974 resultados para PRENATAL LPS
Resumo:
Congenital tracheal lesions are rare, but important, causes of morbidity in infants and children. Consequently, experience in their management is limited and dispersed. Given its small diameter, the juvenile trachea is obstructed easily by various natural causes, or following a surgical intervention. The diagnosis of a congenital, tracheal, obstructive anomaly is based on a high degree of suspicion in infants and children with respiratory distress accompanied by retraction. In this article, the authors discuss the various causes of these conditions, their diagnostic features, and the treatment possibilities.
Resumo:
The NACHT, LRR and PYD domains-containing protein 3 (NLRP3) inflammasome is one of the main sources of interleukin-1β (IL-1β) and is involved in several inflammatory-related pathologies. To date, its relationship with pain has not been studied in depth. The aim of our study was to elucidate the role of NLRP3 inflammasome and IL-1β production on neuropathic pain. Results showed that basal pain sensitivity is unaltered in NLRP3-/- mice as well as responses to formalin test. Spared nerve injury (SNI) surgery induced the development of mechanical allodynia and thermal hyperalgesia in a similar way in both genotypes and did not modify mRNA levels of the NLRP3 inflammasome components in the spinal cord. Intrathecal lipopolysaccharide (LPS) injection increases apoptosis-associated speck like protein (ASC), caspase-1 and IL-1β expression in both wildtype and NLRP3-/- mice. Those data suggest that NLRP3 is not involved in neuropathic pain and also that other sources of IL-1β are implicated in neuroinflammatory responses induced by LPS.
Resumo:
Emerging as an important correlate of neurological dysfunction in Multiple Sclerosis (MS), extended focal and diffuse gray matter abnormalities have been found and linked to clinical manifestations such as seizures, fatigue and cognitive dysfunction. To investigate possible underlying mechanisms we analyzed the molecular alterations in histopathological normal appearing cortical gray matter (NAGM) in MS. By performing a differential gene expression analysis of NAGM of control and MS cases we identified reduced transcription of astrocyte specific genes involved in the astrocyte-neuron lactate shuttle (ANLS) and the glutamate-glutamine cycle (GGC). Additional quantitative immunohistochemical analysis demonstrating a CX43 loss in MS NAGM confirmed a crucial involvement of astrocytes and emphasizes their importance in MS pathogenesis. Concurrently, a Toll-like/IL-1β signaling expression signature was detected in MS NAGM, indicating that immune-related signaling might be responsible for the downregulation of ANLS and GGC gene expression in MS NAGM. Indeed, challenging astrocytes with immune stimuli such as IL-1β and LPS reduced their ANLS and GGC gene expression in vitro. The detected upregulation of IL1B in MS NAGM suggests inflammasome priming. For this reason, astrocyte cultures were treated with ATP and ATP/LPS as for inflammasome activation. This treatment led to a reduction of ANLS and GGC gene expression in a comparable manner. To investigate potential sources for ANLS and GGC downregulation in MS NAGM, we first performed an adjuvant-driven stimulation of the peripheral immune system in C57Bl/6 mice in vivo. This led to similar gene expression changes in spinal cord demonstrating that peripheral immune signals might be one source for astrocytic gene expression changes in the brain. IL1B upregulation in MS NAGM itself points to a possible endogenous signaling process leading to ANLS and GGC downregulation. This is supported by our findings that, among others, MS NAGM astrocytes express inflammasome components and that astrocytes are capable to release Il-1β in-vitro. Altogether, our data suggests that immune signaling of immune- and/or central nervous system origin drives alterations in astrocytic ANLS and GGC gene regulation in the MS NAGM. Such a mechanism might underlie cortical brain dysfunctions frequently encountered in MS patients.
Resumo:
Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS), bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish) and Tenebrio molitor larvae (mealworm). The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core) is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT) containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the proPO system and as virulence factors for this bacterium.
