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1.
Eur J Pharmacol ; 925: 175013, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35537491

RESUMO

QX-314 is a quaternary permanently charged lidocaine derivative that inhibits voltage-gated sodium channels (NaV). As it is membrane impermeable, it is generally considered that QX-314 applied externally is inactive, unless it can gain access to the internal local anesthetic binding site via another entry pathway. Here, we characterized the electrophysiological effects of QX-314 on NaV1.7 heterologously expressed in HEK293 cells, and found that at high concentrations, external QX-314 inhibited NaV1.7 current (IC50 2.0 ± 0.3 mM) and shifted the voltage-dependence to more depolarized potentials (ΔV50 +10.6 mV). Unlike lidocaine, the activity of external QX-314 was not state- or use-dependent. The effect of externally applied QX-314 on NaV1.7 channel biophysics differed to that of internally applied QX-314, suggesting QX-314 has an additional externally accessible site of action. In line with this hypothesis, disruption of the local anesthetic binding site in a [F1748A]NaV1.7 mutant reduced the potency of lidocaine by 40-fold, but had no effect on the potency or activity of externally applied QX-314. Therefore, we conclude, using an expression system where QX-314 was unable to cross the membrane, that externally applied QX-314 is able to inhibit NaV1.7 peak current at low millimolar concentrations.


Assuntos
Anestésicos Locais , Lidocaína , Anestésicos Locais/farmacologia , Células HEK293 , Humanos , Lidocaína/análogos & derivados , Lidocaína/farmacologia , Sódio/metabolismo , Bloqueadores dos Canais de Sódio/farmacologia
2.
AIMS Neurosci ; 9(1): 31-56, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35434279

RESUMO

Vitamin D deficiency is prevalent in adults and is associated with cognitive impairment. However, the mechanism by which adult vitamin D (AVD) deficiency affects cognitive function remains unclear. We examined spatial memory impairment in AVD-deficient BALB/c mice and its underlying mechanism by measuring spine density, long term potentiation (LTP), nitric oxide (NO), neuronal nitric oxide synthase (nNOS), and endothelial NOS (eNOS) in the hippocampus. Adult male BALB/c mice were fed a control or vitamin D deficient diet for 20 weeks. Spatial memory performance was measured using an active place avoidance (APA) task, where AVD-deficient mice had reduced latency entering the shock zone compared to controls. We characterised hippocampal spine morphology in the CA1 and dentate gyrus (DG) and made electrophysiological recordings in the hippocampus of behaviourally naïve mice to measure LTP. We next measured NO, as well as glutathione, lipid peroxidation and oxidation of protein products and quantified hippocampal immunoreactivity for nNOS and eNOS. Spine morphology analysis revealed a significant reduction in the number of mushroom spines in the CA1 dendrites but not in the DG. There was no effect of diet on LTP. However, hippocampal NO levels were depleted whereas other oxidation markers were unaltered by AVD deficiency. We also showed a reduced nNOS, but not eNOS, immunoreactivity. Finally, vitamin D supplementation for 10 weeks to AVD-deficient mice restored nNOS immunoreactivity to that seen in in control mice. Our results suggest that lower levels of NO and reduced nNOS immunostaining contribute to hippocampal-dependent spatial learning deficits in AVD-deficient mice.

3.
Front Physiol ; 12: 738594, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34621187

RESUMO

Selective SGLT2 inhibition reduces the risk of worsening heart failure and cardiovascular death in patients with existing heart failure, irrespective of diabetic status. We aimed to investigate the effects of dual SGLT1/2 inhibition, using sotagliflozin, on cardiac outcomes in normal diet (ND) and high fat diet (HFD) mice with cardiac pressure overload. Five-week-old male C57BL/6J mice were randomized to receive a HFD (60% of calories from fat) or remain on ND for 12 weeks. One week later, transverse aortic constriction (TAC) was employed to induce cardiac pressure-overload (50% increase in right:left carotid pressure versus sham surgery), resulting in left ventricular hypertrophic remodeling and cardiac fibrosis, albeit preserved ejection fraction. At 4 weeks post-TAC, mice were treated for 7 weeks by oral gavage once daily with sotagliflozin (10 mg/kg body weight) or vehicle (0.1% tween 80). In ND mice, treatment with sotagliflozin attenuated cardiac hypertrophy and histological markers of cardiac fibrosis induced by TAC. These benefits were associated with profound diuresis and glucosuria, without shifts toward whole-body fatty acid utilization, increased circulating ketones, nor increased cardiac ketolysis. In HFD mice, sotagliflozin reduced the mildly elevated glucose and insulin levels but did not attenuate cardiac injury induced by TAC. HFD mice had vacuolation of proximal tubular cells, associated with less profound sotagliflozin-induced diuresis and glucosuria, which suggests dampened drug action. We demonstrate the utility of dual SGLT1/2 inhibition in treating cardiac injury induced by pressure overload in normoglycemic mice. Its efficacy in high fat-fed mice with mild hyperglycemia and compromised renal morphology requires further study.

