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1.
Brain ; 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39054600

RESUMEN

Brain malformations represent a heterogeneous group of abnormalities of neural morphogenesis, often associated with aberrations of neuronal connectivity and brain volume. Prenatal detection of brain malformations requires a clear understanding of embryology and developmental morphology through the various stages of gestation. This expert panel review is written with the central aim of providing an easy-to-understand roadmap to improve prenatal detection and characterization of structural malformations based on the current understanding of normal and aberrant brain development. The utility of each available neuroimaging modality including prenatal multiplanar neurosonography, anatomical magnetic resonance imaging (MRI), and advanced MRI techniques, as well as further insights from post-mortem imaging have been highlighted for every developmental stage.

2.
Acta Obstet Gynecol Scand ; 103(5): 897-906, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38339766

RESUMEN

INTRODUCTION: This study aimed to assess the visibility of the indusium griseum (IG) in magnetic resonance (MR) scans of the human fetal brain and to evaluate its reliability as an imaging biomarker of the normality of brain midline development. MATERIAL AND METHODS: The retrospective observational study encompassed T2-w 3T MR images from 90 post-mortem fetal brains and immunohistochemical sections from 41 fetal brains (16-40 gestational weeks) without cerebral pathology. Three raters independently inspected and evaluated the visibility of IG in post-mortem and in vivo MR scans. Weighted kappa statistics and regression analysis were used to determine inter- and intra-rater agreement and the type and strength of the association of IG visibility with gestational age. RESULTS: The visibility of the IG was the highest between the 25 and 30 gestational week period, with a very good inter-rater variability (kappa 0.623-0.709) and excellent intra-rater variability (kappa 0.81-0.93). The immunochemical analysis of the histoarchitecture of IG discloses the expression of highly hydrated extracellular molecules in IG as the substrate of higher signal intensity and best visibility of IG during the mid-fetal period. CONCLUSIONS: The knowledge of developmental brain histology and fetal age allows us to predict the IG-visibility in magnetic resonance imaging (MRI) and use it as a biomarker to evaluate the morphogenesis of the brain midline. As a biomarker, IG is significant for post-mortem pathological examination by MRI. Therefore, in the clinical in vivo imaging examination, IG should be anticipated when an assessment of the brain midline structures is needed in mid-gestation, including corpus callosum thickness measurements.


Asunto(s)
Cuerpo Calloso , Imagen por Resonancia Magnética , Femenino , Humanos , Biomarcadores , Lóbulo Límbico , Imagen por Resonancia Magnética/métodos , Espectroscopía de Resonancia Magnética , Reproducibilidad de los Resultados , Embarazo
3.
J Appl Toxicol ; 2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39129338

RESUMEN

Owning to the increasing body of evidence about the ubiquitous exposure to endocrine disruptors (EDCs), particularly bisphenol A (BPA), and associated health effects, BPA has been gradually substituted with insufficiently tested structural analogs. The unmanaged excessive use of antimicrobial agents such as triclosan (TCS) during the COVID-19 outbreak has also raised concerns about its possible interferences with hormonal functions. The similarity of BPA and estradiol, as well as TCS and non-steroidal estrogens, imply that endocrine-disrupting properties of their analogs could be predicted based on the chemical structure. Hence, this study aimed to evaluate the endocrine-disrupting potential of BPA substitutes as well as TCS derivatives and degradation/biotransformation metabolites, in comparison to BPA and TCS based on their molecular properties, computational predictions of pharmacokinetics and binding affinities to nuclear receptors. Based on the obtained results several under-researched BPA analogs exhibited higher binding affinities for nuclear receptors than BPA. Notable analogs included compounds detected in receipts (DD-70, BTUM-70, TGSA, and BisOPP-A), along with a flame retardant, BDP. The possible health hazards linked to exposure to TCS and its mono-hydroxylated metabolites were also found. Further research is needed in order to elucidate the health impacts of these compounds and promote better regulation practices.