Resumo:
Objetivo: Averiguar el consumo de tabaco y las modificaciones del hábito durante la gestación, y observar las recaídas después del parto. Personas y método: Estudio descriptivo transversal, realizado en el PASSIR «Casagemas», Badalona, desde febrero de 2006 a septiembre de 2007. Se incluyó a 115 gestantes que acudieron a la consulta de control prenatal en el tercer trimestre de gestación, y se excluyeron las que no fumaban al inicio de la gestación. Se recogieron variables sociodemográficas y las relacionadas con el hábito tabáquico a través de un cuestionario en la gestación y otro en el posparto. Resultados: Dejaron de fumar el 26% (30) de las gestantes, y las que continuaron fumando redujeron el consumo de una media de 19,2 (DE= 6,7) a 7,2 (DE= 6) cigarrillos/día. Se observaron diferencias en el abandono del tabaco en aquellas que fumaban un menor número de cigarrillos (p <0,001), en las que iniciaron el tabaquismo más tarde y en las de mayor edad (p= 0,013). Al año del parto, seguían fumando el 73% (70) de las mujeres, y habían recaído en el hábito el 39,2% (11) de las que lo habían abandonado en la gestación. Las mujeres que no fumaban lactaron a sus hijos un 76,9% (20), mientras que las que fumaban lo hicieron un 57,1% (40). La duración media de la lactancia fue inferior en las mujeres que fumaron en el posparto (2,81 meses [DE= 3,4]) en relación con las que no lo hicieron (4,96 meses [DE= 4,1]; p= 0,01). Conclusiones: La tasa de abandono del tabaco durante el embarazo es aún muy baja, y el índice de recaída del hábito tabáquico en el posparto, elevada.
Resumo:
Objetivo: Averiguar el consumo de tabaco y las modificaciones del hábito durante la gestación, y observar las recaídas después del parto. Personas y método: Estudio descriptivo transversal, realizado en el PASSIR «Casagemas», Badalona, desde febrero de 2006 a septiembre de 2007. Se incluyó a 115 gestantes que acudieron a la consulta de control prenatal en el tercer trimestre de gestación, y se excluyeron las que no fumaban al inicio de la gestación. Se recogieron variables sociodemográficas y las relacionadas con el hábito tabáquico a través de un cuestionario en la gestación y otro en el posparto. Resultados: Dejaron de fumar el 26% (30) de las gestantes, y las que continuaron fumando redujeron el consumo de una media de 19,2 (DE= 6,7) a 7,2 (DE= 6) cigarrillos/día. Se observaron diferencias en el abandono del tabaco en aquellas que fumaban un menor número de cigarrillos (p <0,001), en las que iniciaron el tabaquismo más tarde y en las de mayor edad (p= 0,013). Al año del parto, seguían fumando el 73% (70) de las mujeres, y habían recaído en el hábito el 39,2% (11) de las que lo habían abandonado en la gestación. Las mujeres que no fumaban lactaron a sus hijos un 76,9% (20), mientras que las que fumaban lo hicieron un 57,1% (40). La duración media de la lactancia fue inferior en las mujeres que fumaron en el posparto (2,81 meses [DE= 3,4]) en relación con las que no lo hicieron (4,96 meses [DE= 4,1]; p= 0,01). Conclusiones: La tasa de abandono del tabaco durante el embarazo es aún muy baja, y el índice de recaída del hábito tabáquico en el posparto, elevada.
Resumo:
Fetoscopic coagulation of placental anastomoses is the treatment of choice for severe twin-to-twin transfusion syndrome. In the present day, fetal laser therapy is also used to treat amniotic bands, chorioangiomas, sacrococcygeal teratomas, lower urinary tract obstructions and chest masses, all of which will be reviewed in this article. Amniotic band syndrome can cause limb amputation by impairing downstream blood flow. Large chorioangiomas (>4 cm), sacrococcygeal teratomas or fetal hyperechoic lung lesions can lead to fetal compromise and hydrops by vascular steal phenomenon or compression. Renal damage, bladder dysfunction and lastly death because of pulmonary hypolasia may be the result of megacystis caused by a posterior urethral valve. The prognosis of these pathologies can be dismal, and therapy options are limited, which has brought fetal laser therapy to the forefront. Management options discussed here are laser release of amniotic bands, laser coagulation of the placental or fetal tumor feeding vessels and laser therapy by fetal cystoscopy. This review, largely based on case reports, does not intend to provide a level of evidence supporting laser therapy over other treatment options. Centralized evaluation by specialists using strict selection criteria and long-term follow-up of these rare cases are now needed to prove the value of endoscopic or ultrasound-guided laser therapy.
