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1.
Neurobiol Dis ; 181: 106128, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37075948

RESUMEN

RGS14 is a complex multifunctional scaffolding protein that is highly enriched within pyramidal cells (PCs) of hippocampal area CA2. In these neurons, RGS14 suppresses glutamate-induced calcium influx and related G protein and ERK signaling in dendritic spines to restrain postsynaptic signaling and plasticity. Previous findings show that, unlike PCs of hippocampal areas CA1 and CA3, CA2 PCs are resistant to a number of neurological insults, including degeneration caused by temporal lobe epilepsy (TLE). While RGS14 is protective against peripheral injury, similar roles for RGS14 during pathological injury in hippocampus remain unexplored. Recent studies showed that area CA2 modulates hippocampal excitability, generates epileptiform activity and promotes hippocampal pathology in animal models and patients with TLE. Because RGS14 suppresses CA2 excitability and signaling, we hypothesized that RGS14 would moderate seizure behavior and early hippocampal pathology following seizure activity, possibly affording protection to CA2 PCs. Using kainic acid (KA) to induce status epilepticus (KA-SE) in mice, we show that the loss of RGS14 (RGS14 KO) accelerated onset of limbic motor seizures and mortality compared to wild type (WT) mice, and that KA-SE upregulated RGS14 protein expression in CA2 and CA1 PCs of WT. Our proteomics data show that the loss of RGS14 impacted the expression of a number of proteins at baseline and after KA-SE, many of which associated unexpectedly with mitochondrial function and oxidative stress. RGS14 was shown to localize to the mitochondria in CA2 PCs of mice and reduce mitochondrial respiration in vitro. As a readout of oxidative stress, we found that RGS14 KO dramatically increased 3- nitrotyrosine levels in CA2 PCs, which was greatly exacerbated following KA-SE and correlated with a lack of superoxide dismutase 2 (SOD2) induction. Assessing for hallmarks of seizure pathology in RGS14 KO, we unexpectedly found no differences in neuronal injury in CA2 PCs. However, we observed a striking and surprising lack of microgliosis in CA1 and CA2 of RGS14 KO compared to WT. Together, our data demonstrate a newly appreciated role for RGS14 in limiting intense seizure activity and pathology in hippocampus. Our findings are consistent with a model where RGS14 limits seizure onset and mortality and, after seizure, is upregulated to support mitochondrial function, prevent oxidative stress in CA2 PCs, and promote microglial activation in hippocampus.


Asunto(s)
Epilepsia del Lóbulo Temporal , Proteínas RGS , Estado Epiléptico , Animales , Ratones , Hipocampo/metabolismo , Convulsiones , Células Piramidales/metabolismo , Epilepsia del Lóbulo Temporal/metabolismo , Estrés Oxidativo , Ácido Kaínico/toxicidad , Proteínas RGS/efectos adversos , Proteínas RGS/metabolismo
2.
BMC Cancer ; 18(1): 1016, 2018 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-30348128

RESUMEN

BACKGROUND: The Insulin-like growth factor (IGF) pathway plays a role in tumour development and progression. In vivo, IGF1 activity is regulated by the IGF binding proteins (IGFBPs). IGFBP4 inhibits the activity of IGF1 but proteolytic cleavage by pregnancy-associated plasma protein-A (PAPP-A) releases active IGF1. A modified IGFBP4, dBP4, which was resistant to PAPP-A cleavage but retained IGF1 binding capacity, was engineered, expressed in Human Embryonic Kidney (HEK) 293 cells and purified. This study examined the effects of dBP4 on IGF1-induced cell migration, invasion and angiogenesis in vitro. The effect of intra-tumour injections of dBP4 on tumour angiogenesis and metastasis was examined using the 4T1.2luc orthotopic model of breast cancer. METHODS: PAPP-A resistance and IGF binding capacity of dBP4 were characterized by Western blot and surface plasmon resonance, respectively. 4T1.2luc are mouse mammary adenocarcinoma cells transfected with luciferase to allow in vivo imaging. The effect of dBP4 on IGF1-induced Akt activation in 4T1.2luc cells was assessed by Western blot. Cell migration and invasion assays were performed using 4T1.2luc cells. Angiokit™ assays and Matrigel® implants were used to assess the effects of dBP4 on angiogenesis in vitro and in vivo, respectively. An orthotopic breast cancer model - 4T1.2luc cells implanted in the mammary fat pad of BALB/c mice - was used to assess the effect of intra tumour injection of purified dBP4 on tumour angiogenesis and metastasis. Tumour growth and lung metastasis were examined by in vivo imaging and tumour angiogenesis was evaluated by CD31 immunohistochemistry. RESULTS: Our engineered, PAPP-A resistant IGFBP4 (dBP4) retained IGF1 binding capacity and inhibited IGF1 activation of Akt as well as IGF1-induced migration and invasion by 4T1.2 mammary adenocarcinoma cells. dBP4 inhibited IGF1-induced angiogenesis in vitro and in Matrigel implants in vivo. Direct intra-tumour injection of soluble dBP4 reduced angiogenesis in 4T1.2 luc mammary tumours tumour and reduced lung metastasis. CONCLUSION: A PAPP-A resistant IGFBP4, dBP4, inhibits angiogenesis and metastasis in 4T1.2 mammary fat pad tumours. This study highlights the therapeutic potential of dBP4 as an approach to block the tumour-promoting actions of IGF1.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Proteína 4 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Neovascularización Patológica/metabolismo , Proteína Plasmática A Asociada al Embarazo/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunohistoquímica , Factor I del Crecimiento Similar a la Insulina/metabolismo , Ratones , Metástasis de la Neoplasia , Fosforilación , Proteolisis , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Recombinantes
3.
eNeuro ; 11(3)2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38514185

