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1.
J Endovasc Ther ; : 15266028241240900, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38533777

RESUMO

PURPOSE: Endovascular repair of chronic post-dissection thoraco-abdominal aortic aneurysms (PD-TAAA) presents specific technical challenges due to the presence of chronic septum. Small true lumen diameter and false lumen visceral vessel origin can make branched endograft prohibitive. Septotomy may allow to overcome these challenges in cases of high complex anatomy. TECHNIQUE: We describe the application of electrocautery septotomy to the visceral aorta segment to deploy an off-the-shelf branched endograft in a chronic PD-TAAA rupture with true lumen collapse. CONCLUSIONS: Electrocautery septotomy can be an effective adjunctive technique to facilitate branched endograft, overcoming technical challenges associated with the endovascular treatment of chronic PD-TAAA. CLINICAL IMPACT: Electrocautery septotomy is an adjunctive technique that can facilitate endovascular treatment of post-dissection thoraco-abdominal aneurysm. By creating a common lumen, this technique might reduce the number of re-interventions associated with PD-TAAA endovascular exclusion.

2.
Nat Neurosci ; 27(3): 497-513, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272967

RESUMO

Evidence of direct reciprocal connections between the cerebellum and basal ganglia has challenged the long-held notion that these structures function independently. While anatomical studies have suggested the presence of cerebellar projections to the substantia nigra pars compacta (SNc), the nature and function of these connections (Cb-SNc) is unknown. Here we show, in mice, that Cb-SNc projections form monosynaptic glutamatergic synapses with dopaminergic and non-dopaminergic neurons in the SNc. Optogenetic activation of Cb-SNc axons in the SNc is associated with increased SNc activity, elevated striatal dopamine levels and increased locomotion. During behavior, Cb-SNc projections are bilaterally activated before ambulation and unilateral lever manipulation. Cb-SNc projections show prominent activation for water reward and higher activation for sweet water, suggesting that the pathway also encodes reward value. Thus, the cerebellum directly, rapidly and effectively modulates basal ganglia dopamine levels and conveys information related to movement initiation, vigor and reward processing.


Assuntos
Dopamina , Substância Negra , Camundongos , Animais , Dopamina/metabolismo , Substância Negra/fisiologia , Locomoção , Cerebelo , Água/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-38044706

RESUMO

The production of sugarcane bioethanol generates large volumes of vinasse, an effluent whose final disposal can produce an environmental impact that is of concern. The long-term disposal of vinasse in sugarcane fields could challenge crop management, such as the performance of traditional herbicides, by changing soil properties. This study aimed to evaluate the effect of long-term vinasse application on the field and the dissipation of atrazine and ametryn herbicides in a subtropical sugarcane agroecosystem, and to discuss the potential processes involved in it. Vinasse affected soil properties by increasing pH (12%), electrical conductivity (160%), and soil organic carbon (25%) at 0-10 cm depth of soil. Differences in the herbicide calculated sorption coefficient (Kd) varied according to the pedotransfer function applied and the herbicide type (atrazine or ametryn). During the first seven days after herbicide application, the soil underwent long-term vinasse application and increased atrazine and ametryn dissipation 45% and 33%, respectively, compared with the conventional fertilization scheme (control). The Pesticide Root Zone Model revealed that dissipation was mediated mainly by the degradation process rather than transport or other processes. The long-term application of vinasse in a typical sugarcane field of Tucumán, Argentina decreased the potential groundwater pollution of triazines and, adversely, reduced their bioavailability for weed control. For this, the present study presents original information about how long-term treatment with vinasse may require an adaptation of conventional management practices such as the application of herbicides in Argentina and other sugarcane-producing regions. Integr Environ Assess Manag 2023;00:1-12. © 2023 SETAC.

4.
Endosc Int Open ; 11(9): E893-E898, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37810900

RESUMO

Background and study aims As life expectancy increases worldwide, so does the prevalence of biliary tract and pancreatic disorders, resulting in rising demand for invasive procedures such as endoscopic retrograde cholangiopancreatography (ERCP) in the elderly. Few studies have assessed the safety of ERCP in patients 90 years and older, particularly among the Hispanic population. The primary aim of this study was to determine the technical success and adverse events (AEs) associated with ERCP in patients 90 years of age or older in comparison to a younger cohort of patients. Patients and methods A retrospective analysis of all ERCPs done at our institution from 2012 to 2018 was performed. Three hundred ERCPs in patients < 90 years old and all 28 ERCPs done in patients ≥ 90 years old were included in the analysis. Results ERCPs were successfully completed in 96.4% of patients > 90 years old and 96.3% of the < 90-year-old cohort (realtive risk [RR] 1.00, confidence interval 0.92-1.07). There was no difference in the rate of periprocedural AEs. Post-ERCP AEs occurred in 7.1% and 3.0% in patients aged < 90 and > 90 years, respectively (RR 2.38, 0.54-10.48). No deaths were directly attributed to the procedure; however, inpatient mortality was higher in the group aged > 90 years. Conclusions ERCP is safe and effective in nonagenarian patients, and advanced age should not be considered an independent risk factor for AEs nor a contraindication for the procedure.

