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1.
Genes (Basel) ; 14(12)2023 Dec 04.
Article in English | MEDLINE | ID: mdl-38136997

ABSTRACT

BACKGROUND: Myocardial bridging (MB) is a congenital coronary artery anomaly that has limited molecular disease state characterization. Though a large portion of individuals may be asymptomatic, the myocardial ischemia caused by this anomaly can lead to angina, acute coronary syndrome, coronary artery disease, and sudden cardiac death in patients. OBJECTIVE: This study aims to summarize and consolidate the current literature regarding the genomic associations of myocardial bridge development and, in doing so, prompt further investigation into the molecular basis of myocardial bridge development. METHODS: We performed a systematic literature review of myocardial bridging using the key search terms "Myocardial Bridging" AND ("Gene" OR "Allelic Variants" OR "Genomic") in the databases of PubMed, CINAHL, EMBASE, and Cochran. We then performed a detailed review of the resulting abstracts and a full-text screening, summarizing these findings in this report. RESULTS: In total, we identified eight articles discussing the associated genomics behind MB development. Studies included review articles, case reports and genomic studies that led to the discussion of several genes: DES (E434K), FBN1 (I1175M), and COMMD10; MACROD2, SLMAP, MYH7 (A1157G), and DPP6 (A714T); MYH7 (A862V); SCN2B (E31D); and NOTCH1 (R2313Q), and to the discussion of miRNAs (miR-29b, miR-151-3p, miR-126, miR-503-3p, and miR-645). CONCLUSIONS: Our study is the first to summarize the genes and molecular regulators related to myocardial bridges as they exist in the current literature. This work concludes that definitive evidence is lacking, warranting much broader genetic and genomic studies.


Subject(s)
Coronary Artery Disease , MicroRNAs , Myocardial Bridging , Humans , Myocardial Bridging/complications , Coronary Artery Disease/etiology , Genomics
2.
JMIR Form Res ; 7: e45376, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37713239

ABSTRACT

BACKGROUND: An effective and scalable information retrieval (IR) system plays a crucial role in enabling clinicians and researchers to harness the valuable information present in electronic health records. In a previous study, we developed a prototype medical IR system, which incorporated a semantically based query recommendation (SBQR) feature. The system was evaluated empirically and demonstrated high perceived performance by end users. To delve deeper into the factors contributing to this perceived performance, we conducted a follow-up study using query log analysis. OBJECTIVE: One of the primary challenges faced in IR is that users often have limited knowledge regarding their specific information needs. Consequently, an IR system, particularly its user interface, needs to be thoughtfully designed to assist users through the iterative process of refining their queries as they encounter relevant documents during their search. To address these challenges, we incorporated "query recommendation" into our Electronic Medical Record Search Engine (EMERSE), drawing inspiration from the success of similar features in modern IR systems for general purposes. METHODS: The query log data analyzed in this study were collected during our previous experimental study, where we developed EMERSE with the SBQR feature. We implemented a logging mechanism to capture user query behaviors and the output of the IR system (retrieved documents). In this analysis, we compared the initial query entered by users with the query formulated with the assistance of the SBQR. By examining the results of this comparison, we could examine whether the use of SBQR helped in constructing improved queries that differed from the original ones. RESULTS: Our findings revealed that the first query entered without SBQR and the final query with SBQR assistance were highly similar (Jaccard similarity coefficient=0.77). This suggests that the perceived positive performance of the system was primarily attributed to the automatic query expansion facilitated by the SBQR rather than users manually manipulating their queries. In addition, through entropy analysis, we observed that search results converged in scenarios of moderate difficulty, and the degree of convergence correlated strongly with the perceived system performance. CONCLUSIONS: The study demonstrated the potential contribution of the SBQR in shaping participants' positive perceptions of system performance, contingent upon the difficulty of the search scenario. Medical IR systems should therefore consider incorporating an SBQR as a user-controlled option or a semiautomated feature. Future work entails redesigning the experiment in a more controlled manner and conducting multisite studies to demonstrate the effectiveness of EMERSE with SBQR for patient cohort identification. By further exploring and validating these findings, we can enhance the usability and functionality of medical IR systems in real-world settings.

