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1.
AJOG Glob Rep ; 2(4): 100080, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36536849

RESUMEN

BACKGROUND: Occiput posterior is the most common malposition in labor. Deliveries in occiput posterior position have been shown to have higher rates of adverse short-term maternal and neonatal outcomes compared with deliveries in occiput anterior position. There are no guidelines providing recommendations nor summarizing risks of adverse outcomes by delivery method to inform the decision-making process in occiput posterior delivery management. Population-based studies examining the outcomes associated with various management processes of occiput posterior position at the time of labor or delivery are lacking. OBJECTIVE: This study aimed to describe the current management of term singleton occiput posterior deliveries in British Columbia, Canada and to examine the association between different management strategies and adverse outcomes by describing the rates of: occiput posterior malposition; and spontaneous vaginal delivery, operative vaginal delivery, and cesarean delivery from occiput posterior malposition. We also analyzed the rates of adverse labor and delivery outcomes stratified by fetal position and delivery mode, and the interaction effect of occiput posterior position and delivery mode on the rates of adverse outcomes. STUDY DESIGN: This was a retrospective cohort study of cephalic term singleton deliveries in British Columbia from 2004 to 2020, using the British Columbia Perinatal Data Registry. The obstetrical adverse outcome index (a composite of 10 adverse maternal or neonatal events), adverse outcome index subcomponent rates, and adverse outcome index-derived weighted scores were compared between deliveries stratified by fetal position at delivery (occiput posterior or occiput anterior) and occiput posterior deliveries stratified by delivery method. Multivariable log-binomial logistic regression was used to model the adverse outcome index score. RESULTS: Of 306,237 term births, 19% had occiput posterior position during labor, 37% of which persisted in occiput posterior position at delivery. Among occiput posterior deliveries, 27% were spontaneous vaginal deliveries, 8% vacuum, 5% forceps, 1% mixed vacuum-forceps, and 59% were cesarean delivery; this distribution differed from that of occiput anterior deliveries (P<.0001). Overall, adverse outcome index scores were significantly higher in persistent occiput posterior deliveries (8.8% had ≥1 adverse outcomes; adjusted rate ratio, 1.07 [1.01-1.14]) than in occiput posterior labors that rotated to occiput anterior deliveries; the most frequent adverse outcome was third- or fourth-degree lacerations. Neonatal adverse outcomes were also more frequent in occiput posterior delivery (4.3% vs 3.3%; adjusted rate ratio, 1.21 [1.10-1.35]), whereas maternal outcomes were similar between groups (4.8% vs 6.0%; adjusted rate ratio, 1.04 [0.96-1.13]). Among persistent occiput posterior deliveries, spontaneous vaginal delivery and cesarean delivery had the lowest proportion of deliveries with ≥1 adverse outcomes (6.1% and 6.2%), whereas forceps deliveries had the highest (38.1%); the largest contributor to the adverse outcomes were third- or fourth-degree lacerations. Among occiput posterior deliveries with any adverse outcome, cesarean delivery had the highest Severity Index score, due in part to the inclusion of third- or fourth-degree tears (which are assigned a comparatively low score) as the most common adverse event in the other vaginal delivery modes, and because of outcomes with a higher severity score being associated with cesarean delivery, such as uterine rupture (a reason for cesarean delivery) and intensive care unit admission (an outcome following cesarean delivery). Overall, in a multivariable regression model, delivery mode and the interaction between delivery mode and occiput posterior position were significant predictors of a delivery with ≥1 adverse outcomes, whereas occiput posterior position itself was not. CONCLUSION: One in five singleton deliveries at term gestation had occiput posterior position in labor; most of these rotated to occiput anterior by delivery, which had better outcomes than persistent occiput posterior deliveries. Among the latter, spontaneous vaginal delivery and cesarean delivery had the lowest frequency of adverse outcomes, whereas forceps deliveries had the highest. This study provides a robust updated analysis of birth outcomes following different occiput posterior management strategies, which can inform provider decision-making and counseling. Its observational design may limit its use for direct recommendations for management of occiput posterior malposition, yet the study helps to define the risks associated with different modes of delivery in the setting of occiput posterior malposition. With additional studies examining success rates of intermediate occiput posterior-occiput anterior rotation, other delivery management steps, and long-term outcomes, this study helps to define safe management of occiput posterior delivery.