5.
Restor Dent Endod ; 48(3): e29, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37675446

RESUMO

Objectives: This study tested the hypothesis that cryotherapy duration influences lipopolysaccharide (LPS)-induced inflammation in a rat model. Materials and Methods: Six Wistar rats (Rattus norvegicus albinus) were used. Five sites were selected per animal and divided into 5 groups: a negative control group (NC), 2 positive control groups (PC1 and PC2), and 2 experimental groups (E1 and E2). Cryotherapy was applied for 1 minute (E1) or 5 minutes (E2). An acute inflammatory response was induced in the PC and E groups via subcutaneous administration of 0.5 mL/kg. In the PC2 group, a catheter was inserted without additional treatment. For the E1 and E2 groups, 2.5°C saline solution was administered through the implanted catheters for 1 and 5 minutes, respectively. The rats were sacrificed, and samples were obtained and processed for histological analysis, specifically examining the presence of polymorphonuclear neutrophils and hemorrhage. The χ2 test was used to compare the presence of acute inflammation across groups. Dependent variables were compared using the linear-by-linear association test. Results: Inflammation and hemorrhage varied significantly among the groups (p = 0.001). A significantly higher degree of acute inflammation was detected (p = 0.0002) in the PC and E1 samples than in the E2 group, in which cryotherapy was administered for 5 minutes. The PC and E1 groups also exhibited significantly greater numbers of neutrophils (p = 0.007), which were essentially absent in both the NC and E2 groups. Conclusions: Cryotherapy administration for 5 minutes reduced the acute inflammation associated with LPS and catheter implantation.

6.
Cancer Cell ; 41(8): 1466-1479.e9, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37541243

RESUMO

Glioblastoma progression in its early stages remains poorly understood. Here, we transfer PDGFB and genetic barcodes in mouse brain to initiate gliomagenesis and enable direct tracing of glioblastoma evolution from its earliest possible stage. Unexpectedly, we observe a high incidence of clonal extinction events and progressive divergence in clonal sizes, even after the acquisition of malignant phenotype. Computational modeling suggests these dynamics result from clonal-based cell-cell competition. Through bulk and single-cell transcriptome analyses, coupled with lineage tracing, we reveal that Myc transcriptional targets have the strongest correlation with clonal size imbalances. Moreover, we show that the downregulation of Myc expression is sufficient to drive competitive dynamics in intracranially transplanted gliomas. Our findings provide insights into glioblastoma evolution that are inaccessible using conventional retrospective approaches, highlighting the potential of combining clonal tracing and transcriptomic analyses in this field.


Assuntos
Glioblastoma , Glioma , Camundongos , Animais , Glioblastoma/genética , Glioblastoma/patologia , Estudos Retrospectivos , Glioma/genética , Perfilação da Expressão Gênica , Fenótipo
7.
Con-ciencia (La Paz) ; 11(1)jun. 2023. tab
Artigo em Espanhol | LILACS | ID: biblio-1448045

RESUMO

Introducción: El eucalipto fue utilizado el 2020 para tratar síntomas del coronavirus, en un intento de comprender el comportamiento reactivo del componente principal el eucaliptol, y con la finalidad de disponer de información preliminar para estudios posteriores, es que se escogió a esta molécula en el presente estudio. Se realizó un estudio químico teórico computacional, se calcularon propiedades moleculares, valores de longitudes de enlace y ángulos, así como propiedades químicas y descriptores químicos de interés en estudios QSAR, de energías y de reactividad. Objetivo: Determinar las propiedades moleculares, y descriptores de reactividad del eucaliptol con el fin de comprender el comportamiento reactivo mediante la Teoría Funcional de la Densidad (DFT). Método: Este estudio computacional utilizo los métodos Hartree Fock y la Teoría Funcional de densidad DFT, las propiedades químicas y descriptores moleculares para el eucaliptol, simulado en condiciones de vacío y en medio etanólico, fueron comparadas con los datos de referencia del Banco de Datos Europeo. Los descriptores ADME se calcularon con la estructura optimizada, usando los servidores en línea SwissADME y ADMETlab. Resultados: En cuanto se refiere a las longitudes de enlace intramolecular se encontró que no hay diferencia estadística significativa entre las longitudes de enlace en los cuatro tratamientos cuánticos. En los orbitales frontera, un band gap de 8,1 eV entre los orbitales HOMO LUMO muestra que la molécula es muy estable, los orbitales HOMO-1 y LUMO+1 de 9,8eV indica que se necesitaría mucha energía para que ocurra una transición electrónica. Conclusión: La teoría DFT B3LYP/6-31G fue aplicada sobre la estructura del eucaliptol, se investigaron algunas propiedades geométricas, electrónicas, de reactividad química y descriptores ADME intentando comprender el comportamiento reactivo de esta molécula, la energía de los orbitales HOMO-LUMO mostraron que la molécula tiene estabilidad energética, y los descriptores ADME sugieren una buena absorción a través de las membranas, finalmente el eucaliptol no es mutagénico desde el punto de vista de la química teórica.