3.
J Med Internet Res ; 24(4): e22124, 2022 04 04.
Article in English | MEDLINE | ID: mdl-35377331

ABSTRACT

BACKGROUND: Racial inequity persists for chronic disease outcomes amid the proliferation of health information technology (HIT) designed to support patients in following recommended chronic disease self-management behaviors (ie, medication behavior, physical activity, and dietary behavior and attending follow-up appointments). Numerous interventions that use consumer-oriented HIT to support self-management have been evaluated, and some of the related literature has focused on racial minorities who experience disparate chronic disease outcomes. However, little is known about the efficacy of these interventions. OBJECTIVE: This study aims to conduct a systematic review of the literature that describes the efficacy of consumer-oriented HIT interventions designed to support self-management involving African American and Hispanic patients with chronic diseases. METHODS: We followed an a priori protocol using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses)-Equity 2012 Extension guidelines for systematic reviews that focus on health equity. Themes of interest included the inclusion and exclusion criteria. We identified 7 electronic databases, created search strings, and conducted the searches. We initially screened results based on titles and abstracts and then performed full-text screening. We then resolved conflicts and extracted relevant data from the included articles. RESULTS: In total, there were 27 included articles. The mean sample size was 640 (SD 209.5), and 52% (14/27) of the articles focused on African American participants, 15% (4/27) of the articles focused on Hispanic participants, and 33% (9/27) included both. Most articles addressed 3 of the 4 self-management behaviors: medication (17/27, 63%), physical activity (17/27, 63%), and diet (16/27, 59%). Only 15% (4/27) of the studies focused on follow-up appointment attendance. All the articles investigated HIT for use at home, whereas 7% (2/27) included use in the hospital. CONCLUSIONS: This study addresses a key gap in research that has not sufficiently examined what technology designs and capabilities may be effective for underserved populations in promoting health behavior in concordance with recommendations.


Subject(s)
Health Equity , Medical Informatics , Chronic Disease , Exercise , Hispanic or Latino , Humans
4.
Br J Pharmacol ; 179(3): 358-370, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34600443

ABSTRACT

BACKGROUND AND PURPOSE: Lasmiditan is a novel selective 5-HT1F receptor agonist, recently approved for acute treatment of migraine. 5-HT1F receptors are widely expressed in the CNS and trigeminovascular system. Here, we have explored the therapeutic effects of 5-HT1F receptor activation in preclinical models of migraine and cluster headache. EXPERIMENTAL APPROACH: Electrical stimulation of the dura mater or the superior salivatory nucleus in anaesthetised rats evoked trigeminovascular or trigeminal-autonomic reflex activation at the level of the trigeminocervical complex. Additionally, cranial autonomic manifestations in response to trigeminal-autonomic reflex activation were measured, via anterior choroidal blood flow alterations. These responses were then challenged with lasmiditan. We explored the tissue distribution of mRNA for 5-HT1F receptors in human post-mortem tissue and of several 5-HT1 receptor subtypes in specific tissue beds. KEY RESULTS: Lasmiditan dose-dependently reduced trigeminovascular activation in a preclinical model of migraine. Lasmiditan also reduced superior salivatory nucleus-evoked activation of the trigeminal-autonomic reflex, but had no effect on cranial autonomic activation. mRNA profiling in human tissue showed expression of the 5-HT1F receptor in several structures relevant for migraine and cluster headache. CONCLUSION AND IMPLICATIONS: Our data suggest that lasmiditan acts, at least in part, as an anti-migraine agent by reducing trigeminovascular activation. Furthermore, our results highlight a clear action for lasmiditan in a preclinical model of cluster headache. Given the proven translational efficacy of this model, our data support the potential utility of lasmiditan as a therapeutic option for the acute treatment of cluster headache attacks. LINKED ARTICLES: This article is part of a themed issue on Advances in Migraine and Headache Therapy (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.3/issuetoc.


Subject(s)
Cluster Headache , Migraine Disorders , Animals , Benzamides , Cluster Headache/drug therapy , Migraine Disorders/drug therapy , Nociception , Piperidines , Pyridines , RNA, Messenger , Rats , Receptors, Serotonin , Serotonin , Receptor, Serotonin, 5-HT1F
5.
Appl Clin Inform ; 10(5): 859-869, 2019 10.
Article in English | MEDLINE | ID: mdl-31724143

ABSTRACT

BACKGROUND: Interactive data visualization and dashboards can be an effective way to explore meaningful patterns in large clinical data sets and to inform quality improvement initiatives. However, these interactive dashboards may have usability issues that undermine their effectiveness. These usability issues can be attributed to mismatched mental models between the designers and the users. Unfortunately, very few evaluation studies in visual analytics have specifically examined such mismatches between these two groups. OBJECTIVES: We aimed to evaluate the usability of an interactive surgical dashboard and to seek opportunities for improvement. We also aimed to provide empirical evidence to demonstrate the mismatched mental models between the designers and the users of the dashboard. METHODS: An interactive dashboard was developed in a large congenital heart center. This dashboard provides real-time, interactive access to clinical outcomes data for the surgical program. A mixed-method, two-phase study was conducted to collect user feedback. A group of designers (N = 3) and a purposeful sample of users (N = 12) were recruited. The qualitative data were analyzed thematically. The dashboards were compared using the System Usability Scale (SUS) and qualitative data. RESULTS: The participating users gave an average SUS score of 82.9 on the new dashboard and 63.5 on the existing dashboard (p = 0.006). The participants achieved high task accuracy when using the new dashboard. The qualitative analysis revealed three opportunities for improvement. The data analysis and triangulation provided empirical evidence to the mismatched mental models. CONCLUSION: We conducted a mixed-method usability study on an interactive surgical dashboard and identified areas of improvements. Our study design can be an effective and efficient way to evaluate visual analytics systems in health care. We encourage researchers and practitioners to conduct user-centered evaluation and implement education plans to mitigate potential usability challenges and increase user satisfaction and adoption.


