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1.
J Syst Integr Neurosci ; 6(2)2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33614164

RESUMEN

Research into the neurogenetic basis of addiction identified and characterized by Reward Deficiency Syndrome (RDS) includes all drug and non-drug addictive, obsessive and compulsive behaviors. We are proposing herein that a new model for the prevention and treatment of Substance Use Disorder (SUD) a subset of RDS behaviors, based on objective biologic evidence, should be given serious consideration in the face of a drug epidemic. The development of the Genetic Addiction Risk Score (GARS) followed seminal research in 1990, whereby, Blum's group identified the first genetic association with severe alcoholism published in JAMA. While it is true that no one to date has provided adequate RDS free controls there have been many studies using case -controls whereby SUD has been eliminated. We argue that this deficiency needs to be addressed in the field and if adopted appropriately many spurious results would be eliminated reducing confusion regarding the role of genetics in addiction. However, an estimation, based on these previous literature results provided herein, while not representative of all association studies known to date, this sampling of case- control studies displays significant associations between alcohol and drug risk. In fact, we present a total of 110,241 cases and 122,525 controls derived from the current literature. We strongly suggest that while we may take argument concerning many of these so-called controls (e.g. blood donors) it is quite remarkable that there are a plethora of case -control studies indicating selective association of these risk alleles ( measured in GARS) for the most part indicating a hypodopaminergia. The paper presents the detailed methodology of the GARS. Data collection procedures, instrumentation, and the analytical approach used to obtain GARS and subsequent research objectives are described. Can we combat SUD through early genetic risk screening in the addiction field enabling early intervention by the induction of dopamine homeostasis? It is envisaged that GARS type of screening will provide a novel opportunity to help identify causal pathways and associated mechanisms of genetic factors, psychological characteristics, and addictions awaiting additional scientific evidence including a future meta- analysis of all available data -a work in progress.

2.
Mol Neurobiol ; 56(11): 7836-7850, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31124077

RESUMEN

Post-traumatic stress disorder (PTSD) is a severe polygenic disorder triggered by environmental factors. Many polymorphic genes, particularly the genetic determinants of hypodopaminergia (low dopamine function), associate with a predisposition to PTSD as well as substance use disorder. Support from the National Institutes of Health for neuroimaging research and molecular, genetic applied technologies has improved understanding of brain reward circuitry functions that have inspired the development of new innovative approaches to their early diagnosis and treatment of some PTSD symptomatology and addiction. This review presents psychosocial and genetic evidence that vulnerability or resilience to PTSD can theoretically be impacted by dopamine regulation. From a neuroscience perspective, dopamine is widely accepted as a major neurotransmitter. Questions about how to modulate dopamine clinically in order to treat and prevent PTSD and other types of reward deficiency disorders remain. Identification of genetic variations associated with the relevant genotype-phenotype relationships can be characterized using the Genetic Addiction Risk Score (GARS®) and psychosocial tools. Development of an advanced genetic panel is under study and will be based on a new array of genes linked to PTSD. However, for now, the recommendation is that enlistees for military duty be given the opportunity to voluntarily pre-test for risk of PTSD with GARS, before exposure to environmental triggers or upon return from deployment as part of PTSD management. Dopamine homeostasis may be achieved via customization of neuronutrient supplementation "Precision Behavioral Management" (PBM™) based on GARS test values and other pro-dopamine regulation interventions like exercise, mindfulness, biosensor tracking, and meditation.


Asunto(s)
Conducta , Estigma Social , Trastornos por Estrés Postraumático/psicología , Dopamina/metabolismo , Humanos , Trastornos por Estrés Postraumático/genética , Trastornos por Estrés Postraumático/terapia
3.
J Comp Pathol ; 168: 19-24, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31103054

