1,125 research outputs found
Autism spectrum disorder: a neuro-immunometabolic hypothesis of the developmental origins
Fetal neuroinflammation and prenatal stress (PS) may contribute to lifelong
neurological disabilities. Astrocytes and microglia play a pivotal role, but
the mechanisms are poorly understood. Here, we test the hypothesis that via
gene-environment interactions, fetal neuroinflammation and PS may reprogram
glial immunometabolic phenotypes which impact neurodevelopment and
neurobehavior. This glial-neuronal interplay increases the risk for clinical
manifestation of autism spectrum disorder (ASD) in at-risk children. Drawing on
genomic data from the recently published series of ovine and rodent glial
transcriptome analyses with fetuses exposed to neuroinflammation or PS, we
conducted a secondary analysis against the Simons Foundation Autism Research
Initiative (SFARI) Gene database. We confirmed 21 gene hits. Using unsupervised
statistical network analysis, we then identified six clusters of probable
protein-protein interactions mapping onto the immunometabolic and stress
response networks and epigenetic memory. These findings support our hypothesis.
We discuss the implications for ASD etiology, early detection, and novel
therapeutic approaches.Comment: Supplemental Table and Data:
https://github.com/martinfrasch/ASD_origins_hypothesis. arXiv admin note:
text overlap with arXiv:1812.06617 | This is a different study with related
research context (relevance to ASD
The role of the vagus nerve during fetal development and its relationship with the environment
The autonomic nervous system (ANS) regulatory capacity begins before birth as
the sympathetic and parasympathetic activity contributes significantly to the
fetus' development. Several studies have shown how vagus nerve is involved in
many vital processes during fetal, perinatal and postnatal life: from the
regulation of inflammation through the anti-inflammatory cholinergic pathway,
which may affect the functioning of each organ, to the production of hormones
involved in bioenergetic metabolism. In addition, the vagus nerve has been
recognized as the primary afferent pathway capable of transmitting information
to the brain from every organ of the body. Therefore, this hypothesis paper
aims to review the development of ANS during fetal and perinatal life, focusing
particularly on the vagus nerve, to identify possible "critical windows" that
could impact its maturation. These "critical windows" could help clinicians
know when to monitor fetuses to effectively assess the developmental status of
both ANS and specifically the vagus nerve. In addition, this paper will focus
on which factors (i.e. fetal characteristics and behaviors, maternal lifestyle
and pathologies, placental health and dysfunction, labor, incubator conditions,
and drug exposure) may have an impact on the development of the vagus during
the above-mentioned "critical window" and how. This analysis could help
clinicians and stakeholders define precise guidelines for improving the
management of fetuses and newborns, particularly to reduce the potential
adverse environmental impacts on ANS development that may lead to persistent
long-term consequences. Since the development of ANS and the vagus influence
have been shown to be reflected in cardiac variability, this paper will rely in
particular on studies using fetal heart rate variability (fHRV) to monitor the
continued growth and health of both animal and human fetuses.Comment: Word count: 16,009 Tables: 1 Figures:
Early Biomarkers and Intervention Programs for the Infant Exposed to Prenatal Stress
Functional development of affective and reward circuits, cognition and
response inhibition later in life exhibits vulnerability periods during
gestation and early childhood. Extensive evidence supports the model that
exposure to stressors in the gestational period and early postnatal life
increases an individual's susceptibility to future impairments of functional
development. Recent versions of this model integrate epigenetic mechanisms of
the developmental response. Their understanding will guide the future treatment
of the associated neuropsychiatric disorders. A combination of non-invasively
obtainable physiological signals and epigenetic biomarkers related to the
principal systems of the stress response, the Hypothalamic-Pituitary axis (HPA)
and the Autonomic Nervous System (ANS), are emerging as the key predictors of
neurodevelopmental outcomes. Such electrophysiological and epigenetic
biomarkers can prove to timely identify children benefiting most from early
intervention programs. Such programs should ameliorate future disorders in
