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1.
Mol Hum Reprod ; 29(2)2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36637195

RESUMO

Increasingly, couples struggling with fertility turn to assisted reproductive techniques, including IVF, to have children. Despite the demonstrated influence of periconception male health and lifestyle choices on offspring development, studies examining IVF success rates and child health outcomes remain exclusively focused on maternal factors. Using a physiologically relevant mouse model, we tested the hypothesis that chronic paternal preconception alcohol intake adversely affects IVF success and negatively impacts IVF offspring fetoplacental growth. Using a voluntary, binge-like mouse model, we exposed sexually mature C57BL/6J males to three preconception treatments (0% (Control), 6% EtOH or 10% EtOH) for 6 weeks, isolated and cryopreserved caudal sperm from treated males, and then used these samples to fertilize oocytes before assessing IVF embryo developmental outcomes. We found that preconception paternal alcohol use reduced IVF embryo survival and pregnancy success rates in a dose-dependent manner, with the pregnancy success rate of the 10% EtOH treatment falling to half those of the Controls. Mechanistically, we found that preconception paternal alcohol exposure disrupts embryonic gene expression, including Fgf4 and Egfr, two critical regulators of trophectoderm stem cell growth and placental patterning, with lasting impacts on the histological organization of the late-term placenta. The changes in placental histoarchitecture were accompanied by altered regulation of pathways controlling mitochondrial function, oxidative phosphorylation and some imprinted genes. Our studies indicate that male alcohol use may significantly impede IVF success rates, increasing the couple's financial burden and emotional stress, and highlights the need to expand prepregnancy messaging to emphasize the reproductive dangers of alcohol use by both parents.


Assuntos
Etanol , Fertilização in vitro , Exposição Paterna , Taxa de Gravidez , Animais , Feminino , Masculino , Camundongos , Gravidez , Camundongos Endogâmicos C57BL , Placenta , Sêmen , Etanol/efeitos adversos
2.
FASEB J ; 35(12): e22035, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34748230

RESUMO

Epigenetic mechanisms of paternal inheritance are an emerging area of interest in our efforts to understand fetal alcohol spectrum disorders. In rodent models examining maternal alcohol exposures, different maternal genetic backgrounds protect or sensitize offspring to alcohol-induced teratogenesis. However, whether maternal background can mitigate sperm-inherited alterations in developmental programming and modify the penetrance of growth defects induced by preconception paternal alcohol exposures remains unaddressed. In our previous studies examining pure C57Bl/6J crosses, the offspring of alcohol-exposed sires exhibited fetal growth restriction, enlarged placentas, and decreased placental efficiency. Here, we find that in contrast to our previous studies, the F1 offspring of alcohol-exposed C57Bl/6J sires and CD-1 dams do not exhibit fetal growth restriction, with male fetuses developing smaller placentas and increased placental efficiencies. However, in these hybrid offspring, preconception paternal alcohol exposure induces sex-specific changes in placental morphology. Specifically, the female offspring of alcohol-exposed sires displayed structural changes in the junctional and labyrinth zones, along with increased placental glycogen content. These changes in placental organization are accompanied by female-specific alterations in the expression of imprinted genes Cdkn1c and H19. Although male placentae do not display overt changes in placental histology, using RNA-sequencing, we identified programmed alterations in genes regulating oxidative phosphorylation, mitochondrial function, and Sirtuin signaling. Collectively, our data reveal that preconception paternal alcohol exposure transmits a stressor to developing offspring, that males and females exhibit distinct patterns of placental adaptation, and that maternal genetic background can modulate the effects of paternal alcohol exposure.