Introduction: Eucalyptol was used in 2020 to treat coronavirus symptoms, in an attempt to understand the reactive behavior of the eucalyptol, a main molecule, and in order to have preliminary information for subsequent studies, this molecule was chosen in this study. A computational theoretical chemical study was carried out, molecular properties, values ​​of bond lengths and angles, as well as chemical properties and chemical descriptors of interest in QSAR, energy and reactivity studies were calculated. Objective: To determine the molecular properties and reactivity descriptors of eucalyptol in order to understand the reactive behavior through the Density Functional Theory (DFT). Method: This computational study used the Hartree Fock methods and the DFT Density Functional Theory, the chemical properties and molecular descriptors for eucalyptol, simulated under vacuum conditions and in ethanolic medium, were compared with the reference data from the Data Bank. European. The ADME descriptors were calculated with the optimized structure, using the online servers SwissADME and ADMETlab. Results: Regarding the intramolecular bond lengths, it was found that there is no statistically significant difference between the bond lengths in the four quantum treatments. In the frontier orbitals, a band gap of 8.1 eV between the HOMO LUMO orbitals shows that the molecule is very stable, the HOMO-1 and LUMO+1 orbitals of 9.8eV indicate that a lot of energy would be needed for a transition to occur. electronics. Conclusion: The DFT B3LYP/6-31G theory was applied to the structure of eucalyptol, some geometric, electronic, chemical reactivity properties and ADME descriptors were investigated trying to understand the reactive behavior of this molecule, the energy of the HOMO-LUMO orbitals showed that the molecule has energetic stability, and the ADME descriptors suggest a good absorption through the membranes, finally eucalyptol is not mutagenic from the point of view of theoretical chemistry.

8.
J Endovasc Ther ; : 15266028231163067, 2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37029570

RESUMO

PURPOSE: The aim of our study is to investigate the feasibility of retrograde cannulation using devices with inner branches (IB) for the endovascular treatment of thoracoabdominal aortic aneurysms (TAAAs). MATERIALS AND METHODS: A retrospective analysis using IB configuration with retrograde cannulation was carried out on TAAAs patients undergoing endovascular treatment. RESULTS: Seven patients underwent IB endovascular treatment with retrograde cannulation between September 2020 and November 2021. The mean age was 80.4 years and 4 patients were male. A total of 26 of 28 target vessels were cannulated by retrograde access with a technical success of 93% (2 of 26 target vessels). Two intra-procedural complications were observed (1 renal artery dissection and 1 collateral renal artery rupture). In total, 26 of 28 treated vessels were retrograde cannulated with a technical success of 93%. A total of 39 stent bridges were used (all Viabahn VBX devices). The mean duration of the procedure was 321±102 minutes, and the mean scan time was 134±62 minutes. Mortality at 30 days was observed in 1 case. During the follow-up, 1 stent bridge occlusion was observed without the need for reintervention. CONCLUSION: Retrograde cannulation can also be successfully performed in the case of inner branches. CLINICAL IMPACT: In inner branched cases, retrograde cannulation should be taken into consideration in particular cases or it could become the option of choice. Dedicated endovascular material available such as steerable catheters and latest generation covered stents is fundamental for the success of the treatment.