4.
Financ Res Lett ; 43: 101957, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36568951

RESUMO

Banks can potentially reduce the variability of their revenue by diversifying beyond traditional lending activities into noninterest revenue sources. We investigate the effect of the COVID-19 pandemic on the relation between the use of noninterest income and bank profit and risk. The economic effect of the pandemic resulted in tightened credit standards and reduced demand for many types of loans. We find that noninterest revenue sources are positively related to performance but inversely related to risk. These results are consistent with a beneficial diversification effect during the pandemic from banks expanding beyond traditional lending sources of revenue.

5.
Biomedicines ; 8(5)2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32443665

RESUMO

Conopeptides belonging to the A-superfamily from the venomous molluscs, Conus, are typically α-conotoxins. The α-conotoxins are of interest as therapeutic leads and pharmacological tools due to their selectivity and potency at nicotinic acetylcholine receptor (nAChR) subtypes. Structurally, the α-conotoxins have a consensus fold containing two conserved disulfide bonds that define the two-loop framework and brace a helical region. Here we report on a novel α-conotoxin Pl168, identified from the transcriptome of Conus planorbis, which has an unusual 4/8 loop framework. Unexpectedly, NMR determination of its three-dimensional structure reveals a new structural type of A-superfamily conotoxins with a different disulfide-stabilized fold, despite containing the conserved cysteine framework and disulfide connectivity of classical α-conotoxins. The peptide did not demonstrate activity on a range of nAChRs, or Ca2+ and Na+ channels suggesting that it might represent a new pharmacological class of conotoxins.

6.
Nephrology (Carlton) ; 25(7): 575-581, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32180312

RESUMO

AIM: The measurement of glomerular filtration rate (GFR) in experimental rodents is pivotal to understanding the progression of kidney disease and benefits of treatment strategies. A non-invasive clearance device has been developed, which measures transcutaneous decay of injected FITC-sinistrin in conscious rodents. The technique was validated against the well-established plasma clearance method in the same mice, but on consecutive days, using only models of uninephrectomy and polycystic kidney disease. We aimed to validate this widely used technique in the same lean or obese mice, at the same time. METHODS: Five-week-old male C57BL/6J mice were randomised to a high fat diet (n = 12) or normal diet (n = 11) for 10 weeks. Transcutaneous and plasma clearance of FITC-sinistrin were measured simultaneously in each mouse. RESULTS: In lean mice, there was a positive correlation between transcutaneous and plasma derived GFR (P < .01, R2 = .704), although there was an approximate 40% underestimation by the transcutaneous method (P < .0001). In obese mice, no correlation was observed between transcutaneous and plasma derived GFR, nor elimination half-life which removes any effect of the conversion factor and injected dose. The limits of agreement in a Bland-Altman plot were narrower when we used new conversion factors derived from mice in the current study and, in lean mice, a generic conversion factor which assumes 20% extracellular volume. CONCLUSION: The non-invasive clearance device may be useful for serial GFR measurements in lean and healthy mice, provided validation studies have been carried out, but its utility in obesity requires further study.