4.
Eur Radiol ; 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38019312

RESUMEN

OBJECTIVES: To investigate the advantage of T1-weighted fast fluid-attenuated inversion-recovery MRI sequence without (T1-FFLAIR) and with compressed sensing technology (T1-FFLAIR-CS), which shows improved T1-weighted contrast, over standard used T1-weighted fast field echo (T1-FFE) sequence for the assessment of fetal myelination. MATERIALS AND METHODS: This retrospective single-center study included 115 consecutive fetal brain MRI examinations (63 axial and 76 coronal, mean gestational age (GA) 28.56 ± 5.23 weeks, range 19-39 weeks). Two raters, blinded to GA, qualitatively assessed a fetal myelin total score (MTS) on each T1-weighted sequence at five brain regions (medulla oblongata, pons, mesencephalon, thalamus, central region). One rater performed region-of-interest quantitative analysis (n = 61) at the same five brain regions. Pearson correlation analysis was applied for correlation of MTS and of the signal intensity ratios (relative to muscle) with GA on each T1-weighted sequence. Fetal MRI-based results were compared with myelination patterns of postmortem fetal human brains (n = 46; GA 18 to 42), processed by histological and immunohistochemical analysis. RESULTS: MTS positively correlated with GA on all three sequences (all r between 0.802 and 0.908). The signal intensity ratios measured at the five brain regions correlated best with GA on T1-FFLAIR (r between 0.583 and 0.785). T1-FFLAIR demonstrated significantly better correlations with GA than T1-FFE for both qualitative and quantitative analysis (all p < 0.05). Furthermore, T1-FFLAIR enabled the best visualization of myelinated brain structures when compared to histology. CONCLUSION: T1-FFLAIR outperforms the standard T1-FFE sequence in the visualization of fetal brain myelination, as demonstrated by qualitative and quantitative methods. CLINICAL RELEVANCE STATEMENT: T1-weighted fast fluid-attenuated inversion-recovery sequence (T1-FFLAIR) provided best visualization and quantification of myelination in utero that, in addition to the relatively short acquisition time, makes feasible its routine application in fetal MRI for the assessment of brain myelination. KEY POINTS: • So far, the assessment of fetal myelination in utero was limited due to the insufficient contrast. • T1-weighted fast fluid-attenuated inversion-recovery sequence allows a qualitative and quantitative assessment of fetal brain myelination. • T1-weighted fast fluid-attenuated inversion-recovery sequence outperforms the standard used T1-weighted sequence for visualization and quantification of myelination in utero.

5.
Am J Hum Genet ; 105(6): 1126-1147, 2019 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-31735293

RESUMEN

The redox state of the neural progenitors regulates physiological processes such as neuronal differentiation and dendritic and axonal growth. The relevance of endoplasmic reticulum (ER)-associated oxidoreductases in these processes is largely unexplored. We describe a severe neurological disorder caused by bi-allelic loss-of-function variants in thioredoxin (TRX)-related transmembrane-2 (TMX2); these variants were detected by exome sequencing in 14 affected individuals from ten unrelated families presenting with congenital microcephaly, cortical polymicrogyria, and other migration disorders. TMX2 encodes one of the five TMX proteins of the protein disulfide isomerase family, hitherto not linked to human developmental brain disease. Our mechanistic studies on protein function show that TMX2 localizes to the ER mitochondria-associated membranes (MAMs), is involved in posttranslational modification and protein folding, and undergoes physical interaction with the MAM-associated and ER folding chaperone calnexin and ER calcium pump SERCA2. These interactions are functionally relevant because TMX2-deficient fibroblasts show decreased mitochondrial respiratory reserve capacity and compensatory increased glycolytic activity. Intriguingly, under basal conditions TMX2 occurs in both reduced and oxidized monomeric form, while it forms a stable dimer under treatment with hydrogen peroxide, recently recognized as a signaling molecule in neural morphogenesis and axonal pathfinding. Exogenous expression of the pathogenic TMX2 variants or of variants with an in vitro mutagenized TRX domain induces a constitutive TMX2 polymerization, mimicking an increased oxidative state. Altogether these data uncover TMX2 as a sensor in the MAM-regulated redox signaling pathway and identify it as a key adaptive regulator of neuronal proliferation, migration, and organization in the developing brain.


Asunto(s)
Encefalopatías/patología , Encéfalo/anomalías , Discapacidades del Desarrollo/patología , Proteínas de la Membrana/metabolismo , Mitocondrias/metabolismo , Tiorredoxinas/metabolismo , Adolescente , Adulto , Encefalopatías/genética , Encefalopatías/metabolismo , Niño , Preescolar , Estudios de Cohortes , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/metabolismo , Femenino , Fibroblastos/metabolismo , Fibroblastos/patología , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Proteínas de la Membrana/genética , Mitocondrias/patología , Oxidación-Reducción , Pronóstico , Piel/metabolismo , Piel/patología , Tiorredoxinas/genética , Transcriptoma
6.
Cereb Cortex ; 31(7): 3536-3550, 2021 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-33704445