otherwise apparently healthy children. The recently developed Early
Family-Centered Intervention Programs aim to influence the care and stimuli
provided daily by the family and improving parent/child attachment, a key
element for healthy socio-emotional adult life. Although frequently
underestimated, such biomarker-guided early intervention strategy represents a
crucial first step in the prevention of future neuropsychiatric problems and in
reducing their personal and societal impact.Comment: 18 pages-Revie
Detection of Maternal and Fetal Stress from the Electrocardiogram with Self-Supervised Representation Learning
In the pregnant mother and her fetus, chronic prenatal stress results in
entrainment of the fetal heartbeat by the maternal heartbeat, quantified by the
fetal stress index (FSI). Deep learning (DL) is capable of pattern detection in
complex medical data with high accuracy in noisy real-life environments, but
little is known about DL's utility in non-invasive biometric monitoring during
pregnancy. A recently established self-supervised learning (SSL) approach to DL
provides emotional recognition from electrocardiogram (ECG). We hypothesized
that SSL will identify chronically stressed mother-fetus dyads from the raw
maternal abdominal electrocardiograms (aECG), containing fetal and maternal
ECG. Chronically stressed mothers and controls matched at enrolment at 32 weeks
of gestation were studied. We validated the chronic stress exposure by
psychological inventory, maternal hair cortisol and FSI. We tested two variants
of SSL architecture, one trained on the generic ECG features for emotional
recognition obtained from public datasets and another transfer-learned on a
subset of our data. Our DL models accurately detect the chronic stress exposure
group (AUROC=0.982+/-0.002), the individual psychological stress score
(R2=0.943+/-0.009) and FSI at 34 weeks of gestation (R2=0.946+/-0.013), as well
as the maternal hair cortisol at birth reflecting chronic stress exposure
(0.931+/-0.006). The best performance was achieved with the DL model trained on
the public dataset and using maternal ECG alone. The present DL approach
provides a novel source of physiological insights into complex multi-modal
relationships between different regulatory systems exposed to chronic stress.
The final DL model can be deployed in low-cost regular ECG biosensors as a
simple, ubiquitous early stress detection and monitoring tool during pregnancy.
This discovery should enable early behavioral interventions.Comment: ClinicalTrials.gov registration number: NCT03389178. Code repo:
https://code.engineering.queensu.ca/17ps21/ssl-ecg-v
Palmitoylethanolamide exerts neuroprotective effects in mixed neuroglial cultures and organotypic hippocampal slices via peroxisome proliferator-activated receptor-α
<p>Abstract</p> <p>Background</p> <p>In addition to cytotoxic mechanisms directly impacting neurons, β-amyloid (Aβ)-induced glial activation also promotes release of proinflammatory molecules that may self-perpetuate reactive gliosis and damage neighbouring neurons, thus amplifying neuropathological lesions occurring in Alzheimer's disease (AD). Palmitoylethanolamide (PEA) has been studied extensively for its anti-inflammatory, analgesic, antiepileptic and neuroprotective effects. PEA is a lipid messenger isolated from mammalian and vegetable tissues that mimics several endocannabinoid-driven actions, even though it does not bind to cannabinoid receptors. Some of its pharmacological properties are considered to be dependent on the expression of peroxisome proliferator-activated receptors-α (PPARα).</p> <p>Findings</p> <p>In the present study, we evaluated the effect of PEA on astrocyte activation and neuronal loss in models of Aβ neurotoxicity. To this purpose, primary rat mixed neuroglial co-cultures and organotypic hippocampal slices were challenged with Aβ<sub>1-42 </sub>and treated with PEA in the presence or absence of MK886 or GW9662, which are selective PPARα and PPARγ antagonists, respectively. The results indicate that PEA is able to blunt Aβ-induced astrocyte activation and, subsequently, to improve neuronal survival through selective PPARα activation. The data from organotypic cultures confirm that PEA anti-inflammatory properties implicate PPARα mediation and reveal that the reduction of reactive gliosis subsequently induces a marked rebound neuroprotective effect on neurons.</p> <p>Conclusions</p> <p>In line with our previous observations, the results of this study show that PEA treatment results in decreased numbers of infiltrating astrocytes during Aβ challenge, resulting in significant neuroprotection. PEA could thus represent a promising pharmacological tool because it is able to reduce Aβ-evoked neuroinflammation and attenuate its neurodegenerative consequences.</p