Assuntos
Peso Corporal/fisiologia , Fluoresceínas/farmacocinética , Taxa de Filtração Glomerular , Testes de Função Renal/métodos , Oligossacarídeos/farmacocinética , Doenças Renais Policísticas , Eliminação Renal , Rim Único , Animais , Técnicas de Diagnóstico Urológico/instrumentação , Dieta Hiperlipídica , Progressão da Doença , Corantes Fluorescentes/farmacocinética , Taxa de Depuração Metabólica , Camundongos , Camundongos Endogâmicos C57BL , Doenças Renais Policísticas/diagnóstico , Doenças Renais Policísticas/metabolismo , Utilização de Procedimentos e Técnicas , Reprodutibilidade dos Testes , Rim Único/diagnóstico , Rim Único/metabolismo
7.
J Pain ; 21(1-2): 182-194, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31260808

RESUMO

Vincristine, oxaliplatin, and cisplatin are commonly prescribed chemotherapeutic agents for the treatment of many tumors. However, a main side effect is chemotherapy-induced peripheral neuropathy (CIPN), which may lead to changes in chemotherapeutic treatment. Although symptoms associated with CIPN are recapitulated by mouse models, there is limited knowledge of how these drugs affect the expression of genes in sensory neurons. The present study carried out a transcriptomic analysis of dorsal root ganglia following vincristine, oxaliplatin, and cisplatin treatment with a view to gain insight into the comparative pathophysiological mechanisms of CIPN. RNA-Seq revealed 368, 295, and 256 differential expressed genes induced by treatment with vincristine, oxaliplatin, and cisplatin, respectively, and only 5 shared genes were dysregulated in all 3 groups. Cell type enrichment analysis and gene set enrichment analysis showed predominant effects on genes associated with the immune system after treatment with vincristine, while oxaliplatin treatment affected mainly neuronal genes. Treatment with cisplatin resulted in a mixed gene expression signature. PERSPECTIVE: These results provide insight into the recruitment of immune responses to dorsal root ganglia and indicate enhanced neuroinflammatory processes following administration of vincristine, oxaliplatin, and cisplatin. These gene expression signatures may provide insight into novel drug targets for treatment of CIPN.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Inflamação/induzido quimicamente , Inflamação/genética , Síndromes Neurotóxicas/genética , Oxaliplatina/toxicidade , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/genética , Transcriptoma/genética , Vincristina/toxicidade , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL
8.
Am J Physiol Regul Integr Comp Physiol ; 314(6): R858-R869, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29443547

RESUMO

There is an increased incidence of heart failure in individuals with diabetes mellitus (DM). The coexistence of kidney disease in DM exacerbates the cardiovascular prognosis. Researchers have attempted to combine the critical features of heart failure, using transverse aortic constriction, with DM in mice, but variable findings have been reported. Furthermore, kidney outcomes have not been assessed in this setting; thus its utility as a model of heart failure in DM and kidney disease is unknown. We generated a mouse model of obesity, hyperglycemia, and mild kidney pathology by feeding male C57BL/6J mice a high-fat diet (HFD). Cardiac pressure overload was surgically induced using transverse aortic constriction (TAC). Normal diet (ND) and sham controls were included. Heart failure risk factors were evident at 8-wk post-TAC, including increased left ventricular mass (+49% in ND and +35% in HFD), cardiomyocyte hypertrophy (+40% in ND and +28% in HFD), and interstitial and perivascular fibrosis (Masson's trichrome and picrosirius red positivity). High-fat feeding did not exacerbate the TAC-induced cardiac outcomes. At 11 wk post-TAC in a separate mouse cohort, echocardiography revealed reduced left ventricular size and increased left ventricular wall thickness, the latter being evident in ND mice only. Systolic function was preserved in the TAC mice and was similar between ND and HFD. Thus combined high-fat feeding and TAC in mice did not model the increased incidence of heart failure in DM patients. This model, however, may mimic the better cardiovascular prognosis seen in overweight and obese heart failure patients.


Assuntos
Aorta/fisiopatologia , Diabetes Mellitus Experimental/metabolismo , Dieta Hiperlipídica/efeitos adversos , Insuficiência Cardíaca/etiologia , Nefropatias/metabolismo , Animais , Composição Corporal , Constrição Patológica , Diabetes Mellitus Experimental/fisiopatologia , Ecocardiografia , Metabolismo Energético/fisiologia , Coração/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/patologia , Nefropatias/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/fisiologia , Miócitos Cardíacos/ultraestrutura , Fatores de Risco
9.
J Chem Neuroanat ; 82: 29-38, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28419831