Subject(s)
Electronic Health Records , Heart Diseases/congenital , Heart Diseases/surgery , Quality of Health Care , User-Computer Interface , Humans
6.
Biochim Biophys Acta ; 1800(3): 398-404, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20036319

ABSTRACT

BACKGROUND: Factor VIII is the cofactor for Factor X activation by Factor IXa. Activated Factor X, Factor Xa, in turn activates prothrombin in a sequence that leads to fibrin clot formation at the site of vascular injury. Although the biochemistry of the cascade has been well studied, the molecular mechanism underlying the cofactor role of Factor VIII is not understood. METHODS: We screened a bacterial peptide display library with Factor IXa and Factor X co-immobilized on tosylactivated Dynabeads which were then used as platelet surrogates. Validation of peptide selection procedure and comparison of Factor VIII-like cofactor activity of oxidoreductases was performed using COATEST assays. Determination of Factor VIII as a folding catalyst with potential disulphide isomerase activity was determined using the RNase A renaturation assay. RESULTS: We set out to identify the cofactor requirements of the Factor IXa/Factor X procoagulant complex by random peptide display, and isolated a peptide with the active-site sequence, CGPC, of thioredoxin. This peptide was able to activate Factor X in a Factor IXa-dependent manner. Redox catalysts or oxidoreductases with homologous active-site vicinal cysteines such as PDI and DsbA also mimicked Factor VIII in their requirement of Factor IXa in Factor X activation. However, the cofactor activity of these peptides was up to a 1000-fold lower than that of Factor VIII and they were therefore unable to catalyse blood coagulation. Factor X activation by PDI and by Factor VIII was abolished by oxidation in an isolated system, which implies a possible role for thiol-disulphide exchange in the activity of the tenase complex. Using scrambled RNase A as a surrogate substrate, we also found that Factor VIII could renature this enzyme. CONCLUSION: Our findings suggest that Factor VIII may be a specialized folding catalyst with disulphide isomerase activity. We suggest that it is this activity that may underlie its cofactor function in Factor X activation, and that this function is interchangeable with classical oxidoreductases. GENERAL SIGNIFICANCE: The possible involvement of thiol-disulphide interchange as a mechanism underlying Factor VIII cofactor activity may provide some insight into the biochemistry of the intrinsic tenase complex.


Subject(s)
Factor VIII/physiology , Factor Xa/metabolism , Oxidoreductases/metabolism , Thioredoxins/metabolism , Blood Coagulation , Blood Platelets/physiology , Catalysis , Coenzymes/metabolism , Disulfides/metabolism , Factor VIII/genetics , Factor VIII/metabolism , Factor Xa/genetics , Glutathione/metabolism , Humans , Oxidation-Reduction , Oxidoreductases/genetics , Protein Folding , Recombinant Proteins/metabolism , Thioredoxins/genetics
7.
Brain Res ; 1152: 215-27, 2007 Jun 04.
Article in English | MEDLINE | ID: mdl-17434465

ABSTRACT

Aberrant glutamatergic neurotransmission may underlie the pathogenesis of schizophrenia and metabotropic glutamate receptors (mGluRs) have been implicated in the disease. We have established the localization of the group III mGluR subtype, mGluR8, in the human body and investigated the biological effects of the selective mGluR8 agonist (S)-3,4-dicarboxyphenylglycine ((S)-3,4-DCPG) in schizophrenia-related animal models. The mGlu8 receptor has a widespread CNS distribution with expression observed in key brain regions associated with schizophrenia pathogenesis including the hippocampus. (S)-3,4-DCPG inhibited synaptic transmission and increased paired-pulse facilitation in rat hippocampal slices supporting the role of mGluR8 as a presynaptic autoreceptor. Using the rat Maximal Electroshock Seizure Threshold (MEST) test, (S)-3,4-DCPG (30 mg/kg, i.p.) reduced seizure activity confirming the compound to be centrally active following systemic administration. (S)-3,4-DCPG did not reverse (locomotor) hyperactivity induced by acute administration of phenylcyclidine (PCP, 1-32 mg/kg, i.p.) or amphetamine (3-30 mg/kg, i.p.) in Sprague-Dawley rats. However, 10 nmol (i.c.v.) (S)-3.4-DCPG did reverse amphetamine-induced hyperactivity in mice although it also inhibited spontaneous locomotor activity at this dose. In addition, mGluR8 null mutant mouse behavioral phenotyping revealed an anxiety-related phenotype but no deficit in sensorimotor gating. These data provide a potential role for mGluR8 in anxiety and suggest that mGluR8 may not be a therapeutic target for schizophrenia.


