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1.
J Biomed Inform ; 51: 176-90, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24909817

RESUMO

This study presents a Web platform (http://3dfd.ujaen.es) for computing and analyzing the 3D fractal dimension (3DFD) from volumetric data in an efficient, visual and interactive way. The Web platform is specially designed for working with magnetic resonance images (MRIs) of the brain. The program estimates the 3DFD by calculating the 3D box-counting of the entire volume of the brain, and also of its 3D skeleton. All of this is done in a graphical, fast and optimized way by using novel technologies like CUDA and WebGL. The usefulness of the Web platform presented is demonstrated by its application in a case study where an analysis and characterization of groups of 3D MR images is performed for three neurodegenerative diseases: Multiple Sclerosis, Intrauterine Growth Restriction and Alzheimer's disease. To the best of our knowledge, this is the first Web platform that allows the users to calculate, visualize, analyze and compare the 3DFD from MRI images in the cloud.


Assuntos
Encefalopatias/patologia , Encéfalo/patologia , Imageamento Tridimensional/métodos , Internet , Reconhecimento Automatizado de Padrão/métodos , Software , Interface Usuário-Computador , Algoritmos , Fractais , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
2.
Hum Reprod Open ; 2022(2): hoac016, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464885

RESUMO

STUDY QUESTION: Do women with endometriosis have a different endometrial gene expression profile at the time of embryo implantation than women without endometriosis? SUMMARY ANSWER: The endometrial gene expression profile of women with endometriosis differs from that of women without endometriosis at the mid-secretory phase, although the differences are small. WHAT IS KNOWN ALREADY: About 50% of women with endometriosis suffer infertility. Several molecular studies have suggested impaired endometrial receptivity in women with endometriosis, while others have detected no dysregulation of endometrial receptivity. Nevertheless, the previous endometrial transcriptome studies comparing women with and without endometriosis have been performed in small sample size with limited statistical power. We set out to systematically search and compile data of endometrial gene expression signatures at the receptive phase in women with endometriosis versus control women. Based on the obtained data, we conducted a meta-analysis of differentially expressed genes in order to raise the power of the analysis for identifying the molecular profiles of receptive phase endometria in endometriosis. STUDY DESIGN SIZE DURATION: A systematic literature search was conducted up to February 2022 following PRISMA criteria and included PubMed, Cochrane and Web of Science databases. For the systematic search, the term 'endometriosis' was paired with the terms 'transcriptomics', 'transcriptome', 'gene expression', 'RNA-seq', 'sequencing' and 'array', by using the Boolean operator 'AND' to connect them. Articles written in English were screened and interrogated for data extraction. PARTICIPANTS/MATERIALS SETTING METHODS: A meta-analysis was performed on the selected studies to extract the differentially expressed genes described at the mid-secretory phase in women with endometriosis versus women without endometriosis in natural cycles, using the robust rank aggregation method. In total, transcriptome data of 125 women (78 patients and 47 controls) were meta-analysed, with a special focus on endometrial receptivity-specific genes based on commercial endometrial receptivity tests. MAIN RESULTS AND THE ROLE OF CHANCE: In total, 8 studies were eligible for the quantitative meta-analysis, gathering transcriptome data from the mid-secretory phase endometria of 125 women. A total of 7779 differentially expressed transcripts between the study groups were retrieved (3496 up-regulated and 4283 down-regulated) and were meta-analysed. After stringent multiple correction, there was no differential expression of any single molecule in the endometrium of women with endometriosis versus controls, while enrichment analysis detected that the pathways of chemotaxis and locomotion are dysregulated in endometriosis. Further analysis of endometrial receptivity-specific genes highlighted dysregulation of C4BPA, MAOA and PAEP and enrichment of immune and defence pathways in women with endometriosis. LIMITATIONS REASONS FOR CAUTION: Most of the studies included into the meta-analysis were relatively small and had different study designs, which might have contributed to a bias. WIDER IMPLICATIONS OF THE FINDINGS: The current meta-analysis supports the hypothesis that endometrial receptivity is altered in women with endometriosis, although the changes are small. The molecules and pathways identified could serve as future biomarkers and therapeutical targets in detecting and treating endometriosis-associated infertility. STUDY FUNDING/COMPETING INTERESTS: The authors declare no competing interests. This work was supported by the Spanish Ministry of Education, Culture and Sport [grant FPU15/01193] and the Margarita Salas program for the Requalification of the Spanish University system [grant UJAR01MS]; Spanish Ministry of Economy, Industry and Competitiveness (MINECO) and European Regional Development Fund (FEDER): grants RYC-2016-21199 and ENDORE SAF2017-87526-R; Programa Operativo FEDER Andalucía (B-CTS-500-UGR18; A-CTS-614-UGR20); the Junta de Andalucía [BIO-302; and PAIDI P20_00158]; the University of Jaén [PAIUJA-EI_CTS02_2017]; the University of Granada, Plan Propio de Investigación 2016, Excellence actions: Units of Excellence; Unit of Excellence on Exercise and Health (UCEES), and by the Junta de Andalucía, Consejería de Conocimiento, Investigación y Universidades and European Regional Development Fund (ERDF), ref. SOMM17/6107/UGR; the Estonian Research Council (grant PRG1076); Horizon 2020 innovation (ERIN, grant no. EU952516) of the European Commission and Enterprise Estonia (grant EU48695). TRIAL REGISTRATION NUMBER: The systematic review was registered at PROSPERO (identifier: CRD42020122054).