RESUMEN

The internal globus pallidus (GPi) is a major source of tonic GABAergic inhibition to the motor thalamus. In parkinsonism, the firing rate of GPi neurons is increased, and their pattern switches from a tonic to a burst mode, two pathophysiological changes associated with increased GABAergic pallidothalamic activity. In this study, we used high-resolution 3D electron microscopy to demonstrate that GPi terminals in the parvocellular ventral anterior nucleus (VApc) and the centromedian nucleus (CM), the two main GPi-recipient motor thalamic nuclei in monkeys, undergo significant morphometric changes in parkinsonian monkeys including (1) increased terminal volume in both nuclei; (2) increased surface area of synapses in both nuclei; (3) increased number of synapses/GPi terminals in the CM, but not VApc; and (4) increased total volume, but not number, of mitochondria/terminals in both nuclei. In contrast to GPi terminals, the ultrastructure of putative GABAergic nonpallidal terminals was not affected. Our results also revealed striking morphological differences in terminal volume, number/area of synapses, and volume/number of mitochondria between GPi terminals in VApc and CM of control monkeys. In conclusion, GABAergic pallidothalamic terminals are endowed with a high level of structural plasticity that may contribute to the development and maintenance of the abnormal increase in pallidal GABAergic outflow to the thalamus in the parkinsonian state. Furthermore, the evidence for ultrastructural differences between GPi terminals in VApc and CM suggests that morphologically distinct pallidothalamic terminals from single pallidal neurons may underlie specific physiological properties of pallidal inputs to VApc and CM in normal and diseased states.


Asunto(s)
Electrones , Núcleos Talámicos Intralaminares , Neuronas/fisiología , Globo Pálido , Microscopía Electrónica
4.
J Neurophysiol ; 110(12): 2792-805, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24068758

RESUMEN

Numerous studies have suggested that alpha-synuclein plays a prominent role in both familial and idiopathic Parkinson's disease (PD). Mice in which human alpha-synuclein is overexpressed (ASO) display progressive motor deficits and many nonmotor features of PD. However, it is unclear what in vivo pathophysiological mechanisms drive these motor deficits. It is also unknown whether previously proposed pathophysiological features (i.e., increased beta oscillations, bursting, and synchronization) described in toxin-based, nigrostriatal dopamine-depletion models are also present in ASO mice. To address these issues, we first confirmed that 5- to 6-mo-old ASO mice have robust motor dysfunction, despite the absence of significant nigrostriatal dopamine degeneration. In the same animals, we then recorded simultaneous single units and local field potentials (LFPs) in the substantia nigra pars reticulata (SNpr), the main basal ganglia output nucleus, and one of its main thalamic targets, the ventromedial nucleus, as well as LFPs in the primary motor cortex in anesthetized ASO mice and their age-matched, wild-type littermates. Neural activity was examined during slow wave activity and desynchronized cortical states, as previously described in 6-hydroxydopamine-lesioned rats. In contrast to toxin-based models, we found a small decrease, rather than an increase, in beta oscillations in the desynchronized state. Similarly, synchronized burst firing of nigral neurons observed in toxin-based models was not observed in ASO mice. Instead, we found more subtle changes in pauses of SNpr firing compared with wild-type control mice. Our results suggest that the pathophysiology underlying motor dysfunction in ASO mice is distinctly different from striatal dopamine-depletion models of parkinsonism.