Human Papillomaviruses and genital co-infections in gynaecological outpatients
<p>Abstract</p> <p>Background</p> <p>High grade HPV infections and persistence are the strongest risk factors for cervical cancer. Nevertheless other genital microorganisms may be involved in the progression of HPV associated lesions.</p> <p>Methods</p> <p>Cervical samples were collected to search for human Papillomavirus (HPV), bacteria and yeast infections in gynaecologic outpatients. HPV typing was carried out by PCR and sequencing on cervical brush specimens. <it>Chlamydia trachomatis </it>was identified by strand displacement amplification (SDA) and the other microorganisms were detected by conventional methods.</p> <p>Results</p> <p>In this cross-sectional study on 857 enrolled outpatients, statistical analyses revealed a significant association of HPV with <it>C. trachomatis </it>and <it>Ureaplasma urealyticum (</it>at high density) detection, whereas no correlation was found between HPV infection and bacterial vaginosis, <it>Streptococcus agalactiae</it>, yeasts, <it>Trichomonas vaginalis </it>and <it>U. urealyticum</it>. <it>Mycoplasma hominis </it>was isolated only in a few cases both in HPV positive and negative women and no patient was infected with <it>Neisseria gonorrhoeae</it>.</p> <p>Conclusion</p> <p>Although bacterial vaginosis was not significantly associated with HPV, it was more common among the HPV positive women. A significant association between HPV and <it>C. trachomatis </it>was found and interestingly also with <it>U. urealyticum </it>but only at a high colonization rate. These data suggest that it may be important to screen for the simultaneous presence of different microorganisms which may have synergistic pathological effects.</p
α7 Nicotinic Acetylcholine Receptor Signaling Modulates Ovine Fetal Brain Astrocytes Transcriptome in Response to Endotoxin
Neuroinflammation in utero may result in lifelong neurological disabilities. Astrocytes play a pivotal role in this process, but the mechanisms are poorly understood. No early postnatal treatment strategies exist to enhance neuroprotective potential of astrocytes. We hypothesized that agonism on α7 nicotinic acetylcholine receptor (α7nAChR) in fetal astrocytes will augment their neuroprotective transcriptome profile, while the inhibition of α7nAChR will achieve the opposite. Using an in vivo–in vitro model of developmental programming of neuroinflammation induced by lipopolysaccharide (LPS), we validated this hypothesis in primary fetal sheep astrocytes cultures re-exposed to LPS in the presence of a selective α7nAChR agonist or antagonist. Our RNAseq findings show that a pro-inflammatory astrocyte transcriptome phenotype acquired in vitro by LPS stimulation is reversed with α7nAChR agonistic stimulation. Conversely, α7nAChR inhibition potentiates the pro-inflammatory astrocytic transcriptome phenotype. Furthermore, we conducted a secondary transcriptome analysis against the identical α7nAChR experiments in fetal sheep primary microglia cultures. Similar to findings in fetal microglia, in fetal astrocytes we observed a memory effect of in vivo exposure to inflammation, expressed in a perturbation of the iron homeostasis signaling pathway (hemoxygenase 1, HMOX1), which persisted under pre-treatment with α7nAChR antagonist but was reversed with α7nAChR agonist. For both glia cell types, common pathways activated due to LPS included neuroinflammation signaling and NF-κB signaling in some, but not all comparisons. However, overall, the overlap on the level of signaling pathways was rather minimal. Astrocytes, not microglia—the primary immune cells of the brain, were characterized by unique inhibition patterns of STAT3 pathway due to agonistic stimulation of α7nAChR prior to LPS exposure. Lastly, we discuss the implications of our findings for fetal and postnatal brain development
The Polarized Cosmic Hand: IXPE Observations of PSR B1509-58/MSH 15-52
We describe IXPE polarization observations of the Pulsar Wind Nebula (PWN)
MSH15-52, the `Cosmic Hand'. We find X-ray polarization across the PWN, with B
field vectors generally aligned with filamentary X-ray structures. High
significance polarization is seen in arcs surrounding the pulsar and toward the
end of the `jet', with polarization degree PD>70%, thus approaching the maximum
allowed synchrotron value. In contrast, the base of the jet has lower
polarization, indicating a complex magnetic field at significant angle to the
jet axis. We also detect significant polarization from PSR B1509-58 itself.