RESUMEN

A 10-year-old neutered female domestic longhair cat was presented to a tertiary care veterinary hospital for evaluation of a right renal mass that was identified incidentally on abdominal radiographs and classified further as a sarcoma based on fine needle aspiration cytology. Further diagnostic workup, including ultrasound and cytology, identified a sarcoma in the left kidney. After approximately 1 month of conservative medical management, the clinical condition deteriorated and the cat was humanely destroyed. Post-mortem examination confirmed bilateral renal masses with multifocal infarction and extensive necrosis, and further identified a large mass at the apex of the heart as well as multiple pulmonary nodules. Microscopical examination of the masses identified a population of poorly-differentiated neoplastic spindle cells, consistent with sarcoma. Immunohistochemically, the neoplastic cells expressed smooth muscle actin and muscle-specific actin, but were negative for myoglobin and factor VIII. Phosphotungstic acid-haematoxylin staining was unable to identify cross-striations in the neoplastic cells. Based on these results and the pattern of lesion distribution, the cat was diagnosed with cardiac leiomyosarcoma with pulmonary and bilateral renal metastasis.


Asunto(s)
Enfermedades de los Gatos/patología , Neoplasias Cardíacas/veterinaria , Neoplasias Renales/veterinaria , Leiomiosarcoma/veterinaria , Animales , Gatos , Femenino
4.
Artículo en Inglés | MEDLINE | ID: mdl-30079290

RESUMEN

BACKGROUND: Human immunodeficiency virus (HIV) infection remains a serious immunological disease with new infections in the U.S. disproportionately reported in minority populations. For many years, the District of Columbia (DC) has reported the highest HIV infection rate in the nation. Drug abuse and addiction is also prevalent in DC and has traditionally been linked to HIV/AIDS because of the likelihood for opportunistic infections. Despite this data, the relationship between HIV status, drugs of abuse, and the incidence of neurological disorders are scarcely reported for minority populations. METHOD: We carried out a retrospective study on the prevalence of substance abuse in HIV and their association with neuropsychiatric comorbidities in an African American subpopulation in Washington DC. FINDINGS: Our data suggests an 86 percent prevalence of drug use in the HIV patients with neuropsychiatric comorbidities, with cocaine use being significantly higher in patients with major depressive disorder (MDD) and bipolar disorder (BD), whereas PCP use was associated with patients with schizophrenia. The mean CD4 count was elevated in patients with neuropsychiatric disease, and specifically in MDD patients. CD8 counts were elevated as expected for HIV status but were not influenced by disease diagnosis. A majority (2/3) of patients were on HAART therapy, however the records did not account for adherence. CONCLUSION: These data suggest that neuropsychiatric comorbidities are independent of HIV disease progression but are correlated with certain illicit drugs of abuse.

5.
Mol Psychiatry ; 23(6): 1496-1505, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-28485403

RESUMEN

Genetic variations and adverse environmental events in utero or shortly after birth can lead to abnormal brain development and increased risk of schizophrenia. γ-Aminobutyric acid (GABA), the major inhibitory neurotransmitter in the mammalian brain, plays a vital role in normal brain development. GABA synthesis is controlled by enzymes derived from two glutamic acid decarboxylase (GAD) genes, GAD1 and GAD2, both of which produce transcript isoforms. While the full-length GAD1 transcript (GAD67) has been implicated in the neuropathology of schizophrenia, the transcript structure of GAD1 in the human brain has not been fully characterized. In this study, with the use of RNA sequencing and PCR technologies, we report the discovery of 10 novel transcripts of GAD1 in the human brain. Expression levels of four novel GAD1 transcripts (8A, 8B, I80 and I86) showed a lifespan trajectory expression pattern that is anticorrelated with the expression of the full-length GAD1 transcript. In addition, methylation levels of two CpG loci within the putative GAD1 promoter were significantly associated with the schizophrenia-risk SNP rs3749034 and with the expression of GAD25 in dorsolateral prefrontal cortex (DLPFC). Moreover, schizophrenia patients who had completed suicide and/or were positive for nicotine exposure had significantly higher full-length GAD1 expression in the DLPFC. Alternative splicing of GAD1 and epigenetic state appear to play roles in the developmental profile of GAD1 expression and may contribute to GABA dysfunction in the PFC and hippocampus of patients with schizophrenia.


