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1.
J Oral Maxillofac Surg ; 82(6): 632-640, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38442876

RESUMO

This technical innovation demonstrates the use of ImmersiveTouch Virtual Reality (VR) and Augmented Reality (AR)-guided total temporomandibular joint replacement (TJR) using Biomet stock prosthesis in 2 patients with condylar degeneration. TJR VR planning includes condylar resection, prosthesis selection and positioning, and interference identification. AR provides real-time guidance for osteotomies, placement of prostheses and fixation screws, occlusion verification, and flexibility to modify the surgical course. Radiographic analysis demonstrated high correspondence between the preoperative plan and postoperative result. The average differences in the positioning of the condylar and fossa prosthesis are 1.252 ± 0.269 mm and 1.393 ± 0.335 mm, respectively. The main challenges include a steep learning curve, intraoperative technical difficulties, added surgical time, and additional costs. In conclusion, the case report demonstrates the advantages of implementing AR and VR technology in TJR's using stock prostheses as a pilot study. Further clinical trials are needed prior to this innovation becoming a mainstream practice.


Assuntos
Artroplastia de Substituição , Realidade Aumentada , Prótese Articular , Transtornos da Articulação Temporomandibular , Realidade Virtual , Humanos , Artroplastia de Substituição/métodos , Artroplastia de Substituição/instrumentação , Transtornos da Articulação Temporomandibular/cirurgia , Côndilo Mandibular/cirurgia , Côndilo Mandibular/diagnóstico por imagem , Cirurgia Assistida por Computador/métodos , Feminino , Desenho de Prótese , Pessoa de Meia-Idade , Masculino , Articulação Temporomandibular/cirurgia , Articulação Temporomandibular/diagnóstico por imagem , Imageamento Tridimensional
2.
Nature ; 546(7657): 297-301, 2017 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-28562592

RESUMO

Adult pair bonding involves dramatic changes in the perception and valuation of another individual. One key change is that partners come to reliably activate the brain's reward system, although the precise neural mechanisms by which partners become rewarding during sociosexual interactions leading to a bond remain unclear. Here we show, using a prairie vole (Microtus ochrogaster) model of social bonding, how a functional circuit from the medial prefrontal cortex to nucleus accumbens is dynamically modulated to enhance females' affiliative behaviour towards a partner. Individual variation in the strength of this functional connectivity, particularly after the first mating encounter, predicts how quickly animals begin affiliative huddling with their partner. Rhythmically activating this circuit in a social context without mating biases later preference towards a partner, indicating that this circuit's activity is not just correlated with how quickly animals become affiliative but causally accelerates it. These results provide the first dynamic view of corticostriatal activity during bond formation, revealing how social interactions can recruit brain reward systems to drive changes in affiliative behaviour.


Assuntos
Arvicolinae/fisiologia , Arvicolinae/psicologia , Núcleo Accumbens/fisiologia , Ligação do Par , Córtex Pré-Frontal/fisiologia , Recompensa , Comportamento Social , Animais , Feminino , Masculino , Preferência de Acasalamento Animal/fisiologia , Núcleo Accumbens/citologia , Córtex Pré-Frontal/citologia , Fatores de Tempo
3.
Neural Plast ; 2023: 5225952, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36845359

RESUMO

While infant cues are often assumed to innately motivate maternal response, recent research highlights how the neural coding of infant cues is altered through maternal care. Infant vocalizations are important social signals for caregivers, and evidence from mice suggests that experience caring for mouse pups induces inhibitory plasticity in the auditory cortex (AC), though the molecular mediators for such AC plasticity during the initial pup experience are not well delineated. Here, we used the maternal mouse communication model to explore whether transcription in AC of a specific, inhibition-linked, memory-associated gene, brain-derived neurotrophic factor (Bdnf) changes due to the very first pup caring experience hearing vocalizations, while controlling for the systemic influence of the hormone estrogen. Ovariectomized and estradiol or blank-implanted virgin female mice hearing pup calls with pups present had significantly higher AC exon IV Bdnf mRNA compared to females without pups present, suggesting that the social context of vocalizations induces immediate molecular changes at the site of auditory cortical processing. E2 influenced the rate of maternal behavior but did not significantly affect Bdnf mRNA transcription in the AC. To our knowledge, this is the first time Bdnf has been associated with processing social vocalizations in the AC, and our results suggest that it is a potential molecular component responsible for enhancing future recognition of infant cues by contributing to AC plasticity.