3.
Biol Reprod ; 84(4): 801-15, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20864642

RESUMO

Eutopic endometrium in endometriosis has molecular evidence of resistance to progesterone (P(4)) and activation of the PKA pathway in the stromal compartment. To investigate global and temporal responses of eutopic endometrium to P(4), we compared early (6-h), intermediate (48-h), and late (14-Day) transcriptomes, signaling pathways, and networks of human endometrial stromal fibroblasts (hESF) from women with endometriosis (hESF(endo)) with hESF from women without endometriosis (hESF(nonendo)). Endometrial biopsy samples were obtained from subjects with and without mild peritoneal endometriosis (n = 4 per group), and hESF were isolated and treated with P(4) (1 µM) plus estradiol (E(2)) (10 nM), E(2) alone (10 nM), or vehicle for up to 14 days. Total RNA was subjected to microarray analysis using a Gene 1.0 ST (Affymetrix) platform and analyzed by using bioinformatic algorithms, and data were validated by quantitative real-time PCR and ELISA. Results revealed unique kinetic expression of specific genes and unique pathways, distinct biological and molecular processes, and signaling pathways and networks during the early, intermediate, and late responses to P(4) in both hESF(nonendo) and hESF(endo), although a blunted response to P(4) was observed in the latter. The normal response of hESF to P(4) involves a tightly regulated kinetic cascade involving key components in the P(4) receptor and MAPK signaling pathways that results in inhibition of E(2)-mediated proliferation and eventual differentiation to the decidual phenotype, but this was not established in the hESF(endo) early response to P(4). The abnormal response of this cell type to P(4) may contribute to compromised embryonic implantation and infertility in women with endometriosis.


Assuntos
Endometriose/genética , Endometriose/metabolismo , Endométrio/efeitos dos fármacos , Endométrio/metabolismo , Progesterona/farmacologia , Adulto , Sequência de Bases , Estudos de Casos e Controles , Primers do DNA/genética , Resistência a Medicamentos/genética , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Técnicas In Vitro , Pessoa de Meia-Idade , Doenças Peritoneais/genética , Doenças Peritoneais/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos
4.
Hum Reprod ; 25(12): 3012-24, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20889529

RESUMO

BACKGROUND: In vitro culture (IVC) and IVF of preimplantation mouse embryos are associated with changes in gene expression. It is however not known whether ICSI has additional effects on the transcriptome of mouse blastocysts. METHODS: We compared gene expression and development of mouse blastocysts produced by ICSI and cultured in Whitten's medium (ICSI(WM)) or KSOM medium with amino acids (ICSI(KSOMaa)) with control blastocysts flushed out of the uterus on post coital Day 3.5 (in vivo). In addition, we compared gene expression in embryos generated by IVF or ICSI using WM. Global pattern of gene expression was assessed using the Affymetrix 430 2.0 chip. RESULTS: Blastocysts from ICSI fertilization have a reduction in the number of trophoblastic and inner cell mass cells compared with embryos generated in vivo. Approximately 1000 genes are differentially expressed between ICSI blastocyst and in vivo blastocysts; proliferation, apoptosis and morphogenetic pathways are the most common pathways altered after IVC. Unexpectedly, expression of only 41 genes was significantly different between embryo cultured in suboptimal conditions (WM) or optimal conditions (KSOM(aa)). CONCLUSIONS: Our results suggest that fertilization by ICSI may play a more important role in shaping the transcriptome of the developing mouse embryo than the culture media used.