Asunto(s)
Ritmo beta , Neuronas/fisiología , Enfermedad de Parkinson Secundaria/fisiopatología , Enfermedad de Parkinson/fisiopatología , Sustancia Negra/fisiopatología , Tálamo/fisiopatología , alfa-Sinucleína/genética , Potenciales de Acción , Animales , Humanos , Masculino , Ratones , Corteza Motora/fisiopatología , Neuronas/metabolismo , Oxidopamina/toxicidad , Enfermedad de Parkinson/genética , Enfermedad de Parkinson Secundaria/inducido químicamente , Sustancia Negra/citología , Sustancia Negra/metabolismo , Tálamo/citología , Tálamo/metabolismo , alfa-Sinucleína/metabolismo
5.
Ethn Health ; 18(2): 152-67, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22943791

RESUMEN

OBJECTIVES: Developing community-based and culturally congruent weight loss maintenance programs is an important component of weight reduction interventions in high-risk populations. This qualitative investigation was conducted to guide development of faith-based weight maintenance programs for African American church members. DESIGN: Twenty African American church members who previously participated in a church-based group weight loss program were recruited to participate in focus groups. This qualitative inquiry focused on the role of faith in maintaining healthy lifestyle behaviors, such as healthy eating and regular physical activity. Within these groups, a nominal group process was used to identify activities and language to be included within a faith-based maintenance program. RESULTS: Content analysis identified seven conceptual domains that participants thought were important aspects of a faith-based weight maintenance program: (1) accountability for change targets, (2) programmatic tools, (3) group benefits and support, (4) keys to successful behavior change, (5) keys to church and programmatic level success, (6) addressing barriers, and (7) faith. The faith sub-domains included faith in the Lord, using the body for God, and a spiritual focus. The nominal group process resulted in 11 recommended components for a faith-based weight maintenance program. The top four included scriptures and prayers are 'walk of faith,' healthy diet, exercise, and focusing on God. CONCLUSIONS: The results suggest that integrating faith themes into a weight loss maintenance program may increase its long-term impact on participants' health behavior change.


Asunto(s)
Negro o Afroamericano , Competencia Cultural , Promoción de la Salud/organización & administración , Desarrollo de Programa/métodos , Religión , Aumento de Peso , Anciano , Femenino , Grupos Focales , Humanos , Masculino , Persona de Mediana Edad , Conducta de Reducción del Riesgo , Estados Unidos
6.
Br J Anaesth ; 108(2): 308-15, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22157954

RESUMEN

BACKGROUND: Parallel-walled spinal needles ≤ 22 G are routinely used for lumbar puncture, despite a reported ≥ 32% incidence of post-dural puncture headache. A tapered spinal needle (22 G shaft, 27 G tip) is in use in our institution. We hypothesized that despite the smaller dural puncture hole, this needle has similar cerebrospinal fluid (CSF) pressure equilibration times and CSF sampling times to a standard 22 G needle and assessed a range of spinal needles using an experimental pulsatile CSF reservoir. METHODS: The pulsatile CSF reservoir had an oscillating pressure varying between 25 and 15 cm H(2)O at a cycle frequency of 80 s(-1). We tested seven parallel-walled spinal needles (18-27 G) and the tapered 22/27 G needle. CSF pressure was measured every 2 s by manometry. The time to collect 1 ml CSF samples was measured. Saline 0.9% and mannitol 20% were tested separately. One-way ANOVA with Bonferroni post-hoc test was used to compare 22G, 27G and 22/27G needles. RESULTS: The mean [standard deviation (sd)] CSF pressure equilibration time (saline) was 40.7 (6.4), 108.7 (6.1), and 51.3 (4.6) s for the 22, 27, and 22/27 G needles (P< 0.0001 for comparisons between 27 G and other needles). The mean (sd) CSF sampling time (saline) was 40.3 (3.1), 225.3 (10.0), and 63.0 (5.2) s for the 22, 27, and 22/27 G needles (P< 0.0001 for comparisons between 27 G and other needles, and P= 0.019 between 22 and 22/27 G needles). Saline was different from mannitol for both measurements and all needles (P< 0.0001). CONCLUSIONS: A 22/27 G tapered spinal needle has similar flow properties to the 22 G needle, despite a 27 G tip.


Asunto(s)
Presión del Líquido Cefalorraquídeo/fisiología , Modelos Neurológicos , Agujas , Punción Espinal/instrumentación , Niño , Diseño de Equipo , Humanos , Manometría/métodos , Agujas/efectos adversos , Cefalea Pospunción de la Duramadre/etiología , Cefalea Pospunción de la Duramadre/prevención & control , Flujo Pulsátil/fisiología , Reología , Punción Espinal/efectos adversos , Punción Espinal/métodos
7.
Phys Rev Lett ; 105(11): 116802, 2010 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-20867594

RESUMEN

The unusual optoelectronic properties of chalcopyrite grain boundaries (GBs) have become the subject of an intense debate in recent years. In this work we investigate the defect density at GBs of Cu(In,Ga)Se2 by scanning tunneling spectroscopy. Contrary to our expectation, our results give evidence for a reduced density of deep level defects and point to an increased density of defect levels in resonance with the lower conduction band at GBs. Our findings imply low recombination activity at GBs, and thus can explain the low impact of GBs on the efficiency of chalcopyrite based solar cells.