RESUMEN

The purpose of the study was to investigate the interrelation of the signal intensities and thicknesses of the transient developmental zones in the cingulate and neocortical telencephalic wall, using T2-weighted 3 T-magnetic resonance imaging (MRI) and histological scans from the same brain hemisphere. The study encompassed 24 postmortem fetal brains (15-35 postconceptional weeks, PCW). The measurements were performed using Fiji and NDP.view2. We found that T2w MR signal-intensity curves show a specific regional and developmental stage profile already at 15 PCW. The MRI-histological correlation reveals that the subventricular-intermediate zone (SVZ-IZ) contributes the most to the regional differences in the MRI-profile and zone thicknesses, growing by a factor of 2.01 in the cingulate, and 1.78 in the neocortical wall. The interrelations of zone or wall thicknesses, obtained by both methods, disclose a different rate and extent of shrinkage per region (highest in neocortical subplate and SVZ-IZ) and stage (highest in the early second half of fetal development), distorting the zones' proportion in histological sections. This intrasubject, slice-matched, 3 T correlative MRI-histological study provides important information about regional development of the cortical wall, critical for the design of MRI criteria for prenatal brain monitoring and early detection of cortical or other brain pathologies in human fetuses.


Asunto(s)
Feto/embriología , Lóbulo Límbico/embriología , Neocórtex/embriología , Telencéfalo/embriología , Encéfalo/diagnóstico por imagen , Encéfalo/embriología , Encéfalo/patología , Feto/diagnóstico por imagen , Feto/patología , Edad Gestacional , Humanos , Ventrículos Laterales/diagnóstico por imagen , Ventrículos Laterales/embriología , Ventrículos Laterales/patología , Lóbulo Límbico/diagnóstico por imagen , Lóbulo Límbico/patología , Imagen por Resonancia Magnética , Neocórtex/diagnóstico por imagen , Neocórtex/patología , Tamaño de los Órganos , Telencéfalo/diagnóstico por imagen , Telencéfalo/patología
7.
Biomed Chromatogr ; 36(9): e5413, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35595284

RESUMEN

Passive permeability is one of the key features that determine absorbability and one of the most studied properties in the early phases of drug development. Newly synthesized succinimide derivatives from two different series (1-aryl-3-methylsuccinimides and 1-aryl-3-ethyl-3-methylsuccinimides) with high biological potential have been subjected to estimation of their passive permeability and their association with (a) experimentally obtained anisotropic lipophilicity, (b) in silico-calculated lipophilicity and (c) in silico-predicted permeability and absorbability. Non-cellular-based parallel artificial membrane permeability assay was applied for quantifying their passive permeation, expressed as logPapp . Passive permeation was governed by the lipophilicity of the analysed compounds, and anisotropic lipophilicity was related with statistically significant passive transcellular diffusion (r2 = 0.614, P < 0.001). Moreover, experimentally determined passive permeability, logPapp , was statistically significantly associated with both in silico-predicted absorption constant, ka (r2 = 0.7886, P < 0.001), and human intestinal absorption (HIA) in percentage (r2 = 0.484, P < 0.001), respectively. However, there was no statistically significant relationship between experimentally obtained permeability on non-cellular-based model and in silico-predicted Caco-2 permeability based on the predictions conducted on two different software. Based on the obtained results, anisotropic systems are promising surrogates for determining lipophilicity, except for compounds with acidic functional groups that are completely ionized under (pH = 7.4).


Asunto(s)
Anticonvulsivantes , Membranas Artificiales , Anticonvulsivantes/química , Células CACO-2 , Cromatografía Líquida de Alta Presión , Humanos , Permeabilidad , Succinimidas
8.
Int J Mol Sci ; 23(15)2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35897768

RESUMEN

The extracellular matrix (ECM) is an important regulator of excitability and synaptic plasticity, especially in its highly condensed form, the perineuronal nets (PNN). In patients with drug-resistant mesial temporal lobe epilepsy (MTLE), hippocampal sclerosis type 1 (HS1) is the most common histopathological finding. This study aimed to evaluate the ECM profile of HS1 in surgically treated drug-resistant patients with MTLE in correlation to clinical findings. Hippocampal sections were immunohistochemically stained for aggrecan, neurocan, versican, chondroitin-sulfate (CS56), fibronectin, Wisteria floribunda agglutinin (WFA), a nuclear neuronal marker (NeuN), parvalbumin (PV), and glial-fibrillary-acidic-protein (GFAP). In HS1, besides the reduced number of neurons and astrogliosis, we found a significantly changed expression pattern of versican, neurocan, aggrecan, WFA-specific glycosylation, and a reduced number of PNNs. Patients with a lower number of epileptic episodes had a less intense diffuse WFA staining in Cornu Ammonis (CA) fields. Our findings suggest that PNN reduction, changed ECM protein, and glycosylation expression pattern in HS1 might be involved in the pathogenesis and persistence of drug-resistant MTLE by contributing to the increase of CA pyramidal neurons' excitability. This research corroborates the validity of ECM molecules and their modulators as a potential target for the development of new therapeutic approaches to drug-resistant epilepsy.