Asunto(s)
Glutamato Descarboxilasa/genética , Esquizofrenia/genética , Adolescente , Adulto , Empalme Alternativo/genética , Autopsia , Encéfalo/metabolismo , Niño , Preescolar , Metilación de ADN/genética , Femenino , Expresión Génica/genética , Variación Genética/genética , Glutamato Descarboxilasa/metabolismo , Hipocampo/metabolismo , Humanos , Recién Nacido , Masculino , Corteza Prefrontal/metabolismo , Regiones Promotoras Genéticas/genética , Isoformas de ARN/genética , ARN Mensajero/metabolismo , Esquizofrenia/metabolismo
7.
Mol Psychiatry ; 22(3): 417-429, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27457813

RESUMEN

Although the pathogenesis of schizophrenia (SCZ) is proposed to involve alterations of neural circuits via synaptic dysfunction, the underlying molecular mechanisms remain poorly understood. Recent exome sequencing studies of SCZ have uncovered numerous single-nucleotide variants (SNVs); however, the majority of these SNVs have unknown functional consequences, leaving their disease relevance uncertain. Filling this knowledge gap requires systematic application of quantitative and scalable assays to assess known and novel biological functions of genes. Here we demonstrate loss-of-function effects of multiple rare coding SNVs found in SCZ subjects in the GIT1 (G protein-coupled receptor kinase interacting ArfGAP 1) gene using functional cell-based assays involving coexpression of GIT1 and PAK3 (p21 protein (Cdc42/Rac)-activated kinase 3). Most notably, a GIT1-R283W variant reported in four independent SCZ cases was defective in activating PAK3 as well as MAPK (mitogen-activated protein kinase). Similar functional deficits were found for a de novo SCZ variant GIT1-S601N. Additional assays revealed deficits in the capacity of GIT1-R283W to stimulate PAK phosphorylation in cultured hippocampal neurons. In addition, GIT1-R283W showed deficits in the induction of GAD1 (glutamate decarboxylase 1) protein expression. Extending these functional assays to 10 additional rare GIT1 variants revealed the existence of an allelic series with the majority of the SCZ case variants exhibiting loss of function toward MAPK activation in a manner correlated with loss of PAK3 activation. Taken together, we propose that rare variants in GIT1, along with other genetic and environmental factors, cause dysregulation of PAK3 leading to synaptic deficits in SCZ.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Ciclo Celular/metabolismo , Quinasas p21 Activadas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Técnicas de Cultivo de Célula/métodos , Proteínas de Ciclo Celular/genética , Proteínas Activadoras de GTPasa/genética , Variación Genética/genética , Factores de Intercambio de Guanina Nucleótido/metabolismo , Células HEK293/metabolismo , Hipocampo/metabolismo , Humanos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Plasticidad Neuronal/genética , Plasticidad Neuronal/fisiología , Neuronas/metabolismo , Fosfoproteínas , Fosforilación , Polimorfismo de Nucleótido Simple/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Esquizofrenia/genética , Transducción de Señal/genética , Quinasas p21 Activadas/genética
8.
J Dev Orig Health Dis ; 8(2): 155-160, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28029335

RESUMEN

The brain is highly susceptible to adverse effects of drugs of abuse during early phases of life. Prenatal nicotine exposure (PNE), a preventable cause of gestational and infant mortality, can alter neuron wiring and induce sustained deficits in attention and learning. Here, a rat model of PNE (embryonic days 7-21) was used to examine the maturing hippocampus, which encodes new memories and processes emotional memory. Components of synaptic signaling were evaluated at postnatal day 14 (P14), a period of prolific synaptogenesis in rats, to determine if glutamatergic transmission-associated molecules are regulated in subregions of hippocampus as early as P14. PNE resulted in reduced expression of GluN2B, GluA2 and CaMKIIα, but elevated SNAP25 proteins specifically in the CA3 but not CA1. Only CaMKIIα was regulated in dentate gyrus at this age. These results suggest that glutamatergic and synaptic dysregulation of learning and memory may occur in hippocampus in a temporally and subregionally specific manner.