Resumo:
Les bactéries du genre Pseudomonas ont la capacité étonnante de s'adapter à différents habitats et d'y survivre, ce qui leur a permis de conquérir un large éventail de niches écologiques et d'interagir avec différents organismes hôte. Les espèces du groupe Pseudomonas fluorescens peuvent être facilement isolées de la rhizosphère et sont communément connues comme des Pseudomonas bénéfiques pour les plantes. Elles sont capables d'induire la résistance systémique des plantes, d'induire leur croissance et de contrer des phytopathogènes du sol. Un sous-groupe de ces Pseudomonas a de plus développé la capacité d'infecter et de tuer certaines espèces d'insectes. Approfondir les connaissances sur l'interaction de ces bactéries avec les insectes pourraient conduire au développement de nouveaux biopesticides pour la protection des cultures. Le but de cette thèse est donc de mieux comprendre la base moléculaire, l'évolution et la régulation de la pathogénicité des Pseudomonas plante-bénéfiques envers les insectes. Plus spécifiquement, ce travail a été orienté sur l'étude de la production de la toxine insecticide appelée Fit et sur l'indentification d'autres facteurs de virulence participant à la toxicité de la bactérie envers les insectes. Dans la première partie de ce travail, la régulation de la production de la toxine Fit a été évaluée par microscopie à épifluorescence en utilisant des souches rapportrices de Pseudomonas protegens CHA0 qui expriment la toxine insecticide fusionnée à une protéine fluorescente rouge, au site natif du gène de la toxine. Celle-ci a été détectée uniquement dans l'hémolymphe des insectes et pas sur les racines des plantes, ni dans les milieux de laboratoire standards, indiquant une production dépendante de l'hôte. L'activation de la production de la toxine est contrôlée par trois protéines régulatrices dont l'histidine kinase FitF, essentielle pour un contrôle précis de l'expression et possédant un domaine "senseur" similaire à celui de la kinase DctB qui régule l'absorption de carbone chez les Protéobactéries. Il est donc probable que, durant l'évolution de FitF, un réarrangement de ce domaine "senseur" largement répandu ait contribué à une production hôte-spécifique de la toxine. Les résultats de cette étude suggèrent aussi que l'expression de la toxine Fit est plutôt réprimée en présence de composés dérivés des plantes qu'induite par la perception d'un signal d'insecte spécifique. Dans la deuxième partie de ce travail, des souches mutantes ciblant des facteurs de virulence importants identifiés dans des pathogènes connus ont été générées, dans le but d'identifier ceux avec une virulence envers les insectes atténuée. Les résultats ont suggéré que l'antigène O du lipopolysaccharide (LPS) et le système régulateur à deux composantes PhoP/PhoQ contribuent significativement à la virulence de P. protegens CHA0. La base génétique de la biosynthèse de l'antigène O dans les Pseudomonas plante-bénéfiques et avec une activité insecticide a été élucidée et a révélé des différences considérables entre les lignées suite à des pertes de gènes ou des acquisitions de gènes par transfert horizontal durant l'évolution de certaines souches. Les chaînes latérales du LPS ont été montrées comme vitales pour une infection des insectes réussie par la souche CHA0, après ingestion ou injection. Les Pseudomonas plante-bénéfiques, avec une activité insecticide sont naturellement résistants à la polymyxine B, un peptide antimicrobien modèle. La protection contre ce composé antimicrobien particulier dépend de la présence de l'antigène O et de la modification du lipide A, une partie du LPS, avec du 4-aminoarabinose. Comme les peptides antimicrobiens cationiques jouent un rôle important dans le système immunitaire des insectes, l'antigène O pourrait être important chez les Pseudomonas insecticides pour surmonter les mécanismes de défense de l'hôte. Le système PhoP/PhoQ, connu pour contrôler les modifications du lipide A chez plusieurs bactéries pathogènes, a été identifié chez Pseudomonas chlororaphis PCL1391 et P. protegens CHA0. Pour l'instant, il n'y a pas d'évidence que des modifications du lipide A contribuent à la pathogénicité de cette bactérie envers les insectes. Cependant, le senseur-kinase PhoQ est requis pour une virulence optimale de la souche CHA0, ce qui suggère qu'il régule aussi l'expression des facteurs de virulence de cette bactérie. Les découvertes de cette thèse démontrent que certains Pseudomonas associés aux plantes sont de véritables pathogènes d'insectes et donnent quelques indices sur l'évolution de ces microbes pour survivre dans l'insecte-hôte et éventuellement le tuer. Les résultats suggèrent également qu'une recherche plus approfondie est nécessaire pour comprendre comment ces bactéries sont capables de contourner ou surmonter la réponse immunitaire de l'hôte et de briser les barrières physiques pour envahir l'insecte lors d'une infection orale. Pour cela, les futures études ne devraient pas uniquement se concentrer sur le côté bactérien de l'interaction hôte-microbe, mais aussi étudier l'infection du point de vue