Asunto(s)
Gliosis , Neurocano , Agrecanos/metabolismo , Matriz Extracelular/metabolismo , Gliosis/metabolismo , Hipocampo/metabolismo , Humanos , Neurocano/metabolismo , Esclerosis/metabolismo , Versicanos/metabolismo
9.
BMC Health Serv Res ; 21(1): 304, 2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33823866

RESUMEN

BACKGROUND: Rapid spread of COVID-19 forced the public to turn to community pharmacies as the most accessible points of primary healthcare, overloading pharmacy services. The objectives of this research were to detect and describe the changes in work environment of community pharmacists in Vojvodina during the state of emergency due to COVID-19 pandemic. Moreover, the COVID-19 pandemic effects on job related stress were assessed. METHODS: Community pharmacists from Vojvodina completed an online questionnaire on work environment changes related to COVID-19 (cross-sectional study). RESULTS: Out of the 1574 licenced pharmacists in Vojvodina, 392 completed the survey. Workload increase, reported by 90.8% of pharmacists, was caused mostly by higher demand for safety equipment, antiseptics and disinfectants, dietary products and medicines. Most pharmacists (93.1%) considered pharmacy workflow to be more complex than before the pandemic. Clients' behavior was described as less pleasant since the start of the pandemic by 67.6% of the community pharmacists. Many were concerned for their health and the health of their families (68.9%). Community pharmacists rated their stress levels higher if they i) were working in larger chains, ii) experienced clients' behavior as less pleasant or/and iii) were concerned for their/their family health. CONCLUSIONS: Current research pointed out the need for a more robust healthcare system which would allow rapid introduction of new activities and roles for community pharmacists that could possibly decrease job-related stress. Legal steps to improve the work environment in community pharmacies are necessary and urgent in order to fully utilize their skills and knowledge.


Asunto(s)
Adaptación Psicológica , COVID-19/psicología , Servicios Comunitarios de Farmacia , Farmacéuticos/psicología , Rol Profesional/psicología , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Pandemias/prevención & control , Farmacias , SARS-CoV-2 , Serbia/epidemiología
10.
Arch Pharm (Weinheim) ; 354(5): e2000416, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33491801

RESUMEN

Pinus nigra Arn. bark extracts from Mokra gora (MG) and Tara mountains were analyzed with regard to their polyphenolic profile and antioxidative and antiproliferative activity. The ethanol extract from MG showed the highest phenolic, flavonoid, tannin, and proanthocyanidin content when compared with the acetone and methanol extracts from both sites. The same extract exhibited the highest ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt) and ferric reducing antioxidant power (FRAP) radical scavenging ability and total antioxidant activity (TAA). On the basis of high-performance liquid chromatography analysis, catechin, caffeic, syringic, p-coumaric, and ferulic acids were predominantly present in the MG extracts. The ethanol extract from MG was rich in syringic acid, epicatechin and its derivatives, and ferulic acid and its derivatives. The bark extracts also exerted a high cytotoxic bioactivity against all evaluated cell lines (HeLa, MCF7, HT-29, and MRC-5). The antiproliferative activity of P. nigra bark is probably related to the ferulic acid content and its synergistic activity to caffeic acid and taxifolin. The antioxidative role of the presented phenols was confirmed through the obtained significant linear correlation between the total phenolic content and DPPH (r = .934) as well as the FRAP% of the extracts (r = .948). Also, the TAA significantly depended on the proanthocyanidins (r = .902) and tannin contents (r = .914). The composition of the presented compounds could be related to promising antioxidant and antiproliferative efficacy of MG bark.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Fitoquímicos/farmacología , Pinus/química , Extractos Vegetales/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Fitoquímicos/química , Fitoquímicos/aislamiento & purificación , Picratos/antagonistas & inhibidores , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Relación Estructura-Actividad
11.
Neuroimage ; 210: 116553, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-31972277