2.
Mil Med ; 186(Suppl 1): 76-81, 2021 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-33499495

RESUMEN

BACKGROUND: Respiratory viruses are an important cause of nonbattle injury disease and contribute to the top seven reasons for medical encounters. In the absence of vaccines that provide complete protection against these viruses, viral surveillance can identify disease burden and target virus-specific preventative measures. Influenza infection, in particular, has significant adverse effects on force readiness. METHODS: We tracked the frequency of 16 respiratory viruses at Walter Reed National Military Medical Center tested for during routine patient care using multiplex polymerase chain reaction and rapid antigen testing. We collected data on the date and location of the testing, as well as the age of the individual tested from two consecutive respiratory viral seasons. RESULTS: During the first year of data compilation (2017-2018), 2556 tests were performed; 342 (13.4%) were positive for influenza A and 119 (4.7%) were positive for influenza B. After influenza, the most common families of viruses identified were rhino/enterovirus (490 [19.2%]). During the second year (2018-2019), 4,458 tests were run; 564 (12.7%) were positive for influenza A and 35 (0.79%) were positive for influenza B, while rhino/enterovirus was identified in 690 (15.4%). Influenza peaked early during the 2017-2018 season and later during the 2018-2019 season. Importantly, during the 2017-2018 season, the vaccine was less effective for the H3N2 strain circulating that year and viral surveillance quickly identified a hospital-specific outbreak and a larger disease burden. This was in contrast to the 2018-2019 vaccine which exhibited higher effectiveness for circulating strains. CONCLUSION: Our data highlight the seasonality of respiratory viruses with a focus on influenza. By tracking respiratory viruses in Department of Defense communities, we may be able to predict when influenza may cause the greatest burden for distinct organizational regions and prescribe with greater precision preventative protocols by location, as well as rapidly determine vaccine efficacy. Our current data suggest that when vaccine strains are mismatched, rapid upfront targeting of antivirals may be warranted, but when the vaccine strains are better matched, late season peaks of disease may indicate waning immunity and should be monitored.


Asunto(s)
Gripe Humana , Costo de Enfermedad , Humanos , Subtipo H3N2 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/uso terapéutico , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Salud Pública , Estaciones del Año
3.
J Interpers Violence ; 36(15-16): NP8800-NP8823, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-31046528

RESUMEN

Individuals often tend to irrationally blame victims for their plight. This research incorporated a bounded rationality framework to examine first-person perspectives (rather than third-person) of both victims' and nonvictims' perceptions and judgments of acquaintance and stranger sexual violence. Upon completing individual difference measures, including a just-world belief assessment, participants (N = 296) were randomly assigned to read a scenario in which the vignette victim was either acquainted with or had no prior relationship with the perpetrator. Then, taking the perspective of the vignette victim, participants offered four judgments: the likelihood of reporting the crime, self-blame, perceived control, and sympathy expected from others. Results showed that instances of acquaintance sexual violence were judged more negatively than instances of stranger sexual violence. Moreover, participants who had previously experienced sexual violence reported more negative judgments than nonvictims (except for sympathy expected from others). An exploratory path analysis indicated that as nonvictims', but not victims', just-world beliefs became stronger, they indicated a higher willingness to report the crime, perceived more control over the situation, and expected more sympathy from others. We end with a discussion of how the present research can advance our understanding of sexual violence by using a bounded rationality framework and discuss the practical implications that the observed effects have for professionals in the legal system, outside observers, and victims themselves.