Subject(s)
Brain/metabolism , Receptors, Metabotropic Glutamate/physiology , Schizophrenia/metabolism , Amphetamine/pharmacology , Animals , Anticonvulsants/pharmacology , Anxiety/genetics , Anxiety/metabolism , Autoreceptors/agonists , Autoreceptors/biosynthesis , Autoreceptors/physiology , Benzoates/pharmacology , Central Nervous System Stimulants/pharmacology , Dentate Gyrus/drug effects , Dentate Gyrus/physiology , Disease Models, Animal , Electroshock , Glycine/analogs & derivatives , Glycine/pharmacology , Humans , Male , Mice , Mice, Knockout , Motor Activity/drug effects , Phencyclidine/pharmacology , Rats , Rats, Sprague-Dawley , Receptors, Metabotropic Glutamate/agonists , Receptors, Metabotropic Glutamate/genetics , Schizophrenia/physiopathology , Seizures/etiology , Seizures/prevention & control , Synapses/physiology , Synaptic Transmission/drug effects
8.
J Recept Signal Transduct Res ; 26(3): 159-78, 2006.
Article in English | MEDLINE | ID: mdl-16777713

ABSTRACT

Eight members of the TRP-melastatin (TRPM) subfamily have been identified, whose physiological functions and distribution are poorly characterized. Although tissue expression and distribution patterns have been reported for individual TRPM channels, comparisons between individual studies are not possible because of variations in analysis techniques and tissue selection. We report here a comparative analysis of the expression patterns of all of the human TRPM channels in selected peripheral tissues and the central nervous system (CNS) using two distinct but complimentary approaches: TaqMan and SYBR Green real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). These techniques generated comparative distribution profiles and demonstrated tissue-specific co-expression of TRPM mRNA species, indicating significant potential for the formation of heteromeric channels. TRPM channels 2, 4, 5, 6, and 7 in contrast to 1, 3, and 8 are widely distributed in the CNS and periphery. The tissues demonstrating highest expression for individual family members were brain (TRPM1), brain and bone marrow (TRPM2), brain and pituitary (TRPM3), intestine and prostate (TRPM4), intestine, pancreas, and prostate (TRPM5), intestine and brain (TRPM6), heart, pituitary, bone, and adipose tissue (TRPM7), and prostate and liver (TRPM8). The data reported here will guide the elucidation of TRPM channel physiological functions.


Subject(s)
TRPM Cation Channels/genetics , Base Sequence , DNA Primers/genetics , Female , Gene Expression Profiling , Humans , Male , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/statistics & numerical data , Sensitivity and Specificity , TRPM Cation Channels/classification , Tissue Distribution
9.
J Recept Signal Transduct Res ; 26(3): 179-98, 2006.
Article in English | MEDLINE | ID: mdl-16777714

ABSTRACT

We report the detailed expression profile of TRPM2 mRNA within the human central nervous system (CNS) and demonstrate increased TRPM2 mRNA expression at 1 and 4 weeks following ischemic injury in the rat transient middle cerebral artery occlusion (tMCAO) stroke model. Microglial cells play a key role in pathology produced following ischemic injury in the CNS and possess TRPM2, which may contribute to stroke-related pathological responses. We show that TRPM2 mRNA is present in the human C13 microglial cell line and is reduced by antisense treatment. Activation of C13 cells by interleukin-1beta leads to a fivefold increase of TRPM2 mRNA demonstrating transcriptional regulation. To confirm mRNA distribution correlated with functional expression, we combined electrophysiology, Ca2+ imaging, and antisense approaches. C13 microglia exhibited, when stimulated with hydrogen peroxide (H2O2), increased [Ca2+]i, which was reduced by antisense treatment. Moreover, patch-clamp recordings from C13 demonstrated that increased intracellular adenosine diphosphoribose (ADPR) or extracellular H2O2 induced an inward current, consistent with activation of TRPM2. In addition we confirm the functional expression of a TRPM2-like conductance in primary microglial cultures derived from rats. Activation of TRPM2 in microglia during ischemic brain injury may mediate key aspects of microglial pathophysiological responses.


Subject(s)
Microglia/metabolism , Stroke/genetics , Stroke/metabolism , TRPM Cation Channels/genetics , TRPM Cation Channels/metabolism , Animals , Base Sequence , Calcium Signaling/drug effects , Cell Line , Central Nervous System/metabolism , Disease Models, Animal , Gene Expression Regulation/drug effects , Humans , Hydrogen Peroxide/pharmacology , Interleukin-1/pharmacology , Male , Microglia/drug effects , Middle Cerebral Artery , RNA, Antisense/administration & dosage , RNA, Antisense/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Tissue Distribution
10.
Drug Metab Dispos ; 34(6): 1063-9, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16531474