RESUMEN

The periventricular crossroads have been described as transient structures of the fetal brain where major systems of developing fibers intersect. The triangular parietal crossroad constitutes one major crossroad region. By combining in vivo and post-mortem fetal MRI with histological and immunohistochemical methods, we aimed to characterize these structures. Data from 529 in vivo and 66 post-mortem MRI examinations of fetal brains between gestational weeks (GW) 18-39 were retrospectively reviewed. In each fetus, the area adjacent to the trigone of the lateral ventricles at the exit of the posterior limb of the internal capsule (PLIC) was assessed with respect to signal intensity, size, and shape on T2-weighted images. In addition, by using in vivo diffusion tensor imaging (DTI), the main fiber pathways that intersect in these areas were identified. In order to explain the in vivo features of the parietal crossroads (signal intensity and developmental profile), we analyzed 23 post-mortem fetal human brains, between 16 and â€‹40 GW of age, processed by histological and immunohistochemical methods. The parietal crossroads were triangular-shaped areas with the base in the continuity of the PLIC, adjacent to the germinal matrix and the trigone of the lateral ventricles, with the tip pointing toward the subplate. These areas appeared hyperintense to the subplate, and corresponded to a convergence zone of the developing external capsule, the PLIC, and the fronto-occipital association fibers. They were best detected between GW 25-26, and, at term, they became isointense to the adjacent structures. The immunohistochemical results showed a distinct cellular, fibrillar, and extracellular matrix arrangement in the parietal crossroads, depending on the stage of development, which influenced the MRI features. The parietal crossroads are transient, but important structures in white matter maturation and their damage may be indicative of a poor prognosis for a fetus with regard to neurological development. In addition, impairment of this region may explain the complex neurodevelopmental deficits in preterm infants with periventricular hypoxic/ischemic or inflammatory lesions.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Vías Nerviosas , Neuroimagen/métodos , Diagnóstico Prenatal/métodos , Telencéfalo , Sustancia Blanca , Autopsia , Imagen de Difusión Tensora/métodos , Femenino , Feto , Edad Gestacional , Humanos , Inmunohistoquímica , Cápsula Interna/anatomía & histología , Cápsula Interna/diagnóstico por imagen , Cápsula Interna/enzimología , Vías Nerviosas/anatomía & histología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/embriología , Embarazo , Telencéfalo/anatomía & histología , Telencéfalo/diagnóstico por imagen , Telencéfalo/embriología , Sustancia Blanca/anatomía & histología , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/embriología
12.
Cereb Cortex ; 29(11): 4709-4724, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-30722016

RESUMEN

To uncover the ontogenesis of the human indusium griseum (IG), 28 post-mortem fetal human brains, 12-40 postconceptional weeks (PCW) of age, and 4 adult brains were analyzed immunohistochemically and compared with post-mortem magnetic resonance imaging (MRI) of 28 fetal brains (14-41 PCW). The morphogenesis of the IG occurred between 12 and 15 PCW, transforming the bilateral IG primordia into a ribbon-like cortical lamina. The histogenetic transition of sub-laminated zones into the three-layered cortical organization occurred between 15 and 35 PCW, concomitantly with rapid cell differentiation that occurred from 18 to 28 PCW and the elaboration of neuronal connectivity during the entire second half of gestation. The increasing number of total cells and neurons in the IG at 25 and 35 PCW confirmed its continued differentiation throughout this period. High-field 3.0 T post-mortem MRI enabled visualization of the IG at the mid-fetal stage using T2-weighted sequences. In conclusion, the IG had a distinct histogenetic differentiation pattern than that of the neighboring intralimbic areas of the same ontogenetic origin, and did not show any signs of regression during the fetal period or postnatally, implying a functional role of the IG in the adult brain, which is yet to be disclosed.


Asunto(s)
Lóbulo Límbico/citología , Lóbulo Límbico/embriología , Neuronas/citología , Neuronas/fisiología , Recuento de Células , Diferenciación Celular , Femenino , Técnicas Histológicas , Humanos , Imagen por Resonancia Magnética , Masculino
13.
J Cell Mol Med ; 23(2): 1602-1607, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30488668

RESUMEN

Cell-adhesion glycoprotein neuroplastin (Np) is involved in the regulation of synaptic plasticity and balancing hippocampal excitatory/inhibitory inputs which aids in the process of associative memory formation and learning. Our recent findings show that neuroplastin expression in the adult human hippocampus is specifically associated with major hippocampal excitatory pathways and is related to neuronal calcium regulation. Here, we investigated the hippocampal expression of brain-specific neuroplastin isoform (Np65), its relationship with amyloid and tau pathology in Alzheimer's disease (AD), and potential involvement of neuroplastin in tissue response during the disease progression. Np65 expression and localization was analysed in six human hippocampi with confirmed AD neuropathology, and six age-/gender-matched control hippocampi by imunohistochemistry. In AD cases with shorter disease duration, the Np65 immunoreactivity was significantly increased in the dentate gyrus (DG), Cornu Ammonis 2/3 (CA2/3), and subiculum, with the highest level of Np expression being located on the dendrites of granule cells and subicular pyramidal neurons. Changes in the expression of neuroplastin in AD hippocampal areas seem to be related to the progression of disease. Our study suggests that cell-adhesion protein neuroplastin is involved in tissue reorganization and is a potential molecular marker of plasticity response in the early neurodegeneration process of AD.