Assuntos
Blastocisto/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Injeções de Esperma Intracitoplásmicas , Animais , Proteínas de Ligação a DNA/biossíntese , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário , Feminino , Desacetilase 6 de Histona , Histona Desacetilases/biossíntese , Histona-Lisina N-Metiltransferase , Camundongos , Proteína de Leucina Linfoide-Mieloide/biossíntese , Análise Serial de Proteínas , Fatores de Transcrição/biossíntese
5.
Genomics ; 93(2): 120-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18950700

RESUMO

The behaviors of autism overlap with a diverse array of other neurological disorders, suggesting common molecular mechanisms. We conducted a large comparative analysis of the network of genes linked to autism with those of 432 other neurological diseases to circumscribe a multi-disorder subcomponent of autism. We leveraged the biological process and interaction properties of these multi-disorder autism genes to overcome the across-the-board multiple hypothesis corrections that a purely data-driven approach requires. Using prior knowledge of biological process, we identified 154 genes not previously linked to autism of which 42% were significantly differentially expressed in autistic individuals. Then, using prior knowledge from interaction networks of disorders related to autism, we uncovered 334 new genes that interact with published autism genes, of which 87% were significantly differentially regulated in autistic individuals. Our analysis provided a novel picture of autism from the perspective of related neurological disorders and suggested a model by which prior knowledge of interaction networks can inform and focus genome-scale studies of complex neurological disorders.


Assuntos
Transtorno Autístico/genética , Genoma Humano , Doenças do Sistema Nervoso/genética , Estudos de Casos e Controles , Expressão Gênica , Redes Reguladoras de Genes/genética , Humanos , Modelos Genéticos , Filogenia , Irmãos , Biologia de Sistemas
6.
Comput Methods Programs Biomed ; 175: 129-137, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31104702

RESUMO

BACKGROUND AND OBJECTIVE: Knowing whether a subject is conscious or not is a current challenge with a deep potential clinical impact. Recent theoretical considerations suggest that consciousness is linked to the complexity of distributed interactions within the corticothalamic system. The fractal dimension (FD) is a quantitative parameter that has been extensively used to analyse the complexity of structural and functional patterns of the human brain. In this study we investigate FD to assess whether it can discriminate between consciousness and different states of unconsciousness in healthy individuals. METHODS: We study 69 high-density electroencephalogram (hd-EEG) measurements after transcranial magnetic stimulation (TMS) in 18 healthy subjects progressing from wakefulness to non-rapid eye movement (NREM) sleep and sedation induced by different anaesthetic agents (xenon and propofol). We quantify the integration of thalamocortical networks by calculating the FD of a spatiotemporal voxelization obtained from the locations of all sources that are significantly activated by the perturbation (4DFD). Moreover, we study the temporal evolution of the evoked spatial distributions and compute a measure of the differentiation of the response by means of the Higuchi FD (HFD). Finally, a Fractal Dimension Index (FDI) of perturbational complexity is computed as the product of both quantities: integration FD (4DFD) and differentiation FD (HFD). RESULTS: We found that FDI is significantly lower in sleep and sedation when compared to wakefulness and provides an almost perfect intra-subject discrimination between conscious and unconscious states. CONCLUSIONS: These results support the combination of FD measures of cortical integration and cortical differentiation as a novel paradigm of tracking complex spatiotemporal dynamics in the brain that could provide further insights into the link between complexity and the brain's capacity to sustain consciousness.


Assuntos
Estado de Consciência , Eletroencefalografia , Estimulação Magnética Transcraniana , Inconsciência , Adolescente , Adulto , Anestesia , Encéfalo/diagnóstico por imagem , Feminino , Fractais , Voluntários Saudáveis , Humanos , Masculino , Propofol , Processamento de Sinais Assistido por Computador , Sono , Vigília , Xenônio , Adulto Jovem
7.
Transl Psychiatry ; 6: e705, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26731442

RESUMO

Several gene expression experiments on autism spectrum disorders have been conducted using both blood and brain tissue. Individually, these studies have advanced our understanding of the molecular systems involved in the molecular pathology of autism and have formed the bases of ongoing work to build autism biomarkers. In this study, we conducted an integrated systems biology analysis of 9 independent gene expression experiments covering 657 autism, 9 mental retardation and developmental delay and 566 control samples to determine if a common signature exists and to test whether regulatory patterns in the brain relevant to autism can also be detected in blood. We constructed a matrix of differentially expressed genes from these experiments and used a Jaccard coefficient to create a gene-based phylogeny, validated by bootstrap. As expected, experiments and tissue types clustered together with high statistical confidence. However, we discovered a statistically significant subgrouping of 3 blood and 2 brain data sets from 3 different experiments rooted by a highly correlated regulatory pattern of 66 genes. This Root 66 appeared to be non-random and of potential etiologic relevance to autism, given their enriched roles in neurological processes key for normal brain growth and function, learning and memory, neurodegeneration, social behavior and cognition. Our results suggest that there is a detectable autism signature in the blood that may be a molecular echo of autism-related dysregulation in the brain.