Assuntos
Adaptação Fisiológica , Etanol/toxicidade , Transtornos do Espectro Alcoólico Fetal/patologia , Retardo do Crescimento Fetal/patologia , Herança Paterna , Penetrância , Placenta/fisiopatologia , Animais , Epigênese Genética , Feminino , Transtornos do Espectro Alcoólico Fetal/etiologia , Retardo do Crescimento Fetal/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Gravidez , Fatores Sexuais , Transcriptoma
4.
Inorg Chem ; 55(14): 6902-15, 2016 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-27347607

RESUMO

The syntheses and crystal structures of 16 new rare-earth (RE = La(3+)-Y(3+))-3,5-dichlorobenzoic acid-terpyridine molecular materials characterized via single-crystal and powder X-ray diffraction are reported. These 16 complexes consist of four unique structure types ranging from molecular dimers (La(3+) and Ce(3+)) to tetramers (Pr(3+)-Y(3+)) as one moves across the RE(3+) series. This structural evolution is accompanied by subsequent changes in modes of supramolecular assembly (halogen bonding, halogen-π, halogen-halogen, and π-π interactions). Solid-state visible and near-infrared lifetime measurements were performed on complexes 6 (Sm(3+)), 7 (Eu(3+)), 9 (Tb(3+)), 10 (Dy(3+)), 11 (Ho(3+)), 12 (Er(3+)), and 14 (Yb(3+)), and characteristic emission was observed for all complexes except 11. Lifetime data for 11, 12, and 14 suggest sensitization by the terpy antenna does occur in near-infrared systems, although not as efficiently as in the visible region. Additionally, direct current magnetic susceptibility measurements were taken for complexes 10 (Dy(3+)) and 12 (Er(3+)) and showed dominant ferromagnetic behavior.

5.
J Vet Dent ; : 8987564231161226, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36922766

RESUMO

The objective of this study was to evaluate owner assessment of appetite, demeanor, and mouth soreness following dental extractions in dogs receiving either bupivacaine hydrochloride (BH) or liposomal encapsulated bupivacaine (LEB) for dental blocks. Thirty healthy, adult dogs requiring dental extractions were enrolled in the study. All procedures were completed with dogs under general anesthesia. A non-steroidal anti-inflammatory drug was administered subcutaneously in the preoperative period. Dogs were randomly assigned to receive BH or LEB. An owner assessment to evaluate appetite, demeanor, and soreness of mouth was completed at the end of both the first and second day after discharge from the hospital. The total of the owner assessments for day 1 and both days combined was significantly lower for dogs receiving LEB (P = .007). There were no differences in the number of extractions (P = .21), time from block to evaluations (P = .07), in-hospital pain assessments (P = .99), or number of dogs requiring rescue analgesia (P = .99). This study concluded, dogs that received LEB for dental blocks had improved appetite and demeanor, and reduced soreness of mouth, as evaluated by the owner two days postoperatively, when compared to dogs who received BH.

6.
Andrology ; 2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38044754

RESUMO

BACKGROUND: Chronic preconception paternal alcohol use adversely modifies the sperm epigenome, inducing fetoplacental and craniofacial growth defects in the offspring of exposed males. A crucial outstanding question in the field of paternal epigenetic inheritance concerns the resilience of the male germline and its capacity to recover and correct sperm-inherited epigenetic errors after stressor withdrawal. OBJECTIVES: We set out to determine if measures of the sperm-inherited epigenetic program revert to match the control treatment 1 month after withdrawing the daily alcohol treatments. MATERIALS AND METHODS: Using a voluntary access model, we exposed C57BL/6J males to 6% or 10% alcohol for 10 weeks, withdrew the alcohol treatments for 4 weeks, and used RNA sequencing to examine gene expression patterns in the caput section of the epididymis. We then compared the abundance of sperm small RNA species between treatments. RESULTS: In the caput section of the epididymis, chronic alcohol exposure induced changes in the transcriptional control of genetic pathways related to the mitochondrial function, oxidative phosphorylation, and the generalized stress response (EIF2 signaling). Subsequent analysis identified region-specific, alcohol-induced changes in mitochondrial DNA copy number across the epididymis, which correlated with increases in the mitochondrial DNA content of alcohol-exposed sperm. Notably, in the corpus section of the epididymis, increases in mitochondrial DNA copy number persisted 1 month after alcohol cessation. Analysis of sperm noncoding RNAs between control and alcohol-exposed males 1 month after alcohol withdrawal revealed a ∼100-fold increase in mir-196a, a microRNA induced as part of the nuclear factor erythroid 2-related factor 2 (Nrf2)-driven cellular antioxidant response. DISCUSSION AND CONCLUSION: Our data reveal that alcohol-induced epididymal mitochondrial dysfunction and differences in sperm noncoding RNA content persist after alcohol withdrawal. Further, differences in mir-196a and sperm mitochondrial DNA copy number may serve as viable biomarkers of adverse alterations in the sperm-inherited epigenetic program.