ABSTRACT

Drug-induced changes in expression of cytochrome P450 (P450) genes are a significant issue in the preclinical development of pharmaceuticals. For example, preclinically, P450 induction can affect safety studies by reducing the systemic exposure of a compound undergoing toxicological evaluation, thus limiting the exposure that can be safely investigated in patients. Therefore, the induction potential of candidate drugs has been studied as part of the drug development process, typically using protein and/or catalytic end points. However, measuring changes in the levels of mRNA using TaqMan technology offers the opportunity to investigate this issue with the advantages of better dynamic range and specific enzyme identification. Here, we describe the TaqMan application to study ex vivo the P450 gene induction in the rat. Initially, livers from rats dosed with the prototypic P450 inducers beta-napthoflavone (BNF), phenobarbital (PB), dexamethasone (DEX), and clofibric acid (CLO) were analyzed for mRNA levels of CYP1A1, 1A2, 2B1, 2B2, 2E1, 3A2, 3A23, and 4A1 and compared with control animals. The maximum fold induction of mRNA varied: 2500-fold for CYP1A1 with BNF, 680-fold for CYP2B1 with PB, 59-fold for CYP3A23 with DEX, and 16-fold for CYP4A1 with CLO. This method was then applied to estimate the inductive potential of putative drug candidates undergoing rodent toxicological evaluation. We present a summary of these data that demonstrates the sensitivity and specificity of the TaqMan assay to distinguish between inducers and noninducers and that offers a highly specific alternative to the quantification of drug effects on P450 expression using immunodetection and substrate metabolism.


Subject(s)
Cytochrome P-450 Enzyme System/biosynthesis , Liver/metabolism , Reverse Transcriptase Polymerase Chain Reaction/methods , Animals , Aryl Hydrocarbon Hydroxylases/biosynthesis , Aryl Hydrocarbon Hydroxylases/genetics , Catalysis , Cytochrome P-450 CYP1A1/biosynthesis , Cytochrome P-450 CYP1A1/genetics , Cytochrome P-450 CYP2B1/biosynthesis , Cytochrome P-450 CYP2B1/genetics , Cytochrome P-450 CYP3A , Cytochrome P-450 Enzyme System/genetics , Dexamethasone/pharmacology , Drug Evaluation, Preclinical , Enzyme Induction , Liver/drug effects , Liver/enzymology , Male , Phenobarbital/pharmacology , RNA, Messenger/analysis , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Reproducibility of Results , Taq Polymerase , beta-Naphthoflavone/pharmacology
11.
DNA Cell Biol ; 24(7): 410-31, 2005 Jul.
Article in English | MEDLINE | ID: mdl-16008510

ABSTRACT

Administration of endotoxin (LPS) in humans results in profound physiological responses, including activation of peripheral blood mononuclear cells and the release of inflammatory factors. The time course of the response of selected inflammatory proteins was examined in healthy subjects (n = 6) administered a single intravenous dose of the purified derivative of endotoxin (3.0 ng/kg). Microarray analysis demonstrated changes in the expression of a number of genes, which were confirmed in separate in vitro endotoxin stimulation experiments. Subsequent TaqMan analysis of genes of interest indicated time-dependent changes in the expression of many of these genes. This included pre-B cell enhancing factor, which was identified on microarray analysis as being markedly upregulated following endotoxin stimulation. Protein expression of the genes examined by TaqMan analysis was measured and demonstrated the appearance of tumor necrosis factor (TNF)-alpha and sTNF-R proteins in the plasma beginning within 1 h after dosing, followed by other cytokines/ inflammatory markers (e.g., IL-1ra, G-CSF, IL-6, IL-8, and IL-10) and suppressors of cytokine signaling (SOCS-1 and SOCS-3). In general, cytokine protein expression correlated well with gene expression; however, the temporal profile of expression of some genes did not correlate well with the protein data. For many of these proteins, the lack of correlation was attributable to alternate tissue sources, which were demonstrated on TaqMan analysis. Principal component analysis indicated that cytokines could be grouped according to their temporal pattern of response, with most transcript levels returning to baseline 24 h following endotoxin administration. The combination of cDNA microarray and TaqMan analysis to identify and quantify changes in gene expression, along with the analysis of protein expression, can be useful in investigating inflammatory and other diseases.


Subject(s)
Cytokines/metabolism , Endotoxins/administration & dosage , Gene Expression Profiling , Gene Expression Regulation/drug effects , Proteins/analysis , Adolescent , Adult , Endotoxins/pharmacology , Granulocyte Colony-Stimulating Factor/metabolism , Humans , Inflammation/pathology , Injections, Intravenous , Interleukin-1/metabolism , Interleukin-10/metabolism , Interleukin-6/metabolism , Interleukin-8/metabolism , Kinetics , Male , Microarray Analysis , Nicotinamide Phosphoribosyltransferase , Polymerase Chain Reaction , Proteins/metabolism , RNA, Messenger/analysis , RNA, Messenger/metabolism , Tumor Necrosis Factor-alpha/metabolism , Up-Regulation
13.
Neurobiol Aging ; 26(6): 813-23, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15718039