Asunto(s)
Acoso Escolar , Víctimas de Crimen , Delitos Sexuales , Crimen , Humanos , Juicio
4.
Fed Pract ; 38(12): e77-e79, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35177892

RESUMEN

Diagnosis of pulmonary nodules requires an in-depth workup, including clinical evaluation, laboratory and pulmonary functions tests, and imaging, which helped to identify in this patient pulmonary rheumatoid arthritis, an important factor in patient mortality.

5.
J Neurosci ; 30(41): 13883-94, 2010 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-20943929

RESUMEN

Previous studies have defined a requirement for Sonic hedgehog (Shh) signaling in patterning the ventral telencephalon, a major source of the neuronal diversity found in the mature telencephalon. The zinc finger transcription factor Gli3 is a critical component of the Shh signaling pathway and its loss causes major defects in telencephalic development. Gli3 is expressed in a graded manner along the dorsoventral axis of the telencephalon but it is unknown whether Gli3 expression levels are important for dorsoventral telencephalic patterning. To address this, we used the Gli3 hypomorphic mouse mutant Polydactyly Nagoya (Pdn). We show that in Pdn/Pdn embryos, the telencephalic expression of Gli3 remains graded, but Gli3 mRNA and protein levels are reduced, resulting in an upregulation of Shh expression and signaling. These changes mainly affect the development of the lateral ganglionic eminence (LGE), with some disorganization of the medial ganglionic eminence mantle zone. The pallial/subpallial boundary is shifted dorsally and the production of postmitotic neurons is reduced. Moreover, LGE pioneer neurons that guide corticofugal axons into the LGE do not form properly, delaying the entry of corticofugal axons into the ventral telencephalon. Pdn/Pdn mutants also show severe pathfinding defects of thalamocortical axons in the ventral telencephalon. Transplantation experiments demonstrate that the intrinsic ability of the Pdn ventral telencephalon to guide thalamocortical axons is compromised. We conclude that correct Gli3 levels are particularly important for the LGE's growth, patterning, and development of axon guidance capabilities.


Asunto(s)
Axones/metabolismo , Tipificación del Cuerpo/fisiología , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Telencéfalo/crecimiento & desarrollo , Animales , Western Blotting , Inmunohistoquímica , Hibridación in Situ , Factores de Transcripción de Tipo Kruppel/genética , Ratones , Ratones Transgénicos , Proteínas del Tejido Nervioso/genética , Neuronas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Telencéfalo/metabolismo , Proteína Gli3 con Dedos de Zinc
6.
ASN Neuro ; 1(4)2009 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-19807694

RESUMEN

The present study delineates the cellular responses of dorsal pallium to targeted genetic ablation of the principal preplate neurons of the neocortex. Ganciclovir treatment during prenatal development (E11-E13; where E is embryonic day) of mice selectively killed cells with shared S-phase vulnerability and targeted expression of a GPT [golli promoter transgene, linked to HSV-TK (herpes simplex virus-thymidine kinase), τ-eGFP (τ-enhanced green fluorescent protein) and lacZ (lacZ galactosidase) reporters] localized in preplate neurons. Morphogenetic fates of attacked neurons and neuroblasts, and their successors, were assessed by multiple labelling in time-series comparisons between ablated (HSV-TK+/0) and control (HSV-TK0/0) littermates. During ablation generation, neocortical growth was suppressed, and compensatory reorganization of non-GPT ventricular zone progenitors of dorsal pallium produced replacements for killed GPT neuroblasts. Replacement and surviving GPT neuroblasts then produced replacements for killed GPT neurons. Near-normal restoration of their complement delayed the settlement of GPT neurons into the reconstituted preplate, which curtailed the outgrowth of pioneer corticofugal axons. Based on this evidence, we conclude that specific cell killing in ablated mice can eliminate a major fraction of GPT neurons, with insignificant bystander killing. Also, replacement GPT neurons in ablated mice originate exclusively by proliferation from intermediate progenitor GPT neuroblasts, whose complement is maintained by non-GPT progenitors for inductive regulation of the total complement of GPT neurons. Finally, GPT neurons in both normal and ablated mice meet all morphogenetic criteria, including the 'outside-in' vertical gradient of settlement, presently used to identify principal preplate neurons. In ablated mice, delayed organization of these neurons desynchronizes and isolates developing neocortex from the rest of the brain, and permanently impairs its connectivity.