Although only the central pulse-phase bin of the pulse has high individual
significance, flanking bins provide lower significance detections and, in
conjunction with the X-ray image and radio polarization, can be used to
constrain rotating vector model solutions for the pulsar geometry.Comment: To appear in the Astrophysical Journa
The rapid spread of SARS-COV-2 Omicron variant in Italy reflected early through wastewater surveillance
The SARS-CoV-2 Omicron variant emerged in South Africa in November 2021, and has later been identified worldwide, raising serious concerns. A real-time RT-PCR assay was designed for the rapid screening of the Omicron variant, targeting characteristic mutations of the spike gene. The assay was used to test 737 sewage samples collected throughout Italy (19/21 Regions) between 11 November and 25 December 2021, with the aim of assessing the spread of the Omicron variant in the country. Positive samples were also tested with a real-time RT-PCR developed by the European Commission, Joint Research Centre (JRC), and through nested RT-PCR followed by Sanger sequencing. Overall, 115 samples tested positive for Omicron SARS-CoV-2 variant. The first occurrence was detected on 7 December, in Veneto, North Italy. Later on, the variant spread extremely fast in three weeks, with prevalence of positive wastewater samples rising from 1.0% (1/104 samples) in the week 5-11 December, to 17.5% (25/143 samples) in the week 12-18, to 65.9% (89/135 samples) in the week 19-25, in line with the increase in cases of infection with the Omicron variant observed during December in Italy. Similarly, the number of Regions/Autonomous Provinces in which the variant was detected increased from one in the first week, to 11 in the second, and to 17 in the last one. The presence of the Omicron variant was confirmed by the JRC real-time RT-PCR in 79.1% (91/115) of the positive samples, and by Sanger sequencing in 66% (64/97) of PCR amplicons. In conclusion, we designed an RT-qPCR assay capable to detect the Omicron variant, which can be successfully used for the purpose of wastewater-based epidemiology. We also described the history of the introduction and diffusion of the Omicron variant in the Italian population and territory, confirming the effectiveness of sewage monitoring as a powerful surveillance tool
EPIdemiology of Surgery-Associated Acute Kidney Injury (EPIS-AKI) : Study protocol for a multicentre, observational trial
More than 300 million surgical procedures are performed each year. Acute kidney injury (AKI) is a common complication after major surgery and is associated with adverse short-term and long-term outcomes. However, there is a large variation in the incidence of reported AKI rates. The establishment of an accurate epidemiology of surgery-associated AKI is important for healthcare policy, quality initiatives, clinical trials, as well as for improving guidelines. The objective of the Epidemiology of Surgery-associated Acute Kidney Injury (EPIS-AKI) trial is to prospectively evaluate the epidemiology of AKI after major surgery using the latest Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI. EPIS-AKI is an international prospective, observational, multicentre cohort study including 10 000 patients undergoing major surgery who are subsequently admitted to the ICU or a similar high dependency unit. The primary endpoint is the incidence of AKI within 72 hours after surgery according to the KDIGO criteria. Secondary endpoints include use of renal replacement therapy (RRT), mortality during ICU and hospital stay, length of ICU and hospital stay and major adverse kidney events (combined endpoint consisting of persistent renal dysfunction, RRT and mortality) at day 90. Further, we will evaluate preoperative and intraoperative risk factors affecting the incidence of postoperative AKI. In an add-on analysis, we will assess urinary biomarkers for early detection of AKI. EPIS-AKI has been approved by the leading Ethics Committee of the Medical Council North Rhine-Westphalia, of the Westphalian Wilhelms-University Münster and the corresponding Ethics Committee at each participating site. Results will be disseminated widely and published in peer-reviewed journals, presented at conferences and used to design further AKI-related trials. Trial registration number NCT04165369
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