ABSTRACT

Apolipoprotein (apo) E4 is a risk factor for Alzheimer's disease (AD) and other neurodegenerative diseases, compared to wild-type apoE3. The mechanism(s) is unknown. One possibility, demonstrated in peripheral tissue cell lines, is that apoE stimulates nitric oxide synthase (NOS) via a receptor-dependent signalling pathway and that apoE4 generates inappropriate amounts of nitric oxide (NO) compared to apoE3. Prior to biochemical investigations, we have quantified the expression of several candidate receptor genes, including low-density lipoprotein-receptor (LDL-r) family members and scavenger receptor class B, types I and II (SR-BI/II), as well as the three NOS isoenzymes and protein kinase B (Akt), in 38 human cell lines, of which 12 derive from brain. Expression of apoE receptor 2 (apoER2), a known signalling receptor in brain, was readily detected in SH-SY-5Y and CCF-STTG1 cells, common models of neurons and astrocytes, respectively, and was highest in H4 neuroglioma, NT-2 precursor cells and IMR-32 neuroblastoma cells. Transcripts of the other lipoprotein receptors were widely, but variably, distributed across the different cell types. Of particular note was the predominant expression of SR-BII over SR-BI in many of the brain-derived cells. As the C-terminus of SR-BII, like apoER2, contains potential SH3 signalling motifs, we suggest that in brain SR-BII functions as a signal transducer receptor.


Subject(s)
Astrocytes/metabolism , Brain/metabolism , Gene Expression Profiling/methods , Low Density Lipoprotein Receptor-Related Protein-1/metabolism , Neurons/metabolism , Receptors, Immunologic/metabolism , Reverse Transcriptase Polymerase Chain Reaction/methods , Apolipoproteins E/metabolism , CD36 Antigens , Cell Line , Humans , Nitric Oxide/metabolism , Receptors, Scavenger , Scavenger Receptors, Class B
14.
Comp Funct Genomics ; 6(5-6): 268-76, 2005.
Article in English | MEDLINE | ID: mdl-18629217

ABSTRACT

The aryl hydrocarbon receptor nuclear translocator (ARNT) and cathepsin K (CTSK) genes lie in a tandem head-to-tail arrangement on human chromosome 1. The two genes are in extremely close proximity; the usual CTSK transcription start site is less than 1.4 kb downstream of the end of the longest reported ARNT transcript. By generating an RT-PCR product that overlaps both the 3' end of ARNT and the 5' end of CTSK, we show that ARNT transcripts may extend through the ARNT-CTSK intergenic region and progress into the CTSK gene. Furthermore, by using quantitative RT-PCR from several tissues to detect the ARNT expression signature in CTSK introns, we show that ARNT transcripts can read through into CTSK as far as CTSK intron 3, extending approximately 3.7 kb downstream of the end of the longest previously described ARNT mRNA. Given that ARNT and CTSK are expressed in an overlapping range of tissues, ARNT read-through may have a negative impact on CTSK transcript levels by interfering with CTSK expression. We also present evidence for novel CTSK transcripts following sequence analysis of CTSK-derived ESTs and RT-PCR products. These transcripts show alternate 5' splicing and or 5' extension and are sometimes initiated from a cryptic alternative promoter which is upstream of the known CTSK promoter and possibly in the 3' UTR of ARNT.

15.
DNA Seq ; 15(1): 1-8, 2004 Feb.
Article in English | MEDLINE | ID: mdl-15354348

ABSTRACT

Murine NGD5 is a gene identified from NG108-15 cells which is postulated to be involved in opioid receptor function. Here we report the cloning and characterization of a cDNA C20orf9-003 (ACI-1) encoding the human orthologue of the mouse NGD5. Analysis of the genomic structure revealed that C20orf9-003 (ACI-1) contains 13 exons and 12 introns, spanning 52.5kb of genomic DNA and is a variant of C20orf9. Chromosomal localization of human C20orf9-003 (ACI-1) assigned this gene to chromosome 20q13.12. Genes at this locus have been associated with the progression and possibly the development of various cancers. In addition several linkage studies support the possibility that one or more genes affecting obesity are located in 20q13. No function can be clearly assigned to C20orf9-003 (ACI-1), however, the protein has a cytoplasmic subcellular location and the secondary structure contains a Rossman fold like feature which is found in many nucleotide binding proteins.


Subject(s)
Chromosomes, Human, Pair 20/genetics , Proteins/genetics , Amino Acid Sequence , Animals , Binding Sites , Breast Neoplasms/genetics , Chromosome Mapping , Cloning, Molecular , DNA, Complementary/genetics , Exons , Female , Genetic Markers , Genetic Predisposition to Disease , Humans , Immunohistochemistry , Male , Mice , Molecular Sequence Data , Molecular Weight , Obesity/genetics , Prostatic Neoplasms/genetics , Proteins/chemistry , Proteins/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Sequence Alignment , Sequence Homology, Amino Acid
16.
Br J Pharmacol ; 143(3): 411-21, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15351778