8.
Ann R Coll Surg Engl ; 102(3): e60-e62, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31660769

RESUMEN

Transurethral resection of the prostate (TURP) is considered the gold-standard operation to treat lower urinary tract symptoms due to benign prostatic enlargement in men. Postoperative bleeding is a recognised complication and managing it is a core skill required by attending urologists. We report a rare case of postoperative bleeding caused by fistulating vessels to the prostate which developed after TURP. These fistulas arose from the right internal iliac vessels and communicated with pre-existing pelvic varices affecting the right paraprostaticand seminal vesicle tissues. The fistulating vessels were successfully embolised with liquid embolic agent. Surgeons should be aware that persisting haemorrhage can occur post-TURP from the rare presence of fistulating vessels communicating with pelvic varices. Early computed tomography angiographic assessment is warranted in cases where bleeding is prolonged and refractory to standard management in view of timely referral for percutaneous embolisation.


Asunto(s)
Embolización Terapéutica , Fístula/terapia , Hemorragia Posoperatoria/terapia , Próstata/irrigación sanguínea , Resección Transuretral de la Próstata/efectos adversos , Várices/terapia , Anciano , Fístula/complicaciones , Hematuria/etiología , Hematuria/terapia , Humanos , Masculino , Hemorragia Posoperatoria/etiología , Prostatismo/cirugía , Várices/complicaciones
9.
Neuroscience ; 158(4): 1530-40, 2009 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-19068224

RESUMEN

Electrophysiological and pharmacological studies have demonstrated that alpha-1 adrenergic receptor (alpha1AR) activation facilitates dopamine (DA) transmission in the striatum and ventral midbrain. However, because little is known about the localization of alpha1ARs in dopaminergic regions, the substrate(s) and mechanism(s) underlying this facilitation of DA signaling are poorly understood. To address this issue, we used light and electron microscopy immunoperoxidase labeling to examine the cellular and ultrastructural distribution of alpha1ARs in the caudate putamen, nucleus accumbens, ventral tegmental area, and substantia nigra in the rat. Analysis at the light microscopic level revealed alpha1AR immunoreactivity mainly in neuropil, with occasional staining in cell bodies. At the electron microscopic level, alpha1AR immunoreactivity was found primarily in presynaptic elements, with scarce postsynaptic labeling. Unmyelinated axons and about 30-50% terminals forming asymmetric synapses contained the majority of presynaptic labeling in the striatum and midbrain, while in the midbrain a subset of terminals forming symmetric synapses also displayed immunoreactivity. Postsynaptic labeling was scarce in both striatal and ventral midbrain regions. On the other hand, only 3-6% of spines displayed alpha1AR immunoreactivity in the caudate putamen and nucleus accumbens. These data suggest that the facilitation of dopaminergic transmission by alpha1ARs in the mesostriatal system is probably achieved primarily by pre-synaptic regulation of glutamate and GABA release.


Asunto(s)
Cuerpo Estriado/metabolismo , Cuerpo Estriado/ultraestructura , Mesencéfalo/metabolismo , Mesencéfalo/ultraestructura , Microscopía Inmunoelectrónica/métodos , Receptores Adrenérgicos alfa 1/metabolismo , Animales , Masculino , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos alfa 1/ultraestructura , Sinapsis/metabolismo , Sinapsis/ultraestructura
10.
Science ; 293(5528): 311-5, 2001 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-11452128

RESUMEN

The endogenous opioid system is involved in stress responses, in the regulation of the experience of pain, and in the action of analgesic opiate drugs. We examined the function of the opioid system and mu-opioid receptors in the brains of healthy human subjects undergoing sustained pain. Sustained pain induced the regional release of endogenous opioids interacting with mu-opioid receptors in a number of cortical and subcortical brain regions. The activation of the mu-opioid receptor system was associated with reductions in the sensory and affective ratings of the pain experience, with distinct neuroanatomical involvements. These data demonstrate the central role of the mu-opioid receptors and their endogenous ligands in the regulation of sensory and affective components of the pain experience.


