. Further, our in vitro studies with a PTC cell line (NPA-87-1) showed miR-124a as the potent inhibitor of AR that impairs cell proliferation even in the presence of testosterone. Thus, the current study suggests that: (i) the varying pattern of testosterone level and AR status in thyroid tissues of men and women may predispose to the gender specific incidence of thyroid tumors and (ii) miR-124a plays a significant role in determining the AR gene expression pattern and thus, androgen mediated thyroid tumor growth.


Subject(s)
Receptors, Androgen/genetics , Thyroid Neoplasms/genetics , Thyroid Neoplasms/metabolism , Adenocarcinoma, Follicular , Adult , Cell Line, Tumor , Female , Humans , Male , MicroRNAs/genetics , MicroRNAs/metabolism , Prejudice , Receptors, Androgen/metabolism , Reverse Transcriptase Polymerase Chain Reaction
8.
Biofouling ; 28(1): 65-72, 2012.
Article in English | MEDLINE | ID: mdl-22235850

ABSTRACT

Underwater sound plays an important role in the settlement behaviour of many coastal organisms. Large steel-hulled vessels are known to be a major source of underwater sound in the marine environment. The possibility that underwater sound from vessels may promote biofouling of hulls through triggering natural larval settlement cues was investigated for the mussel, Perna canaliculus. The mussel larvae showed significantly faster settlement when exposed to the underwater noise produced by a 125-m long steel-hulled passenger and freight ferry. Median time to attachment on the substrata (ie settlement) was reduced by 22% and the time taken for all experimental larvae to settle was reduced by 40% relative to a silent control. There was no difference in the survival of the mussel larvae among the various noise treatments. The decrease in settlement time of the mussel larvae appeared to correlate with the intensity of the vessel sound, suggesting that underwater sound emanating from vessels may be an important factor in exacerbating hull fouling by mussels.


Subject(s)
Biofouling , Perna/physiology , Ships , Sound , Animals , Bivalvia/growth & development , Bivalvia/physiology , Larva/growth & development , Larva/physiology , Perna/growth & development , Seawater
9.
J Intellect Disabil Res ; 54(8): 749-61, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20633203

ABSTRACT

BACKGROUND: Although work stress can impede the capacity of direct support professionals and contribute to mental health challenges, external (i.e. work social support) and internal resources (i.e. an internal locus of control) have been shown to help DSPs cope more actively. We examined how work stress was associated with depression, with a particular focus on the role of resources. METHOD: Direct support professionals (n = 323) who serve adults with intellectual and developmental disabilities from five community-based organisations completed a cross-sectional, self-administered survey which measured work stress, work support, locus of control, and depression. RESULTS: Multiple regression analyses demonstrated that work stress was positively associated with depression, while resources were negatively associated with depression. In particular, work support moderated the effects of client disability stress, supervisory support lessened the effects of role conflict, and locus of control moderated the effects of workload. CONCLUSIONS: Such findings suggest the importance of external and internal resources for staff mental health. This research underscores the need for strong work social support systems and interventions to help staff manage work stressors.


Subject(s)
Depression/etiology , Developmental Disabilities/rehabilitation , Health Personnel/psychology , Intellectual Disability/rehabilitation , Internal-External Control , Social Support , Stress, Psychological/etiology , Work/psychology , Aged , Conflict, Psychological , Cross-Sectional Studies , Female , Humans , Male , Mental Health , Middle Aged , Regression Analysis , Role , Surveys and Questionnaires , Workload
10.
Biopolymers ; 86(1): 11-22, 2007 May.
Article in English | MEDLINE | ID: mdl-17211888

ABSTRACT

Deuteron T(1) and T(2) was studied as a function of hydration in homopolyglycine (PG) and homopolyproline (PP). Water deuteron relaxation rates in PG conform to a hydration model involving two types of primary hydration sites where water is directly bonded to the polymer. Once these sites are filled, additional water only bonds to water molecules at the primary sites and in so doing affect their dynamics. PP exhibits an anomalous T(1) and T(2) hydration dependence which has been interpreted in terms of a cooperative water molecule-PP molecule helical conformational rearrangement which occurs once a certain hydration level is reached. The proposal of a water-PP structure is tested using molecular dynamics simulations.