Asunto(s)
Enfermedad de Alzheimer/genética , Hipocampo/metabolismo , Glicoproteínas de Membrana/genética , Plasticidad Neuronal/genética , Neuronas/metabolismo , Proteínas tau/genética , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Amiloide/genética , Amiloide/metabolismo , Autopsia , Calcio/metabolismo , Señalización del Calcio , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Expresión Génica , Hipocampo/patología , Humanos , Masculino , Glicoproteínas de Membrana/metabolismo , Neuronas/patología , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Sinapsis/genética , Sinapsis/metabolismo , Sinapsis/patología , Transmisión Sináptica/genética , Proteínas tau/metabolismo
14.
J Anat ; 235(3): 670-686, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31070791

RESUMEN

The early development and growth of the corpus callosum are supported by several midline transient structures in mammals that include callosal septa (CS), which are present only in the second half of gestation in humans. Here we provide new data that support the guidance role of CS in corpus callosum development, derived from the analysis of 46 postmortem fetal brains, ranging in age from 16 to 40 post conception weeks (PCW). Using immunohistochemical methods, we show the expression pattern of guidance cues ephrinA4 and neogenin, extracellular protein fibronectin, as well as non-activated microglia in the CS. We found that the dynamic changes in expression of guidance cues, cellular and extracellular matrix constituents in the CS correlate well with the growth course of the corpus callosum at midsagittal level. The CS reach and maintain their developmental maximum between 20 and 26 PCW and can be visualized as hypointense structures in the ventral callosal portion with ex vivo (in vitro) T2-weighted 3T magnetic resonance imaging (MRI). The maximum of septal development overlaps with an increase in the callosal midsagittal area, whereas the slow, gradual resolution of CS coincides with a plateau of midsagittal callosal growth. The recognition of CS existence in human fetal brain and the ability to visualize them by ex vivoMRI attributes a potential diagnostic value to these transient structures, as advancement in imaging technologies will likely also enable in vivoMRI visualization of the CS in the near future.


Asunto(s)
Cuerpo Calloso/embriología , Edad Gestacional , Humanos
15.
J Anat ; 235(3): 651-669, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31435943

RESUMEN

Von Economo neurons (VENs) are modified pyramidal neurons characterized by an extremely elongated rod-shaped soma. They are abundant in layer V of the anterior cingulate cortex (ACC) and fronto-insular cortex (FI) of the human brain, and have long been described as a human-specific neuron type. Recently, VENs have been reported in the ACC of apes and the FI of macaque monkeys. The first description of the somato-dendritic morphology of VENs in the FI by Cajal in 1899 (Textura del Sistema Nervioso del Hombre y de los Vertebrados, Tomo II. Madrid: Nicolas Moya) strongly suggested that they were a unique neuron subtype with specific morphological features. It is surprising that a clarification of this extremely important observation has not yet been attempted, especially as possible misidentification of other oval or fusiform cells as VENs has become relevant in many recently published studies. Here, we analyzed sections of Brodmann area 24 (ACC) stained with rapid Golgi and Golgi-Cox in five adult human specimens, and confirmed Cajal's observations. In addition, we established a comprehensive morphological description of VENs. VENs have a distinct somato-dendritic morphology that allows their clear distinction from other modified pyramidal neurons. We established that VENs have a perpendicularly oriented, stick-shaped core part consisting of the cell body and two thick extensions - an apical and basal stem. The perpendicular length of the core part was 150-250 µm and the thickness was 10-21 µm. The core part was characterized by a lack of clear demarcation between the cell body and the two extensions. Numerous thin, spiny and horizontally oriented side dendrites arose from the cell body. The basal extension of the core part typically ended by giving numerous smaller dendrites with a brush-like branching pattern. The apical extension had a topology typical for apical dendrites of pyramidal neurons. The dendrites arising from the core part had a high dendritic spine density. The most distinct feature of VENs was the distant origin site of the axon, which arose from the ending of the basal extension, often having a common origin with a dendrite. Quantitative analysis found that VENs could be divided into two groups based on total dendritic length - small VENs with a peak total dendritic length of 1500-2500 µm and large VENs with a peak total dendritic length of 5000-6000 µm. Comparative morphological analysis of VENs and other oval and fusiform modified pyramidal neurons showed that on Nissl sections small VENs might be difficult to identify, and that oval and fusiform neurons could be misidentified as VENs. Our analysis of Golgi slides of Brodmann area 9 from a total of 32 adult human subjects revealed only one cell resembling VEN morphology. Thus, our data show that the numerous recent reports on the presence of VENs in non-primates in other layers and regions of the cortex need further confirmation by showing the dendritic and axonal morphology of these cells. In conclusion, our study provides a foundation for further comprehensive morphological and functional studies on VENs between different species.