Assuntos
Transtorno do Espectro Autista/genética , Expressão Gênica/genética , Transtorno do Espectro Autista/sangue , Transtorno do Espectro Autista/fisiopatologia , Encéfalo/fisiopatologia , Humanos
8.
J Mol Biol ; 269(3): 313-25, 1997 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-9199402

RESUMO

Bacteriophage ø29 DNA polymerase shares with other DNA-dependent DNA polymerases several regions of amino acid homology along the primary structure. Among them, motif B, characterized by the consensus +x3Kx(6-7)YG (+ being a positively charged amino acid), appears to be specifically conserved in those polymerases that use DNA but not RNA as template. In particular, the lysine residue of this motif is invariant in all members of DNA-dependent polymerases. In this paper we report a mutational analysis of this invariant residue of motif B with the construction and characterization of two mutant proteins in the corresponding residue (Lys383) of ø29 DNA polymerase. Mutant proteins (K383R and K383P) were overexpressed, purified and analyzed under steady-state conditions. In agreement with the modular organization proposed for ø29 DNA polymerase, the exonuclease activity was not affected in either mutant protein. Conversely, mutant K383P showed no detectable capacity to incorporate dNTP substrates using either DNA or TP as primer, although its affinity for DNA was not affected. The conservative substitution of Lys383 by arginine (K383R) resulted in a considerable impairment to use dNTPs, in both processive and non-processive DNA synthesis; the Km for dNTPs being 200-fold higher than that of the wild-type enzyme. Mutant K383R recovered the wild-type polymerase/exonuclease ratio when Mn2+ was used instead of Mg2+ as metal activator, indicating a distorted binding of the [dNTP-metal] chelate at the mutant enzyme active site. The positive charge at residue Lys383 was also critical in the catalysis of deoxynucleotidylation of the terminal protein by ø29 DNA polymerase. The results obtained suggest a direct role for the lysine residue in motif B in forming an evolutionarily conserved DNA templated dNTP binding pocket. Additionally, K383R mutant protein was also affected in the progression from protein-primed initiation to DNA elongation, a switch between two modes of priming that characterizes ø29 DNA replication.


Assuntos
Fagos Bacilares/enzimologia , DNA Polimerase Dirigida por DNA/genética , DNA Polimerase Dirigida por DNA/metabolismo , Desoxirribonucleotídeos/metabolismo , Sequência de Aminoácidos , Fagos Bacilares/genética , Sítios de Ligação , Primers do DNA , Replicação do DNA , DNA Polimerase Dirigida por DNA/química , Lisina , Magnésio/metabolismo , Manganês/metabolismo , Dados de Sequência Molecular , Mutação , Nucleotídeos/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Moldes Genéticos
9.
Rev Neurol ; 40(7): 437-40, 2005.
Artigo em Espanhol | MEDLINE | ID: mdl-15849679

RESUMO

INTRODUCTION: One of the different molecules involved in the development of astrocytomas is nitric oxide (NO), a gaseous radical that, depending on the cell type and the experimental paradigm selected in the pathology, can play either a cytotoxic or a cytoprotective role. DEVELOPMENT: During the development of an astrocytoma NO acts as a tumouricidal agent, although it can also alter vascular reactivity and lead to neovascularisation, thereby contributing to the invasive capacity (aggressiveness) of the tumour. One of the mechanisms of tumoural progression consists in the protein inactivation resulting from the NO nitration of tyrosine from proteins coded for by tumour-suppressing genes, such as p53. Furthermore, in malignant astrocytes, nitrosoglutathione, a natural NO-donor, has been seen to play a role in the chemoresistance displayed against nitrosourea derivatives. The NO excreted by irradiated astrocytoma cells also appears to be involved in the resistance to the radiotherapy shown by non-irradiated cells. CONCLUSIONS: The molecular mechanisms behind the complex and paradoxical activity of NO in glioblastoma multiforme have still not been fully explained and its implications in vivo are even further from being completely understood.


