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1.
BMC Genet ; 16: 93, 2015 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-26219465

RESUMO

BACKGROUND: The global burden of chronic liver disease is rising. Besides environmental, behavioral, viral and metabolic factors, genetic polymorphisms in patatin-like phospholipase-3 (PNPLA3) and vitamin D receptor (VDR) genes have been related to the development of chronic liver disease and progression towards liver cancer. Although their prevalence differs remarkably among ethnic groups, the frequency of these polymorphisms in South American populations -whose genetic background is highly admixed- has been poorly studied. Hence, the aim of this study was to characterize polymorphisms related to chronic liver disease and their association with the genetic ancestry of South American populations. RESULTS: DNA samples from 258 healthy unrelated male volunteers were analyzed. The frequencies of G and C alleles of rs738409 polymorphism (PNPLA3 gene) were 74 % and 26 %, respectively; whereas the bAt (CCA) haplotype (VDR gene) was observed in 32.5 % of the samples. The GG genotype of PNPLA3 rs738409 and the bAt (CCA) haplotype -associated with an increased risk of chronic liver disease and progression towards liver cancer- were significantly more frequent among samples exhibiting maternal and paternal Native American haplogroups (63.7 % and 64.6 %), intermediate among admixed samples (45.1 % and 44.9 %; p = 0.03) and the lowest for Non-native American ancestry (30.1 % and 29.6 %; p = 0.001 and p = 0.0008). CONCLUSIONS: These results suggest that individuals with Native American ancestry might have a high risk of chronic liver disorders and cancer. Furthermore, these data not only support the molecular evaluation of ancestry in multi-ethnic population studies, but also suggest that the characterization of these variants in South American populations may be useful for establishing public health policies aimed at high risk ethnic communities.


Assuntos
Etnicidade/genética , Predisposição Genética para Doença , Hepatopatias/epidemiologia , Hepatopatias/etiologia , Polimorfismo Genético , Alelos , Doença Crônica , Frequência do Gene , Genótipo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Prevalência , Risco , Fatores de Risco , América do Sul/epidemiologia , América do Sul/etnologia
2.
Glycobiology ; 22(3): 411-6, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22038478

RESUMO

It is known that disialic acids (diSia) are present in the mammalian brain. However, the precise anatomical distribution and the chronology of its expression along life are not well studied yet. It is accepted that the transfer of diSia in the brain is mediated mainly by the enzyme ST8Sia III (α2,8-sialyltransferase III). We studied the expression of diSia glycoepitopes and of the ST8Sia III gene in different structures of the mouse brain at different postnatal stages by immunohistochemistry and real-time polymerase chain reaction, respectively. C57BL/6 mice of different stages were used. Samples of hippocampus, olfactory bulb, cortex and cerebellum were processed for studies of molecular biology and immunohistochemistry. Histological analysis revealed an important decrease in diSia labeling in the senile cerebellum compared with other structures and stages (P â‰ª 0.001). In concordance with these results, a significant decrease in ST8Sia III gene expression was found in the cerebellum of senile animals (P < 0.001). These results suggest that diSia are constantly expressed but with differential expression in various areas of the mouse central nervous system. On the other hand, the concordance in the decreased expression of ST8Sia III and the diSia epitope in the cerebellum of senile animals suggest a role of diSia in this structure or, inversely, an influence of aging on the expression of diSia in the cerebellum. Further research in that direction could elucidate the roles of diSia in brain function in health and disease.