Assuntos
Córtex Auditivo , Animais , Feminino , Camundongos , Humanos , Córtex Auditivo/fisiologia , Animais Recém-Nascidos , Vocalização Animal/fisiologia , Fator Neurotrófico Derivado do Encéfalo/genética , Estimulação Acústica/métodos , Audição , Comportamento Materno/fisiologia , RNA Mensageiro
4.
J Infect Dis ; 225(1): 55-64, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34139752

RESUMO

BACKGROUND: Although a human adenovirus (HAdV) vaccine is available for military use, officers-in-training are not routinely vaccinated. We describe an HAdV-associated respiratory outbreak among unvaccinated cadets at the US Coast Guard Academy and its impact on cadet training. METHODS: We defined a case as a cadet with new onset cough or sore throat during August 1-October 4, 2019. We reviewed medical records and distributed a questionnaire to identify cases and to estimate impact on cadet training. We performed real-time polymerase chain reaction testing on patient and environmental samples and whole genome sequencing on a subset of positive patient samples. RESULTS: Among the 1072 cadets, 378 (35%) cases were identified by medical records (n = 230) or additionally by the questionnaire (n = 148). Of the 230 cases identified from medical records, 138 (60%) were male and 226 (98%) had no underlying conditions. From questionnaire responses, 113 of 228 (50%) cases reported duty restrictions. Of cases with respiratory specimens, 36 of 50 (72%) were HAdV positive; all 14 sequenced specimens were HAdV-4a1. Sixteen (89%) of 18 environmental specimens from the cadet dormitory were HAdV-positive. CONCLUSIONS: The HAdV-4-associated outbreak infected a substantial number of cadets and significantly impacted cadet training. Routine vaccination could prevent HAdV respiratory outbreaks in this population.


Assuntos
Infecções por Adenovirus Humanos/epidemiologia , Vacinas contra Adenovirus , Adenovírus Humanos/isolamento & purificação , Militares/estatística & dados numéricos , Reação em Cadeia da Polimerase/métodos , Infecções Respiratórias/epidemiologia , Adenovírus Humanos/genética , Adolescente , Surtos de Doenças , Feminino , Humanos , Masculino , Infecções Respiratórias/virologia , Estados Unidos/epidemiologia , Adulto Jovem
5.
Gen Comp Endocrinol ; 328: 114102, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35944650

RESUMO

Thyroid hormone (T3) is important for adult organ function and vertebrate development, particularly during the postembryonic period when many organs develop/mature into their adult forms. Amphibian metamorphosis is totally dependent on T3 and can be easily manipulated, thus offering a unique opportunity for studying how T3 controls postembryonic development in vertebrates. Numerous early studies have demonstrated that T3 affects frog metamorphosis through T3 receptor (TR)-mediated regulation of T3 response genes, where TR forms a heterodimer with RXR (9-cis retinoic acid receptor) and binds to T3 response elements (TREs) in T3 response genes to regulate their expression. We have previously identified many candidate direct T3 response genes in Xenopus tropicalis tadpole intestine. Among them is the proto-oncogene Ski, which encodes a nuclear protein with complex function in regulating cell fate. We show here that Ski is upregulated in the intestine and tail of premetamorphic tadpoles upon T3 treatment and its expression peaks at stage 62, the climax of metamorphosis. We have further discovered a putative TRE in the first exon that can bind to TR/RXR in vitro and mediate T3 regulation of the promoter in vivo. These data demonstrate that Ski is activated by T3 through TR binding to a TRE in the first exon during Xenopus tropicalis metamorphosis, implicating a role of Ski in regulating cell fate during metamorphosis.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Metamorfose Biológica , Animais , Intestinos , Larva/metabolismo , Metamorfose Biológica/genética , Proteínas Nucleares/metabolismo , Proto-Oncogenes , Receptores dos Hormônios Tireóideos/genética , Receptores dos Hormônios Tireóideos/metabolismo , Receptores X de Retinoides/genética , Receptores X de Retinoides/metabolismo , Hormônios Tireóideos , Tri-Iodotironina/metabolismo , Tri-Iodotironina/farmacologia , Regulação para Cima , Xenopus/genética , Xenopus laevis/metabolismo
6.
J Neurosci ; 40(23): 4469-4482, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32327533