de l'hôte. Les connaissances gagnées sur la pathogénicité envers les insectes des Pseudomonas plante-bénéfiques donnent un espoir pour une future application en agriculture, pour protéger les plantes, non seulement contre les maladies, mais aussi contre les insectes ravageurs. -- Pseudomonas bacteria have the astonishing ability to survive within and adapt to different habitats, which has allowed them to conquer a wide range of ecological niches and to interact with different host organisms. Species of the Pseudomonas fluorescens group can readily be isolated from plant roots and are commonly known as plant-beneficial pseudomonads. They are capable of promoting plant growth, inducing systemic resistance in the plant host and antagonizing soil-borne phytopathogens. A defined subgroup of these pseudomonads evolved in addition the ability to infect and kill certain insect species. Profound knowledge about the interaction of these particular bacteria with insects could lead to the development of novel biopesticides for crop protection. This thesis thus aimed at a better understanding of the molecular basis, evolution and regulation of insect pathogenicity in plant-beneficial pseudomonads. More specifically, it was outlined to investigate the production of an insecticidal toxin termed Fit and to identify additional factors contributing to the entomopathogenicity of the bacteria. In the first part of this work, the regulation of Fit toxin production was probed by epifluorescence microscopy using reporter strains of Pseudomonas protegens CHAO that express a fusion between the insecticidal toxin and a red fluorescent protein in place of the native toxin gene. The bacterium was found to express its insecticidal toxin only in insect hemolymph but not on plant roots or in common laboratory media. The host-dependent activation of Fit toxin production is controlled by three local regulatory proteins. The histidine kinase of this regulatory system, FitF, is essential for the tight control of toxin expression and shares a sensing domain with DctB, a sensor kinase regulating carbon uptake in Proteobacteria. It is therefore likely that shuffling of a ubiquitous sensor domain during the evolution of FitF contributed to host- specific production of the Fit toxin. Findings of this study additionally suggest that host-specific expression of the Fit toxin is mainly achieved by repression in the presence of plant-derived compounds rather than by induction upon perceiving an insect-specific signal molecule. In the second part of this thesis, mutant strains were generated that lack factors previously shown to be important for virulence in prominent pathogens. A screening for attenuation in insect virulence suggested that lipopolysaccharide (LPS) O-antigen and the PhoP-PhoQ two-component regulatory system significantly contribute to virulence of P. protegens CHAO. The genetic basis of O-antigen biosynthesis in plant-beneficial pseudomonads displaying insect pathogenicity was elucidated and revealed extensive differences between lineages due to reduction and horizontal acquisition of gene clusters during the evolution of several strains. Specific 0 side chains of LPS were found to be vital for strain CHAO to successfully infect insects by ingestion or upon injection. Insecticidal pseudomonads with plant-beneficial properties were observed to be naturally resistant to polymyxin B, a model antimicrobial peptide. Protection against this particular antimicrobial compound was dependent on the presence of O-antigen and modification of the lipid A portion of LPS with 4-aminoarabinose. Since cationic antimicrobial peptides play a major role in the immune system of insects, O-antigenic polysaccharides could be important for insecticidal pseudomonads to overcome host defense mechanisms. The PhoP-PhoQ system, which is well-known to control lipid A modifications in several pathogenic bacteria, was identified in Pseudomonas chlororaphis PCL1391 and P. protegens CHAO. No evidence was found so far that lipid A modifications contribute to insect pathogenicity in this bacterium. However, the sensor kinase PhoQ was required for full virulence of strain CHAO suggesting that it additionally regulates the expression of virulence factors in this bacterium. The findings of this thesis demonstrate that certain plant-associated pseudomonads are true insect pathogens and give some insights into how these microbes evolved to survive within and eventually kill the insect host. Results however also point out that more in-depth research is needed to know how exactly these fascinating bacteria manage to bypass or overcome host immune responses and to breach physical barriers to invade insects upon oral infection. To achieve this, future studies should not only focus on the bacterial side of the microbe-host interactions but also investigate the infection from a host-oriented view. The knowledge gained about the entomopathogenicity of plant-beneficial pseudomonads gives hope for their future application in agriculture to protect plants not only against plant diseases but also against insect pests.