Assuntos
Encefalopatias/metabolismo , Cerebelo/metabolismo , Regulação da Expressão Gênica , Ácidos Siálicos/metabolismo , Sialiltransferases/metabolismo , Animais , Cerebelo/enzimologia , Cerebelo/patologia , Hipocampo/enzimologia , Hipocampo/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Bulbo Olfatório/enzimologia , Bulbo Olfatório/metabolismo , Especificidade de Órgãos , Ácidos Siálicos/biossíntese , Sialiltransferases/genética
3.
J Integr Neurosci ; 11(1): 1-15, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22744780

RESUMO

In order to have a tool to empirically test the ideas derived from a theoretical model, we extended a protocol for evaluation of episodic-like memory in rats, based on the triad "what, where, context" for definition of memories. As with the computational model, our intention was for the animal being tested to store a specific number of object-place-context configurations as different memories, which would then be retrievable from cues. The aim of this work was to evaluate the influence of the number of configurations to be memorized on the performance of the task. Sixty-five Wistar male rats were evaluated. In accordance with previous work, for two configurations, the recognition index was indicative of recognition of the element mismatching the original memory (mean = 0.28; SEM = 0.12). The recognition index for three configurations was lower (mean = 0.15; SEM = 0.10), evidencing less recall with increasing requirements. The results also showed a trend toward recognition of novelty for the first and the last memory when evaluating three configurations (a "U" shape in the exploratory preference's curve), showing the primacy and recency effects typical of memory both in humans and animals. Nonetheless, the data presented a high inter-subject variability which makes the test non-robust for small groups. However, if used before and after a treatment for a same subject, we suggest that the protocol presented in this work can be a useful behavioral test for the evaluation of episodic-like memory in rats in terms of a variable task demand.


Assuntos
Pesquisa Comportamental/métodos , Hipocampo/fisiologia , Memória Episódica , Animais , Masculino , Ratos , Ratos Wistar
4.
Acta Gastroenterol Latinoam ; 42(1): 64-72, 2012 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-22616502

RESUMO

Pharmacogenomics is the study of genetic variations that produce a modification of the response to drugs. These variations are expressed as a different capacity for the metabolism or the transport of drugs, or a variable activity of drug receptors. Drug use in gastroenterology offers different examples of the use of pharmacogenomic analysis in the identification of the appropriate drug and drug dose for each individual patient. The use of proton pump inhibitors in the treatment of gastroesophagic reflux disease and Helicobacter pylori eradication may be optimized by the analysis of polymorphisms of the CYP2C19 gene. Additionally, the study of variants of IL28 helps in the identification of patients with more chances of response to the treatment of hepatitis C with interferon and ribavirin. The analysis of polymorphisms of the gene coding for the enzyme thiopurine methyl transferase (TPMT) helps in the reduction of the risks associated with the use of azathioprine in the treatment of inflammatory bowel disease. In this way, pharmacogenomics constitute not only a therapeutic tool that already shows an impact in the individualization of drug use in gastroenterology but also a tool with a great projection in the future.


Assuntos
Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/genética , Polimorfismo Genético , Humanos
5.
Pediatr Transplant ; 15(5): 525-32, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21711429

RESUMO

TAC, MMF and MP are used in pediatric kidney tx. The cytochrome P450 (CYP)3A5 enzyme appears to play a role in TAC metabolism. The aims of this study were to investigate CYP3A5 polymorphism's effect on TAC dosing and the age dependency of TAC dosing by testing blood concentrations, and the interaction between steroids and TAC during the first year after tx. Genomic DNA was extracted and amplified with specific primers. CYP3A5 alleles were confirmed by direct sequencing of PCR products on an automated AB13100 capillary sequencer. We studied 48 renal transplant patients (age at tx 12±0.5yr, 22 boys) receiving TAC, MMF, MP. Of these, 79% were CYP3A5*3/*3 (non-expressers homozygotes) and 21% were CYP3A5*1/*3 (expressers). TAC trough levels were 7.1±0.4ng/mL in CYP3A5*3/*3 patients and 6.5±0.7ng/mL in CYP3A5*1/*3 group (p=0.03). CYP3A5*1/*3 patients had lower levels of dose-adjusted TAC (36.7±5.8ng/mL/mg/kg/day) to achieve target blood concentration and required higher daily dose per weight (0.21±0.03mg/kg/day) than CYP3A5*3/*3 patients, 72.4±8.0ng/mL/mg/kg/day and 0.13±0.01mg/kg/day (p<0.001). Prepubertal patients with different CYP3A5 polymorphisms required significant higher TAC doses and achieved lower dose-normalized concentration compared with pubertal patients. Both TAC dose and adjusted-dose correlated with daily MP dose in CYP3A5*1*3 (r: 0.4, p<0.03 and r: 0.4, p<0.03) and in CYP3A5*3*3 (r: 0.6, p<0.01 and r: 0.47, p<0.001) patients. CYP3A5 polymorphism performed before tx could contribute to a better individualization of TAC therapy. The higher TAC dose in prepubertal patients and the pharmacological interactions between MP and TAC may not be fully explained by different CYP3A5 polymorphisms.