Subject(s)
Nuclear Magnetic Resonance, Biomolecular/methods , Peptides/chemistry , Water/chemistry , Microscopy, Electron, Transmission
11.
Mol Psychiatry ; 8(3): 316-23, 251, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12660804

ABSTRACT

In vivo (31)P magnetic resonance spectroscopy ((31)P MRS) studies have shown abnormal membrane phospholipid metabolism in the prefrontal cortex (PF) in the early course of schizophrenia. It is unclear, however, whether these alterations also represent premorbid risk indicators in schizophrenia. In this paper, we report in vivo (31)P MRS data on children and adolescents at high risk (HR) for schizophrenia. In vivo (31)P MRS studies of the PF were conducted on 16 nonpsychotic HR offspring of parents with schizophrenia or schizoaffective disorder, and 37 age-matched healthy comparison (HC) subjects. While 11 of the HR subjects had evidence of Axis I psychopathology (HR-P), five HR subjects had none (HR-NP). We quantified the freely mobile phosphomonoester (PME) and phosphodiester (PDE) levels reflecting membrane phospholipid precursors and breakdown products, respectively, and the relatively broad signal underlying PDE and PME peaks, comprised of less mobile molecules with PDE and PME moieties (eg, synaptic vesicles and phosphorylated proteins). Compared to HC subjects, HR subjects had reductions in freely mobile PME; the differences were accounted for mainly by the HR-P subjects. Additionally, HR-P subjects showed increases in the broad signal underlying the PME and PDE peaks in the PF. To conclude, these data demonstrate new evidence for decreased synthesis of membrane phospholipids and possibly altered content or the molecular environment of synaptic vesicles and/or phosphoproteins in the PF of young offspring at risk for schizophrenia. Follow-up studies are needed to examine the predictive value of these measures for future emergence of schizophrenia in at-risk individuals.


Subject(s)
Prefrontal Cortex/metabolism , Psychotic Disorders/genetics , Psychotic Disorders/metabolism , Schizophrenia/genetics , Schizophrenia/metabolism , Adolescent , Cell Membrane/metabolism , Child , Female , Humans , Magnetic Resonance Spectroscopy , Male , Phospholipids/metabolism , Phosphorus Isotopes , Psychotic Disorders/epidemiology , Risk Factors , Schizophrenia/epidemiology
12.
Magn Reson Med ; 45(3): 390-6, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11241695

ABSTRACT

In a typical, in vivo (31)P brain spectrum, the phosphomonoester (PME) and phosphodiester (PDE) spectral region not only contains signals from freely mobile PMEs and PDEs (which are anabolic and catabolic products of membrane phospholipids) but also signals of broader underlying lineshapes from less-mobile molecules. In general, either the PME and PDE resonances are quantified as a combined value of freely mobile metabolites plus less-mobile molecules or the broader underlying signal is reduced/eliminated prior to or post data collection. In this study, a postprocessing method that segregates and quantifies the individual contributions of the freely mobile metabolites and the less-mobile molecules is introduced. To demonstrate the precision and accuracy of the method, simulated data and in vivo (31)P brain spectroscopy data of healthy individuals were quantified. The ability to segregate and quantify these various PME and PDE contributions provides additional spectral information and improves the accuracy of the interpretation of (31)P spectroscopy results. Magn Reson Med 45:390-396, 2001.


Subject(s)
Brain/physiology , Magnetic Resonance Spectroscopy , Phosphates/metabolism , Phospholipids/metabolism , Signal Processing, Computer-Assisted , Adult , Female , Humans , Male , Reference Values , Sensitivity and Specificity
13.
Hum Mol Genet ; 9(18): 2617-27, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-11063721