RESUMO

The bed nucleus of the stria terminalis (BNST) is a complex integrative centre in the forebrain, composed of multiple sub-nuclei, each with discrete populations of neurons. Progress in understanding BNST function, both in the adult and during postnatal maturation, is dependent upon a more complete characterization of neuronal phenotypes in the BNST. The aim of the current study was to define the molecular phenotype of one postnatal BNST neuronal population, in order to identify molecular factors that may underlie both (protein marker-related) immaturity, and secondly, the transience of this phenotype. This BNST population was originally identified by high, but transient expression of the EGR1 transcription factor (TF) in postnatal rat lateral intermediate BNST (BNSTLI). The current results confirm a high level of Egr1 activation in postnatal day 10 (PN10) male BNSTLI that is lost at PN40, and now demonstrate a similar pattern of transient activation in female brains. Apparent cellular immaturity in this population, as indicated by low levels of the adult neuronal marker NeuN/RBFOX3, was found to be uncorrelated with both key neuronal regulator protein expression (SOX2 and REST), and also RBFOX2 protein levels. The BNSTLI neurons have a partial catecholaminergic phenotype (tyrosine hydroxylase-positive/dopa decarboxylase-negative; TH+ve/DDC-ve) that is lost at PN40. In contrast, the co-expressed neuropeptide, somatostatin, is maintained, albeit at lower levels, at PN40. The transcriptional basis of the transient and partial catecholaminergic phenotype was investigated by analysing TFs known to maintain adult dopaminergic (TH+ve/DDC+ve) neuronal phenotypes. The BNSTLI neurons were shown to lack forkhead TFs including FOXA1, FOXA2 and FOXO1. In addition, the BNSTLI neurons had low, primarily cytoplasmic, expression of NR4A2/NURR1, an orphan nuclear receptor that is critical for adult maintenance of midbrain dopamine neurons. These results detail the molecular features of an immature neuronal phenotype, and reveal TF deficiencies that may underlie postnatal transience of the phenotype.


Assuntos
Neurônios/química , Neurônios/enzimologia , Fenótipo , Núcleos Septais/química , Núcleos Septais/enzimologia , Tirosina 3-Mono-Oxigenase/metabolismo , Animais , Animais Recém-Nascidos , Feminino , Masculino , Ratos , Ratos Transgênicos , Tirosina 3-Mono-Oxigenase/análise , Tirosina 3-Mono-Oxigenase/genética
10.
Cureus ; 8(8): e740, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-27672531

RESUMO

The most frequently encountered complication of dorsal column stimulators is lead migration. The vast majority of these events are seen in the first few weeks to months. Late paddle lead migration is a very uncommon occurrence in this setting. We describe a case of a 51-year-old male with a history of reflex sympathetic dystrophy having undergone dorsal column stimulator insertion at the level of C1-C2. A good clinical benefit was appreciated in the postoperative period once the stimulator was turned on. Approximately six months postoperatively, the patient suddenly lost coverage. Radiographic imaging revealed that the lead had migrated caudally to the C3-C4 level. Subsequent revision surgery took place. This description highlights a common complication, but occurring outside the expected time frame after surgery.

11.
Sci Rep ; 6: 33792, 2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27653836

RESUMO

Autosomal dominant vitreoretinochoroidopathy (ADVIRC) is a rare, early-onset retinal dystrophy characterised by distinct bands of circumferential pigmentary degeneration in the peripheral retina and developmental eye defects. ADVIRC is caused by mutations in the Bestrophin1 (BEST1) gene, which encodes a transmembrane protein thought to function as an ion channel in the basolateral membrane of retinal pigment epithelial (RPE) cells. Previous studies suggest that the distinct ADVIRC phenotype results from alternative splicing of BEST1 pre-mRNA. Here, we have used induced pluripotent stem cell (iPSC) technology to investigate the effects of an ADVIRC associated BEST1 mutation (c.704T > C, p.V235A) in patient-derived iPSC-RPE. We found no evidence of alternate splicing of the BEST1 transcript in ADVIRC iPSC-RPE, however in patient-derived iPSC-RPE, BEST1 was expressed at the basolateral membrane and the apical membrane. During human eye development we show that BEST1 is expressed more abundantly in peripheral RPE compared to central RPE and is also expressed in cells of the developing retina. These results suggest that higher levels of mislocalised BEST1 expression in the periphery, from an early developmental stage, could provide a mechanism that leads to the distinct clinical phenotype observed in ADVIRC patients.