Assuntos
Citocromo P-450 CYP3A/genética , Transplante de Rim/métodos , Polimorfismo Genético , Tacrolimo/sangue , Tacrolimo/uso terapêutico , Adolescente , Fatores Etários , Peso Corporal , Criança , Primers do DNA/genética , Feminino , Homozigoto , Humanos , Masculino , Metilprednisolona/uso terapêutico , Ácido Micofenólico/análogos & derivados , Ácido Micofenólico/uso terapêutico , Esteroides , Resultado do Tratamento
6.
Medicina (B Aires) ; 71(4): 390-6, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-21893459

RESUMO

The mechanisms of epigenetic regulation play an important role in the development and function of body systems. Failure in the maintenance of this regulation as well as environmental factors could contribute to the development of multiple diseases in genetically predisposed patients. Although the molecular mechanisms responsible for the etiology of most diseases are unknown, there is evidence of both genetic and environmental factors that could influence this development. Recent findings involve epigenetic mechanisms in the origin of various diseases. This review aims to describe in detail the mechanisms of epigenetic regulation and the known findings involving the dysfunction of these mechanisms as a possible cause of various diseases.


Assuntos
Epigenômica , Predisposição Genética para Doença/genética , Doenças do Sistema Nervoso/genética , Exposição Ambiental , Humanos , Doenças do Sistema Nervoso/terapia
7.
Medicina (B Aires) ; 71(3): 267-73, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-21745780

RESUMO

Type 1 diabetes is an autoimmune disease of unknown etiology characterized by destruction of pancreatic beta cells, leading to absolute insulin deficiency. Standard therapy includes the use of exogenous insulin. However, due to the difficulty to achieve a tight metabolic control, a number of patients will present severe complications, including vascular, renal and ophthalmologic disease. On the other hand, a more strict metabolic control is often associated with episodes of life threatening hypoglycemia. This motivated the research and development of new alternative treatments, such as the transplantation of insulin producing beta cells, obtained from cadaveric pancreatic islets. Best results with this therapy were observed with consecutive islet injection from more than one donor and immunosuppressive therapy without steroids. However, the scarcity of organs as well as an increased immune reaction derived from the use of pancreas from different donors have limited this therapy to markedly selected patients and highly experienced centers. Furthermore, lifelong administration of immunosuppressive drugs may produce undesired secondary effects. Regenerative medicine opens the possibility of using stem cells capable of differentiating into insulin-producing cells after stimulation by diverse trophic factors that may act over stem cells located within a specific tissue.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Transplante de Células-Tronco Mesenquimais/métodos , Humanos
8.
Acta Gastroenterol Latinoam ; 41(3): 247-61, 2011 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-22233005

RESUMO

Genetic and epigenetic influences as well as dietary factors play an important role in the initiation and progression of cancer. More specifically, colorectal cancer (CRC) is influenced by dietary habits and it has been established that genetic and epigenetic changes are involved in the carcinogenesis. Within the CRC are hereditary syndromes (hereditary nonpolyposis colorectal cancer and familial adenomatous polyposis), which present germ line mutations on specific genes like hMLH1 and also changes on promoter's methylation, and sporadic cases, where the environment and individual's habits, both major components of epigenetics, partly define the initiation and development of cancer. Therefore the epigenetic is established as another way of carcinogenesis. Identify the factors that would predict the beginning of CRC is critical, as it is a rather silent disease which is observed clinically at an advanced stage.