RESUMO

Time-dependent frequency trajectories are an inherent feature of many behaviorally relevant sounds, such as species-specific vocalizations. Dynamic frequency trajectories, even in short sounds, often convey meaningful information, which may be used to differentiate sound categories. However, it is not clear what and where neural responses in the auditory cortical pathway are critical for conveying information about behaviorally relevant frequency trajectories, and how these responses change with experience. Here, we uncover tuning to subtle variations in frequency trajectories in auditory cortex of female mice. We found that auditory cortical responses could be modulated by variations in a pure tone trajectory as small as 1/24th of an octave, comparable to what has been reported in primates. In particular, late spiking after the end of a sound stimulus was more often sensitive to the sound's subtle frequency variation compared with spiking during the sound. Such "Off" responses in the adult A2, but not those in core auditory cortex, were plastic in a way that may enhance the representation of a newly acquired, behaviorally relevant sound category. We illustrate this with the maternal mouse paradigm for natural vocalization learning. By using an ethologically inspired paradigm to drive auditory responses in higher-order neurons, our results demonstrate that mouse auditory cortex can track fine frequency changes, which allows A2 Off responses in particular to better respond to pitch trajectories that distinguish behaviorally relevant, natural sound categories.SIGNIFICANCE STATEMENT A whistle's pitch conveys meaning to its listener, as when dogs learn that distinct pitch trajectories whistled by their owner differentiate specific commands. Many species use pitch trajectories in their own vocalizations to distinguish sound categories, such as in human languages, such as Mandarin. How and where auditory neural activity encodes these pitch trajectories as their meaning is learned but not well understood, especially for short-duration sounds. We studied this in mice, where infants use ultrasonic whistles to communicate to adults. We found that late neural firing after a sound ends can be tuned to how the pitch changes in time, and that this response in a secondary auditory cortical field changes with experience to acquire a pitch change's meaning.


Assuntos
Estimulação Acústica/métodos , Potenciais de Ação/fisiologia , Córtex Auditivo/fisiologia , Percepção da Altura Sonora/fisiologia , Tempo de Reação/fisiologia , Fatores Etários , Animais , Eletrodos Implantados , Feminino , Camundongos , Camundongos Endogâmicos CBA , Distribuição Aleatória
7.
Development ; 145(8)2018 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-29615464

RESUMO

Embryonic morphogenesis of a complex organism requires proper regulation of patterning and directional growth. Planar cell polarity (PCP) signaling is emerging as a crucial evolutionarily conserved mechanism whereby directional information is conveyed. PCP is thought to be established by global cues, and recent studies have revealed an instructive role of a Wnt signaling gradient in epithelial tissues of both invertebrates and vertebrates. However, it remains unclear whether Wnt/PCP signaling is regulated in a coordinated manner with embryonic patterning during morphogenesis. Here, in mouse developing limbs, we find that apical ectoderm ridge-derived Fgfs required for limb patterning regulate PCP along the proximal-distal axis in a Wnt5a-dependent manner. We demonstrate with genetic evidence that the Wnt5a gradient acts as a global cue that is instructive in establishing PCP in the limb mesenchyme, and that Wnt5a also plays a permissive role to allow Fgf signaling to orient PCP. Our results indicate that limb morphogenesis is regulated by coordination of directional growth and patterning through integration of Wnt5a and Fgf signaling.