Asunto(s)
Giro del Cíngulo/citología , Células Piramidales/citología , Adolescente , Adulto , Humanos , Masculino , Persona de Mediana Edad , Coloración y Etiquetado
17.
Cereb Cortex ; 26(12): 4574-4589, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-26428952

RESUMEN

Work on rodents demonstrated that steep upregulation of KCC2, a neuron-specific Cl- extruder of cation-chloride cotransporter (CCC) family, commences in supraspinal structures at around birth, leading to establishment of hyperpolarizing GABAergic responses. We describe spatiotemporal expression profiles of the entire CCC family in human brain. KCC2 mRNA was observed already at 10th postconceptional week (PCW) in amygdala, cerebellum, and thalamus. KCC2-immunoreactive (KCC2-ir) neurons were abundant in subplate at 18 PCW. By 25 PCW, numerous subplate and cortical plate neurons became KCC2-ir. The mRNA expression profiles of α- and ß-isoforms of Na-K ATPase, which fuels cation-chloride cotransport, as well of tropomyosin receptor kinase B (TrkB), which promotes developmental upregulation of KCC2, were consistent with data from studies on rodents about their interactions with KCC2. Thus, in human brain, expression of KCC2 and its functionally associated proteins begins in early fetal period. Our work facilitates translation of results on CCC functions from animal studies to human and refutes the view that poor efficacy of anticonvulsants in the term human neonate is attributable to the lack of KCC2. We propose that perinatally low threshold for activation of Ca2+-dependent protease calpain renders neonates susceptible to downregulation of KCC2 by traumatic events, such as perinatal hypoxia ischemia.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Encéfalo/metabolismo , Simportadores/metabolismo , Adulto , Anciano de 80 o más Años , Encéfalo/citología , Niño , Regulación del Desarrollo de la Expresión Génica , Humanos , Inmunohistoquímica , Lactante , Recién Nacido , Glicoproteínas de Membrana/metabolismo , Análisis por Micromatrices , Persona de Mediana Edad , ARN Mensajero/metabolismo , Receptor trkB/metabolismo , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Miembro 2 de la Familia de Transportadores de Soluto 12/metabolismo , Adulto Joven , Cotransportadores de K Cl
18.
Int J Environ Health Res ; 27(1): 11-26, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27771963

RESUMEN

Bisphenol A (BPA) is a ubiquitous environmental pollutant which is often associated with various health issues. In this study 103 healthy female volunteers in reproductive age from Serbian north province Vojvodina were enrolled and examined for the BPA exposure in the urine samples after 12 h of fasting. BPA was found in 35.92 % (37/103) of subjects. Statistically significant increment in waist circumference (p = 0.045) and waist-to-height ratio (p = 0.037) was observed among the BPA positive women in comparison with the women who had the same energetic balance and had not been exposed to BPA. Linear correlation was obtained between the BPA concentration in urine samples and body mass index (r2 = 0.35, p = 0.003) waist circumference (r2 = 0.21, p = 0.02) and waist-to-height ratio (r2 = 0.25, p = 0.01) among the obese. High energetic intake and reduced physical activity additionally pronounced BPA positive association with obesity. No statistically significant difference was observed in triglycerides, HDL and LDL cholesterol levels between the BPA exposed and BPA non-exposed female volunteers.