Assuntos
Neoplasias Colorretais/genética , Epigênese Genética , Polipose Adenomatosa do Colo/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Inibidor de Quinase Dependente de Ciclina p57/genética , Ácido Fólico/metabolismo , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like II/genética , Fator 1 de Ligação ao Facilitador Linfoide/genética , Mutação/genética
9.
Gene Expr ; 14(6): 307-19, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20635573

RESUMO

The nervous system (NS) has a limited self-repair capability and adult neurogenesis is limited to certain regions of the brain. This generates a great interest in using stem cells to repair the NS. Previous reports have shown the differentiation of adipose tissue-derived mesenchymal stem cells (ASCs) in neuron-like cells when cultures are enriched with growth factors participating in embryonic and adult neurogenesis. Therefore, it could be thought that there exists a functional parallelism between neurogenesis and neuronal differentiation of ASCs. For this reason, the goal of this work was to study the differential gene expression of Shh and BMP genetic pathways involved in cell fate determination and proliferation. In this study we demonstrated that hASCs are endowed with active Hedgehog and BMP signaling pathways through the expression of genes of both cascades and that their expressions are downregulated after neuronal induction. This idea is in accordance with the facts that Shh and BMP signaling is involved in the maintenance of cells with stem cells properties and that proliferation decreases during the process of differentiation. Furthermore, Noggin expression was detected in induced hASCs whereas there was no expression in noninduced cells, which indicates that these cells are probably adopting a neuronal fate because noggin diverts neural stem cells from glial to neuronal fate. We also detected FM1-43 and synaptophisin staining, which is evidence of the presence of putative functional presynaptic terminals, a neuron-specific property. These results could partially contribute to the elucidation of the molecular mechanisms involved in neuronal differentiation of adult human nonneural tissues.


Assuntos
Tecido Adiposo/citologia , Proteínas Morfogenéticas Ósseas/genética , Transdiferenciação Celular/fisiologia , Regulação da Expressão Gênica/fisiologia , Proteínas Hedgehog/genética , Células-Tronco Mesenquimais/citologia , Neurônios/citologia , Tecido Adiposo/metabolismo , Adulto , Linhagem da Célula , Células Cultivadas , Endocitose/fisiologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Técnicas In Vitro , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Neurônios/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/fisiologia , Vesículas Sinápticas/metabolismo
10.
Medicina (B Aires) ; 70(2): 185-93, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-20447905

RESUMO

Clinical depression is a physical and psychic disease that has neuropathological basis, although the clear understanding of its ethiopathology is still missing. There is evidence of a genetic component in depression, however, the participation of environment is crucial. Stress plays an essential role in the onset of depression. The interaction and the response of the endocrine system with the immune and nervous system are altered in depression. The observation of the effect of antidepressants on monoaminergic transmitters leads to the hypothesis of monoamines. However this hypothesis cannot explain many of the mechanisms involved in the action of antidepressants. The new hypothesis proposed to explain the action of antidepressant is the neuro-plasticity hypothesis. This hypothesis suggests that the effects of antidepressants on nervous, immune and endocrine systems are able to induce neuroadaptative changes in the brain. The neuroplasticity have been described as the ability of the brain to reorganize itself and form new neuronal connections throughout life. It is proposed that antidepressants influence neuroplasticity inducing improvements in the symptoms of this illness.