ABSTRACT

Three founder transgenic mice were generated with a 108 kb human genomic fragment containing the entire autosomal dominant polycystic kidney disease (ADPKD) gene, PKD1, plus the tuberous sclerosis gene, TSC2. Two lines were established (TPK1 and TPK3) each with approximately 30 copies of the transgene. Both lines produced full-length PKD1 mRNA and polycystin-1 protein that was developmentally regulated, similar to the endogenous pattern, with expression during renal embryogenesis and neonatal life, markedly reduced at the conclusion of renal development. Tuberin expression was limited to the brain. Transgenic animals from both lines (and the TPK2 founder animal) often displayed a renal cystic phenotype, typically consisting of multiple microcysts, mainly of glomerular origin. Hepatic cysts and bile duct proliferation, characteristic of ADPKD, were also seen. All animals with two copies of the transgenic chromosome developed cysts and, in total, 48 of the 100 transgenic animals displayed a cystic phenotype. To test the functionality of the transgene, animals were bred with the Pkd1(del34) knockout mouse. Both transgenic lines rescued the embryonically lethal Pkd1(del34/del34) phenotype, demonstrating that human polycystin-1 can complement for loss of the endogenous protein. The rescued animals were viable into adulthood, although more than half developed hepatic cystic disease in later life, similar to the phenotype of older Pkd1(del34/+) animals. The TPK mice have defined a minimal area that appropriately expresses human PKD1. Furthermore, this model indicates that over-expression of normal PKD1 can elicit a disease phenotype, suggesting that the level of polycystin-1 expression may be relevant in the human disease.


Subject(s)
Polycystic Kidney, Autosomal Dominant/genetics , Polycystic Kidney, Autosomal Dominant/pathology , Proteins/metabolism , Transgenes/genetics , Animals , Blotting, Southern , Blotting, Western , Gene Deletion , Gene Dosage , Genetic Complementation Test , Genotype , Humans , Immunohistochemistry , Kidney/metabolism , Kidney/pathology , Liver/metabolism , Liver/pathology , Mice , Mice, Knockout , Mice, Transgenic , Molecular Sequence Data , Nuclease Protection Assays , Phenotype , Polycystic Kidney, Autosomal Dominant/metabolism , Proteins/genetics , RNA, Messenger/analysis , RNA, Messenger/genetics , Repressor Proteins/analysis , TRPP Cation Channels , Tuberous Sclerosis Complex 2 Protein , Tumor Suppressor Proteins
14.
Biol Psychiatry ; 48(5): 357-68, 2000 Sep 01.
Article in English | MEDLINE | ID: mdl-10978719

ABSTRACT

Our knowledge of the biological basis of schizophrenia has significantly increased with the contribution of in vivo proton and phosphorus magnetic resonance spectroscopy (MRS), a noninvasive tool that can assess the biochemistry from a localized region in the human body. Studies thus far suggest altered membrane phospholipid metabolism at the early stage of illness and reduced N-acetylaspartate, a measure of neuronal volume/viability in chronic schizophrenia. Inconsistencies remain in the literature, in part due to the complexities in the MRS methodology. These complexities of in vivo spectroscopy make it important to understand the issues surrounding the design of spectroscopy protocols to best address hypotheses of interest. This review addresses these issues, including 1) understanding biochemistry and the physiologic significance of metabolites; 2) the influence of acquisition parameters combined with spin-spin and spin-lattice relaxation effects on the MRS signal; 3) the composition of spectral peaks and the degree of overlapping peaks, including the broader underlying peaks; 4) factors affecting the signal-to-noise ratio; 5) the various types of localization schemes; and 6) the objectives to produce accurate and reproducible quantification results. The ability to fully exploit the potentials of in vivo spectroscopy should lead to a protocol best optimized to address the hypotheses of interest.


Subject(s)
Magnetic Resonance Imaging/methods , Schizophrenia/pathology , Animals , Brain Chemistry , Humans , Image Processing, Computer-Assisted , Schizophrenia/metabolism
15.
Biol Psychiatry ; 48(5): 369-80, 2000 Sep 01.
Article in English | MEDLINE | ID: mdl-10978720

ABSTRACT

Magnetic resonance spectroscopy allows investigation of in vivo neurochemical pathology of schizophrenia. "First generation" studies, focusing on phosphorus and proton magnetic resonance spectroscopy, have suggested alterations in membrane phospholipid metabolism and reductions in N-acetyl aspartate in the frontal and temporal lobes. Some discrepancies remain in the literature, perhaps related to the variations in medication status and phase of illness in the patients examined, as well as in magnetic resonance spectroscopy methodology; the pathophysiologic significance of the findings also remains unclear. Technologic advances in magnetic resonance spectroscopy in recent years have expanded the potential to measure several other metabolites of interest such as the neurotransmitters glutamate and gamma-aminobutyric acid and macromolecules such as membrane phospholipids and synaptic proteins. Issues of sensitivity, specificity, measurement reliability, and functional significance of the magnetic resonance spectroscopy findings need to be further clarified. The noninvasive nature of magnetic resonance spectroscopy allows longitudinal studies of schizophrenia both in its different phases and among individuals at genetic risk for this illness. Future studies also need to address confounds of prior treatment and illness chronicity, take advantage of current pathophysiologic models of schizophrenia, and be hypothesis driven.