Resumo:
INTRODUCTION: Late presentation to HIV care leads to increased morbidity and mortality. We explored risk factors and reasons for late HIV testing and presentation to care in the nationally representative Swiss HIV Cohort Study (SHCS). METHODS: Adult patients enrolled in the SHCS between July 2009 and June 2012 were included. An initial CD4 count <350 cells/µl or an AIDS-defining illness defined late presentation. Demographic and behavioural characteristics of late presenters (LPs) were compared with those of non-late presenters (NLPs). Information on self-reported, individual barriers to HIV testing and care were obtained during face-to-face interviews. RESULTS: Of 1366 patients included, 680 (49.8%) were LPs. Seventy-two percent of eligible patients took part in the survey. LPs were more likely to be female (p<0.001) or from sub-Saharan Africa (p<0.001) and less likely to be highly educated (p=0.002) or men who have sex with men (p<0.001). LPs were more likely to have their first HIV test following a doctor's suggestion (p=0.01), and NLPs in the context of a regular check-up (p=0.02) or after a specific risk situation (p<0.001). The main reasons for late HIV testing were "did not feel at risk" (72%), "did not feel ill" (65%) and "did not know the symptoms of HIV" (51%). Seventy-one percent of the participants were symptomatic during the year preceding HIV diagnosis and the majority consulted a physician for these symptoms. CONCLUSIONS: In Switzerland, late presentation to care is driven by late HIV testing due to low risk perception and lack of awareness about HIV. Tailored HIV testing strategies and enhanced provider-initiated testing are urgently needed.
Resumo:
OBJECTIVES: This study's aim was to describe the emotional status of parents to be before and after the first-trimester combined prenatal screening test. METHODS: One hundred three couples participated, of which 52 had undergone an in vitro fertilization/intracytoplasmic sperm injection treatment [assisted reproductive technology (ART)] and 51 had conceived spontaneously. Participants completed the state scale of the State-trait Anxiety Inventory, the Edinburgh Depression Scale, and the Maternal and Paternal Antenatal Attachment Questionnaire before the first-trimester combined prenatal screening test at around 12 weeks of gestational age (T1) and just after receiving the results at approximately 14 weeks of gestational age (T2). RESULTS: We observed a significant decrease in anxiety and depression symptoms and a significant increase in attachment from T1 to T2. Results showed no differences between groups at either time point, which suggests that ART parents are more similar to than different from parents conceiving spontaneously. Furthermore, given the importance of anxiety during pregnancy, a subsample of women with clinical anxiety was identified. They had significantly higher rates of clinical depression and lower attachment. CONCLUSIONS: These results indicate that, regardless of whether conception was through ART or spontaneous, clinical anxiety in women over the prenatal testing period is associated with more vulnerability during pregnancy (i.e. clinical depression and less attachment to fetus). © 2015 John Wiley & Sons, Ltd.
Resumo:
Imaging plays a key role in the detection of a diaphragmatic pathology in utero. US is the screening method, but MRI is increasingly performed. Congenital diaphragmatic hernia is by far the most often diagnosed diaphragmatic pathology, but unilateral or bilateral eventration or paralysis can also be identified. Extralobar pulmonary sequestration can be located in the diaphragm and, exceptionally, diaphragmatic tumors or secondary infiltration of the diaphragm from tumors originating from an adjacent organ have been observed in utero. Congenital abnormalities of the diaphragm impair normal lung development. Prenatal imaging provides a detailed anatomical evaluation of the fetus and allows volumetric lung measurements. The comparison of these data with those from normal fetuses at the same gestational age provides information about the severity of pulmonary hypoplasia and improves predictions about the fetus's outcome. This information can help doctors and families to make decisions about management during pregnancy and after birth. We describe a wide spectrum of congenital pathologies of the diaphragm and analyze their embryological basis. Moreover, we describe their prenatal imaging findings with emphasis on MR studies, discuss their differential diagnosis and evaluate the limits of imaging methods in predicting postnatal outcome.