7.
Epigenetics Chromatin ; 15(1): 2, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991687

RESUMO

BACKGROUND: Paternal lifestyle choices and male exposure history have a critical influence on the health and fitness of the next generation. Accordingly, defining the processes of germline programming is essential to resolving how the epigenetic memory of paternal experiences transmits to their offspring. Established dogma holds that all facets of chromatin organization and histone posttranslational modification are complete before sperm exits the testes. However, recent clinical and animal studies suggest that patterns of DNA methylation change during epididymal maturation. In this study, we used complementary proteomic and deep-sequencing approaches to test the hypothesis that sperm posttranslational histone modifications change during epididymal transit. RESULTS: Using proteomic analysis to contrast immature spermatozoa and mature sperm isolated from the mouse epididymis, we find progressive changes in multiple histone posttranslational modifications, including H3K4me1, H3K27ac, H3K79me2, H3K64ac, H3K122ac, H4K16ac, H3K9me2, and H4K20me3. Interestingly, some of these changes only occurred on histone variant H3.3, and most involve chromatin modifications associated with gene enhancer activity. In contrast, the bivalent chromatin modifications, H3K4me3, and H3K27me3 remained constant. Using chromatin immunoprecipitation coupled with deep sequencing, we find that changes in histone h3, lysine 27 acetylation (H3K27ac) involve sharpening broad diffuse regions into narrow peaks centered on the promoter regions of genes driving embryonic development. Significantly, many of these regions overlap with broad domains of H3K4me3 in oocytes and ATAC-seq signatures of open chromatin identified in MII oocytes and sperm. In contrast, histone h3, lysine 9 dimethylation (H3K9me2) becomes enriched within the promoters of genes driving meiosis and in the distal enhancer regions of tissue-specific genes sequestered at the nuclear lamina. Maturing sperm contain the histone deacetylase enzymes HDAC1 and HDAC3, suggesting the NuRD complex may drive some of these changes. Finally, using Western blotting, we detected changes in chromatin modifications between caput and caudal sperm isolated from rams (Ovis aries), inferring changes in histone modifications are a shared feature of mammalian epididymal maturation. CONCLUSIONS: These data extend our understanding of germline programming and reveal that, in addition to trafficking noncoding RNAs, changes in histone posttranslational modifications are a core feature of epididymal maturation.


Assuntos
Epididimo , Epigenoma , Animais , Cromatina/metabolismo , Metilação de DNA , Masculino , Camundongos , Herança Paterna , Proteômica , Espermatozoides/metabolismo
8.
Sci Rep ; 12(1): 8839, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35614060

RESUMO

Using a mouse model, studies by our group reveal that paternal preconception alcohol intake affects offspring fetal-placental growth, with long-lasting consequences on adult metabolism. Here, we tested the hypothesis that chronic preconception male alcohol exposure impacts histone enrichment in sperm and that these changes are associated with altered developmental programming in the placenta. Using chromatin immunoprecipitation, we find alcohol-induced increases in sperm histone H3 lysine 4 trimethylation (H3K4me3) that map to promoters and presumptive enhancer regions enriched in genes driving neurogenesis and craniofacial development. Given the colocalization of H3K4me3 with the chromatin binding factor CTCF across both sperm and embryos, we next examined CTCF localization in the placenta. We find global changes in CTCF binding within placentae derived from the male offspring of alcohol-exposed sires. Furthermore, altered CTCF localization correlates with dysregulated gene expression across multiple gene clusters; however, these transcriptional changes only occur in male offspring. Finally, we identified a correlation between genomic regions exhibiting alcohol-induced increases in sperm H3K4me3 and increased CTCF binding in male placentae. Collectively, our analysis demonstrates that the chromatin landscape of sperm is sensitive to chronic alcohol exposure and that a subset of these affected regions exhibits increased placental CTCF enrichment.