Subject(s)
Magnetic Resonance Imaging/methods , Schizophrenia/pathology , Animals , Humans , Image Processing, Computer-Assisted , Schizophrenia/metabolism
16.
Brain Res Bull ; 53(4): 455-69, 2000 Nov 01.
Article in English | MEDLINE | ID: mdl-11137004

ABSTRACT

Magnetic resonance spectroscopy (MRS) is a non-invasive physical technique that is routinely used to determine the quantity and structure of organic molecules in solution. Technical advances that have expanded the usefulness of this technique include: (1) high resolution MRS to identify and quantify individual molecules present in complex mixtures of tissue extracts; (2) in vivo MRS techniques to non-invasively monitor metabolites in humans; (3) structure determination of proteins of moderate size; and (4) improved structure characterization of solids and liquid crystals, such as the detection of phase changes in membranes. The focus of this review is on the first two technical advances mentioned above. The strengths of MRS as a research tool to investigate molecular alterations in disease states include ease of sample preparation, minimum sample manipulation, avoidance of the preparation of derivatives, and the ability to analyze an unfractionated sample. The strengths of MRS in the clinic are its ability to measure neuronal metabolite levels non-invasively in humans and its potential for disease diagnosis, monitoring disease progression, and assessing the efficacy of experimental therapies.


Subject(s)
Brain/metabolism , Developmental Disabilities/metabolism , Neurodegenerative Diseases/metabolism , Neurons/metabolism , Aging , Alzheimer Disease/metabolism , Animals , Brain/growth & development , Brain/pathology , Developmental Disabilities/pathology , Humans , Magnetic Resonance Spectroscopy , Models, Neurological , Neurodegenerative Diseases/pathology
17.
Br J Haematol ; 107(1): 33-48, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10520023

ABSTRACT

Multipotential progenitor and stem cells occur with a low frequency in haemopoietic tissue. As a result, it is often difficult to obtain sufficient numbers of cells to undertake many of the assays that would be informative about the molecular events involved in the regulation of lineage-affiliated genes within these multipotent cells. To circumvent this problem, we have used the myeloproliferative leukaemia virus (MPLV) to generate a phenotypically diverse array of haemopoietic progenitors from adult mouse bone marrow and embryonic blood. These cells could be expanded to perform a variety of analyses that would not previously have been possible using analogous primary cells. The validity of these assays was supported by the observation that the phenotype of several MPLV-infected lines was very similar to previously described primary haemopoietic progenitor cells. By using mice transgenic for the human alpha and beta globin gene clusters, we have shown that human genes may also be investigated. In addition, this strategy has a wide potential applicability including the rescue of haemopoietic progenitors from mouse embryos lacking genes critical for their survival as well as the study of any haemopoietic gene for which an appropriate transgenic mouse is available.


Subject(s)
Globins/genetics , Hematopoietic Stem Cells/virology , Human T-lymphotropic virus 1/genetics , Leukemia Virus, Murine/genetics , Animals , Cell Lineage , Clone Cells , Humans , Megakaryocytes , Mice , Mice, Inbred C57BL , Mice, Inbred CBA , Ribonucleases/metabolism , Tumor Cells, Cultured
18.
Epilepsia ; 39(3): 267-73, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9578043