Assuntos
Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/terapia , Óxido Nítrico/metabolismo , Astrocitoma/genética , Astrocitoma/terapia , Neoplasias Encefálicas/genética , Terapia Combinada , Genes p53/genética , Humanos
10.
Neuroscience ; 126(4): 879-87, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15207323

RESUMO

This study examines the expression and cellular distribution pattern of nitric oxide synthase (NOS) isoforms, nitrotyrosine-derived complexes, and the nitric oxide (NO) production in the cerebellum of rats with cirrhosis induced by thioacetamide (TAA). The results showed local changes in the tissue distribution pattern of the NOS isoforms and nitrated proteins in the cerebellum of these animals. Particularly, eNOS immunoreactivity in perivascular glial cells of the white matter was detected only in TAA-treated animals. In addition, although neither neuronal NOS (nNOS) nor inducible NOS (iNOS) cerebellar protein levels appeared to be affected, the endothelial NOS (eNOS) isoform significantly increased its expression, and NO production slightly augmented in TAA-treated rats. These NOS/NO changes may contribute differently to the evolution of the hepatic disease either by maintaining the guanosine monophosphate-NO signal transduction pathways and the physiological cerebellar functions or by inducing oxidative stress and cell damage. This model gives rise to the hypothesis that the upregulation of the eNOS maintains the physiological production of NO, while the iNOS is silenced and the nNOS remains unchanged. The differential NOS-distribution and expression pattern may be one of the mechanisms involved to balance cerebellar NO production in order to minimize TAA toxic injury. These data help elucidate the role of the NOS/NO system in the development and progress of hepatic encephalopathy associated with TAA cirrhosis.


Assuntos
Cerebelo/metabolismo , Cirrose Hepática Experimental/metabolismo , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/metabolismo , Tirosina/análogos & derivados , Animais , Western Blotting/métodos , Modelos Animais de Doenças , Regulação Enzimológica da Expressão Gênica , Imuno-Histoquímica/métodos , Cirrose Hepática Experimental/induzido quimicamente , Masculino , NADPH Desidrogenase/metabolismo , Nitratos/metabolismo , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Nitritos/metabolismo , Ratos , Ratos Wistar , Tioacetamida , Tirosina/metabolismo , Regulação para Cima
11.
J Chem Neuroanat ; 21(4): 289-94, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11429270

RESUMO

The distribution of nitrergic nervous structures in the trout kidney was studied by peroxidase-linked ABC immunostaining procedures using a polyclonal antibody raised against the neuronal isoform of nitric oxide synthase. The nitrergic plexus reaches the kidney along the vasculature, mainly running with the postcardinal vein where nitrergic fibres, microganglia like cellular clusters and isolated neurones were detected. The atubular head-kidney only showed isolated nitrergic fibres close to the larger arteries. On the other hand, the collecting tubules, collecting ducts, large arteries and glomerular arterioles of the tubular middle and posterior trunks were innervated by nitrergic fibres even though immunoreactive neurones were also observed in close apposition to some tubular elements and large arteries. These results suggest that, according to morphofunctional differences between the fish and mammalian kidneys, nitrergic neural structures may be involved in the control of particular renal functions in the rainbow trout.


Assuntos
Rim/enzimologia , Óxido Nítrico Sintase/metabolismo , Oncorhynchus mykiss/metabolismo , Animais , Imuno-Histoquímica , Fibras Nervosas/enzimologia , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase Tipo I
12.
Microsc Res Tech ; 41(6): 456-70, 1998 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-9712194

RESUMO

The vomeronasal organ (VNO) originates from the medial wall of the olfactory pit shortly after the middle of the embryonic period in mammals. The Anlage stage consists of a cellular bud that grows dorsally, caudally, and towards the midline leaving a groove. The following stage, Early Morphogenesis, includes the closure of the vomeronasal groove to form a parasagittal blind-ended tube in the nasal septum, which opens into the nasal and/or oral cavities. The lumen adopts a crescent shape while the epithelial lining differentiates into an increasingly wider epithelium on the concave side and a gradually thinner epithelium on the convex side. The former goes on to occupy a medial position and develops neuroblasts among supporting and undifferentiated cells, with supporting cell nuclei tending to align in the upper rows. The lateral "non-sensory" epithelium furrows, giving a kidney-shaped appearance to the VNO cross section. The next stage, Late Morphogenesis is extended up to a difference in thickness between both epithelia becomes similar to the adult, generally by birth. An increasing number of ciliary generation complexes, larger and more abundant microvilli, and an evident glycocalyx are observed in the neuroepithelium at the luminal surface, while enzymatic activities become more intense. The non-sensory epithelium appears quite mature save for its luminal surface, which is still devoid of cilia. Blood capillaries penetrate the most basal region of the neuroepithelium and vomeronasal glands are very few and immature. At birth, some neurons appear well developed to support certain functionality; however, persistence of architectural, histochemical, and ultrastructural signs of immaturity, suggests that full performance of the VNO does not occur in newborn mammals, but in prepubertal ages.