12.
World Neurosurg ; 91: 297-307, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27072332

RESUMO

INTRODUCTION: Penetrating traumatic brain injuries (TBIs), with the exception of gunshot wounds, are relatively rare occurrences and affect all ages. Clinical presentation varies depending on the mechanism of the injury. Prompt surgical treatment is often indicated and is influenced by patient clinical examination, anatomic trajectory, and the penetrating object's size, shape, and velocity. METHODS: We present 3 cases of penetrating TBI. Their similarities and differences affecting operative and medical management are compared. We relate our experience with management of penetrating intracranial foreign bodies in general and discuss the relevant literature. RESULTS: Our first case was a 12-year-old male who presented with a self-inflicted transfacial transcranial injury by a crossbow. The arrow passed through the left sphenoid and cavernous sinus and exited through the parietal calvarium. Our second case was a 37-year-old man with a transoral intracranial stab wound by a knife. In our third case, we present a 46-year-old male who accidentally fired a nail gun into his right ear. The nail traversed the posterior wall of the external auditory canal into the posterior fossa, ending in the cerebellar vermis. Each case was treated with craniotomy and foreign body removal. All resulted in good outcomes after surgical treatment. CONCLUSION: Surgery in penetrating TBI is the treatment of choice. Our cases demonstrate how certain principles applied to individual patient scenarios may optimize clinical results. Severity of the injury and operative approach are among the most important considerations to achieve the best patient outcomes.


Assuntos
Lesões Encefálicas Traumáticas/cirurgia , Traumatismos Cranianos Penetrantes/cirurgia , Ferimentos Perfurantes/cirurgia , Adulto , Angiografia Digital , Encéfalo/cirurgia , Criança , Angiografia por Tomografia Computadorizada , Craniotomia/métodos , Corpos Estranhos/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Comportamento Autodestrutivo/cirurgia , Tomografia Computadorizada por Raios X
13.
Exp Physiol ; 99(12): 1597-610, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25239924

RESUMO

Chronic low-dose systemic infusion of angiotensin II induces hypertension via activation of the angiotensin II type 1A receptor (AT1AR). Previously, we have demonstrated that expression of the AT1AR on catecholaminergic neurons is necessary for the full development of angiotensin-dependent hypertension. In the present study, we examined the mechanism by which selective deletion of the AT1AR from these cells affects the development of hypertension. We also tested the hypothesis that AT1ARs expressed by catecholaminergic C1 neurons in the rostral ventrolateral medulla play an important role in angiotensin-induced hypertension. A Cre-lox approach was used to delete the AT1AR from all catecholaminergic cells or from C1 neurons selectively. Subcutaneous administration of angiotensin II induced hypertension in all mice, with delayed onset and reduced maximal response in the global AT1AR catecholaminergic knockout mice. The AT1AR catecholaminergic knockout mice had decreased renal fluid and electrolyte retention and urinary noradrenaline excretion. The blood pressure response was reduced only during the second week of angiotensin II infusion in the mice with selective C1 AT1AR deletion, demonstrating that AT1AR expression by C1 neurons plays a moderate role in angiotensin-induced hypertension. The difference in the time course of development of hypertension between the mice with global AT1AR knockout from catecholaminergic cells and the mice with C1 AT1AR deletion suggests that other catecholaminergic neurons are important.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/metabolismo , Bulbo/metabolismo , Neurônios/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Angiotensina II , Animais , Hipertensão/induzido quimicamente , Hipertensão/genética , Camundongos , Camundongos Knockout , Receptor Tipo 1 de Angiotensina/genética
14.
J Chem Neuroanat ; 61-62: 153-60, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25263324

RESUMO

The transcription factor SOX2 has many established roles in neural development but is generally considered to have limited activity in the adult brain. As part of a study of neuronal phenotypes in the adult rodent hypothalamus, we have now used immunohistochemical analysis to investigate the expression of SOX2 in the adult rat and mouse hypothalamus. Our analysis has revealed that SOX2 protein is extensively expressed in cells of the suprachiasmatic nucleus (SCN). Co-localization with the nuclear marker proteins NeuN and MeCP2 confirmed SOX2 expression in mature neurons of the rat SCN, and the functional integrity of these SOX2+ neurons was also confirmed by demonstrating co-localization with light-induced EGR1 protein. In addition to the SCN, we have also revealed a population of SOX2+/(NeuN+/MeCP2+) neurons in the rat periventricular nucleus (PeN). However, in other hypothalamic nuclei such as the supraoptic nucleus (SON) SOX2+ cells were rare. In extra-hypothalamic areas, SOX2+ cells were also scarce although we have confirmed populations of non-neuronal SOX2+ cells in both the rat sub-ventricular zone (SVZ) and sub-granular zone (SGZ) of the hippocampus. In addition, we have identified an extensive, novel population of non-neuronal SOX2+ cells in the rat subfornical organ (SFO). Our findings provide further evidence of 'immature' phenotypes in rodent SCN neurons and, given the extensive expression of SOX2 across these hypothalamic neurons, may identify a common regulatory factor that maintains this unusual neuronal phenotype. Conservation of SCN SOX2 expression in both rat and mouse indicates a functional requirement for this transcription factor that may be integral to the role of these SCN neurons in mediating daily physiological rhythms.