Assuntos
Etanol , Histonas , Lisina , Placenta , Fator de Ligação a CCCTC/metabolismo , Cromatina/metabolismo , Etanol/toxicidade , Feminino , Histonas/metabolismo , Humanos , Lisina/metabolismo , Masculino , Placenta/efeitos dos fármacos , Placenta/metabolismo , Gravidez , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo
9.
Front Cell Dev Biol ; 10: 930375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36036017

RESUMO

Hormesis refers to graded adaptive responses to harmful environmental stimuli where low-level toxicant exposures stimulate tissue growth and responsiveness while, in contrast, higher-level exposures induce toxicity. Although the intergenerational inheritance of programmed hormetic growth responses is described in plants and insects, researchers have yet to observe this phenomenon in mammals. Using a physiologically relevant mouse model, we demonstrate that chronic preconception paternal alcohol exposures program nonlinear, dose-dependent changes in offspring fetoplacental growth. Our studies identify an inverse j-shaped curve with a threshold of 2.4 g/Kg per day; below this threshold, paternal ethanol exposures induce programmed increases in placental growth, while doses exceeding this point yield comparative decreases in placental growth. In male offspring, higher paternal exposures induce dose-dependent increases in the placental labyrinth layer but do not impact fetal growth. In contrast, the placental hypertrophy induced by low-level paternal ethanol exposures associate with increased offspring crown-rump length, particularly in male offspring. Finally, alterations in placental physiology correlate with disruptions in both mitochondrial-encoded and imprinted gene expression. Understanding the influence of ethanol on the paternally-inherited epigenetic program and downstream hormetic responses in offspring growth may help explain the enormous variation observed in fetal alcohol spectrum disorder (FASD) phenotypes and incidence.

10.
Arthritis Rheum ; 62(5): 1469-77, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20131292

RESUMO

OBJECTIVE: Aicardi-Goutières syndrome (AGS) is an early-onset encephalopathy resembling congenital viral infection that is characterized by basal ganglia calcifications, loss of white matter, cerebrospinal fluid (CSF) lymphocytosis, and elevated interferon-alpha levels in the CSF. Studies have shown that AGS is an autosomal-recessive disease linked to mutations in 5 genes, encoding the 3'-repair DNA exonuclease 1 (TREX1), the 3 subunits of ribonuclease H2 (RNASEH2A-C), and sterile alpha motif domain and HD domain-containing protein 1 (SAMHD1). In this study we further characterized the phenotypic spectrum of this disease. METHODS: Clinical and laboratory data were obtained from 26 patients fulfilling the clinical diagnostic criteria for AGS. Genomic DNA was screened for mutations in all 5 AGS genes by direct sequencing, and sera were analyzed for autoantibodies. RESULTS: In 20 patients with AGS, 20 mutations, 12 of which were novel, were identified in all 5 AGS genes. Clinical and laboratory investigations revealed a high prevalence of features (some not previously described in patients with AGS) that are commonly seen in patients with systemic lupus erythematosus (SLE), such as thrombocytopenia, leukocytopenia, antinuclear antibodies, erythematous lesions, oral ulcers, and arthritis, which were observed in 12 (60%) of 20 patients with AGS. Moreover, the coexistence of AGS and SLE, was for the first time, demonstrated in 2 patients with molecularly proven AGS. CONCLUSION: These findings expand the phenotypic spectrum of lupus erythematosus in AGS and provide further insight into its disease mechanisms by showing that activation of the innate immune system as a result of inherited defects in nucleic acid metabolism could lead to systemic autoimmunity.