Assuntos
Padronização Corporal/fisiologia , Polaridade Celular/fisiologia , Fator 4 de Crescimento de Fibroblastos/fisiologia , Fator 8 de Crescimento de Fibroblasto/fisiologia , Proteína Wnt-5a/fisiologia , Animais , Padronização Corporal/genética , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Extremidades/embriologia , Fator 4 de Crescimento de Fibroblastos/deficiência , Fator 4 de Crescimento de Fibroblastos/genética , Fator 8 de Crescimento de Fibroblasto/deficiência , Fator 8 de Crescimento de Fibroblasto/genética , Mesoderma/embriologia , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Transdução de Sinais , Proteína Wnt-5a/deficiência , Proteína Wnt-5a/genética
8.
Horm Behav ; 124: 104779, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32502487

RESUMO

While mothering is often instinctive and stereotyped in species-specific ways, evolution can favor genetically "open" behavior programs that allow experience to shape infant care. Among experience-dependent maternal behavioral mechanisms, sensory learning about infants has been hard to separate from motivational changes arising from sensitization with infants. We developed a paradigm in which sensory learning of an infant-associated cue improves a stereotypical maternal behavior in female mice. Mice instinctively employed a spatial memory-based strategy when engaged repetitively in a pup search and retrieval task. However, by playing a sound from a T-maze arm to signal where a pup will be delivered for retrieval, mice learned within 7 days and retained for at least 2 weeks the ability to use this specific cue to guide a more efficient search strategy. The motivation to retrieve pups also increased with learning on average, but their correlation did not explain performance at the trial level. Bilaterally silencing auditory cortical activity significantly impaired the utilization of new strategy without changing the motivation to retrieve pups. Finally, motherhood as compared to infant-care experience alone accelerated how quickly the new sensory-based strategy was acquired, suggesting a role for the maternal hormonal state. By rigorously establishing that newly formed sensory associations can improve the performance of a natural maternal behavior, this work facilitates future studies into the neurochemical and circuit mechanisms that mediate novel sensory learning in the maternal context, as well as more learning-based mechanisms of parental behavior in rodents.


Assuntos
Aprendizagem/fisiologia , Comportamento Materno/fisiologia , Comportamento Estereotipado/fisiologia , Estimulação Acústica , Animais , Animais Recém-Nascidos , Córtex Auditivo/fisiologia , Comportamento Animal/fisiologia , Condicionamento Operante/fisiologia , Feminino , Humanos , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos CBA , Motivação , Plasticidade Neuronal/fisiologia , Comportamento Social , Localização de Som/fisiologia , Vocalização Animal/fisiologia
9.
Prehosp Emerg Care ; 24(6): 733-740, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31971839

RESUMO

Objective: Many sepsis patients receive initial care from prehospital Emergency Medical Services (EMS). While earlier sepsis care improves outcomes, the characteristics, care and outcomes of those treated by EMS versus those arriving directly to an emergency department (ED) are currently not detailed. We sought to determine differences in hospital presentation, course and outcomes between EMS and non-EMS patients enrolled in the Protocolized Care of Early Septic Shock (ProCESS) trial. Methods: We performed a secondary analysis of ProCESS, which studied ED patients with septic shock. EMS care was the primary exposure. We determined differences in demographics, clinical features, interventions and hospital course between EMS and non-EMS patients. Using mixed models, we determined the association between EMS care and 60-day mortality. Results: Among 1,341 patients, 826 (61.6%) received initial EMS care. EMS patients were older, more likely to be black (OR 1.49, 95% CI 1.14-1.95) or nursing home residents (5.57, 3.61-8.60), and more likely to have chronic respiratory disease (1.36, 1.04-1.78), cerebral vascular disease (1.56; 1.04-2.33), peripheral vascular disease (2.02; 1.29-3.16), and dementia (3.53; 2.04-6.10). EMS patients were more likely to present with coma (4.48; 2.53-7.96) or elevated lactate (1.30; 1.04-1.63), and to receive mechanical ventilation in the ED (7.16; 4.34-11.79). There were no differences in infection source or total intravenous fluids. Initial differences in vasopressor use (1.66; 1.22-2.26) resolved at 6 hours (1.18; 0.94-1.47). Initial differences in APACHE II (EMS 21.8 vs. non-EMS 19.0) narrowed by 48 hours (17.9 vs. 16.3, [EMS X time] interaction p = 0.003). Although EMS patients exhibited higher 60-day mortality, after adjustment for confounders, this association was not significant (1.09, 95% CI: 0.78-1.55). Conclusions: While EMS sepsis patients presented with worse chronic, nonmodifiable characteristics and higher acuity than non-EMS patients, differences in acuity narrowed after initial hospital care. Despite having higher illness burden, EMS patients did not have worse adjusted short-term mortality.