Asunto(s)
Región CA3 Hipocampal/efectos de los fármacos , Nicotina/farmacología , Agonistas Nicotínicos/farmacología , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Animales , Región CA3 Hipocampal/patología , Femenino , Embarazo , Ratas , Ratas Sprague-Dawley
9.
Chem Sci ; 6(1): 804-815, 2015 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-25642316

RESUMEN

Aiming towards the development of novel nootropic therapeutics to address the cognitive impairment common to a range of brain disorders, we set out to develop highly selective small molecule inhibitors of HDAC2, a chromatin modifying histone deacetylase implicated in memory formation and synaptic plasticity. Novel ortho-aminoanilide inhibitors were designed and evaluated for their ability to selectively inhibit HDAC2 versus the other Class I HDACs. Kinetic and thermodynamic binding properties were essential elements of our design strategy and two novel classes of ortho-aminoanilides, that exhibit kinetic selectivity (biased residence time) for HDAC2 versus the highly homologous isoform HDAC1, were identified. These kinetically selective HDAC2 inhibitors (BRD6688 and BRD4884) increased H4K12 and H3K9 histone acetylation in primary mouse neuronal cell culture assays, in the hippocampus of CK-p25 mice, a model of neurodegenerative disease, and rescued the associated memory deficits of these mice in a cognition behavioural model. These studies demonstrate for the first time that selective pharmacological inhibition of HDAC2 is feasible and that inhibition of the catalytic activity of this enzyme may serve as a therapeutic approach towards enhancing the learning and memory processes that are affected in many neurological and psychiatric disorders.

10.
Neuroscience ; 188: 168-81, 2011 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-21596105

RESUMEN

Untimely activation of nicotinic acetylcholine receptors (nAChRs) by nicotine results in short- and long-term consequences on learning and behavior. In this study, the aim was to determine how prenatal nicotine exposure affects components of glutamatergic signaling in the hippocampus during postnatal development. We investigated regulation of both nAChRs and glutamate receptors for AMPA and N-methyl-D-aspartate (NMDA), from postnatal day 1 (P1) to P63 after a temporally restricted exposure to saline or nicotine for 14 days in utero. We analyzed postsynaptic density components associated with AMPA receptor (AMPAR) and NMDA receptor (NMDAR) signaling: calmodulin (CaM), CaM Kinase II alpha (CaMKIIα), and postsynaptic density-95 (PSD95), as well as presynaptically localized synaptosomal-associated protein 25 (SNAP25). At P1, there was significantly heightened expression of AMPAR subunit GluR1 but not GluR2, and of NMDAR subunits NR1, NR2a, and NR2d but not NR2b. NR2c was not detectable. CaM, CaMKIIα, and PSD95 were also significantly upregulated at P1, together with presynaptic SNAP25. This enhanced expression of glutamate receptors and signaling proteins was concomitant with elevated levels of [³H]epibatidine (³H]EB) binding in prenatal nicotine-exposed hippocampus, indicating that α4ß2 nAChR may influence glutamatergic function in the hippocampus at P1. By P14, neither [³H]EB binding nor the expression levels of subunits GluR1, GluR2, NR1, NR2a, NR2b, NR2c, or NR2d seemed changed with prenatal nicotine. However, CaMKIIα was significantly upregulated with nicotine treatment while CaM showed downregulation at P14. The effects of nicotine persisted in P63 young adult brains which exhibited significantly downregulated GluR2, NR1, and NR2c expression levels in hippocampal homogenates and a considerably muted overall distribution of [³H]AMPA binding in areas CA1, CA2 and CA3, and the dentate gyrus. Our results suggest that prenatal nicotine exposure can regulate the glutamatergic signaling system throughout postnatal development by enhancing or inhibiting availability of AMPAR and NMDAR or their signaling components. The persistent depression, in adults, of the requisite NR1 subunit for NMDAR assembly, and of GluR2, important for assembly, trafficking, and biophysical properties of AMPAR, indicates that nicotine may alter ionotropic glutamate receptor stoichiometry and functional properties in adults after prenatally restricted nicotine exposure.