Assuntos
Hipotálamo/metabolismo , Neurônios/metabolismo , Fatores de Transcrição SOXB1/biossíntese , Animais , Hipotálamo/citologia , Immunoblotting , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/citologia , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição SOXB1/análise
15.
J Mol Endocrinol ; 53(2): 271-80, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25139489

RESUMO

The transcription factor gene Egr1 is necessary for female fertility; EGR1 protein is an established molecular regulator of adult female gonadotroph function where it mediates GNRH-stimulated transcription of the Lhb gene. Recent studies have also implicated pituitary EGR1 in the mediation of other physiological signals indicating an integrative function. However, the role of EGR1 in males is less well defined and this uncertainty is compounded by the absence of cellular expression data in the male pituitary gland. The aim of this study, therefore, was to define the distribution of Egr1 gene expression in the adult male rat pituitary. To further this aim, we have evaluated cellular populations in a transgenic rat model (Egr1-d2EGFP), in which we demonstrate regulated green fluorescent protein (GFP) expression in EGR1+ pituitary cells. Cellular filling by GFP enabled morphological and molecular differentiation of different populations of gonadotrophs; Egr1 transcription and LHB were highly co-localised in a major population of large cells but only minimally co-localised in small GFP+ cells; the latter cells were shown to be largely (80%) composed of minority populations of GH+ somatotrophs (9% of total GH+) and PRL+ lactotrophs (3% of total PRL+). Egr1 transcription was not found in TSH+, ACTH+ or SOX2+ precursor cells and was only minimally co-localised in S-100ß+ folliculostellate cells. Our demonstration that the Egr1 gene is actively and selectively transcribed in a major sub-population of male LHB+ cells indicates a largely conserved role in gonadotroph function and has provided a basis for further defining this role.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Hipófise/metabolismo , Transcrição Gênica , Animais , Proteínas de Transporte/metabolismo , Ciclo Celular/genética , Feminino , Expressão Gênica , Imuno-Histoquímica , Masculino , Ligação Proteica , Transporte Proteico , Ratos
16.
J Mol Neurosci ; 52(1): 138-47, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24458742

RESUMO

ZEB2 is a transcription factor with established roles in neurogenesis but no defined function in postnatal brain despite extensive neuronal expression in telencephalic structures. Multiple, incompletely annotated transcripts derive from the Zeb2 locus; the purpose of the present study was to structurally characterize rat brain Zeb2 transcripts with respect to 3' untranslated (UTR) sequence in order to understand Zeb2 transcript regulation including possible interactions with regulatory molecules such as neuronal miRNAs. We cloned a 5054-nucleotide Zeb2 3' UTR that is included in the most abundant Zeb2 transcript in neonatal rat brain. Unique features of the distal 3' UTR region included a number of brain-specific miRNA target sites; a highly conserved miR-9 target site at 3' UTR position 4097 was selected for functional verification in transfection experiments. Parallel analysis of Zeb2 transcript, ZEB2 protein and miR-9 levels across postnatal brain cortical development revealed a significant accumulation of ZEB2 protein levels only between postnatal days P2 and P5 that was associated with an acute loss of postnatal miR-9 expression in cortex. These studies demonstrate novel features of Zeb2 gene expression in postnatal rat brain and highlight the importance of full transcript annotation for identifying the complement of potential transcript-interacting regulators.