Assuntos
Serviços Médicos de Emergência , Sepse , Idoso , Comorbidade , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sepse/mortalidade , Sepse/terapia
10.
Water Sci Technol ; 79(4): 789-797, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30975945

RESUMO

This study recycles titanium dioxide (TiO2) that is contained in waste selective non-catalytic reduction (SNCR) catalysts using acid or alkali. The waste SNCR is then filtered, baked, ground and calcined to form a photo-catalytic powder. The nano-TiO2 photo-catalysts that are obtained using both processes are then tested and compared. The two TiO2 photo-catalysts that are produced from waste SNCR catalysts have a diameter of 30-40 nm. Energy dispersive spectrometry (EDS) and inductively coupled plasma (ICP) are used to determine the elemental composition of TiO2 and X-ray diffraction (XRD) is used to determine the crystalline phase. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) are used to determine the surface morphology, the structure and the particle size. The effect of placing porous TiO2 in a suspension is also determined. This study demonstrates the production of a photo-catalyst from an SNCR catalyst and its effect in advanced oxidation processes (AOP). When everdirect supra turquoise blue (FBL) dye wastewater is degraded in the presence of ultraviolet (UV) /TiO2, more than 90% of the total oxidizable carbon (TOC) is removed.


Assuntos
Corantes/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Catálise , Microscopia Eletrônica de Transmissão , Oxirredução , Tamanho da Partícula , Titânio/química , Poluentes Químicos da Água/análise , Difração de Raios X
11.
Learn Mem ; 24(12): 612-621, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29142056

RESUMO

Learning to recognize a stimulus category requires experience with its many natural variations. However, the mechanisms that allow a category's sensorineural representation to be updated after experiencing new exemplars are not well understood, particularly at the molecular level. Here we investigate how a natural vocal category induces expression in the auditory system of a key synaptic plasticity effector immediate early gene, Arc/Arg3.1, which is required for memory consolidation. We use the ultrasonic communication system between mouse pups and adult females to study whether prior familiarity with pup vocalizations alters how Arc is engaged in the core auditory cortex after playback of novel exemplars from the pup vocal category. A computerized, 3D surface-assisted cellular compartmental analysis, validated against manual cell counts, demonstrates significant changes in the recruitment of neurons expressing Arc in pup-experienced animals (mothers and virgin females "cocaring" for pups) compared with pup-inexperienced animals (pup-naïve virgins), especially when listening to more familiar, natural calls compared to less familiar but similarly recognized tonal model calls. Our data support the hypothesis that the kinetics of Arc induction to refine cortical representations of sensory categories is sensitive to the familiarity of the sensory experience.


Assuntos
Córtex Auditivo/metabolismo , Percepção Auditiva/fisiologia , Proteínas do Citoesqueleto/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Reconhecimento Psicológico/fisiologia , Vocalização Animal/fisiologia , Estimulação Acústica , Análise de Variância , Animais , Animais Recém-Nascidos , Córtex Auditivo/citologia , Proteínas do Citoesqueleto/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Masculino , Camundongos , Proteínas do Tecido Nervoso/genética , Neurônios/classificação , Neurônios/metabolismo , RNA Mensageiro/metabolismo , Fatores de Tempo , Ondas Ultrassônicas
12.
J Neurosci ; 35(6): 2432-7, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25673838