Assuntos
Depressão/fisiopatologia , Plasticidade Neuronal/fisiologia , Antidepressivos/uso terapêutico , Monoaminas Biogênicas/fisiologia , Depressão/tratamento farmacológico , Depressão/imunologia , Humanos , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/imunologia
11.
Medicina (B Aires) ; 70(6): 537-42, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-21163745

RESUMO

Current prenatal diagnosis of monogeneic and chromosomal diseases, includes invasive procedures which carry a small but significant risk. For many years, analysis of fetal cells in maternal circulation has been studied, however it has failed its clinical use due to the scarcity of these cells and their persistance after delivery. For more than a decade, the presence of cell-free fetal DNA in maternal blood has been identified. These fetal DNA fragments would derive from the placenta and are not detected after delivery, making them a source of fetal material for carrying out diagnosis techniques using maternal blood. However, the vast majority of cell free DNA in maternal circulation is of maternal origin, with the fetal component contributing from 3% to 6% and rising towards term. Available methodologies do not allow separation of fetal from maternal cell free DNA, so current applications have been focused on the analysis of genes not present in the mother, such as Y chromosome sequences, or RHD gene in RhD-negative women, or paternal or de novo mutations. Also, the detection of cell-free fetal RNA in maternal blood offers the possibility of obtaining information regarding genetic expression profiles of embrionic tissues, and using genes expressed only at the feto-placental unit, controls for the presence of fetal material could be established, regardless of maternal genetic tissue. The present article describes the evidences regarding the passage of fetal nucleic acids to maternal circulation, its current prenatal diagnosis application and possible future perspectives.


Assuntos
DNA/sangue , Feto/química , Troca Materno-Fetal/genética , Diagnóstico Pré-Natal/métodos , Sistema Livre de Células , Feminino , Doenças Genéticas Inatas/diagnóstico , Humanos , Gravidez , RNA/sangue , Sistema do Grupo Sanguíneo Rh-Hr , Análise para Determinação do Sexo/métodos
12.
Cell Biol Int ; 33(11): 1196-200, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19703574

RESUMO

Stem cells were derived from hatched blastocyst-stage mouse embryos of the C57BL/6 strain employing a knockout serum replacement instead of the traditional fetal calf serum, thereby avoiding the use of immunosurgery. Although fetal calf serum was not good for isolation of stem cells, a combination of this serum plus knockout serum increased the expansion rate of the cell culture. The derived cells were capable of maintaining an undifferentiated state during several passages, as demonstrated by the presence of alkaline phosphatase activity, stage-specific embryonic antigen 1 (SSEA-1), and octamer binding protein 4 (Oct-4). Suspension culture in bacteriological dishes gave better results than the hanging drop method for differentiation by means of embryoid body formation. Mouse embryonic stem cells showed spontaneous differentiation into derivatives of the 3 germ layers in culture media supplemented with fetal calf serum but not with knockout serum.


Assuntos
Técnicas de Cultura de Células , Diferenciação Celular , Separação Celular/métodos , Células-Tronco Embrionárias/citologia , Animais , Blastocisto/citologia , Meios de Cultura , Células-Tronco Embrionárias/metabolismo , Antígenos CD15/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mórula , Fator 3 de Transcrição de Octâmero/metabolismo
13.
Learn Mem ; 14(4): 295-303, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17522018

RESUMO

The reconsolidation hypothesis states that a consolidated memory could again become unstable and susceptible to facilitation or impairment for a discrete period of time after a reminder presentation. The phenomenon has been demonstrated in very diverse species and types of memory, including the human procedural memory of a motor skill task but not the human declarative one. Here we provide evidence for both consolidation and reconsolidation in a paired-associate learning (i.e., learning an association between a cue syllable and the respective response syllable). Subjects were given two training sessions with a 24-h interval on distinct verbal material, and afterward, they received at testing two successive retrievals corresponding to the first and second learning, respectively. Two main results are noted. First, the first acquired memory was impaired when a reminder was presented 5 min before the second training (reconsolidation), and also when the second training was given 5 min instead of 24 h after the first one (consolidation). Second, the first retrieval proved to influence negatively on the later one (the retrieval-induced forgetting [RIF] effect), and we used the absence of this RIF effect as a very indicator of the target memory impairment. We consider the demonstration of reconsolidation in human declarative memory as backing the universality of this phenomenon and having potential clinical relevance. On the other hand, we discuss the possibility of using the human declarative memory as a model to address several key topics of the reconsolidation hypothesis.