7.
ASN Neuro ; 1(4)2009 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-19715557

RESUMEN

Recently, several in vitro studies have shown that the golli-myelin basic proteins regulate Ca2+ homoeostasis in OPCs (oligodendrocyte precursor cells) and immature OLs (oligodendrocytes), and that a number of the functions of these cells are affected by cellular levels of the golli proteins. To determine the influence of golli in vivo on OL development and myelination, a transgenic mouse was generated in which the golli isoform J37 was overexpressed specifically within OLs and OPCs. The mouse, called JOE (J37-overexpressing), is severely hypomyelinated between birth and postnatal day 50. During this time, it exhibits severe intention tremors that gradually abate at later ages. After postnatal day 50, ultrastructural studies and Northern and Western blot analyses indicate that myelin accumulates in the brain, but never reaches normal levels. Several factors appear to underlie the extensive hypomyelination. In vitro and in vivo experiments indicate that golli overexpression causes a significant delay in OL maturation, with accumulation of significantly greater numbers of pre-myelinating OLs that fail to myelinate axons during the normal myelinating period. Immunohistochemical studies with cell death and myelin markers indicate that JOE OLs undergo a heightened and extended period of cell death and are unable to effectively myelinate until 2 months after birth. The results indicate that increased levels of golli in OPC/OLs delays myelination, causing significant cell death of OLs particularly in white matter tracts. The results provide in vivo evidence for a significant role of the golli proteins in the regulation of maturation of OLs and normal myelination.

8.
J Physiol ; 587(Pt 9): 1903-15, 2009 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-19289548

RESUMEN

In the Golli-tau-eGFP (GTE) transgenic mouse the reporter gene expression is largely confined to the layer of subplate neurons (SPn), providing an opportunity to study their intracortical and extracortical projections. In this study, we examined the thalamic afferents and layer IV neuron patterning in relation to the SPn neurites in the developing barrel cortex in GTE mouse at ages embryonic day 17 (E17) to postnatal day 14 (P14). Serotonin transporter immunohistochemistry or cytochrome oxydase histochemistry was used to reveal thalamic afferent patterning. Bizbenzimide staining identified the developing cytoarchitecture in coronal and tangential sections of GTE brains. Enhanced green fluorescent protein (GFP)-labelled neurites and thalamic afferents were both initially diffusely present in layer IV but by P4-P6 both assumed the characteristic periphery-related pattern and became restricted to the barrel hollows. This pattern gradually changed and by P10 the GFP-labelled neurites largely accumulated at the layer IV-V boundary within the barrel septa whereas thalamic afferents remained in the hollows. To investigate whether this reorganisation is dependent on sensory input, the whiskers of row 'a' or 'c' were removed at P0 or P5 and the organisation of GFP-labelled neurites in the barrel cortex was examined at P6 or P10. In the contralateral region corresponding to row 'a' or 'c' the lack of hollow to septa rearrangement of the GFP-labelled neurites was observed after P0 row removal at P10 but not at P6. Our findings suggest a dynamic, sensory periphery-dependent integration of SPn neurites into the primary somatosensory cortex during the period of barrel formation.