9.
J Cardiovasc Surg (Torino) ; 64(2): 150-158, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36897208

RESUMO

BACKGROUND: The GORE EXCLUDER Conformable Endoprosthesis with active control (CEXC) was developed to treat challenging aortic neck anatomy. This study investigated the clinical results and changes in endograft (ap)position during follow-up. METHODS: Patients treated with the CEXC between 2018 and 2022 were included in this prospective single-center study. Computed tomography angiography (CTA) follow-up was grouped into three categories: 0 to 6 (FU1), 7 to 18 (FU2), and 19 to 30 (FU3) months. Clinical end points were endograft-associated complications and reinterventions. CTA analysis included the shortest apposition length (SAL) between the endograft fabric and the first slice where circumferential apposition was lost, shortest fabric distance (SFD) between both renal arteries and the endograft fabric, and maximum infrarenal and suprarenal aortic curvature. FU2 and FU3 were compared with FU1 to establish changes. RESULTS: Included were 46 patients, of whom 36 (78%) had at least one hostile neck feature and 13 (28%) were treated outside instructions for use. Technical success was 100%. Median CTA follow-up was 10 months (2-20 months); 39 patients had a CTA available at FU1, 22 at FU2, and 12 at FU3. At FU1, the median SAL was 21.4 mm (13.2-27.4 mm), which did not significantly change during follow-up. No type I endoleaks, and one type III endoleak at an IBD occurred during follow-up. Two cases of endograft migration (SFD increase >10 mm) were seen during follow-up (one treated outside the instructions for use). Maximum infrarenal and suprarenal aortic curvature did not significantly change during follow-up. CONCLUSIONS: The use of the CEXC in challenging aortic necks enables stable apposition without significant changes in aortic morphology at short-term follow-up.


Assuntos
Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Correção Endovascular de Aneurisma , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/complicações , Estudos Prospectivos , Procedimentos Endovasculares/efeitos adversos , Resultado do Tratamento , Endoleak/diagnóstico por imagem , Endoleak/etiologia , Estudos Retrospectivos , Desenho de Prótese
10.
Cell Mol Neurobiol ; 43(6): 2801-2813, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36680690

RESUMO

Vagus nerve innervates several organs including the heart, stomach, and pancreas among others. Somas of sensory neurons that project through the vagal nerve are located in the nodose ganglion. The presence of purinergic receptors has been reported in neurons and satellite glial cells in several sensory ganglia. In the nodose ganglion, calcium depletion-induced increases in neuron activity can be partly reversed by P2X7 blockers applied directly into the ganglion. The later suggest a possible role of P2X7 receptors in the modulation of neuronal activity within this sensory ganglion. We aimed to characterize the response to P2X7 activation in nodose ganglion neurons under physiological conditions. Using an ex vivo preparation for electrophysiological recordings of the neural discharges of nodose ganglion neurons, we found that treatments with ATP induce transient neuronal activity increases. Also, we found a concentration-dependent increase in neural activity in response to Bz-ATP (ED50 = 0.62 mM, a selective P2X7 receptor agonist), with a clear desensitization pattern when applied every ~ 30 s. Electrophysiological recordings from isolated nodose ganglion neurons reveal no differences in the responses to Bz-ATP and ATP. Finally, we showed that the P2X7 receptor was expressed in the rat nodose ganglion, both in neurons and satellite glial cells. Additionally, a P2X7 receptor negative allosteric modulator decreased the duration of Bz-ATP-induced maximal responses without affecting their amplitude. Our results show the presence of functional P2X7 receptors under physiological conditions within the nodose ganglion of the rat, and suggest that ATP modulation of nodose ganglion activity may be in part mediated by the activation of P2X7 receptors.


Assuntos
Gânglio Nodoso , Receptores Purinérgicos P2X7 , Ratos , Animais , Gânglio Nodoso/fisiologia , Nervo Vago/fisiologia , Trifosfato de Adenosina/farmacologia , Células Receptoras Sensoriais
11.
Aust Endod J ; 49(2): 351-357, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35877115

RESUMO

This study aimed to determine the prevalence of pulp canal obliteration (PCO) and its association with periapical pathology (Hypodense areas) in cone-beam computed tomography (CBCT) scans of anterior teeth. A total of 2161 CBCT scans from patients 18 years or older taken between 2000 and 2020 were selected. Patient-, tooth- and scan-related data were registered. Two calibrated evaluators recorded the number of teeth with PCO ≥4 mm in the cervical third of the roots and the presence or absence of periapical hypodensities (PH). The length of the root canal that was calcified was also determined. Logistic regression analysis was used to determine whether any of the recorded factors influenced the presence of PCO and the presence of periapical pathology in teeth presenting with PCO. The only factor significantly related to the presence of PCO was patient age. The prevalence of PH in teeth exhibiting PCO was 10%.