Asunto(s)
Compuestos de Bencidrilo/orina , Exposición a Riesgos Ambientales , Contaminantes Ambientales/orina , Obesidad/epidemiología , Fenoles/orina , Adolescente , Adulto , Compuestos de Bencidrilo/toxicidad , Estudios Transversales , Monitoreo del Ambiente , Contaminantes Ambientales/toxicidad , Femenino , Humanos , Persona de Mediana Edad , Obesidad/inducido químicamente , Obesidad Abdominal/inducido químicamente , Obesidad Abdominal/epidemiología , Fenoles/toxicidad , Factores de Riesgo , Serbia/epidemiología , Adulto Joven
19.
Environ Monit Assess ; 190(1): 17, 2017 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-29234897

RESUMEN

Phthalates are ubiquitous environmental contaminants, massively used in industry as plasticizers and additives in cosmetics, which may impair the human endocrine system inducing fertility problems, respiratory diseases, obesity, and neuropsychological disorders. The aim of this study was to examine the influence of the monoethyl phthalate (MEP) and mono-(2-ethylhexyl) phthalate (MEHP) on the liver function and cardiometabolic risk factors in males. In this research, 102 male participants (51 normal weight and 51 overweight/obese) were enrolled and examined for phthalate metabolites exposure in urine samples after 12 h of fasting. MEP was found in 28.43% (29/102) volunteers, while MEHP was detected among 20.59% (21/102) participants. Statistically significant increment in transaminase serum levels was observed in MEP-positive normal weight subgroup. Linear correlation was obtained between MEP concentration in urine samples and triglyceride (TG) serum levels (r 2 = 0.33; p < 0.01), visceral adiposity index (VAI) (r 2 = 0.41; p < 0.01), lipid accumulation product (LAP) (r 2 = 0.32; p < 0.01), and TG to high-density lipoprotein (HDL) ratio (r 2 = 0.40, p < 0.01) among the obese. The MEHP-positive normal weight volunteers had statistically significant increment of body mass index (p = 0.03) compared to MEHP-negative participants. Urine MEHP concentrations were negatively correlated with HDL serum levels (r 2 = 0.31; p < 0.05) in the normal weight subgroup. The phthalates exposure may be related to statistically significant ALT and AST serum levels increment as well as with increased BMI, while the phthalate levels in the urine may be correlated with increased TG and decreased HDL cholesterol serum levels and associated with indicators of cardiometabolic risk and insulin resistance as LAP and VAI.


Asunto(s)
Enfermedades Cardiovasculares/metabolismo , Disruptores Endocrinos/toxicidad , Exposición a Riesgos Ambientales/análisis , Hígado/efectos de los fármacos , Obesidad/metabolismo , Ácidos Ftálicos/toxicidad , Adolescente , Adulto , Biomarcadores/orina , Índice de Masa Corporal , Enfermedades Cardiovasculares/orina , Estudios Transversales , Dietilhexil Ftalato/análogos & derivados , Dietilhexil Ftalato/toxicidad , Dietilhexil Ftalato/orina , Disruptores Endocrinos/orina , Humanos , Hígado/metabolismo , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Obesidad/orina , Ácidos Ftálicos/orina , Riesgo , Adulto Joven
20.
Mol Cell Neurosci ; 69: 12-21, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26370173

RESUMEN

Understanding the intra- and extracellular proteins involved in the development of the corticospinal tract (CST) may offer insights into how the pathway could be regenerated following traumatic spinal cord injury. Currently, however, little is known about the proteome of the developing corticospinal system. The present study, therefore, has used quantitative proteomics and bioinformatics to detail the protein profile of the rat CST during its formation in the spinal cord. This analysis identified increased expression of 65 proteins during the early ingrowth of corticospinal axons into the spinal cord, and 36 proteins at the period of heightened CST growth. A majority of these proteins were involved in cellular assembly and organization, with annotations being most highly associated with cytoskeletal organization, microtubule dynamics, neurite outgrowth, and the formation, polymerization and quantity of microtubules. In addition, 22 proteins were more highly expressed within the developing CST in comparison to other developing white matter tracts of the spinal cord of age-matched animals. Of these differentially expressed proteins, only one, stathmin 1 (a protein known to be involved in microtubule dynamics), was both highly enriched in the developing CST and relatively sparse in other developing descending and ascending spinal tracts. Immunohistochemical analyses of the developing rat spinal cord and fetal human brain stem confirmed the enriched pattern of stathmin expression along the developing CST, and in vitro growth assays of rat corticospinal neurons showed a reduced length of neurite processes in response to pharmacological perturbation of stathmin activity. Combined, these findings suggest that stathmin activity may modulate axonal growth during development of the corticospinal projection, and reinforces the notion that microtubule dynamics could play an important role in the generation and regeneration of the CST.


Asunto(s)
Axones/metabolismo , Regeneración Nerviosa/fisiología , Neuritas/metabolismo , Neuronas/citología , Tractos Piramidales/metabolismo , Estatmina/metabolismo , Animales , Ratas Sprague-Dawley , Traumatismos de la Médula Espinal/metabolismo
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