Assuntos
Memória , Aprendizagem por Associação de Pares , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Rememoração Mental , Fatores de Tempo
14.
Acta Gastroenterol Latinoam ; 36(2): 66-75, 2006 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-16859079

RESUMO

Hepatocytes are epithelial cells that show a complex polarity in vivo. However, hepatocytes isolated and cultured in vitro normally lose both their differentiated properties and polarity. Culturing hepatocyte spheroids seems to be the accurate approach to maintain tissue level of organization. The structural and functionalpolarities of pig liver spheroids were analyzed in this work. Swine liver cells were isolated and cultured as spheroids. Their metabolic activity was proved through the metabolism of diazepam, ammonium and synthesis of albumin. Several structural features show the presence of polarity in the cells inside the spheroids. Reticular and collagen fibers, as well as Ck19(+) cells forming duct-like structures were found. _eta and _-catenins and pancadherins were positive in different regions of the spheroids, mainly in the outer cell layers, which have cuboidal epithelia features. The scanning electron microscopy showed a tightly compacted architecture, with smooth surface. The transmission electron microscopy analysis showed bile canaliculi with microvilli, tight junctions, zonula adherens and desmosome-like junctions. Well-maintained cellular organelles, as mitochondria, nucleus, nucleolus, peroxisomes, endoplasmic reticulum, were seen in the spheroids. A complex inner bile canaliculi network was shown by using a fluorescent bile acid analogue incorporated and excreted by the spheroids. Furthermore, excretion of a normal pattern of bile acids was demonstrated. The morphology and functionality of the spheroids may provide an appropriate model for applications where the maintenance of liver-specific functions is crucial, as a bioartificial liver device.


Assuntos
Polaridade Celular/fisiologia , Hepatócitos/citologia , Esferoides Celulares/citologia , Albuminas/metabolismo , Animais , Diazepam/metabolismo , Hepatócitos/fisiologia , Esferoides Celulares/fisiologia , Suínos , Ureia/metabolismo
15.
Front Behav Neurosci ; 10: 105, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27375445

RESUMO

In eusocial insects, experiences acquired during the development have long-term consequences on mature behavior. In the honeybee that suffers profound changes associated with metamorphosis, the effect of odor experiences at larval instars on the subsequent physiological and behavioral response is still unclear. To address the impact of preimaginal experiences on the adult honeybee, colonies containing larvae were fed scented food. The effect of the preimaginal experiences with the food odor was assessed in learning performance, memory retention and generalization in 3-5- and 17-19 day-old bees, in the regulation of their expression of synaptic-related genes and in the perception and morphology of their antennae. Three-five day old bees that experienced 1-hexanol (1-HEX) as food scent responded more to the presentation of the odor during the 1-HEX conditioning than control bees (i.e., bees reared in colonies fed unscented food). Higher levels of proboscis extension response (PER) to 1-HEX in this group also extended to HEXA, the most perceptually similar odor to the experienced one that we tested. These results were not observed for the group tested at older ages. In the brain of young adults, larval experiences triggered similar levels of neurexins (NRXs) and neuroligins (Nlgs) expression, two proteins that have been involved in synaptic formation after associative learning. At the sensory periphery, the experience did not alter the number of the olfactory sensilla placoidea, but did reduce the electrical response of the antennae to the experienced and novel odor. Our study provides a new insight into the effects of preimaginal experiences in the honeybee and the mechanisms underlying olfactory plasticity at larval stage of holometabolous insects.

16.
Neurol Res ; 38(1): 25-31, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26905484

RESUMO

INTRODUCTION: Cerebrospinal fluid (CSF) leaks are a common complication after cranial and spinal surgery and are associated with increased morbidity. Despite continuous research in this field, this problem is far from solved. In this paper, we describe the construction and testing of a bacterial cellulose (BC) membrane as a new dural patch. MATERIALS AND METHODS: The synthesis of BC was performed using Gluconacetobacter hansenii (ATCC 23769) and films were sterilized by autoclaving. The membranes were seeded with human dural fibroblasts. Growth, shape, and cell viability were assessed after 4 weeks. RESULTS: Normally shaped fibroblasts were seen on the BC grafts; confocal microscopy showed cells inside the structure of the mesh. Both viable and nonviable cells were present. Cellular attachment and viability were confirmed by replating of the membranes. DISCUSSION: BC membranes are used in clinical practice to improve skin healing. In the presence of water, they form an elastic, nontoxic, and resistant biogel that can accommodate collagen and growth factors within their structure, thus BC is a good candidate for dural graft construction.