RESUMO

Critical periods are developmental windows during which the stimuli an animal encounters can reshape response properties in the affected system to a profound degree. Despite this window's importance, the neural mechanisms that regulate it are not completely understood. Pioneering studies in visual cortex initially indicated that norepinephrine (NE) permits ocular dominance column plasticity during the critical period, but later research has suggested otherwise. More recent work implicating NE in experience-dependent plasticity in the adult auditory cortex led us to re-examine the role of NE in critical period plasticity. Here, we exposed dopamine ß-hydroxylase knock-out (Dbh(-/-)) mice, which lack NE completely from birth, to a biased acoustic environment during the auditory cortical critical period. This manipulation led to a redistribution of best frequencies (BFs) across auditory cortex in our control mice, consistent with prior work. By contrast, Dbh(-/-) mice failed to exhibit the expected redistribution of BFs, even though NE-deficient and NE-competent mice showed comparable auditory cortical organization when reared in a quiet colony environment. These data suggest that while intrinsic tonotopic patterning of auditory cortical circuitry occurs independently from NE, NE is required for critical period plasticity in auditory cortex.


Assuntos
Córtex Auditivo/crescimento & desenvolvimento , Córtex Auditivo/fisiologia , Aprendizagem/fisiologia , Plasticidade Neuronal/fisiologia , Norepinefrina/fisiologia , Estimulação Acústica , Animais , Limiar Auditivo/fisiologia , Mapeamento Encefálico , Período Crítico Psicológico , Dopamina beta-Hidroxilase/genética , Dopamina beta-Hidroxilase/metabolismo , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Percepção da Altura Sonora/fisiologia
13.
J Neurosci ; 35(6): 2636-45, 2015 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-25673855

RESUMO

Sound categorization is essential for auditory behaviors like acoustic communication, but its genesis within the auditory pathway is not well understood-especially for learned natural categories like vocalizations, which often share overlapping acoustic features that must be distinguished (e.g., speech). We use electrophysiological mapping and single-unit recordings in mice to investigate how representations of natural vocal categories within core auditory cortex are modulated when one category acquires enhanced behavioral relevance. Taking advantage of a maternal mouse model of acoustic communication, we found no long-term auditory cortical map expansion to represent a behaviorally relevant pup vocalization category-contrary to expectations from the cortical plasticity literature on conditioning with pure tones. Instead, we observed plasticity that improved the separation between acoustically similar pup and adult vocalization categories among a physiologically defined subset of late-onset, putative pyramidal neurons, but not among putative interneurons. Additionally, a larger proportion of these putative pyramidal neurons in maternal animals compared with nonmaternal animals responded to the individual pup call exemplars having combinations of acoustic features most typical of that category. Together, these data suggest that higher-order representations of acoustic categories arise from a subset of core auditory cortical pyramidal neurons that become biased toward the combination of acoustic features statistically predictive of membership to a behaviorally relevant sound category.


Assuntos
Córtex Auditivo/fisiologia , Comportamento Animal/fisiologia , Células Piramidais/fisiologia , Vocalização Animal/fisiologia , Estimulação Acústica , Animais , Córtex Auditivo/citologia , Feminino , Audição/fisiologia , Camundongos , Camundongos Endogâmicos CBA , Plasticidade Neuronal/fisiologia , Razão Sinal-Ruído , Ultrassom
15.
J Biol Chem ; 289(14): 9547-59, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24554698