Asunto(s)
Ratones Transgénicos/fisiología , Modelos Neurológicos , Red Nerviosa/fisiología , Proteínas del Tejido Nervioso/metabolismo , Neuronas/fisiología , Proteínas Nucleares/metabolismo , Sinapsis/fisiología , Proteínas tau/metabolismo , Animales , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Ratones , Proteínas del Tejido Nervioso/genética , Proteínas Nucleares/genética , Proteínas tau/genética
9.
J Rheumatol ; 36(2): 315-22, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19132787

RESUMEN

OBJECTIVE: Sequence variation in gene promoters is often associated with disease risk. We tested the hypothesis that common promoter variation in the APOH gene (encoding for ss(2)-glycoprotein I) is associated with systemic lupus erythematosus (SLE) risk and SLE-related clinical phenotypes in a Caucasian cohort. METHODS: We used a case-control design and genotyped 345 women with SLE and 454 healthy control women for 8 APOH promoter single-nucleotide polymorphisms (SNP; -1284C>G, -1219G>A, -1190G>C, -759A>G, -700C>A, -643T>C, -38G>A, and -32C>A).Association analyses were performed on single SNP and haplotypes. Haplotype analyses were performed using EH (Estimate Haplotype-frequencies) and Haploview programs. In vitro reporter gene assay was performed in COS-1 cells. Electrophoretic mobility shift assay (EMSA) was performed using HepG2 nuclear cells. RESULTS: Overall haplotype distribution of the APOH promoter SNP was significantly different between cases and controls (p = 0.009). The -643C allele was found to be protective against carotid plaque formation (adjusted OR 0.37, p = 0.013) among patients with SLE. The -643C allele was associated with a ~2-fold decrease in promoter activity as compared to wild-type -643T allele (mean +/- standard deviation: 3.94 +/- 0.05 vs 6.99 +/- 0.68, p = 0.016). EMSA showed that the -643T>C SNP harbors a binding site for a nuclear factor. The -1219G>A SNP showed a significant association with the risk of lupus nephritis (age-adjusted OR 0.36, p = 0.016). CONCLUSION: Our data indicate that APOH promoter variants may be involved in the etiology of SLE, especially the risk for autoimmune-mediated cardiovascular disease.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Lupus Eritematoso Sistémico/genética , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genética , beta 2 Glicoproteína I/genética , Adulto , Sitios de Unión/genética , Estenosis Carotídea/epidemiología , Estenosis Carotídea/genética , Estenosis Carotídea/metabolismo , Estudios de Casos y Controles , Estudios de Cohortes , Comorbilidad , Análisis Mutacional de ADN , Ensayo de Cambio de Movilidad Electroforética , Femenino , Frecuencia de los Genes/genética , Pruebas Genéticas , Haplotipos , Humanos , Lupus Eritematoso Sistémico/epidemiología , Lupus Eritematoso Sistémico/metabolismo , Nefritis Lúpica/epidemiología , Nefritis Lúpica/genética , Nefritis Lúpica/metabolismo , Persona de Mediana Edad , Fenotipo
10.
Eur J Neurosci ; 25(1): 17-30, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17241263

RESUMEN

The first postmitotic neurons in the developing neocortex establish the preplate layer. These early-born neurons have a significant influence on the circuitry of the developing cortex. However, the exact timing and trajectory of their projections, between cortical hemispheres and intra- and extra-cortical regions, remain unresolved. Here, we describe the creation of a transgenic mouse using a 1.3 kb golli promoter element of the myelin basic protein gene to target expression of a tau-green fluorescent protein (GFP) fusion protein in the cell bodies and processes of pioneer cortical neurons. During embryonic and early neonatal development, the timing and patterning of process extension from these neurons was examined. Analysis of tau-GFP fluorescent fibers revealed that progression of early labeled projections was interrupted unexpectedly by transient pauses at the corticostriatal and telencephalic-diencephalic boundaries before invading the thalamus just prior to birth. After birth the pioneering projections differentially invaded the thalamus, excluding some nuclei, e.g. medial and lateral geniculate, until postnatal days 10-14. Early labeled projections were also found to cross to the contralateral hemisphere as well as to the superior colliculus. These results indicate that early corticothalamic projections appear to pause before invading specific subcortical regions during development, that there is developmental regulation of innervation of individual thalamic nuclei, and that these early-generated neurons also establish early projections to commissural and subcortical targets.