Asunto(s)
Encéfalo/fisiología , Fentanilo/análogos & derivados , Dolor , Receptores Opioides mu/fisiología , Adulto , Amígdala del Cerebelo/fisiología , Analgésicos Opioides/administración & dosificación , Mapeo Encefálico , Femenino , Fentanilo/administración & dosificación , Humanos , Imagen por Resonancia Magnética , Masculino , Músculo Masetero , Péptidos Opioides/fisiología , Dimensión del Dolor , Tálamo/fisiología , Tomografía Computarizada de Emisión
11.
Toxicology ; 421: 59-73, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-31059758

RESUMEN

Mono(2-ethylhexyl) phthalate (MEHP), the main di(2-ethylhexyl) phthalate (DEHP) metabolite, is a known reproductive toxicant. Residual levels of 20 nM MEHP have been found in follicular fluid aspirated from IVF-treated women and DEHP-treated animals. The current study examined whether these residual MEHP levels have any effect on the follicle-enclosed oocyte or developing embryo. Bovine oocytes were matured with or without 20 nM MEHP for 22 h. Microarray analysis was performed for both mature oocytes and 7-day blastocysts. A proteomic analysis was performed on mature oocytes (n = 200/group) to reveal a possible direct effect on the oocyte proteomic profile. Transcriptome analysis revealed MEHP-induced alterations in the expression of 456 and 290 genes in oocytes and blastocysts, respectively. The differentially expressed genes are known to be involved in various biological pathways, such as transcription process, cytoskeleton regulation and metabolic pathway. Among these, the expression of 9 genes was impaired in both oocytes exposed to MEHP (i.e., direct effect) and blastocysts developed from those oocytes (i.e., carryover effect). In addition, 191 proteins were found to be affected by MEHP in mature oocytes (Data are available via ProteomeXchange with identifier PXD012092). The study explores, for the first time, the risk associated with exposing oocytes to low concentration (i.e., environmentally relevant concentration) of MEHP to the maternal transcripts. Although it was the oocytes that were exposed to MEHP, alterations carried over to the blastocyst stage, following embryonic genome activation, implying that these embryos are of low quality.


Asunto(s)
Blastocisto/efectos de los fármacos , Dietilhexil Ftalato/análogos & derivados , Oocitos/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Animales , Blastocisto/metabolismo , Bovinos , Células Cultivadas , Dietilhexil Ftalato/toxicidad , Desarrollo Embrionario/efectos de los fármacos , Femenino , Oocitos/crecimiento & desarrollo , Oocitos/metabolismo , Proteómica
12.
Neuroscience ; 154(2): 653-66, 2008 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-18479833

RESUMEN

There is significant pharmacological and behavioral evidence that group I metabotropic glutamate receptors (mGluR1a and mGluR5) in the nucleus accumbens play an important role in the neurochemical and pathophysiological mechanisms that underlie addiction to psychostimulants. To further address this issue, we undertook a detailed ultrastructural analysis to characterize changes in the subcellular and subsynaptic localization of mGluR1a and mGluR5 in the core and shell of nucleus accumbens following acute or chronic cocaine administration in rats. After a single cocaine injection (30 mg/kg) and 45 min withdrawal, there was a significant decrease in the proportion of plasma membrane-bound mGluR1a in accumbens shell dendrites. Similarly, the proportion of plasma membrane-bound mGluR1a was decreased in large dendrites of accumbens core neurons following chronic cocaine exposure (i.e. 1-week treatment followed by 3-week withdrawal). However, neither acute nor chronic cocaine treatments induced significant change in the localization of mGluR5 in accumbens core and shell, which is in contrast with the significant reduction of plasma membrane-bound mGluR1a and mGluR5 induced by local intra-accumbens administration of the group I mGluR agonist, (RS)-3,5-dihydroxyphenylglycine (DHPG). In conclusion, these findings demonstrate that cocaine-induced glutamate imbalance has modest effects on the trafficking of group I mGluRs in the nucleus accumbens. These results provide valuable information on the neuroadaptive mechanisms of accumbens group I mGluRs in response to cocaine administration.


Asunto(s)
Cocaína/farmacología , Núcleo Accumbens/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Fracciones Subcelulares/metabolismo , Sinapsis/metabolismo , Animales , Agonistas de Aminoácidos Excitadores/farmacología , Técnicas para Inmunoenzimas , Inmunohistoquímica , Masculino , Metoxihidroxifenilglicol/administración & dosificación , Metoxihidroxifenilglicol/análogos & derivados , Metoxihidroxifenilglicol/farmacología , Microscopía Inmunoelectrónica , Núcleo Accumbens/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptor del Glutamato Metabotropico 5 , Receptores de Glutamato Metabotrópico/administración & dosificación , Receptores de Glutamato Metabotrópico/genética , Fracciones Subcelulares/efectos de los fármacos
13.
Neuroscience ; 154(1): 99-113, 2008 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-18222048