Assuntos
Órgão Vomeronasal/embriologia , Animais , Humanos , Mamíferos/embriologia , Morfogênese , Roedores/embriologia , Órgão Vomeronasal/crescimento & desenvolvimento
13.
Microsc Res Tech ; 43(1): 34-42, 1998 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-9829457

RESUMO

The frequency of astrocytes, microglia plus oligodendrocytes, and pericytes displaying nuclei was analyzed and quantified in 160-microm-wide strips of the parietal cortex (Par1 region) from young and aged Wistar rats. The study was performed on two groups of rats aged 3-4 and 32-36 months. Quantifications of the glial cell types and pericytes were made in 1-microm-thick sections stained with toluidine blue. Ultrathin sections were also made to analyze the ultrastructural features of these cells during aging. Astrocytes and pericytes increased in number by about 20% and 22%, respectively, with age. These increases were most significant in layers II-IV and V for both cellular types. Clusters of astrocytes were common in these layers of aging rats. The ultrastructural analysis also indicated changes in all cell types that stored inclusions and vacuoles with age, which were particularly abundant in microglial cells. End-feet astrocytes and pericytes surrounding the vascular wall also contained vacuoles and inclusions, and consequently the vascular wall increased in thickness. In conclusion, the aging process increased astrocyte and pericyte populations, but not microglia plus oligodendrocyte populations, in the rat parietal cortex. Although no significant change in nuclear size could be observed in any cell type, all glial cells as well as pericytes underwent morphological ultrastructural changes. These modifications may result from the need to correct possible homeostatic imbalances during aging.


Assuntos
Envelhecimento/fisiologia , Neuroglia/fisiologia , Neuroglia/ultraestrutura , Lobo Parietal/ultraestrutura , Pericitos/fisiologia , Pericitos/ultraestrutura , Animais , Contagem de Células , Senescência Celular/fisiologia , Microscopia Eletrônica , Neuroglia/citologia , Lobo Parietal/citologia , Lobo Parietal/fisiologia , Pericitos/citologia , Ratos , Ratos Wistar
14.
Microsc Res Tech ; 43(1): 75-88, 1998 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-9829462

RESUMO

Neuronal and inducible nitric oxide synthase (nNOS and iNOS) and nitrotyrosine immunoreactivities were localized and semiquantitatively assessed in the cerebral cortex of aged rats by means of light microscopic immunocytochemistry and Western blotting, using a new series of specific polyclonal antibodies. In the aged rats the strongly nNOS-immunoreactive multipolar neurons found in layers II-VI of the cortex of young rats were seen in similar numbers, but showed varicose, vacuolated, and fragmented processes, with an irregular outline and loss of spines. A large number of more weakly nNOS-positive neurons, characterized by a ring of immunoreactive cytoplasm, and not seen in young rats, were observed in layers II-VI of aged rat cortex. While no iNOS-immunopositive neurons were found in the cortex of young rats, a large number of such neurons appeared throughout the aged rat cortex. Nitrotyrosine-positive cells outnumbered total NOS-positive neurons in the cortex of young rats, but this relation was inverted in the aged rats, although these showed a slight increase in the number and staining intensity of nitrotyrosine-positive cells. Western blots of brain extracts showed a several-fold increase in both nNOS- and iNOS-immunoreactive bands in the aged rat, but a less marked increase in nitrotyrosine-containing proteins. The results suggest that while nNOS and iNOS expression is substantially increased in the aged rat cortex, this is not necessarily accompanied by a proportionate increase in nitric oxide synthesis. The mechanisms underlying the increased expression of nNOS and iNOS, and the functional implications of this increase, require elucidation.