ABSTRACT

The human hyperpolarization-activated cyclic nucleotide-gated 1 (hHCN1) subunit was heterologously expressed in mammalian cell lines (CV-1 and CHO) and its properties investigated using whole-cell patch-clamp recordings. Activation of this recombinant channel, by membrane hyperpolarization, generated a slowly activating, noninactivating inward current. The pharmacological properties of hHCN1-mediated currents resembled those of native hyperpolarization-activated currents (I(h)), that is, blockade by Cs(+) (99% at 5 mm), ZD 7288 (98% at 100 microm) and zatebradine (92% at 10 microm). Inhibition of the hHCN1-mediated current by ZD 7288 was apparently independent of prior channel activation (i.e. non-use-dependent), whereas that induced by zatebradine was use-dependent. The VR1 receptor antagonist capsazepine inhibited hHCN1-mediated currents in a concentration-dependent (IC(50)=8 microm), reversible and apparently non-use-dependent manner. This inhibitory effect of capsazepine was voltage-independent and associated with a leftward shift in the hHCN1 activation curve as well as a dramatic slowing of the kinetics of current activation. Elevation of intracellular cAMP or extracellular K(+) significantly enhanced aspects of hHCN1 currents. However, these manipulations did not significantly affect the capsazepine-induced inhibition of hHCN1. The development of structural analogues of capsazepine may yield compounds that could selectively inhibit HCN channels and prove useful for the treatment of neurological disorders where a role for HCN channels has been described.


Subject(s)
Capsaicin/analogs & derivatives , Capsaicin/pharmacology , Ion Channels/physiology , Animals , Benzazepines/pharmacology , CHO Cells , Cell Line , Cricetinae , Cricetulus , Cyclic AMP/pharmacology , Cyclic Nucleotide-Gated Cation Channels , Dose-Response Relationship, Drug , Electric Stimulation , Humans , Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels , Ion Channels/antagonists & inhibitors , Ion Channels/genetics , Membrane Potentials/drug effects , Patch-Clamp Techniques , Potassium/pharmacology , Potassium Channels , Pyrimidines/pharmacology , Time Factors , Transfection
17.
Psychopharmacology (Berl) ; 177(1-2): 1-14, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15205870

ABSTRACT

RATIONALE: Neuromedin-U (NmU) is an agonist at NMU1R and NMU2R. The brain distribution of NmU and its receptors, in particular NMU2R, suggests widespread central roles for NmU. In agreement, centrally administered NmU affects feeding behaviour, energy expenditure and pituitary output. Further central nervous system (CNS) roles for NmU warrant investigation. OBJECTIVES: To investigate the CNS role of NmU by mapping NMU1R and NMU2R mRNA and measuring the behavioural, endocrine, neurochemical and c-fos response to intracerebroventricular (i.c.v.) NmU. METHODS: Binding affinity and functional potency of rat NmU was determined at human NMU1R and NMU2R. Expression of NMU1R and NMU2R mRNA in rat and human tissue was determined using semi-quantitative reverse-transcription polymerase chain reaction. In in-vivo studies, NmU was administered i.c.v. to male Sprague-Dawley rats, and changes in grooming, motor activity and pre-pulse inhibition (PPI) were assessed. In further studies, plasma endocrine hormones, [DOPAC + HVA]/[dopamine] and [5-HIAA]/[5-HT] ratios and levels of Fos-like immunoreactivity (FLI) were measured 20 min post-NmU (i.c.v.). RESULTS: NmU bound to NMU1R ( K(I), 0.11+/-0.02 nM) and NMU2R ( K(I), 0.21+/-0.05 nM) with equal affinity and was equally active at NMU1R (EC(50), 1.25+/-0.05 nM) and NMU2R (EC(50), 1.10+/-0.20 nM) in a functional assay. NMU2R mRNA expression was found at the highest levels in the CNS regions of both rat and human tissues. NMU1R mRNA expression was restricted to the periphery of both species with the exception of the rat amygdala. NmU caused a marked increase in grooming and motor activity but did not affect PPI. Further, NmU decreased plasma prolactin but did not affect levels of corticosterone, luteinising hormone or thyroid stimulating hormone. NmU elevated levels of 5-HT in the frontal cortex and hypothalamus, with decreased levels of its metabolites in the hippocampus and hypothalamus, but did not affect dopamine function. NmU markedly increased FLI in the nucleus accumbens, frontal cortex and central amygdala. CONCLUSIONS: These data provide further evidence for widespread roles for NmU and its receptors in the brain.


Subject(s)
Central Nervous System/drug effects , Central Nervous System/metabolism , Membrane Proteins/agonists , Membrane Proteins/metabolism , Neuropeptides/administration & dosage , Receptors, Neurotransmitter/agonists , Receptors, Neurotransmitter/metabolism , Animals , Cell Line , Dose-Response Relationship, Drug , Humans , Injections, Intraventricular , Rats , Rats, Sprague-Dawley , Swine
18.
Mar Biotechnol (NY) ; 6(5): 485-92, 2004.
Article in English | MEDLINE | ID: mdl-15129328

ABSTRACT

A plasmid containing human coagulation factor VII (hFVII) complementary DNA regulated by a cytomegalovirus promoter was microinjected into fertilized eggs of zebrafish, African catfish, and tilapia. The active form of hFVll was detected in the fish embryos by various assays. This positive expression of human therapeutic protein in fish embryos demonstrates the possibility of exploitation of transgenic fish as bioreactors.