Assuntos
Membrana Celular/metabolismo , Celulose/metabolismo , Dura-Máter/metabolismo , Fibroblastos/fisiologia , Membrana Celular/ultraestrutura , Sobrevivência Celular , Celulose/ultraestrutura , Vazamento de Líquido Cefalorraquidiano/patologia , Dura-Máter/efeitos da radiação , Dura-Máter/ultraestrutura , Fibroblastos/ultraestrutura , Humanos , Técnicas In Vitro , Microscopia Eletrônica de Varredura , Técnicas de Cultura de Órgãos , Termogravimetria , Fatores de Tempo , Vimentina/metabolismo , Raios X
17.
J Psychiatr Res ; 63: 105-16, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25819500

RESUMO

The amygdala is innervated by the cholinergic system and is involved in major depressive disorder (MDD). Evidence suggests a hyper-activate cholinergic system in MDD. Hippocampal Cholinergic Neurostimulating Peptide (HCNP) regulates acetylcholine synthesis. The aim of the present work was to investigate expression levels of HCNP-precursor protein (HCNP-pp) mRNA and other cholinergic-related genes in the postmortem amygdala of MDD patients and matched controls (females: N = 16 pairs; males: N = 12 pairs), and in the mouse unpredictable chronic mild stress (UCMS) model that induced elevated anxiety-/depressive-like behaviors (females: N = 6 pairs; males: N = 6 pairs). Results indicate an up-regulation of HCNP-pp mRNA in the amygdala of women with MDD (p < 0.0001), but not males, and of UCMS-exposed mice (males and females; p = 0.037). HCNP-pp protein levels were investigated in the human female cohort, but no difference was found. There were no differences in gene expression of acetylcholinesterase (AChE), muscarinic (mAChRs) or nicotinic receptors (nAChRs) between MDD subjects and controls or UCMS and control mice, except for an up-regulation of AChE in UCMS-exposed mice (males and females; p = 0.044). Exploratory analyses revealed a baseline expression difference of cholinergic signaling-related genes between women and men (p < 0.0001). In conclusion, elevated amygdala HCNP-pp expression may contribute to mechanisms of MDD in women, potentially independently from regulating the cholinergic system. The differential expression of genes between women and men could also contribute to the increased vulnerability of females to develop MDD.


Assuntos
Tonsila do Cerebelo/metabolismo , Transtorno Depressivo Maior/patologia , Neuropeptídeos/genética , RNA Mensageiro/metabolismo , Regulação para Cima/fisiologia , Acetilcolinesterase/metabolismo , Adulto , Análise de Variância , Animais , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neuropeptídeos/metabolismo , Mudanças Depois da Morte , Receptores Muscarínicos/genética , Receptores Muscarínicos/metabolismo , Fatores Sexuais , Estresse Psicológico/patologia , Adulto Jovem
18.
Psychiatry Res ; 229(1-2): 580-2, 2015 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-26239769

RESUMO

ASD might be associated with alterations in excitation/inhibition ratio and GABA(A) has been implicated since it mediates synaptic inhibition. Polymorphisms in GABA receptor (GABAR) were studied: significant differences in allele and genotype frequencies observed between cases and controls (rs1912960, GABRA4). Haplotype analysis: rs1912960 (GABRA4) and rs211037 (GABRG2) overrepresented in cases. Rs1912960 has been associated with ASD and rs211037 with epilepsy. GABRA4 is associated with autism in the Argentinean dataset independently or in combination with GABRG2.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/genética , Estudos de Associação Genética/métodos , Polimorfismo de Nucleotídeo Único/genética , Receptores de GABA-A/genética , Argentina/epidemiologia , Transtorno do Espectro Autista/epidemiologia , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença/genética , Haplótipos/genética , Humanos , Masculino , Subunidades Proteicas/genética
19.
Neurol Res ; 37(10): 867-73, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26104574