Assuntos
Envelhecimento/patologia , Córtex Cerebral/química , Proteínas do Tecido Nervoso/análise , Óxido Nítrico Sintase/análise , Tirosina/análise , Albinismo , Animais , Western Blotting , Córtex Cerebral/patologia , Imuno-Histoquímica , Masculino , Óxido Nítrico Sintase Tipo I , Óxido Nítrico Sintase Tipo II , Ratos , Ratos Wistar , Tirosina/análogos & derivados
15.
Neurosci Lett ; 226(2): 99-102, 1997 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-9159499

RESUMO

We studied the distribution of neuronal nitric oxide synthase (nNOS) in the rat liver with a specific polyclonal antibody by using immunocytochemical procedures in the light microscopic level. Immunoreactive varicose nerve fibers were found forming a dense plexus around the interlobular hepatic artery and the interlobular bile duct in the hepatic hilus, and in the hepatic artery ramifications of the portal triads. The density of nNOS positive nerve fibers decreases with successive portal ramifications, and some non-immune positive nerve fibers were found in the distal portions of the arterial vessels. The presence of the nNOS positive nerve fibers suggests that the possible main functional role could be related with the regulation of hepatic blood circulation and hepatobiliary activities.


Assuntos
Fígado/inervação , Fibras Nervosas/enzimologia , Neurônios/enzimologia , Óxido Nítrico Sintase/análise , Animais , Ductos Biliares Intra-Hepáticos/inervação , Artéria Hepática/inervação , Imuno-Histoquímica , Fígado/citologia , Masculino , Sistema Porta/inervação , Ratos , Ratos Wistar
16.
Neurosci Lett ; 243(1-3): 45-8, 1998 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-9535109

RESUMO

The aim of this work was to study the nitrergic innervation in the liver of the cat using immunocytochemical procedures. At the hepatic hilus, a rich plexus of neuronal nitric oxide synthase immunoreactive (nNOS-IR) nerve fibers and ganglia was detected around the interlobular branch of the bile duct. nNOS-IR nerve fibers were observed running with the components of the intralobular portal triads located close to the hepatic hilus, as well as with a few vessels and ducts of the deeper parenchyma. These latter fibers, beside others located in Glisson's capsule, occasionally showed short ramifications entering the parenchyma itself. The present results suggest that, in the cat liver, nNOS is involved in the autonomic control of hepatic blood flow, with a limited role in the regulation of hepatobiliary excretory activity and hepatocellular metabolic function.


Assuntos
Fígado/inervação , Fibras Nervosas/enzimologia , Óxido Nítrico Sintase/análise , Óxido Nítrico/análise , Animais , Gatos , Gânglios Autônomos/química , Gânglios Autônomos/enzimologia , Masculino , Fibras Nervosas/química
17.
J Nutr Sci Vitaminol (Tokyo) ; 45(2): 231-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10450564

RESUMO

We have previously reported that high-fat diets develop hepatic steatosis and, depending on the fat quality, affect serum lipid levels differently (J Nutr Sci Vitaminol, 1997, 43, 155-160). The aim of this work is to study the influence of high-fat diets (14% sunflower or olive oils) on serum lipids in a model of hepatic acute damage induced by thioacetamide, and their influence when dexamethasone is administered before thioacetamide injection. Serum lipids and hepatic collagen have been evaluated using biochemical methods, and the steatotic process by histological staining. The results showed that hepatic steatosis and fibrosis are developed either by high-fat diets or thioacetamide injection. Pretreatment with dexamethasone did not decrease the hepatic collagen content. Thioacetamide injection alone or pretreatment with dexamethasone produced increase in serum tryglicerides (TG), total cholesterol (TC) and LDL-C in both high-fat diet groups, and a HDL-C increase in the olive-oil group, even though the atherogenic indices (HDL/TC and HDL/TG) were different depending on the enriched diet. The administration of high-fat diets to study the influence of the fat quality on health and disease should be interpreted carefully due to the ability of the diets themselves to cause hepatic damage.