Resumo:
BACKGROUND: Pregnant women with asthma need to take medication during pregnancy. OBJECTIVE: We sought to identify whether there is an increased risk of specific congenital anomalies after exposure to antiasthma medication in the first trimester of pregnancy. METHODS: We performed a population-based case-malformed control study testing signals identified in a literature review. Odds ratios (ORs) of exposure to the main groups of asthma medication were calculated for each of the 10 signal anomalies compared with registrations with nonchromosomal, nonsignal anomalies as control registrations. In addition, exploratory analyses were done for each nonsignal anomaly. The data set included 76,249 registrations of congenital anomalies from 13 EUROmediCAT registries. RESULTS: Cleft palate (OR, 1.63; 95% CI, 1.05-2.52) and gastroschisis (OR, 1.89; 95% CI, 1.12-3.20) had significantly increased odds of exposure to first-trimester use of inhaled β2-agonists compared with nonchromosomal control registrations. Odds of exposure to salbutamol were similar. Nonsignificant ORs of exposure to inhaled β2-agonists were found for spina bifida, cleft lip, anal atresia, severe congenital heart defects in general, or tetralogy of Fallot. None of the 4 literature signals of exposure to inhaled steroids were confirmed (cleft palate, cleft lip, anal atresia, and hypospadias). Exploratory analyses found an association between renal dysplasia and exposure to the combination of long-acting β2-agonists and inhaled corticosteroids (OR, 3.95; 95% CI, 1.99-7.85). CONCLUSIONS: The study confirmed increased odds of first-trimester exposure to inhaled β2-agonists for cleft palate and gastroschisis and found a potential new signal for renal dysplasia associated with combined long-acting β2-agonists and inhaled corticosteroids. Use of inhaled corticosteroids during the first trimester of pregnancy seems to be safe in relation to the risk for a range of specific major congenital anomalies.
Resumo:
Osteogenesis imperfecta (OI) is a rare genetic disease. Today we are able to propose an adapted and efficient management to the patients with this rare disorder (and their families) thanks to a strong collaboration of clinicians and researchers. Recent knowledge regarding the genetics of OI permits an accurate diagnosis of the specific type of OI and its own molecular mechanism, a genetic counseling for family planning and prenatal diagnosis, and in addition more targeted therapeutic options. A specific support with re-education for patients with OI is necessary and efficient. To optimize patient care, a multidisciplinary consultation is proposed at the CHUV, moreover a web site is available for patients, families and therapists: www.infomaladiesrares.ch
Resumo:
Neurodevelopmental disruptions caused by obstetric complications play a role in the etiology of several phenotypes associated with neuropsychiatric diseases and cognitive dysfunctions. Importantly, it has been noticed that epigenetic processes occurring early in life may mediate these associations. Here, DNA methylation signatures at IGF2 (insulin-like growth factor 2) and IGF2BP1-3 (IGF2-binding proteins 1-3) were examined in a sample consisting of 34 adult monozygotic (MZ) twins informative for obstetric complications and cognitive performance. Multivariate linear regression analysis of twin data was implemented to test for associations between methylation levels and both birth weight (BW) and adult working memory (WM) performance. Familial and unique environmental factors underlying these potential relationships were evaluated. A link was detected between DNA methylation levels of two CpG sites in the IGF2BP1 gene and both BW and adult WM performance. The BW-IGF2BP1 methylation association seemed due to non-shared environmental factors influencing BW, whereas the WM-IGF2BP1 methylation relationship seemed mediated by both genes and environment. Our data is in agreement with previous evidence indicating that DNA methylation status may be related to prenatal stress and later neurocognitive phenotypes. While former reports independently detected associations between DNA methylation and either BW or WM, current results suggest that these relationships are not confounded by each other.
Resumo:
Primary rodent astroglial-enriched cultures are the most popular model to study astroglial biology in vitro. From the original methods described in the 1970's a great number of minor modifications have been incorporated into these protocols by different laboratories. These protocols result in cultures in which the astrocyte is the predominant cell type, but astrocytes are never 100% of cells in these preparations. The aim of this review is to bring attention to the presence of microglia in astroglial cultures because, in my opinion, the proportion of and the role that microglial cells play in astroglial cultures are often underestimated. The main problem with ignoring microglia in these cultures is that relatively minor amounts of microglia can be responsible for effects observed on cultures in which the astrocyte is the most abundant cell type. If the relative contributions of astrocytes and microglia are not properly assessed an observed effect can be erroneously attributed to the astrocytes. In order to illustrate this point the case of NO production in activated astroglial-enriched cultures is examined. Lipopolysaccharide (LPS) induces nitric oxide (NO) production in astroglial-enriched cultures and this effect is very often attributed to astrocytes. However, a careful review of the published data suggests that LPS-induced NO production in rodent astroglial-enriched cultures is likely to be mainly microglial in origin. This review considers cell culture protocol factors that can affect the proportion of microglial cells in astroglial cultures, strategies to minimize the proportion of microglia in these cultures, and specific markers that allow the determination of such microglial proportions.