RESUMO

Fluid shear stresses are potent regulators of vascular homeostasis and powerful determinants of vascular disease progression. The glycocalyx is a layer of glycoaminoglycans, proteoglycans, and glycoproteins that lines the luminal surface of arteries. The glycocalyx interacts directly with hemodynamic forces from blood flow and, consequently, is a prime candidate for the mechanosensing of fluidic shear stresses. Here, we investigated the role of the glycocalyx component syndecan-1 (sdc-1) in controlling the shear stress-induced signaling and flow-mediated phenotypic modulation in endothelial cells. We found that knock-out of sdc-1 abolished several key early signaling events of endothelial cells in response to shear stress including the phosphorylation of Akt, the formation of a spatial gradient in paxillin phosphorylation, and the activation of RhoA. After exposure to atheroprotective flow, we found that sdc-1 knock-out endothelial cells had a phenotypic shift to an inflammatory/pro-atherosclerotic phenotype in contrast to the atheroprotective phenotype of wild type cells. Consistent with these findings, we found increased leukocyte adhesion to sdc-1 knock-out endothelial cells in vitro that was reduced by re-expression of sdc-1. In vivo, we found increased leukocyte recruitment and vascular permeability/inflammation in sdc-1 knock-out mice. Taken together, our studies support a key role for sdc-1 in endothelial mechanosensing and regulation of endothelial phenotype.


Assuntos
Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Glicocálix/metabolismo , Mecanotransdução Celular , Sindecana-1/metabolismo , Animais , Aterosclerose/genética , Aterosclerose/patologia , Velocidade do Fluxo Sanguíneo , Adesão Celular/genética , Linhagem Celular , Células Endoteliais/patologia , Glicocálix/genética , Glicocálix/patologia , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/patologia , Leucócitos/metabolismo , Leucócitos/patologia , Camundongos , Camundongos Knockout , Sindecana-1/genética
16.
J Cell Biochem ; 116(10): 2177-87, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25735755

RESUMO

Phagocytosis is critical to tissue homeostasis, as highlighted by phagocytosis defect of retinal pigment epithelial (RPE) cells with debris accumulation, photoreceptor degeneration and blindness. Phagocytosis ligands are the key to delineating molecular mechanisms and functional roles of phagocytes, but are traditionally identified in individual cases with technical challenges. We recently developed open reading frame phage display (OPD) for phagocytosis-based functional cloning (PFC) to identify unknown ligands. One of the identified ligands was Ly-1 antibody reactive clone (Lyar) with functions poorly defined. Herein, we characterized Lyar as a new ligand to stimulate RPE phagocytosis. In contrast to its reported nucleolar expression, immunohistochemistry showed that Lyar was highly expressed in photoreceptor outer segments (POSs) of the retina. Cytoplasmic Lyar was released from apoptotic cells, and selectively bound to shed POSs and apoptotic cells, but not healthy cells. POS vesicles engulfed through Lyar-dependent pathway were targeted to phagosomes and colocalized with phagosome marker Rab7. These results suggest that Lyar is a genuine RPE phagocytosis ligand, which in turn supports the validity of OPD/PFC as the only available approach for unbiased identification of phagocytosis ligands with broad applicability to various phagocytes.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas Nucleares/genética , Retina/metabolismo , Segmento Externo das Células Fotorreceptoras da Retina/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Animais , Apoptose/genética , Proteínas de Ligação a DNA/metabolismo , Ligantes , Camundongos , Proteínas Nucleares/metabolismo , Fagócitos/metabolismo , Fagocitose/genética , Retina/crescimento & desenvolvimento , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina/genética , Pigmentos da Retina/metabolismo , Proteínas rab de Ligação ao GTP/genética , proteínas de unión al GTP Rab7
17.
Mol Carcinog ; 54(11): 1503-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25154389

RESUMO

The level of 5-hydroxymethylcytosine (5-hmC) converted by ten-eleven translocation (TET) family is decreased in cancers. However, whether 5-hmC level is perturbed in early stages of carcinogenesis caused by genotoxic carcinogens is not defined. 5-hmC levels and TET2 expression were measured in liver of rats treated with genotoxic carcinogens, riddelliine, or aristolochic acid. Levels of 5-hmC and TET2 expression decreased in the liver of the carcinogens-treated rats. Loss of 5-hmC correlates well with documented induction of genetic mutations by the carcinogens, suggesting that TET2-mediated 5-hydroxymethylation plays an epigenetic role in early state of carcinogenesis.