ABSTRACT

PURPOSE: Reduced levels of N-acetylaspartate (NAA) in temporal lobes responsible for temporal lobe epilepsy have been observed consistently in proton magnetic resonance spectroscopy (MRS) studies. METHODS: We investigated the potential of proton MRS to detect low NAA outside of the temporal lobes in patients with non-lesional partial extratemporal epilepsy. Proton MR spectroscopic imaging (MRSI) data of both frontal lobes and central/postcentral regions were obtained in 20 such patients and 16 normal control subjects. The epileptogenic region was determined by an extensive clinical-EEG investigation, including the recording of habitual seizures in each patient, and intracranial EEG recordings in 10 patients. RESULTS: The relative NAA resonance intensities (i.e., NAA/phosphocreatine plus creatine (CR(t)), NAA/choline-containing metabolites (Cho(t)) and NAA/Cr(t) + Cho(t)), were all significantly reduced throughout the spectroscopic image as compared with that of the controls. Furthermore, reduction of the NAA ratios was greater in the epileptogenic region as compared with the nonepileptogenic regions, on EEG investigation. CONCLUSIONS: In vivo proton MRSI of patients with nonlesional partial extratemporal epilepsy detected evidence of widespread neuronal damage or dysfunction that was greatest in the region of seizure focus.


Subject(s)
Cerebral Cortex/metabolism , Epilepsies, Partial/diagnosis , Magnetic Resonance Spectroscopy , Adult , Aspartic Acid/analogs & derivatives , Aspartic Acid/metabolism , Choline/metabolism , Electrodes, Implanted , Epilepsies, Partial/metabolism , Epilepsy, Frontal Lobe/diagnosis , Epilepsy, Frontal Lobe/metabolism , Female , Humans , Male , Phosphocreatine/metabolism , Protons
19.
Neurobiol Aging ; 19(6): 511-5, 1998.
Article in English | MEDLINE | ID: mdl-10192209

ABSTRACT

Alterations in phospholipid metabolites are a characteristic abnormality of Alzheimer's disease (AD). Many of these alterations have been demonstrated by magnetic resonance spectroscopy (MRS) studies of postmortem tissue. Phosphodiesters appear to be elevated late in the disease and phosphomonoesters appear to be elevated early in the disease and then decrease. Second to aging, the most robust risk factor for AD identified to date is the presence of the E4 allele of apolipoprotein-E (Apo-E). Because apolipoproteins are intimately involved in lipid metabolism, this study was performed to determine if the presence of the Apo-E4 allele affects the abnormalities in phospholipid metabolites in AD brain. Perchloric acid extracts from 12 Apo-E 3/3, 31 3/4, 6 4/4 AD brains and 5 Apo-E 3/3 control brains were studied by both proton magnetic resonance spectroscopy and phosphorus-31 magnetic resonance spectroscopy. When the E4-positive AD samples were compared with the 3/3 AD samples, an exaggeration in both phosphomonoester and phosphodiester abnormalities was observed. The decrease in N-acetyl-L-aspartate (NAA) was also exaggerated. These results suggest membrane phospholipid metabolite alterations observed in AD are more severe in the presence of the Apo-E4 allele.


Subject(s)
Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Apolipoproteins E/genetics , Phospholipids/metabolism , Aged , Aged, 80 and over , Alzheimer Disease/pathology , Apolipoprotein E4 , Brain/metabolism , Brain/pathology , Female , Humans , Magnetic Resonance Spectroscopy , Male , Middle Aged
20.
Ann N Y Acad Sci ; 826: 282-306, 1997 Sep 26.
Article in English | MEDLINE | ID: mdl-9329700

ABSTRACT

In vitro and in vivo 31P magnetic resonance (MR) spectroscopy studies of Alzheimer's disease (AD) brain have revealed alterations in membrane phospholipid metabolism and high-energy phosphate metabolism. Mildly demented AD patients compared with control subjects have increased levels of phosphomonoesters, decreased levels of phosphocreatine and probably adenosine diphosphate and an increased oxidative metabolic rate. As the dementia worsens, levels of phosphomonoesters decrease and levels of phosphocreatine and adenosine di-phosphate increase. The changes in oxidative metabolic rate suggest that the AD brain is under energetic stress. The phosphomonoester findings support our in vitro findings and implicate basic defects in membrane metabolism in AD brain. MR spectroscopy provides new diagnostic insights and a noninvasive method to follow the progression of the disease and the metabolic response to therapeutic interventions.


Subject(s)
Alzheimer Disease/metabolism , Brain/metabolism , Magnetic Resonance Spectroscopy , Alzheimer Disease/diagnosis , Amyloid beta-Peptides/metabolism , Apolipoproteins E/metabolism , Energy Metabolism , Humans , Lipid Bilayers/metabolism , Models, Biological , Models, Molecular
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