Asunto(s)
Hipocampo/efectos de los fármacos , Nicotina/toxicidad , Agonistas Nicotínicos/toxicidad , Efectos Tardíos de la Exposición Prenatal/metabolismo , Receptores AMPA/biosíntesis , Receptores de N-Metil-D-Aspartato/biosíntesis , Animales , Western Blotting , Femenino , Expresión Génica/efectos de los fármacos , Hipocampo/metabolismo , Embarazo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos
11.
Colorectal Dis ; 13(5): e83-4, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21435144

RESUMEN

AIM: To describe a new technique for the Soave trans-anal pull-through. METHOD: After the mucosectomy during a Soave's procedure, a laparoscopic wound retractor was used to line the distal rectal segment to facilitate delivery of the proximal bowel through a narrow scarred pelvis. RESULTS: The technique greatly assisted delivery of the proximal bowel and helped prevent mesenteric injury. CONCLUSION: Soave trans-anal pull-through is a difficult operation that is largely confined to specialist centres. We describe an improvement to the technique that greatly facilitates the procedure.


Asunto(s)
Canal Anal/cirugía , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Fístula Rectal/cirugía , Enfermedad Crónica , Humanos , Masculino
12.
Med Hypotheses ; 68(3): 484-92, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17141964

RESUMEN

Elderly surgical patients constitute a unique surgical group. They require special consideration in order to preempt the long term adverse effects of anesthesia. This paper examines the proposition that general anesthesia causes harm to elderly patients with its impact being felt long after the anesthetic agents are cleared from the body. One complication, Postoperative Cognitive Decline (POCD), is associated with the administration of anesthesia and deep sedation. Its' occurrence may herald an increase in morbidity and mortality. Based on both human and animal data, this paper outlines a unitary theoretical framework to explain these phenomena. If this hypothesis proves to be correct, anesthesiologist should consider regional rather than general anesthesia for equivalent surgical procedures to reduce POCD and consequently achieving superior patient outcome.


Asunto(s)
Anestesia General/efectos adversos , Anestesia General/mortalidad , Trastornos del Conocimiento/etiología , Anciano , Sistema Nervioso Central/fisiopatología , Enfermedades del Sistema Nervioso Central/etiología , Trastornos del Conocimiento/clasificación , Humanos , Complicaciones Posoperatorias/epidemiología
13.
J Lipid Res ; 42(10): 1543-51, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11590209

RESUMEN

Fenofibrate is a member of the fibrate class of hypolipidemic agents used clinically to treat hypertriglyceridemia and mixed hyperlipidemia. The fibrates were developed primarily on the basis of their cholesterol and triglyceride lowering in rodents. Fibrates have historically been ineffective at lowering triglycerides in experimentally-induced dyslipidemia in nonhuman primate models. The spontaneously obese rhesus monkey is a well-recognized animal model for the study of human obesity and type 2 diabetes, and many of these monkeys exhibit naturally occurring lipid abnormalities, including elevated triglycerides and low HDL cholesterol (HDL-C), similar to patients with type 2 diabetes. To explore whether the obese rhesus model was predictive of the lipid lowering effects of fibrates, we evaluated fenofibrate in six hypertriglyceridemic, hyperinsulinemic, nondiabetic animals in a 20-week, dose-escalating study. The study consisted of a 4-week baseline period, two treatment periods of 10 mg/kg twice daily (b.i.d) for 4 weeks and 30 mg/kg b.i.d. for 8 weeks, and a 4-week washout period. Fenofibrate (30 mg/kg b.i.d) decreased serum triglycerides 55% and LDL-C 27%, whereas HDL-C increased 35%. Apolipoproteins B-100 and C-III levels were also reduced 70% and 29%, respectively. Food intake, body weight, and plasma glucose were not affected throughout the study. Interestingly, plasma insulin levels decreased 40% during the 30 mg/kg treatment period, suggesting improvement in insulin sensitivity. These results support the use of obese rhesus monkey as an excellent animal model for studying the effects of novel hypolipidemic agents, particularly agents that impact serum triglycerides and HDL-C.