Assuntos
Ácidos Aristolóquicos/toxicidade , Carcinógenos/toxicidade , Citosina/análogos & derivados , Fígado/metabolismo , Alcaloides de Pirrolizidina/toxicidade , 5-Metilcitosina/análogos & derivados , Animais , Carcinogênese/efeitos dos fármacos , Citosina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Epigênese Genética/efeitos dos fármacos , Mutação/efeitos dos fármacos , Neoplasias/induzido quimicamente , Neoplasias/metabolismo , Ratos , Ratos Endogâmicos F344 , Ratos Transgênicos
18.
Front Neuroendocrinol ; 34(4): 300-14, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23916405

RESUMO

Much of the literature on maternal behavior has focused on the role of infant experience and hormones in a canonical subcortical circuit for maternal motivation and maternal memory. Although early studies demonstrated that the cerebral cortex also plays a significant role in maternal behaviors, little has been done to explore what that role may be. Recent work though has provided evidence that the cortex, particularly sensory cortices, contains correlates of sensory memories of infant cues, consistent with classical studies of experience-dependent sensory cortical plasticity in non-maternal paradigms. By reviewing the literature from both the maternal behavior and sensory cortical plasticity fields, focusing on the auditory modality, we hypothesize that maternal hormones (predominantly estrogen) may act to prime auditory cortical neurons for a longer-lasting neural trace of infant vocal cues, thereby facilitating recognition and discrimination. This couldthen more efficiently activate the subcortical circuit to elicit and sustain maternal behavior.


Assuntos
Estrogênios/metabolismo , Aprendizagem/fisiologia , Memória/fisiologia , Relações Mãe-Filho , Plasticidade Neuronal/fisiologia , Animais , Sinais (Psicologia) , Humanos , Lactente
19.
bioRxiv ; 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37745495

RESUMO

In ethological behaviors like parenting, animals innately follow stereotyped patterns of choices to decide between uncertain outcomes but can learn to modify their strategies to incorporate new information. For example, female mice in a T-maze instinctively use spatial-memory to search for pups where they last found them but can learn more efficient strategies employing pup-associated acoustic cues. We uncovered neural correlates for transitioning between these innate and learned strategies. Auditory cortex (ACx) was required during learning. ACx firing at the nest increased with learning and correlated with subsequent search speed but not outcome. Surprisingly, ACx suppression rather than facilitation during search was more prognostic of correct sound-cued outcomes - even before adopting a sound-cued strategy. Meanwhile medial prefrontal cortex encoded the last pup location, but this decayed as the spatial-memory strategy declined. Our results suggest a neural competition between a weakening spatial-memory and strengthening sound-cued neural representation to mediate strategy switches.

20.
PNAS Nexus ; 2(4): pgad085, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37113978

RESUMO

Neurodevelopmental disorders (NDDs) are a widespread and growing public health challenge, affecting as many as 17% of children in the United States. Recent epidemiological studies have implicated ambient exposure to pyrethroid pesticides during pregnancy in the risk for NDDs in the unborn child. Using a litter-based, independent discovery-replication cohort design, we exposed mouse dams orally during pregnancy and lactation to the Environmental Protection Agency's reference pyrethroid, deltamethrin, at 3 mg/kg, a concentration well below the benchmark dose used for regulatory guidance. The resulting offspring were tested using behavioral and molecular methods targeting behavioral phenotypes relevant to autism and NDD, as well as changes to the striatal dopamine system. Low-dose developmental exposure to the pyrethroid deltamethrin (DPE) decreased pup vocalizations, increased repetitive behaviors, and impaired both fear conditioning and operant conditioning. Compared with control mice, DPE mice had greater total striatal dopamine, dopamine metabolites, and stimulated dopamine release, but no difference in vesicular dopamine capacity or protein markers of dopamine vesicles. Dopamine transporter protein levels were increased in DPE mice, but not temporal dopamine reuptake. Striatal medium spiny neurons showed changes in electrophysiological properties consistent with a compensatory decrease in neuronal excitability. Combined with previous findings, these results implicate DPE as a direct cause of an NDD-relevant behavioral phenotype and striatal dopamine dysfunction in mice and implicate the cytosolic compartment as the location of excess striatal dopamine.

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