Asunto(s)
Corteza Cerebral/embriología , Corteza Cerebral/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica/fisiología , Vías Nerviosas , Proteínas tau/metabolismo , Animales , Animales Recién Nacidos , Mapeo Encefálico , Recuento de Células/métodos , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Embrión de Mamíferos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Inmunohistoquímica , Hibridación in Situ , Ratones , Ratones Transgénicos , Proteínas del Tejido Nervioso/metabolismo , Vías Nerviosas/embriología , Vías Nerviosas/crecimiento & desarrollo , Vías Nerviosas/metabolismo , Neuronas/metabolismo , Proteínas tau/genética
11.
Novartis Found Symp ; 288: 212-24; discussion 224-9, 276-81, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18494261

RESUMEN

Building the brain is like erecting a house of cards. The early connections provide the foundation of the adult structure, and disruption of these may be the source of many developmental flaws. Cerebral cortical developmental disorders (including schizophrenia and autism) and perinatal injuries involve cortical neurons with early connectivity. The major hindrance of progress in understanding the early neural circuits during cortical development and disease has been the lack of reliable markers for specific cell populations. Due to the advance of powerful approaches in gene expression analysis and the utility of models with reporter gene expressions in specific cortical cell types, our knowledge of the early cortical circuits is rapidly increasing. With focus on the sub-plate, layer VI and layer V projection neurons, we shall illustrate the progress made in the understanding of their neurochemical properties, physiological characteristics and their integration into the early intracortical and extracortical circuitry. This field benefited from recent developments in mouse genetics in generating models with subtype specific gene expression patterns, powerful cell dissection and separation methods combined with microarray analysis. The emergence of cortical cell type specific biomarkers will not only help neuropathological diagnosis, but will also eventually reveal the causal relations in the pathogenesis of various cortical developmental disorders.


Asunto(s)
Corteza Cerebral/embriología , Genes del Desarrollo/fisiología , Red Nerviosa/embriología , Animales , Axones/fisiología , Diferenciación Celular , Corteza Cerebral/metabolismo , Embrión de Mamíferos , Humanos , Modelos Biológicos , Red Nerviosa/metabolismo , Neuronas/fisiología , Factores de Tiempo
12.
J Neurosci ; 25(30): 7004-13, 2005 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-16049176

RESUMEN

The myelin basic protein (MBP) gene encodes two families of proteins, the classic MBP constituents of myelin and the golli-MBPs, the function of which is less well understood. In this study, targeted ablation of the golli-MBPs, but not the classic MBPs, resulted in a distinct phenotype unlike that of knock-outs (KOs) of the classic MBPs or other myelin proteins. Although the golli KO animals did not display an overt dysmyelinating phenotype, they did exhibit delayed and/or hypomyelination in selected areas of the brain, such as the visual cortex and the optic nerve, as determined by Northern and Western blots and immunohistochemical analysis with myelin protein markers. Hypomyelination in some areas, such as the visual cortex, persisted into adulthood. Ultrastructural analysis of the KOs confirmed both the delay and hypomyelination and revealed abnormalities in myelin structure and in some oligodendrocytes. Abnormal visual-evoked potentials indicated that the hypomyelination in the visual cortex had functional consequences in the golli KO brain. Evidence that the abnormal myelination in these animals was a consequence of intrinsic problems with the oligodendrocyte was indicated by an impaired ability of oligodendrocytes to form myelin sheets in culture and by the presence of abnormal Ca2+ transients in purified cortical oligodendrocytes studied in vitro. The Ca2+ results reported in this study complement previous results implicating golli proteins in modulating intracellular signaling in T-cells. Together, all these findings suggest a role for golli proteins in oligodendrocyte differentiation, migration, and/or myelin elaboration in the brain.