Assuntos
Regiões 3' não Traduzidas , Encéfalo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , MicroRNAs/metabolismo , Neurônios/metabolismo , Proteínas Repressoras/genética , Animais , Encéfalo/citologia , Encéfalo/crescimento & desenvolvimento , Células Cultivadas , Proteínas de Homeodomínio/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Repressoras/metabolismo , Transcrição Gênica , Homeobox 2 de Ligação a E-box com Dedos de Zinco
17.
Hypertension ; 62(5): 866-71, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24001896

RESUMO

Hypertension contributes to multiple forms of cardiovascular disease and thus morbidity and mortality. The mechanisms inducing hypertension remain unclear although the involvement of homeostatic systems, such as the renin-angiotensin and sympathetic nervous systems, is established. A pivotal role of the angiotensin type 1 receptor in the proximal tubule of the kidney for the development of experimental hypertension is established. Yet, other systems are involved. This study tests whether the expression of angiotensin type 1A receptors in catecholaminergic cells contributes to hypertension development. Using a Cre-lox approach, we deleted the angiotensin type 1A receptor from all catecholaminergic cells. This deletion did not alter basal metabolism or blood pressure but delayed the onset of angiotensin-dependent hypertension and reduced the maximal response. Cardiac hypertrophy was also reduced. The knockout mice showed attenuated activation of the sympathetic nervous system during angiotensin II infusion as measured by spectral analysis of the blood pressure. Increased reactive oxygen species production was observed in forebrain regions, including the subfornical organ, of the knockout mouse but was markedly reduced in the rostral ventrolateral medulla. These studies demonstrate that stimulation of the angiotensin type 1A receptor on catecholaminergic cells is required for the full development of angiotensin-dependent hypertension and support an important role for the sympathetic nervous system in this model.


Assuntos
Pressão Sanguínea/fisiologia , Cardiomegalia/metabolismo , Catecolaminas/metabolismo , Hipertensão/metabolismo , Receptor Tipo 1 de Angiotensina/metabolismo , Angiotensina II , Animais , Pressão Sanguínea/efeitos dos fármacos , Cardiomegalia/genética , Cardiomegalia/fisiopatologia , Hipertensão/induzido quimicamente , Hipertensão/genética , Hipertensão/fisiopatologia , Camundongos , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismo , Receptor Tipo 1 de Angiotensina/genética , Órgão Subfornical/efeitos dos fármacos , Órgão Subfornical/metabolismo , Órgão Subfornical/fisiopatologia , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/metabolismo , Sistema Nervoso Simpático/fisiopatologia
18.
J Cancer Res Ther ; 9(4): 733-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24518730

RESUMO

Symptoms of nausea and vomiting can present a diagnostic challenge for physicians. In this article, we report a patient who was found to have synchronous presentation of an ependymoma and pancreatic cancer. This case illustrates some of the diagnostic challenges in patients with constitutional symptoms. Furthermore, it illustrates the importance of surgical intervention as both a diagnostic as well as a therapeutic measure when managing patients with presumed metastatic disease to the brain.


Assuntos
Neoplasias Encefálicas/radioterapia , Ependimoma/radioterapia , Náusea/diagnóstico , Neoplasias Primárias Múltiplas/radioterapia , Neoplasias Pancreáticas/radioterapia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/tratamento farmacológico , Ependimoma/diagnóstico , Ependimoma/tratamento farmacológico , Quarto Ventrículo/patologia , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/tratamento farmacológico , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Primárias Múltiplas/tratamento farmacológico , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/tratamento farmacológico , Radioterapia Adjuvante , Proteínas S100/metabolismo , Vômito
19.
Clin Neurol Neurosurg ; 115(4): 425-31, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22763191

