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1.
Front Oncol ; 10: 605314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33365273

RESUMO

Thrombotic complications are the second leading cause of death among oncology patients worldwide. Enhanced thrombogenesis has multiple origins and may result from a deregulation of megakaryocyte platelet production in the bone marrow, the synthesis of coagulation factors in the liver, and coagulation factor signaling upon cancer and the tumor microenvironment (TME). While a hypercoagulable state has been attributed to factors such as thrombocytosis, enhanced platelet aggregation and Tissue Factor (TF) expression on cancer cells, further reports have suggested that coagulation factors can enhance metastasis through increased endothelial-cancer cell adhesion and enhanced endothelial cell activation. Autophagy is highly associated with cancer survival as a double-edged sword, as can both inhibit and promote cancer progression. In this review, we shall dissect the crosstalk between the coagulation cascade and autophagic pathway and its possible role in metastasis and cancer-associated thrombosis formation. The signaling of the coagulation cascade through the autophagic pathway within the hematopoietic stem cells, the endothelial cell and the cancer cell are discussed. Relevant to the coagulation cascade, we also examine the role of autophagy-related pathways in cancer treatment. In this review, we aim to bring to light possible new areas of cancer investigation and elucidate strategies for future therapeutic intervention.

2.
Front Pediatr ; 6: 63, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29740570

RESUMO

Fetal sex is associated with striking differences during in utero development, fetal-to-neonatal transition, and postnatal morbidity and mortality. Male sex fetuses are apparently protected while in utero resulting in a higher secondary sex rate for males than for females. However, during fetal-to-neonatal transition and thereafter in the newborn period, female exhibits a greater degree of maturation that translates into a better capacity to stabilize, less incidence of prematurity and prematurity-associated morbidities, and better long-term outcomes. The present review addresses the influence of sex during gestation and postnatal adaptation that includes the establishment of an adult-type circulation, the initiation of breathing, endurance when confronted with perinatal hypoxia ischemia, and a gender-related different response to drugs. The intrinsic mechanisms explaining these differences in the perinatal period remain elusive and further experimental and clinical research are therefore stringently needed if an individual oriented therapy is to be developed.

3.
Int J Neonatal Screen ; 4(1): 3, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33072929

RESUMO

Despite the progress in the fetal echocardiographic detection of congenital critical heart defects and neonatal physical examination, a significant number of newborn infants are discharged and readmitted to the hospital in severe condition due to cardiac failure or collapse. The aim of this study was to assess the incidence of undetected critical congenital heart disease (CCHD) by a pulse oximetry-screening program in the maternity wards of hospitals with Perinatal Services in a specific geographic area. This is a prospective observational study performed in in the health area corresponding to the city of Valencia. Eligible infants were consecutively admitted newborn infants in the maternities of the participating hospitals with negative fetal echocardiography after normal physical examination in the delivery room. All patients were screened following a specific pulse oximetry protocol before discharge. A total of 8856 newborn infants were screened. A total of three babies presented with severe congenital cardiac malformation and two babies presented with early onset sepsis. Sensitivity was 100% and specificity was 99.97%, with a positive predictive value of 60% and negative predictive value of 100%. Pulse oximetry screening programs in the early neonatal period constitute a valuable tool to avoid inadvertent hospital discharge of severe cardiac malformations and the subsequent life-threatening complications derived.

4.
Mol Pain ; 6: 95, 2010 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-21167062

RESUMO

BACKGROUND: The transcriptional repressor DREAM (downstream regulatory element antagonist modulator) controls the expression of prodynorphin and has been involved in the modulation of endogenous responses to pain. To investigate the role of DREAM in central mechanisms of pain sensitization, we used a line of transgenic mice (L1) overexpressing a Ca(2+)- and cAMP-insensitive DREAM mutant in spinal cord and dorsal root ganglia. RESULTS: L1 DREAM transgenic mice showed reduced expression in the spinal cord of several genes related to pain, including prodynorphin and BDNF (brain-derived neurotrophic factor) and a state of basal hyperalgesia without change in A-type currents. Peripheral inflammation produced enhancement of spinal reflexes and increased expression of BDNF in wild type but not in DREAM transgenic mice. The enhancement of the spinal reflexes was reproduced in vitro by persistent electrical stimulation of C-fibers in wild type but not in transgenic mice. Exposure to exogenous BDNF produced a long-term enhancement of dorsal root-ventral root responses in transgenic mice. CONCLUSIONS: Our results indicate that endogenous BDNF is involved in spinal sensitization following inflammation and that blockade of BDNF induction in DREAM transgenic mice underlies the failure to develop spinal sensitization.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/fisiologia , Proteínas Interatuantes com Canais de Kv/fisiologia , Proteínas Repressoras/fisiologia , Medula Espinal/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/antagonistas & inibidores , Fator Neurotrófico Derivado do Encéfalo/genética , Regulação da Expressão Gênica , Inflamação , Proteínas Interatuantes com Canais de Kv/genética , Camundongos , Camundongos Transgênicos , Proteínas Mutantes , Fibras Nervosas Amielínicas/fisiologia , Dor/genética , Ratos , Proteínas Repressoras/genética
5.
J Biol Chem ; 284(32): 21218-28, 2009 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-19520845