Asunto(s)
Vaina de Mielina/patología , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/fisiología , Oligodendroglía/patología , Nervio Óptico/patología , Factores de Transcripción/genética , Factores de Transcripción/fisiología , Corteza Visual/patología , Animales , Calcio/metabolismo , Femenino , Homeostasis , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Microscopía Electrónica , Proteína Básica de Mielina , Fibras Nerviosas Mielínicas/patología , Fibras Nerviosas Mielínicas/ultraestructura , Oligodendroglía/metabolismo
14.
Neurochem Res ; 29(5): 997-1002, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15139298

RESUMEN

In addition to classic proteolipid protein (PLP) and DM20, the mouse myelin proteolipid gene produces the sr-PLP and sr-DM20 proteins. The sr-isoforms are localized to the cell bodies of both oligodendrocytes and neurons. However, they are expressed to a greater extent in neurons than they are in glia. In this study, we examined expression of the sr-proteolipids in the mouse embryo using immunohistochemistry with an sr-PLP/DM20 specific antibody. Widespread expression of the sr-proteins was found in many nonmyelinating cell types. In particular, strong immunoreactivity was detected in motor neurons of both the autonomic and somatic nervous systems as well as in striated muscle. This pattern of expression persisted throughout the embryonic period studied. Thus, the sr-proteolipids are expressed prior to the onset of myelination and in a much broader array of cell types than their classic counterparts. These results support the conclusion that the sr-isoforms of the PLP gene have a biological role independent of myelination.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica , Neuronas Motoras/metabolismo , Músculos/metabolismo , Proteína Proteolipídica de la Mielina/genética , Animales , Inmunohistoquímica , Ratones , Músculos/embriología
15.
Dev Neurosci ; 25(2-4): 96-104, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12966208

RESUMEN

The myelin proteolipid gene encodes two sets of proteins, the classic PLP and DM20 and the sr (soma-restricted)-PLP and sr-DM20. Unlike the classic proteolipids, the sr-products are expressed in both neurons and oligodendrocytes (OLs) and are not components of the myelin sheath. In OLs, the sr-isoforms are associated with endosomes and recycling vesicles indicating a possible nonmyelin function for these proteins. In this study, a purified antibody specific for the sr-products was used to examine the expression of these proteins during the development of the mouse brain. We found that while sr-PLP and sr-DM20 are expressed in OLs, the highest levels of immunoreactivity were found in neuronal populations. During early embryonic development (E13-E15), sr-proteolipids were detected in the dorsal root ganglion and motor neurons in the spinal cord. By E17, immunostaining for sr-PLP and sr-DM20 in the brain increased dramatically. The highest levels of immunoreactivity were found during the first and second weeks postnatal after which staining intensity declined to adult levels and the pattern of expression was more restricted. Robust staining persisted in many neuronal populations including nuclei in the hindbrain, Purkinje and granule neurons in the cerebellum, pyramidal cells in the cortex and mitral cells in the olfactory bulb. The spatial and temporal pattern of sr-PLP and sr-DM20 expression is very similar to that of the endosomal protein, syntaxin 13, consistent with the finding that the sr-PLPs may play a role in vesicular transport in neurons.


Asunto(s)
Desarrollo Embrionario y Fetal/genética , Regulación del Desarrollo de la Expresión Génica , Proteína Proteolipídica de la Mielina/biosíntesis , Proteína Proteolipídica de la Mielina/genética , Neuronas/citología , Animales , Encéfalo/embriología , Embrión de Mamíferos , Femenino , Ganglios Espinales/embriología , Inmunohistoquímica , Ratones , Oligodendroglía/citología , Embarazo , Isoformas de Proteínas/biosíntesis , Isoformas de Proteínas/genética , Médula Espinal/embriología
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