RESUMEN

In nonprimate mammals, the dorsal cochlear nucleus (DCN) is thought to play a role in the orientation of the head toward sounds of interest by integrating acoustic and somatosensory information. Humans and higher primates might not use this system because of reported phylogenetic changes in DCN cytoarchitecture [Moskowitz N (1969) Comparative aspects of some features of the central auditory system of primates. Ann N Y Acad Sci 167:357-369; Moore JK, Osen KK (1979) The cochlear nuclei in man. Am J Anat 154:393-418; Moore JK (1980) The primate cochlear nuclei: loss of lamination as a phylogenetic process. J Comp Neurol 193:609-629]. In this study, we re-evaluated this question from a comparative perspective and examined the rhesus monkey (cercopithecoid primate) using more sensitive probes and higher resolution imaging methods. We used electron microscopy to identify parallel fibers and their synapses, and molecular markers to determine that primates exhibit the main components of excitatory neurotransmission as other mammals. We observed that characteristics of the monkey molecular layer resembled what has been reported for nonprimates: (1) immunohistochemistry revealed many unmyelinated, thin axons and en passant glutamatergic synapses on dendritic spines; (2) immunohistochemistry for phosphodiesterase (PDE10A) showed the nuclei of granule cells distributed in the external molecular layer and the deep layers in the DCN; (3) antibodies for the inositol trisphosphate receptor (IP3r) and calbindin immunostained cartwheel cells; (4) postembedding immunogold labeling revealed synaptic expression of AMPA and delta glutamate receptor subunits on spines in parallel fiber endings; and (5) parallel fibers use vesicular glutamate transporter 1 (VGLUT1) to package glutamate into the synaptic vesicles and to mediate glutamate transport. These observations are consistent with the argument that the rhesus monkey DCN has neuronal features similar to those of other nonprimate mammals.


Asunto(s)
Núcleo Coclear/citología , Neuronas/metabolismo , Neuronas/ultraestructura , Animales , Calbindinas , Núcleo Coclear/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Macaca mulatta , Microscopía Electrónica de Transmisión/métodos , Microscopía Inmunoelectrónica/métodos , Hidrolasas Diéster Fosfóricas/metabolismo , Terminales Presinápticos/metabolismo , Terminales Presinápticos/ultraestructura , Receptores AMPA/metabolismo , Receptores AMPA/ultraestructura , Proteína G de Unión al Calcio S100/metabolismo , Sinapsis/metabolismo , Sinapsis/ultraestructura , Proteína 1 de Transporte Vesicular de Glutamato/metabolismo
14.
Neuroscience ; 151(4): 969-82, 2008 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-18248908

RESUMEN

Members of the regulator of G protein signaling 7 (RGS7) (R7) family and Gbeta5 form obligate heterodimers that are expressed predominantly in the nervous system. R7-Gbeta5 heterodimers are GTPase-activating proteins (GAPs) specific for Gi/o-class Galpha subunits, which mediate phototransduction in retina and the action of many modulatory G protein-coupled receptors (GPCRs) in brain. Here we have focused on the R7-family binding protein (R7BP), a recently identified palmitoylated protein that can bind R7-Gbeta5 complexes and is hypothesized to control the intracellular localization and function of the resultant heterotrimeric complexes. We show that: 1) R7-Gbeta5 complexes are obligate binding partners for R7BP in brain because they co-immunoprecipitate and exhibit similar expression patterns. Furthermore, R7BP and R7 protein accumulation in vivo requires Gbeta5. 2) Expression of R7BP in Neuro2A cells at levels approximating those in brain recruits endogenous RGS7-Gbeta5 complexes to the plasma membrane. 3) R7BP immunoreactivity in brain concentrates in neuronal soma, dendrites, spines or unmyelinated axons, and is absent or low in glia, myelinated axons, or axon terminals. 4) RGS7-Gbeta5-R7BP complexes in brain extracts associate inefficiently with detergent-resistant lipid raft fractions with or without G protein activation. 5) R7BP and Gbeta5 protein levels are upregulated strikingly during the first 2-3 weeks of postnatal brain development. Accordingly, we suggest that R7-Gbeta5-R7BP complexes in the mouse or rat could regulate signaling by modulatory Gi/o-coupled GPCRs in the developing and adult nervous systems.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Subunidades beta de la Proteína de Unión al GTP/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteínas RGS/metabolismo , Animales , Animales Recién Nacidos , Encéfalo/ultraestructura , Células Cultivadas , Subunidades beta de la Proteína de Unión al GTP/deficiencia , Inmunoprecipitación/métodos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Microscopía Inmunoelectrónica/métodos , Neuronas/metabolismo , Neuronas/ultraestructura , Unión Proteica/fisiología , Ratas , Ratas Sprague-Dawley
15.
Int J STD AIDS ; 19(2): 77-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18334056

RESUMEN

At a time of high capacity almost 40% of patients declined an appointment within 48 hours. Data were collected prospectively on the reasons why, and the impact of demand exceeding capacity.