Subject(s)
Bioreactors , Factor VII/metabolism , Fishes/metabolism , Transgenes/genetics , Zygote/metabolism , Animals , Blood Coagulation/drug effects , Cytomegalovirus/genetics , DNA, Complementary/genetics , Enzyme-Linked Immunosorbent Assay , Factor VII/genetics , Factor VII/pharmacology , Genetic Vectors/genetics , Humans , Microinjections , Photometry , Promoter Regions, Genetic/genetics
19.
Brain Res Mol Brain Res ; 122(1): 24-34, 2004 Mar 17.
Article in English | MEDLINE | ID: mdl-14992813

ABSTRACT

The human tissue distribution of the nineteen known human regulators of G-protein signaling (RGS) is described. Measurement of RGS mRNA levels in human brain and in nine peripheral tissues revealed striking tissue preferences in gene expression. Five RGS members were identified with enriched expression in brain. RGS4, RGS7, RGS8, RGS11 and RGS17 were all significantly expressed in striatal regions including the nucleus accumbens and putamen. RGS4 had the highest measured levels of mRNA expression and was highly enriched in the gyrus of the cortex and in the parahippocampus. RGS7 and RGS17 had overlapping distribution profiles and were both noticeably enriched in the cerebellum. Several RGS family members showed high expression in peripheral tissues. RGS5 was preferentially expressed in heart, and RGS1, RGS13, RGS18 and GAIP were predominately expressed in lymphocytes. RGS1 was also highly enriched in the lung, as was RGS2 and RGS16. Five family members, RGS3, RGS9, RGS10, RGS 12 and RGS14 had a broad and overlapping mRNA distribution. These results suggest roles of the individual RGS members in a diversity of functions in humans and support a role of several RGS members in the regulation of central nervous system function via modulation of signaling by G-protein coupled receptors.


Subject(s)
Central Nervous System/metabolism , Gene Expression Regulation , RGS Proteins/metabolism , Aged , Aged, 80 and over , Central Nervous System/anatomy & histology , Female , Gene Expression Profiling/methods , Humans , Male , RGS Proteins/classification , RGS Proteins/genetics , RNA, Messenger/biosynthesis , Reverse Transcriptase Polymerase Chain Reaction/methods
20.
Brain Res Mol Brain Res ; 118(1-2): 10-23, 2003 Oct 21.
Article in English | MEDLINE | ID: mdl-14559350

ABSTRACT

We have recently shown that UDP-glucose, and some related UDP-sugars, are potent agonists of the novel G protein-coupled receptor GPR105 (recently re-named P2Y(14)). GPR105 is widely expressed throughout many brain regions and peripheral tissues of human and rodents, and couples to a pertussis toxin-sensitive G protein. To further characterise the role of GPR105, we demonstrate by immunohistochemistry with receptor-specific antiserum that GPR105 protein is widely distributed throughout the post mortem human brain where it is localised to glial cells, and specifically co-localises with astrocytes. Using quantitative RT-PCR we also show that GPR105 mRNA exhibits a restricted expression profile in an array of human cell lines and primary cells, with prominent expression detected in immune cells including neutrophils, lymphocytes, and megakaryocytic cells. To investigate the G protein selectivity of GPR105, we used chimeric Galpha subunits (Galpha(qi5), Galpha(qo5), and Galpha(qs5)) and an intracellular Ca(2+) mobilisation assay to demonstrate that GPR105 couples to Galpha subunits of the G(i/o) family but not to G(s) family proteins or to endogenous G(q/11) proteins in HEK-293 cells. Finally, we show that expression of GPR105 mRNA in the rat brain is up-regulated by immunologic challenge with lipopolysaccharide. Based on these observations, we propose that G(i/o)-coupled GPR105 might play an important role in peripheral and neuroimmune function in response to extracellular UDP-sugars.


Subject(s)
Astrocytes/metabolism , Brain/metabolism , Leukocytes/metabolism , Receptors, G-Protein-Coupled/metabolism , Receptors, Immunologic/metabolism , Receptors, Purinergic P2/metabolism , Animals , Astrocytes/immunology , Brain/immunology , Cell Line , GTP-Binding Protein alpha Subunits, Gi-Go/metabolism , GTP-Binding Protein alpha Subunits, Gq-G11/metabolism , Gene Expression Regulation/drug effects , Gene Expression Regulation/immunology , Glucose/immunology , Humans , Immunohistochemistry , Leukocytes/immunology , Lipopolysaccharides/immunology , Male , Neuroimmunomodulation/immunology , Protein Subunits/genetics , Protein Subunits/metabolism , RNA, Messenger/metabolism , Rats , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/immunology , Receptors, Immunologic/genetics , Receptors, Immunologic/immunology , Receptors, Purinergic P2/genetics , Receptors, Purinergic P2/immunology , Receptors, Purinergic P2Y , Up-Regulation/immunology , Uridine Diphosphate/immunology
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