RESUMO

The degradation of the aromatic compound phenylpropionate (PP) in Escherichia coli K-12 requires the activation of two different catabolic pathways coded by the hca and the mhp gene clusters involved in the mineralization of PP and 3-hydroxyphenylpropionate (3HPP), respectively. The compound 3-(2,3-dihydroxyphenyl)propionate (DHPP) is a common intermediate of both pathways which must be cleaved by the MhpB dioxygenase before entering into the primary cell metabolism. Therefore, the degradation of PP has to be controlled by both its specific regulator (HcaR) but also by the MhpR regulator of the mhp cluster. We have demonstrated that 3HPP and DHPP are the true and best activators of MhpR, whereas PP only induces no response. However, in vivo and in vitro transcription experiments have demonstrated that PP activates the MhpR regulator synergistically with the true inducers, representing the first case of such a peculiar synergistic effect described for a bacterial regulator. The three compounds enhanced the interaction of MhpR with its DNA operator in electrophoretic mobility shift assays. Inducer binding to MhpR is detected by circular dichroism and fluorescence spectroscopies. Fluorescence quenching measurements have revealed that the true inducers (3HPP and DHPP) and PP bind with similar affinities and independently to MhpR. This type of dual-metabolite synergy provides great potential for a rapid modulation of gene expression and represents an important feature of transcriptional control. The mhp regulatory system is an example of the high complexity achievable in prokaryotes.


Assuntos
Dioxigenases/fisiologia , Proteínas de Escherichia coli/metabolismo , Escherichia coli/fisiologia , Regulação Bacteriana da Expressão Gênica , Fenilpropionatos/metabolismo , Dicroísmo Circular , Análise por Conglomerados , Dioxigenases/metabolismo , Relação Dose-Resposta a Droga , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Ligantes , Modelos Biológicos , Modelos Químicos , Modelos Genéticos , Família Multigênica , Espectrometria de Fluorescência/métodos , Transcrição Gênica
6.
Mol Endocrinol ; 23(6): 862-70, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19299442

RESUMO

G protein-coupled receptors (GPCRs) are involved in the pathophysiology of a wide range of diseases and constitute an attractive therapeutic target. In the thyroid gland, TSH receptor (TSHR), a member of the GPCR family, is a major regulator of thyroid differentiation and function. Alterations in TSHR activity are often involved in the development of pathologies such as thyroid cancer and thyroid enlargement (goiter). Here we show that DREAM (downstream regulatory element antagonist modulator) modulates TSHR activity through a direct protein-protein interaction that promotes coupling between the receptor and Galphas. In transgenic mice, DREAM overexpression provokes a marked enlargement of the thyroid gland. Increased levels of DREAM protein were observed in human multinodular goiters, suggesting a novel etiopathogenic mechanism in nodular development in humans. Taken together, these findings identify a mechanism for the control of TSHR activity and provide a new approach for the study and treatment of thyroid pathologies associated with impaired TSHR function.


Assuntos
Proteínas Interatuantes com Canais de Kv/metabolismo , Proteínas Repressoras/metabolismo , Glândula Tireoide/crescimento & desenvolvimento , Glândula Tireoide/patologia , Animais , Biomarcadores/metabolismo , Bovinos , Diferenciação Celular , Linhagem Celular , Proliferação de Células , AMP Cíclico/metabolismo , Bócio/metabolismo , Bócio/patologia , Humanos , Proteínas Interatuantes com Canais de Kv/química , Camundongos , Camundongos Transgênicos , Peptídeos/metabolismo , Ligação Proteica , Receptores da Tireotropina/metabolismo , Proteínas Repressoras/química , Transdução de Sinais , Glândula Tireoide/metabolismo
7.
J Neurosci ; 25(47): 10822-30, 2005 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-16306395