Asunto(s)
Citas y Horarios , Accesibilidad a los Servicios de Salud , Venereología , Adulto , Femenino , Necesidades y Demandas de Servicios de Salud , Humanos , Masculino , Servicio Ambulatorio en Hospital , Estudios Prospectivos
16.
J Public Health Manag Pract ; 14(1): 29-32, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18091037

RESUMEN

AIM: The purpose of this study was to translate the National Institutes of Health (NIH)-Diabetes Prevention Program (DPP) into a church-based setting. METHODS: The lifestyle arm of the NIH-DPP was implemented in an African American Baptist church. Church members 18 years or older completed a risk screen during Sunday service followed by fasting glucose (FG) testing at the church during the week. Persons with prediabetes participated in a 16-session DPP conducted over 4 months. Participation rates, height, weight, blood pressure (BP) and FG were followed for 12 months post-intervention. Fifty participants completed the risk screen, 26 were at risk for diabetes, 16 of 26 received FG testing, and 8 had prediabetes (FG = 100- 125 mg/dL). RESULTS: The mean participation rate was 10.4 (65%) sessions. Following the intervention, weight, systolic and diastolic BP, and FG decreased by 7.5 lb (3.6%), 16 mm Hg (11.7%), 12 mm Hg (14.0%), and 5 mg/dL (4.8%), respectively (P < .05). In comparison with baseline, significant reductions were evident at 6 and 12 months postintervention for all endpoints. CONCLUSIONS: This study demonstrated successful translation of the 16-session NIH-DPP into a church-based setting. Future studies should test this intervention in churches of different sizes and denominations.


Asunto(s)
Negro o Afroamericano , Diabetes Mellitus Tipo 2/etnología , Diabetes Mellitus Tipo 2/prevención & control , Promoción de la Salud/organización & administración , Tamizaje Masivo/organización & administración , Estado Prediabético/diagnóstico , Protestantismo , Religión y Medicina , Adulto , Ejercicio Físico/fisiología , Femenino , Prueba de Tolerancia a la Glucosa , Promoción de la Salud/métodos , Humanos , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad , National Institutes of Health (U.S.) , Proyectos Piloto , Estado Prediabético/etnología , Evaluación de Programas y Proyectos de Salud , Sudeste de Estados Unidos , Estados Unidos/epidemiología , Salud Urbana , Pérdida de Peso/fisiología
17.
Paleoceanogr Paleoclimatol ; 33(3): 318-335, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31058258

RESUMEN

The Arctic cryosphere is changing and making a significant contribution to sea level rise. The Late Pliocene had similar CO2 levels to the present and a warming comparable to model predictions for the end of this century. However, the state of the Arctic cryosphere during the Pliocene remains poorly constrained. For the first time we combine outputs from a climate model with a thermodynamic iceberg model to simulate likely source regions for ice-rafted debris (IRD) found in the Nordic Seas from Marine Isotope Stage M2 to the mid-Piacenzian Warm Period and what this implies about the nature of the Arctic cryosphere at this time. We compare the fraction of melt given by the model scenarios with IRD data from four Ocean Drilling Program sites in the Nordic Seas. Sites 911A, 909C, and 907A show a persistent occurrence of IRD that model results suggest is consistent with permanent ice on Svalbard. Our results indicate that icebergs sourced from the east coast of Greenland do not reach the Nordic Seas sites during the warm Late Pliocene but instead travel south into the North Atlantic. In conclusion, we suggest a continuous occurrence of marine-terminating glaciers on Svalbard and on East Greenland (due to the elevation of the East Greenland Mountains during the Late Pliocene). The study has highlighted the usefulness of coupled climate model-iceberg trajectory modeling for understanding ice sheet behavior when proximal geological records for Pliocene ice presence or absence are absent or are inconclusive.

18.
Neuroscience ; 149(2): 338-49, 2007 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-17881134

RESUMEN

The globus pallidus (GP) plays a central integrative role in the basal ganglia circuitry. It receives strong GABAergic inputs from the striatum (Str) and significant glutamatergic afferents from the subthalamic nucleus (STN). The change in firing rate and pattern of GP neurons is a cardinal feature of Parkinson's disease pathophysiology. Kainate receptor (KAR) GluR6/7 subunit immunoreactivity is expressed presynaptically in GABAergic striatopallidal terminals which provides a substrate for regulation of GABAergic transmission in GP. To test this hypothesis, we recorded GABA(A)-mediated inhibitory postsynaptic currents (IPSCs) in the GP following electrical stimulation of the Str. Following blockade of AMPA and N-methyl-d-aspartate receptors with selective antagonists, bath application of kainate (KA) (0.3-3 microM) reduced significantly the amplitude of evoked IPSCs. This inhibition was associated with a significant increase in paired-pulse facilitation ratio and a reduction of the frequency, but not amplitude, of miniature inhibitory postsynaptic currents (mIPSCs), suggesting a presynaptic site of KA action. The KA effects on striatopallidal GABAergic transmission were blocked by the G-protein inhibitor, N-ethylmaleimide (NEM), or protein kinase C (PKC) inhibitor calphostin C. Our results demonstrate that KAR activation inhibits GABAergic transmission through a presynaptic G protein-coupled, PKC-dependent metabotropic mechanism in the rat GP. These findings open up the possibility for the development of KA-mediated pharmacotherapies aimed at decreasing the excessive and abnormally regulated inhibition of GP neurons in Parkinson's disease.