Assuntos
Doenças Autoimunes do Sistema Nervoso/genética , Encefalopatias/genética , Exodesoxirribonucleases/genética , Lúpus Eritematoso Sistêmico/genética , Proteínas Monoméricas de Ligação ao GTP/genética , Fosfoproteínas/genética , Ribonuclease H/genética , Adolescente , Adulto , Doenças Autoimunes do Sistema Nervoso/epidemiologia , Doenças Autoimunes do Sistema Nervoso/patologia , Encefalopatias/epidemiologia , Encefalopatias/patologia , Criança , Pré-Escolar , Distonia/epidemiologia , Distonia/genética , Feminino , Predisposição Genética para Doença/epidemiologia , Humanos , Lactente , Lúpus Eritematoso Sistêmico/epidemiologia , Lúpus Eritematoso Sistêmico/patologia , Imageamento por Ressonância Magnética , Masculino , Hipotonia Muscular/epidemiologia , Hipotonia Muscular/genética , Mutação de Sentido Incorreto , Fenótipo , Polimorfismo de Nucleotídeo Único , Prevalência , Proteína 1 com Domínio SAM e Domínio HD , Adulto Jovem
11.
Epigenetics Chromatin ; 14(1): 27, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130715

RESUMO

BACKGROUND: A critical question emerging in the field of developmental toxicology is whether alterations in chromatin structure induced by toxicant exposure control patterns of gene expression or, instead, are structural changes that are part of a nuclear stress response. Previously, we used a mouse model to conduct a three-way comparison between control offspring, alcohol-exposed but phenotypically normal animals, and alcohol-exposed offspring exhibiting craniofacial and central nervous system structural defects. In the cerebral cortex of animals exhibiting alcohol-induced dysgenesis, we identified a dramatic increase in the enrichment of dimethylated histone H3, lysine 9 (H3K9me2) within the regulatory regions of key developmental factors driving histogenesis in the brain. However, whether this change in chromatin structure is causally involved in the development of structural defects remains unknown. RESULTS: Deep-sequencing analysis of the cortex transcriptome reveals that the emergence of alcohol-induced structural defects correlates with disruptions in the genetic pathways controlling oxidative phosphorylation and mitochondrial function. The majority of the affected pathways are downstream targets of the mammalian target of rapamycin complex 2 (mTORC2), indicating that this stress-responsive complex plays a role in propagating the epigenetic memory of alcohol exposure through gestation. Importantly, transcriptional disruptions of the pathways regulating oxidative homeostasis correlate with the emergence of increased H3K9me2 across genic, repetitive, and non-transcribed regions of the genome. However, although associated with gene silencing, none of the candidate genes displaying increased H3K9me2 become transcriptionally repressed, nor do they exhibit increased markers of canonical heterochromatin. Similar to studies in C. elegans, disruptions in oxidative homeostasis induce the chromatin looping factor SATB2, but in mammals, this protein does not appear to drive increased H3K9me2 or altered patterns of gene expression. CONCLUSIONS: Our studies demonstrate that changes in H3K9me2 associate with alcohol-induced congenital defects, but that this epigenetic change does not correlate with transcriptional suppression. We speculate that the mobilization of SATB2 and increased enrichment of H3K9me2 may be components of a nuclear stress response that preserve chromatin integrity and interactions under prolonged oxidative stress. Further, we postulate that while this response may stabilize chromatin structure, it compromises the nuclear plasticity required for normal differentiation.


Assuntos
Etanol/toxicidade , Histonas , Fosforilação Oxidativa , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Histonas/metabolismo , Camundongos , Mitocôndrias/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , Transcriptoma
12.
Mol Metab ; 30: 161-172, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31767168