RESUMO

OBJECTIVE: The population suffering from chronic/subacute subdural hematomas (SDHs) generally includes elderly patients with co-morbidities; therefore the success of less invasive surgical techniques has been of long standing interest. The optimum treatment option for chronic/subacute SDH has not been well established. We report our retrospective outcomes of SDH drainage through a subdural evacuating port system (SEPS). PATIENTS AND METHODS: Fifty-two consecutive adult patients with chronic/subacute SDH treated with SEPS (total 64 procedures), over a period of 3 years (June 2006-June 2009), were included. 9/52 patients had SEPS performed for bilateral SDHs. Three patients had SEPS placed for recurrent SDH. This retrospective study was approved by the Institutional Review Board of SUNY Upstate Medical University and Crouse Hospital. RESULTS: Overall 38/52 patients (73%) showed clinical improvement, 10/52 patients (19%) did not show any clinical improvement and 4/52 (8%) patients became clinically worse after the SEPS placement during initial hospitalization. 41/52 patients, treated initially with SEPS were followed as outpatients. 32/41 patients improved, returning to baseline neurological status, 5/41 patients improved, but still had some residual symptoms. The remaining 4/41 patients, presented with recurrent symptoms and had recurrent SDH on CT scans. During the in-hospital post-SEPS period, 8 SDH had >75% decrease, 17 SDH had between 50 and 75% decrease, 23 SDH had between 25 and 50% decrease and 14 procedures had <25% decrease in maximal width of the SDH on postoperative scans. Outpatient follow up CT scans after SEPS placement were available for 46/64 procedures. At final outpatient follow up, 33/46 SDHs showed >75% decrease in maximal thickness, 4/46 SDH showed between 50 and 75% and 2/46 SDH showed between 25 and 50% decreases in maximal width of chronic SDH. However, in 7/46 patients, SDH re-accumulated (i.e. increased in thickness) as outpatients, after initial response to treatment on post-operative in-hospital CT scans. CONCLUSION: SEPS is an effective, relatively safe and convenient treatment strategy with low invasiveness; among management options of chronic/subacute SDH.


Assuntos
Drenagem/instrumentação , Drenagem/métodos , Hematoma Subdural Agudo/cirurgia , Hematoma Subdural Crônico/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/métodos , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Ambulatórios , Anestesia Local , Craniotomia , Drenagem/efeitos adversos , Feminino , Seguimentos , Cefaleia/epidemiologia , Cefaleia/etiologia , Humanos , Hemorragias Intracranianas/epidemiologia , Hemorragias Intracranianas/etiologia , Masculino , Pessoa de Meia-Idade , Pneumocefalia/etiologia , Complicações Pós-Operatórias/epidemiologia , Tomografia Computadorizada por Raios X , Falha de Tratamento , Resultado do Tratamento
20.
Hum Mol Genet ; 21(26): 5429-42, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23001561

RESUMO

The zinc-finger, E-box-binding homeobox-2 (Zeb2) gene encodes a SMAD-interacting transcription factor that has diverse roles in development and disease. Mutations at the hZeb2 locus cause Mowat-Wilson syndrome (MWS), a genetic disorder that is associated with mental retardation and other, case- and sex-dependent clinical features. Recent studies have detailed microRNA-mediated control of Zeb2, but little is known about the genomic context of this gene or of enhancer sequences that may direct its diverse functions. Here, we describe a novel transgenic rodent model in which Zeb2 regulatory sequence has been disrupted, resulting in a postnatal developmental phenotype that is autosomal dominant. The phenotype exhibits a genotype-by-sex interaction and manifests primarily as an acute attenuation of postnatal kidney development in males. Other aspects of embryonic and neonatal development, including neuronal, are unaffected. The transgene insertion site is associated with a 12 kb deletion, 1.2 Mb upstream of Zeb2, within a 4.1 Mb gene desert. A conserved sequence, derived from the deleted region, enhanced Zeb2 promoter activity in transcription assays. Tissue and temporal restriction of this enhancer activity may involve postnatal changes in proteins that bind this sequence. A control human/mouse VISTA enhancer (62 kb upstream of Zeb2) also up-regulated the Zeb2 promoter, providing evidence of a string of conserved distal enhancers. The phenotype arising from deletion of one copy of the extreme long-range enhancer indicates a critical role for this enhancer at one developmental stage. Haploinsufficiency of Zeb2 in this developmental context reflects inheritance of MWS and may underlie some sex-dependent, non-neural characteristics of this human inherited disorder.


Assuntos
Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Fenótipo , Proteínas Repressoras/genética , Animais , Sequência Conservada/genética , Fácies , Feminino , Deleção de Genes , Perfilação da Expressão Gênica , Loci Gênicos , Genótipo , Doença de Hirschsprung/genética , Doença de Hirschsprung/patologia , Proteínas de Homeodomínio/metabolismo , Humanos , Deficiência Intelectual/genética , Deficiência Intelectual/patologia , Rim/embriologia , Rim/crescimento & desenvolvimento , Masculino , Camundongos , Microcefalia/genética , Microcefalia/patologia , Células NIH 3T3 , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Ratos Transgênicos , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transgenes , Regulação para Cima , Homeobox 2 de Ligação a E-box com Dedos de Zinco
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