Asunto(s)
Globo Pálido/efectos de los fármacos , Receptores de Ácido Kaínico/agonistas , Receptores Presinapticos/agonistas , Transmisión Sináptica/efectos de los fármacos , Ácido gamma-Aminobutírico/fisiología , Animales , Interpretación Estadística de Datos , Estimulación Eléctrica , Electrofisiología , Activación Enzimática/fisiología , Inhibidores Enzimáticos/farmacología , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Ácido Kaínico/farmacología , Lisina/análogos & derivados , Lisina/metabolismo , Neostriado/fisiología , Técnicas de Placa-Clamp , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C/metabolismo , Proteína Quinasa C/fisiología , Ratas , Ratas Sprague-Dawley , Sinapsis/fisiología
19.
Diabetes Res Clin Pract ; 75(1): 81-7, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16764963

RESUMEN

OBJECTIVE: To determine the impact of a simple nurse-based prompt on fasting glucose screening and counseling regarding diet, exercise and weight loss to persons at increased risk for type 2 diabetes. RESEARCH DESIGN AND METHODS: Patients at risk for diabetes were recruited from 10 primary care practices. Nurses were trained to score a diabetes risk assessment and prompt providers concerning all high-risk subjects. Both univariate and multivariate logistic regression models were used to determine the association between the nurse prompt and subsequent fasting glucose testing or receiving advice for diet, exercise, or weight loss. RESULTS: Of 1176 subjects, 597 were recruited from intervention practices and 579 from control practices. In both the univariate and multivariate models, the intervention group was more likely to receive fasting glucose testing and advice for diet, exercise and weight loss. In the multivariate model, patients in the intervention group were more likely to receive fasting glucose testing (odds ratio 9.3, 95% confidence interval 3.6-24.0), dietary advice (6.1, 3.5-10.7), exercise advice (7.4, 4.0-13.9), and weight loss advice (1.9, 1.1-3.7). CONCLUSIONS: A simple nurse-based prompt is an effective tool to increase screening and preventive services for people at risk for type 2 diabetes.


Asunto(s)
Consejo , Diabetes Mellitus/epidemiología , Diabetes Mellitus/prevención & control , Tamizaje Masivo , Enfermeras y Enfermeros , Análisis de Varianza , Educación Continua en Enfermería , Humanos , Análisis Multivariante , Factores de Riesgo
20.
J Natl Med Assoc ; 99(4): 440-6, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17444435

RESUMEN

OBJECTIVES: The purpose of this study was to determine the feasibility of implementing a diabetes prevention program (DPP) in a rural African-American church. METHODS: A six-session DPP, modeled after the successful National Institutes of Health (NIH) DPP, was implemented in a rural African-American church. Adult members of the church identified as high risk for diabetes, based on results of a risk questionnaire, were screened with a fasting glucose. Persons with prediabetes, a fasting glucose of 100-125 mg/dL, participated in the six-session, Lifestyle Balance Church DPP. The primary outcomes were attendance rates and changes in fasting glucose, weight and body mass index measured at baseline, six- and 12-month follow-up. RESULTS: Ninety-nine adult church members were screened for diabetes risk. Eleven had impaired fasting glucose. Ten of 11 participated in the six-session intervention, for an attendance rate of 78%. After the intervention and 12-month follow-up, there was a mean weight loss of 7.9 lbs and 10.6 lbs, respectively. CONCLUSIONS: This pilot project suggests that a modified six-session DPP can be translated to a group format and successfully implemented in a church setting. Further randomized studies are needed to determine the effectiveness of such an intervention.


Asunto(s)
Negro o Afroamericano/educación , Diabetes Mellitus/etnología , Diabetes Mellitus/prevención & control , Conductas Relacionadas con la Salud/etnología , Educación en Salud/organización & administración , Modelos Educacionales , Desarrollo de Programa/métodos , Religión y Medicina , Servicios de Salud Rural/organización & administración , Adolescente , Adulto , Femenino , Georgia , Humanos , Estilo de Vida , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Proyectos Piloto , Medición de Riesgo , Encuestas y Cuestionarios
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