RESUMO

OBJECTIVE: Post-operative meningitis, caused mainly by Staphylococcus aureus and Gram-negative rods, is a life-threatening complication after neurosurgery, and its pathogenesis is far from clear. The purpose of this work was to study the experimental infection of human dura-mater fibroblasts and whole human dura by S. aureus. METHODS: In vitro cultures of human dura-mater fibroblasts and organotypic cultures of small pieces of human dura mater were inoculated with a human-derived S. aureus strain. The pattern of bacterial infection as well as cytokines secretion by the infected fibroblasts was studied. RESULTS: Our results suggest that colonisation of human dura-mater fibroblasts in culture and whole dura-mater tissue by S. aureus includes bacterial growth on the cell surface, fibroblast intracellular invasion by bacteria and a significant synthesis of interleukin 1beta (IL-1beta) by the infected cells. CONCLUSION: This is the first report of human dura-mater fibroblast infection by S. aureus. Hopefully, these results can lead to a better understanding of the pathogenesis of meningitis caused by this bacterial species and to a more rational therapeutic approach.


Assuntos
Dura-Máter/microbiologia , Fibroblastos/microbiologia , Infecções Estafilocócicas/metabolismo , Células Cultivadas , Dura-Máter/metabolismo , Dura-Máter/ultraestrutura , Fibroblastos/metabolismo , Fibroblastos/ultraestrutura , Humanos , Técnicas In Vitro , Interleucina-1beta/metabolismo , Técnicas de Cultura de Órgãos , Staphylococcus aureus/ultraestrutura
20.
Cell Transplant ; 13(1): 61-5, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15040606

RESUMO

Here we report on the impact of completely unpurified islet transplantation on the portal vein pressure (PVP) and the hepatic biochemistry in the peritransplant period and on follow-up. Type I diabetic patients underwent simultaneous kidney and islet transplantation. Islets were not purified from the acinar tissue to prevent loss of endocrine mass. Each patient received a mean 521,846 +/- 201,539.4 islet equivalents (7812.1 islet equivalents/kg/recipient). Immunosuppression and peritransplant medication were given according to the Giessen protocol. The islets were injected into the left hepatic lobe through the umbilical vein. PVP was recorded at time 0 and every 5 min throughout cell infusion. Liver function was assessed daily for the first 10 days, and on follow-up. Basal, peak, and final PVP were 12 +/- 3.8, 25.1 +/- 7.9, and 19.5 +/- 6.2 mmHg, respectively (basal vs. final, p < 0.05). Bilirubin, alkaline phosphatase, prothrombin time, and APTT stayed within normal range. Peak aspartate aminotransferase (AST), alanine aminotransferase (ALT), and serum amylase were 109.4 +/- 61.2 IU/L (basal vs. peak, not significant), 79.5 +/- 56.9 IU/L (basal vs. peak, not significant), and 887.5 +/- 153.6 IU/L (basal vs. peak, p = 0.02), respectively. In all cases AST, ALT, and amylase normalized within 6 days posttransplant and remained so on follow-up (longest control, 33 months posttransplant). Although the intrahepatic infusion of unpurified pancreatic islets affects both the portal vein pressure and the hepatic biochemical profile, this effect is transient and does not compromise the safety of the procedure.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/citologia , Transplante de Rim/métodos , Fígado/metabolismo , Veia Porta/fisiopatologia , Adulto , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Pressão Sanguínea , Cadáver , Nefropatias Diabéticas/cirurgia , Feminino , Humanos , Isquemia , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Pâncreas/anatomia & histologia , Período Pós-Operatório , Doadores de Tecidos
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