Asunto(s)
Fenofibrato/farmacología , Metabolismo de los Lípidos , Macaca mulatta/metabolismo , Obesidad/metabolismo , Secuencia de Aminoácidos , Animales , Apolipoproteínas/sangre , Secuencia de Bases , Glucemia/metabolismo , Western Blotting , Peso Corporal , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Clonación Molecular , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Fenofibrato/administración & dosificación , Fenofibrato/uso terapéutico , Perfilación de la Expresión Génica , Hiperlipidemias/tratamiento farmacológico , Hiperlipidemias/metabolismo , Insulina/sangre , Lípidos/sangre , Macaca mulatta/sangre , Masculino , Datos de Secuencia Molecular , Obesidad/sangre , Obesidad/tratamiento farmacológico , Receptores Citoplasmáticos y Nucleares/química , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Factores de Transcripción/química , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Triglicéridos/sangre , Triglicéridos/metabolismo
14.
Bioorg Med Chem Lett ; 11(9): 1225-7, 2001 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-11354382

RESUMEN

Using solid-phase, parallel-array synthesis, a series of urea-substituted thioisobutyric acids was synthesized and assayed for activity on the human PPAR subtypes. GW7647 (3) was identified as a potent human PPARalpha agonist with approximately 200-fold selectivity over PPARgamma and PPARdelta, and potent lipid-lowering activity in animal models of dyslipidemia. GW7647 (3) will be a valuable chemical tool for studying the biology of PPARalpha in human cells and animal models of disease.


Asunto(s)
Hipolipemiantes/síntesis química , Receptores Citoplasmáticos y Nucleares/agonistas , Factores de Transcripción/agonistas , Animales , Butiratos/farmacología , Cricetinae , Grasas de la Dieta/farmacología , Diseño de Fármacos , Hiperlipidemias/sangre , Hiperlipidemias/tratamiento farmacológico , Hipolipemiantes/farmacología , Compuestos de Fenilurea/farmacología
15.
Proc Natl Acad Sci U S A ; 98(9): 5306-11, 2001 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-11309497

RESUMEN

The peroxisome proliferator-activated receptors (PPARs) are dietary lipid sensors that regulate fatty acid and carbohydrate metabolism. The hypolipidemic effects of the fibrate drugs and the antidiabetic effects of the glitazone drugs in humans are due to activation of the alpha (NR1C1) and gamma (NR1C3) subtypes, respectively. By contrast, the therapeutic potential of the delta (NR1C2) subtype is unknown, due in part to the lack of selective ligands. We have used combinatorial chemistry and structure-based drug design to develop a potent and subtype-selective PPARdelta agonist, GW501516. In macrophages, fibroblasts, and intestinal cells, GW501516 increases expression of the reverse cholesterol transporter ATP-binding cassette A1 and induces apolipoprotein A1-specific cholesterol efflux. When dosed to insulin-resistant middle-aged obese rhesus monkeys, GW501516 causes a dramatic dose-dependent rise in serum high density lipoprotein cholesterol while lowering the levels of small-dense low density lipoprotein, fasting triglycerides, and fasting insulin. Our results suggest that PPARdelta agonists may be effective drugs to increase reverse cholesterol transport and decrease cardiovascular disease associated with the metabolic syndrome X.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Colesterol/metabolismo , Receptores Citoplasmáticos y Nucleares/agonistas , Factores de Transcripción/agonistas , Transportador 1 de Casete de Unión a ATP , Transportadoras de Casetes de Unión a ATP/genética , Animales , Apolipoproteína A-I/metabolismo , Transporte Biológico/efectos de los fármacos , Glucemia/análisis , Línea Celular , Colesterol/sangre , HDL-Colesterol/sangre , Diseño de Fármacos , Ayuno , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Hiperinsulinismo/sangre , Hiperinsulinismo/tratamiento farmacológico , Hiperinsulinismo/metabolismo , Insulina/sangre , Resistencia a la Insulina , Mucosa Intestinal/metabolismo , Intestinos/citología , Intestinos/efectos de los fármacos , Macaca mulatta , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Enfermedades Metabólicas/sangre , Enfermedades Metabólicas/tratamiento farmacológico , Enfermedades Metabólicas/metabolismo , Obesidad/sangre , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Especificidad por Sustrato , Tiazoles/farmacología , Tiazoles/uso terapéutico , Factores de Transcripción/metabolismo , Triglicéridos/sangre
16.
Mol Cell ; 6(3): 517-26, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11030332