RESUMO

The Na+/Ca2+ exchangers NCX1, NCX2, and NCX3 are vital for the control of cellular Ca2+ homeostasis. Here, we show that a doublet of downstream regulatory element sites in the promoter of the NCX3 gene mediates transcriptional repression of NCX3 by the Ca2+-modulated transcriptional repressor downstream regulatory element antagonist modulator (DREAM). Overexpression of a DREAM EF-hand mutant insensitive to Ca2+ (EFmDREAM) in hippocampus and cerebellum of transgenic mice significantly reduced NCX3 mRNA and protein levels without modifying NCX1 and NCX2 expression. Cerebellar granules from EFmDREAM transgenic mice showed increased levels of cytosolic Ca2+ and were more vulnerable to increased Ca2+ influx after partial opening of voltage-gated plasma membrane Ca2+ channels induced by increasing K+ in the culture medium but survived better in the conditions of reduced Ca2+ influx prevailing in low extracellular K+. Overexpression of NCX3 in EFmDREAM transgenic granules using a lentiviral vector restored the normal survival response to high K+ observed in wild-type granules. Thus, the downregulation of the regulator of Ca2+ homeostasis NCX3 by Ca2+-regulated DREAM is a striking example of the autoregulatory property of the Ca2+ signal in neurons.


Assuntos
Cálcio/metabolismo , Cerebelo/fisiologia , Homeostase/fisiologia , Proteínas Interatuantes com Canais de Kv/fisiologia , Proteínas de Membrana Transportadoras/metabolismo , Neurônios/fisiologia , Trocador de Sódio e Cálcio/metabolismo , Motivos de Aminoácidos/genética , Animais , Encéfalo/metabolismo , Sinalização do Cálcio/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Cerebelo/metabolismo , Grânulos Citoplasmáticos/metabolismo , Regulação para Baixo , Humanos , Membranas Intracelulares/metabolismo , Proteínas Interatuantes com Canais de Kv/genética , Proteínas de Membrana Transportadoras/genética , Camundongos , Camundongos Transgênicos , Mutação , Neurônios/metabolismo , Concentração Osmolar , Regiões Promotoras Genéticas , Trocador de Sódio e Cálcio/genética
8.
Crit Rev Neurobiol ; 16(1-2): 43-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15581398

RESUMO

Over the last 20 years, great effort has been made to decipher the molecular mechanisms used by cells to transform a cytosolic Ca2+ signal into specific, finely-controlled changes in gene expression. Several previous reviews addressed the variety of regulatory mechanisms that participate in Ca2+ -dependent gene expression in neurons (Carafoli et al., 2001; Mellstrom and Naranjo 2001; West et al., 2001). Nevertheless, recent discoveries have revealed new players and new interactions that tune this process. In this review, we will use the four promoters that regulate the expression of the brain-derived neurotrophic factor (BDNF) gene as a magnificent scenario in which these mechanisms intermingle to show the complexity of Ca2+ -dependent gene expression.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/genética , Sinalização do Cálcio/genética , Cálcio/fisiologia , Regulação da Expressão Gênica/fisiologia , Animais , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Humanos
9.
FEMS Microbiol Rev ; 28(4): 503-18, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15374664

RESUMO

The current knowledge on the genetics and biochemistry of the catabolism of aromatic compounds in Escherichia coli settles the basis to consider these pathways as a model system to study the complex molecular mechanisms that control the expression of the genes involved in the metabolism of less-preferred carbon sources in this paradigmatic organism. Two different levels of regulation are reviewed: (i) the specific regulatory mechanisms that drive the expression of the catabolic genes when the cognate inducer, i.e., the substrate of the pathway or an intermediate metabolite, is available, and (ii) the global or superimposed regulation that adjust the expression of the catabolic clusters to the general physiological status of the cell.


Assuntos
Escherichia coli/genética , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Hidrocarbonetos Aromáticos/metabolismo , Transativadores/metabolismo , Adaptação Fisiológica , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Genes Bacterianos , Família Multigênica , Transativadores/genética
10.
J Neurosci ; 24(23): 5346-55, 2004 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-15190107

RESUMO

The molecular mechanisms controlling the oscillatory synthesis of melatonin in rat pineal gland involve the rhythmic expression of several genes including arylalkylamine N-acetyltransferase (AA-NAT), inducible cAMP early repressor (ICER), and Fos-related antigen-2 (fra-2). Here we show that the calcium sensors downstream regulatory element antagonist modulator/potassium channel interacting protein (DREAM/KChIP)-3 and KChIP-1, -2 and -4 bind to downstream regulatory element (DRE) sites located in the regulatory regions of these genes and repress basal and induced transcription from ICER, fra-2 or AA-NAT promoters. Importantly, we demonstrate that the endogenous binding activity to DRE sites shows day-night oscillations in rat pineal gland and retina but not in the cerebellum. The peak of DRE binding activity occurs during the day period of the circadian cycle, coinciding with the lowest levels of fra-2, ICER, and AA-NAT transcripts. We show that a rapid clearance of DRE binding activity during the entry in the night period is related to changes at the posttranscriptional level of DREAM/KChIP. The circadian pattern of DREAM/KChIP activity is maintained under constant darkness, indicating that an endogenous clock controls DREAM/KChIP function. Our data suggest involvement of the family of DREAM repressors in the regulation of rhythmically expressed genes engaged in circadian rhythms.