Assuntos
Dexametasona/farmacologia , Gorduras na Dieta/metabolismo , Lipídeos/sangue , Hepatopatias/dietoterapia , Óleos de Plantas/metabolismo , Tioacetamida/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Dexametasona/uso terapêutico , Gorduras na Dieta/administração & dosagem , Histocitoquímica , Laparotomia/veterinária , Fígado/patologia , Hepatopatias/tratamento farmacológico , Masculino , Ratos , Ratos Wistar , Triglicerídeos/sangue
18.
J Nutr Sci Vitaminol (Tokyo) ; 43(1): 155-60, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9151249

RESUMO

This work describes the long-term effects of two different diets, one rich in olive oil and the other in sunflower oil, on serum lipid and lipoprotein levels after the establishment of fatty liver in rats 8 and 15 months old. The serum lipid and lipoprotein levels as well as the steatotic process have been evaluated by biochemical and histological methods, respectively. The results showed that fatty liver was well developed with both long-term high-fat diets, and hepatocytes were filled with many lipid droplets. This process was more evident in the portal zones, where fat hepatocytes were more numerous. Serum total cholesterol (TC) and HDL-C levels were highest in the sunflower oil fed rats, whereas the TG and LDL-C levels were highest in the olive oil group. Finally, the atherogenic indexes (HDL/TC, HDL/LDL, HDL/(TC-HDL)) were higher in the sunflower oil diet group than in the olive oil group.


Assuntos
Gorduras Insaturadas na Dieta/administração & dosagem , Fígado Gorduroso/sangue , Lipídeos/sangue , Óleos de Plantas/administração & dosagem , Animais , Peso Corporal , Dieta , Gorduras Insaturadas na Dieta/efeitos adversos , Gorduras Insaturadas/química , Fígado Gorduroso/etiologia , Lipoproteínas/sangue , Fígado/patologia , Masculino , Azeite de Oliva , Tamanho do Órgão , Óleos de Plantas/efeitos adversos , Óleos de Plantas/química , Ratos , Ratos Wistar , Óleo de Girassol
19.
Rev Neurol ; 31(11): 1054-65, 2000.
Artigo em Espanhol | MEDLINE | ID: mdl-11190874

RESUMO

OBJECTIVE: A review about the possible cellular and molecular mechanisms of aging and related neurodegenerative diseases. DEVELOPMENT: The mechanisms involved in neuronal decrease, connectivity losses and glial reactivity, detected both in neurodegenerative (Alzheimer's disease) and physiological aging, are analyzed from the morphological and histological point of view to provide the morphofunctional base of the cognitive and intellectual alterations characterizing the senescence process. Taken together, these data are correlated to the possible genetical aspects implied in this process, reviewing the most relevant results on senescence and cellular death obtained from yeast, fruit fly and nematodes; besides this, a brief review of the molecular biology of gerontogenes was carried out, and the possible mechanisms inducing aging and neurodegenerative processes are analyzed according to the state-of-the-art related theories. Finally, cellular, biochemical and genetical data are correlated in the signal transduction way implied in the increase of the intracellular calcium level as the starting point of cell death. CONCLUSIONS: The main process implied in the neuronal cell death responsible for aging and the related neurodegenerative diseases are started by different agents such as the lacking of neurotrophic factors, hypoxia, hypoglycemia, excitotoxicity, and oxygen and nitrogen free radicals.


Assuntos
Envelhecimento/fisiologia , Encéfalo/fisiologia , Doenças Neurodegenerativas/fisiopatologia , Animais , Apoptose , Encéfalo/citologia , Cálcio/metabolismo , Morte Celular , Metabolismo Energético , Radicais Livres , Hemostasia , Humanos , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/genética , Óxido Nítrico/fisiologia , Estresse Oxidativo/fisiologia , Receptores de Glutamato
20.
Reprod Sci ; 19(3): 243-52, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22383776

RESUMO

Differences in gene expression and imprinting have been reported, comparing in vivo versus in vitro generated preimplantation embryos. Furthermore, mouse studies have shown that placenta development is altered following in vitro culture. However, the molecular mechanisms underlying these findings are unknown. We therefore isolated trophectoderm (TE) and inner cell mass (ICM) cells from in vivo and in vitro fertilization (IVF) embryos and evaluated their transcriptome using microarrays. We found that the transcriptomes of in vitro produced ICM and TE cells showed remarkably few differences compared to ICM and TE cells of in vivo generated embryos. In vitro fertilization embryos showed a reduced number of TE cells compared to in vivo embryos. In addition, TE of IVF embryos showed significant downregulation of solute transporter genes and of genes involved in placenta formation (Eomesodermin, Socs3) or implantation (Hbegf). In summary, IVF and embryo culture significantly affects the transcriptome of ICM and TE cells.


Assuntos
Massa Celular Interna do Blastocisto/metabolismo , Ectogênese , Proteínas Fetais/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Trofoblastos/metabolismo , Animais , Proteínas Fetais/genética , Camundongos , Camundongos Endogâmicos
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