RESUMO

OBJECTIVES: Paternally inherited alterations in epigenetic programming are emerging as relevant factors in numerous disease states, including the growth and metabolic defects observed in fetal alcohol spectrum disorders. In rodents, chronic paternal alcohol use induces fetal growth restriction, as well as sex-specific alterations in insulin signaling and lipid homeostasis in the offspring. Based on previous studies, we hypothesized that the observed metabolic irregularities are the consequence of paternally inherited alterations liver x receptor (LXR) activity. METHODS: Male offspring of alcohol-exposed sires were challenged with a high-fat diet and the molecular pathways controlling glucose and lipid homeostasis assayed for LXR-induced alterations. RESULTS: Similar to findings in studies employing LXR agonists we found that the male offspring of alcohol-exposed sires display resistance to diet-induced obesity and improved glucose homeostasis when challenged with a high-fat diet. This improved metabolic adaptation is mediated by LXRα trans-repression of inflammatory cytokines, releasing IKKß inhibition of the insulin signaling pathway. Interestingly, paternally programmed increases in LXRα expression are liver-specific and do not manifest in the pancreas or visceral fat. CONCLUSIONS: These studies identify LXRα as a key mediator of the long-term metabolic alterations induced by preconception paternal alcohol use.


Assuntos
Etanol/efeitos adversos , Receptores X do Fígado/metabolismo , Obesidade/etiologia , Animais , Dieta Hiperlipídica/efeitos adversos , Epigênese Genética/genética , Feminino , Transtornos do Espectro Alcoólico Fetal/genética , Insulina/metabolismo , Fígado/metabolismo , Masculino , Camundongos , Obesidade/metabolismo , Exposição Paterna , Gravidez
15.
Food Chem Toxicol ; 45(7): 1263-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17336439

RESUMO

This study has measured the content of total and inorganic forms of arsenic in seaweed available on retail sale for consumption, to provide data for dietary exposure estimates and to support advice to consumers. A total of 31 samples covering five varieties of seaweed were collected from various retail outlets across London and the internet. All of the samples were purchased as dried product. For four of the five varieties, soaking was advised prior to consumption. The recommended method of preparation for each individual sample was followed, and total and inorganic arsenic were analysed both before and after preparation. The arsenic remaining in the water used for soaking was also measured. Arsenic was detected in all samples with total arsenic at concentrations ranging from 18 to 124 mg/kg. Inorganic arsenic, which can cause liver cancer, was only found in the nine samples of hijiki seaweed that were analysed, at concentrations in the range 67-96 mg/kg. Other types of seaweed were all found to contain less than 0.3mg/kg inorganic arsenic, which was the limit of detection for the method used. Since consumption of hijiki seaweed could significantly increase dietary exposure to inorganic arsenic, the UK Food Standards Agency (FSA) issued advice to consumers to avoid eating it.


Assuntos
Arsenicais/química , Exposição Ambiental/análise , Contaminação de Alimentos/análise , Alga Marinha/química , Poluentes Químicos da Água/química , Arsenicais/análise , Qualidade de Produtos para o Consumidor/normas , Exposição Ambiental/efeitos adversos , Monitoramento Ambiental/métodos , Medição de Risco , Poluentes Químicos da Água/análise
16.
Biol Bull ; 209(2): 154-63, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16260775

RESUMO

The musculature of the cubomedusa Tripedalia cystophora was investigated using immunohistochemical staining with an anti-actin antibody and histochemical staining with fluorescent phalloidin. The subumbrella is lined with a sheet of circular, striated muscle that is interrupted at the perradii, and by the nerve ring. The sheet is continuous with circular, striated muscle of the velarium, which turns radially on each face of the four velarial frenula. Perradial strips of smooth muscle run radially from just above the level of the rhopalia into the manubrium and lips. The strips give off perpendicular offshoots that run a short distance in parallel with the circular swim muscle. Musculature of the tentacles and pedalia is longitudinal and limited to the oral side of the pedalia. The pedalial muscle connects with bundles of smooth muscle that runs circularly from the tentacle base well into the subumbrella. The arrangement of striated muscle in the frenula suggests that these structures may function in directional nozzle formation of the velarium during turning. In addition, the perpendicular branching of the radial strips and the circular extensions of pedalial muscle may function in hinge formation to aid bending of the pedalia and tentacles into the subumbrella during feeding and protective responses.