RESUMEN

Bile acids repress the transcription of cytochrome P450 7A1 (CYP7A1), which catalyzes the rate-limiting step in bile acid biosynthesis. Although bile acids activate the farnesoid X receptor (FXR), the mechanism underlying bile acid-mediated repression of CYP7A1 remained unclear. We have used a potent, nonsteroidal FXR ligand to show that FXR induces expression of small heterodimer partner 1 (SHP-1), an atypical member of the nuclear receptor family that lacks a DNA-binding domain. SHP-1 represses expression of CYP7A1 by inhibiting the activity of liver receptor homolog 1 (LRH-1), an orphan nuclear receptor that is known to regulate CYP7A1 expression positively. This bile acid-activated regulatory cascade provides a molecular basis for the coordinate suppression of CYP7A1 and other genes involved in bile acid biosynthesis.


Asunto(s)
Ácidos y Sales Biliares/biosíntesis , Proteínas de Unión al ADN/metabolismo , Proteínas Tirosina Fosfatasas/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Factores de Transcripción/metabolismo , Animales , Northern Blotting , Células Cultivadas , Colesterol 7-alfa-Hidroxilasa/genética , Colesterol 7-alfa-Hidroxilasa/metabolismo , Proteínas de Unión al ADN/genética , Regulación Enzimológica de la Expresión Génica/fisiología , Hepatocitos/citología , Hepatocitos/enzimología , Humanos , Péptidos y Proteínas de Señalización Intracelular , Masculino , Regiones Promotoras Genéticas/fisiología , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Proteína Tirosina Fosfatasa no Receptora Tipo 6 , Proteínas Tirosina Fosfatasas/genética , ARN Mensajero/análisis , Ratas , Ratas Endogámicas F344 , Receptores Citoplasmáticos y Nucleares/genética , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Factores de Transcripción/genética , Transfección
17.
Br J Anaesth ; 85(2): 238-41, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10992831

RESUMEN

The effects of needle bevel orientation and cerebrospinal fluid (CSF) pressure on dural displacement and force required to penetrate cadaveric dura were studied using 40 samples. A constant hydrostatic pressure was applied to the subdural surface, either high or low, simulating the sitting and lateral positions. A 17-gauge Tuohy needle was advanced through the dura with the bevel oriented parallel or perpendicular to dural fibres. Travel distance and peak force at which dural penetration occurred were measured under both pressure conditions. The work required to produce dural penetration was calculated. Greater force and work were required to penetrate dura in the perpendicular orientation (P < 0.05), regardless of the subdural pressure exerted. Dural displacement was similar under both pressure conditions.


Asunto(s)
Presión del Líquido Cefalorraquídeo/fisiología , Duramadre/anatomía & histología , Agujas , Punción Espinal/instrumentación , Adulto , Anciano , Cadáver , Humanos , Presión Hidrostática , Inyecciones Epidurales/métodos , Persona de Mediana Edad , Postura
18.
Br J Anaesth ; 85(2): 305-7, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10992843

RESUMEN

We compared the pungency and tolerability of three inhaled anaesthetics in a randomized, double-blind study. Eighty-one unpremedicated patients (n = 27, each group) inhaled 2 MAC of isoflurane (2.3%), desflurane (12%) or sevoflurane (4%) for 60 s from an anaesthetic breathing circuit via a mask. Two blinded observers recorded coughing, complaints of burning and irritation, and how long the inhalation was tolerated. One sevoflurane patient coughed, but completed the study period, whereas 11 isoflurane patients and 20 desflurane patients coughed, objected verbally or removed the mask forcefully. All sevoflurane, 20 isoflurane and seven desflurane patients completed the study period (average 60, 49 and 33 s, respectively, P < 0.05). The irritability grading was: desflurane > isoflurane > sevoflurane (P < 0.05). Sevoflurane is the least irritating agent for inhalation at 2 MAC concentration.


Asunto(s)
Anestesia por Circuito Cerrado , Anestésicos por Inhalación/efectos adversos , Isoflurano/análogos & derivados , Isoflurano/efectos adversos , Éteres Metílicos/efectos adversos , Desflurano , Método Doble Ciego , Humanos , Masculino , Satisfacción del Paciente , Sevoflurano , Factores de Tiempo
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