Assuntos
Relógios Biológicos , Proteínas de Ligação ao Cálcio/metabolismo , Ritmo Circadiano , Melatonina/metabolismo , Glândula Pineal/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Canais de Potássio/metabolismo , Animais , Arilamina N-Acetiltransferase/metabolismo , AMP Cíclico/metabolismo , Modulador de Elemento de Resposta do AMP Cíclico , Proteínas de Ligação a DNA/metabolismo , Antígeno 2 Relacionado a Fos , Regulação da Expressão Gênica , Proteínas Interatuantes com Canais de Kv , Masculino , Ratos , Ratos Wistar , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica
11.
Microbiology (Reading) ; 149(Pt 12): 3595-3601, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14663091

RESUMO

Active containment systems based on the controlled expression of a lethal gene are designed to increase containment of recombinant micro-organisms used for environmental applications. A major drawback in containment is the existence of mutations that generate surviving cells that cease to respond to the toxic effect of the lethal function. In this work the authors have developed for the first time a strategy to reduce the problem of mutations and increase the efficiency of containment based on the combination of two lethal functions acting on different cellular targets of major concern in containment, DNA and RNA, and whose expression is under control of different regulatory signals. To engineer the dual gene containment circuit, two toxin-antitoxin pairs, i.e. the colicin E3-immunity E3 and the EcoRI restriction-modification systems, were combined. The genes encoding the immunity E3 and the EcoRI methyltransferase proteins (antitoxins) were stably inserted into the chromosome of the host cell, whereas the broad-host-range lethal genes encoding the colicin E3 RNase and the EcoRI restriction endonuclease (toxins) were flanking the contained trait in a plasmid. This dual lethal cassette decreased gene transfer frequencies, through killing of the recipient cells, by eight orders of magnitude, which provides experimental evidence that the anticipated containment level due to the combination of single containment systems is generally achieved. Survivors that escaped killing were analysed and the mutational events involved were characterized.


Assuntos
Colicinas , Contenção de Riscos Biológicos/métodos , Microbiologia Ambiental , Proteínas de Escherichia coli , Genes Letais , Engenharia Genética , Proteínas de Bactérias/genética , Sequência de Bases , DNA Recombinante/genética , Escherichia coli/genética , Genes Bacterianos , Mutação , Plasmídeos/genética , Recombinação Genética , DNA Metiltransferases Sítio Específica (Adenina-Específica)/genética
12.
J Biol Chem ; 278(30): 27575-85, 2003 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-12748194

RESUMO

The mhp gene cluster from Escherichia coli constitutes a model system to study bacterial degradation of 3-(3-hydroxyphenyl)propionic acid (3HPP). In this work the regulation of the inducible mhp catabolic genes has been studied by genetic and biochemical approaches. The Pr and Pa promoters, which control the expression of the divergently transcribed mhpR regulatory gene and mhp catabolic genes, respectively, show a peculiar arrangement leading to transcripts that are complementary at their 5'-ends. By using Pr-lacZ and Pa-lacZ translational fusions and gel retardation assays, we have shown that the mhpR gene product behaves as a 3HPP-dependent activator of the Pa promoter, being the expression from Pr constitutive and MhpR-independent. DNase I footprinting experiments and mutational analysis mapped an MhpR-protected region, centered at position -58 with respect to the Pa transcription start site, which is indispensable for MhpR binding and in vivo activation of the Pa promoter. Superimposed in the specific MhpR-mediated regulation of the Pa promoter, we have observed a strict catabolite repression control carried out by the cAMP receptor protein (CRP) that allows expression of the mhp catabolic genes when the preferred carbon source (glucose) is not available and 3HPP is present in the medium. Gel retardation assays revealed that the specific activator, MhpR, is essential for the binding of the second activator, CRP, to the Pa promoter. Such peculiar synergistic transcription activation has not yet been observed in other aromatic catabolic pathways, and the MhpR activator becomes the first member of the IclR family of transcriptional regulators that is indispensable for recruiting CRP to the target promoter.


Assuntos
Ácidos Cumáricos/química , Escherichia coli/metabolismo , Motivos de Aminoácidos , Sequência de Bases , Sítios de Ligação , Proteínas de Transporte , Clonagem Molecular , Ácidos Cumáricos/metabolismo , Proteína Receptora de AMP Cíclico/metabolismo , DNA/metabolismo , Desoxirribonuclease I/metabolismo , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Glucose/metabolismo , Modelos Genéticos , Dados de Sequência Molecular , Família Multigênica , Plasmídeos/metabolismo , Regiões Promotoras Genéticas , Biossíntese de Proteínas , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sequência de DNA , Transcrição Gênica , Ativação Transcricional , beta-Galactosidase/metabolismo
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