Assuntos
Cubomedusas/anatomia & histologia , Músculos/anatomia & histologia , Animais , Imuno-Histoquímica , Microscopia de Fluorescência , Faloidina
17.
FEMS Microbiol Lett ; 226(1): 113-9, 2003 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-13129616

RESUMO

Atomic force microscopy analysis of polyhydroxyalkanoate (PHA) inclusions isolated from sonicated Ralstonia eutropha cells revealed that they exhibit two types of surface structure and shape; rough and ovoid, or smooth and spherical. Smooth inclusions possessed linear surface structures that were in parallel arrays with 7-nm spacing. Occasionally, cracks or fissures could be seen on the surface of the rough inclusions, which allowed a measurement of approximately 4 nm for the thickness of the boundary layer. When the rough inclusions were imaged at higher resolution, globular structures, 35 nm in diameter, having a central pore could be seen. These globular structures were connected by a network of 4-nm-wide linear structures. When the inclusions were treated with sodium lauryl sulfate, the boundary layer of the inclusion deteriorated in a manner that would be consistent with a lipid envelope. When the boundary layer was largely gone, 35-nm globular disks could be imaged laying on the surface of the filter beside the inclusions. These data have facilitated the development of a preliminary model for PHA inclusion structure that is more advanced than previous models.


Assuntos
Cupriavidus necator/metabolismo , Cupriavidus necator/ultraestrutura , Corpos de Inclusão/ultraestrutura , Microscopia de Força Atômica/métodos , Poliésteres/metabolismo , Dodecilsulfato de Sódio , Sonicação
18.
Eur J Paediatr Neurol ; 18(1): 30-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24011626

RESUMO

BACKGROUND: Aicardi-Goutières syndrome (AGS) is a genetically determined early-onset encephalopathy with variable phenotype, including neurologic manifestations such as dystonia, spasticity, epileptic seizures, progressive microcephaly, and severe developmental delay. The aim of our study was the characterization of epilepsy, one of the most frequent and severe AGS manifestations, in molecularly confirmed patients. METHODS: We reviewed the medical records, EEG, and CT/MRI findings in 16 patients aged 1-22 years that carried AGS1-5 mutations. RESULTS: Epilepsy manifested in 12 (75%) patients and took a refractory course in 9 (56%). 4 (25%) patients presented with seizures in the first four weeks and 11 (69%) altogether in the first year of life. Spasms were reported in 3 (19%) patients, focal seizures in 4 (25%), myoclonic in 5 (31%), symmetric or asymmetric tonic in 11 (69%), generalized tonic-clonic in 3 (19%) and status epilepticus in 4 (25%). EEG recordings initially showed a slow and disorganized background, followed by a regional intermittent theta/delta slow, while obvious multifocal or generalized epileptic discharges were only observed at follow-up. None of these EEG features were specific of AGS. There was no discernible correlation between the genotype and epilepsy onset, seizure types and epilepsy evolution. Epilepsy severity did not correspond to neuroimaging pathology. DISCUSSION: Epilepsy constitutes a cardinal feature of AGS, characterized by early onset, predominantly tonic semiology and a refractory course. The early discrimination of epileptic seizures from paroxysmal dystonia poses a challenge for neuropaediatricians, considering the initially inconspicuous or non-specific EEG findings. This study underlines the necessity of a more systematic serial evaluation of AGS patients using long-term video-EEG recordings.


Assuntos
Doenças Autoimunes do Sistema Nervoso/fisiopatologia , Epilepsia/fisiopatologia , Malformações do Sistema Nervoso/fisiopatologia , Adolescente , Adulto , Idade de Início , Doenças Autoimunes do Sistema Nervoso/complicações , Doenças Autoimunes do Sistema Nervoso/genética , Criança , Pré-Escolar , Epilepsia/etiologia , Epilepsia/genética , Seguimentos , Humanos , Lactente , Malformações do Sistema Nervoso/complicações , Malformações do Sistema Nervoso/genética , Fenótipo , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto Jovem
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