Assuntos
Doenças da Polpa Dentária , Tomografia Computadorizada de Feixe Cônico Espiral , Humanos , Cavidade Pulpar/diagnóstico por imagem , Prevalência , Tratamento do Canal Radicular/métodos , Tomografia Computadorizada de Feixe Cônico/métodos
12.
J Neurosci ; 42(45): 8406-8415, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36351826

RESUMO

Both the cerebellum and the basal ganglia are known for their roles in motor control and motivated behavior. These two systems have been classically considered as independent structures that coordinate their contributions to behavior via separate cortico-thalamic loops. However, recent evidence demonstrates the presence of a rich set of direct connections between these two regions. Although there is strong evidence for connections in both directions, for brevity we limit our discussion to the better-characterized connections from the cerebellum to the basal ganglia. We review two sets of such connections: disynaptic projections through the thalamus and direct monosynaptic projections to the midbrain dopaminergic nuclei, the VTA and the SNc. In each case, we review the evidence for these pathways from anatomic tracing and physiological recordings, and discuss their potential functional roles. We present evidence that the disynaptic pathway through the thalamus is involved in motor coordination, and that its dysfunction contributes to motor deficits, such as dystonia. We then discuss how cerebellar projections to the VTA and SNc influence dopamine release in the respective targets of these nuclei: the NAc and the dorsal striatum. We argue that the cerebellar projections to the VTA may play a role in reward-based learning and therefore contribute to addictive behavior, whereas the projection to the SNc may contribute to movement vigor. Finally, we speculate how these projections may explain many of the observations that indicate a role for the cerebellum in mental disorders, such as schizophrenia.


Assuntos
Gânglios da Base , Cerebelo , Humanos , Vias Neurais/fisiologia , Gânglios da Base/fisiologia , Cerebelo/fisiologia , Tálamo/fisiologia , Recompensa , Dopamina/metabolismo
13.
Front Cell Dev Biol ; 10: 880107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35846350

RESUMO

Near-infrared (NIR) genetically encoded calcium indicators (GECIs) are becoming powerful tools for neuroscience. Because of their spectral characteristics, the use of NIR GECIs helps to avoid signal loss from the absorption by body pigments, light-scattering, and autofluorescence in mammalian tissues. In addition, NIR GECIs do not suffer from cross-excitation artifacts when used with common fluorescent indicators and optogenetics actuators. Although several NIR GECIs have been developed, there is no NIR GECI currently available that would combine the high brightness in cells and photostability with small size and fast response kinetics. Here, we report a small FRET-based NIR fluorescent calcium indicator iGECInano. We characterize iGECInano in vitro, in non-neuronal mammalian cells, and primary mouse neurons. iGECInano demonstrates the improvement in the signal-to-noise ratio and response kinetics compared to other NIR GECIs.

14.
Entramado ; 18(1): e208, ene.-jun. 2022. tab, graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1384874

RESUMO

RESUMEN El cumplimiento de las metas de los Objetivos de Desarrollo Sostenible y el fortalecimiento de las competencias para ser ciudadanos globales plantea grandes desafios a las naciones y especialmente, a sus sistemas educativos. En este contexto, se propone el diseno de un modelo de coordenadas curriculares dirigido a la formación de competencias para el desarrollo sostenible y la ciudadanía mundial, dentro de la Institución Universitaria Pascual Bravo (Colombia). Desde un enfoque Qualitativo, con alcance descriptivo y el diseno de teoria fundamentada, se realizó una caracterización que devela la necesidad de avanzar en modelos curriculares de educación superior, cuya base sean los conocimientos teóricos y prácticos a fin de promover el desarrollo y los estilos de vida sostenible. A partir de ahi, se plantea modelo de gestión curricular que permita reflexionar sobre la importancia de articular dichas competencias a los propósitos misionales. Se concluye que, con su aplicación, la comunidad académica puede adoptar la herramienta teórica y establecer un diseno que favorezca la actualización curricular con enfoque hacia el desarrollo sostenible.


ABSTRACT The fulfillment ofthe targets of the Sustainable Development Goals and the strengthening of the competencies to be global citizens brings out great challenges to the nations and, especially to their educational systems. In this context, the design of a model of curricular coordinates aimed at the formation of skills for sustainable development and world citizenship, within la Institución Universitaria Pascual Bravo (Pascual Bravo University Institution for its English conversion) (Colombia), is proposed. From a qualitative approach, with a descriptive scope and grounded theory design, a characterization was carried out that reveals the need to advance in higher education curricular models, whose base is theoretical and practical knowledge in order to promote the development and sustainable life styles. From there, a curricular management model is proposed that allows to reflect on the importance of articulating these competencies to the missionary purposes. It is concluded that, with its application, the academic community can adopt the theoretical tool and establish a design that favors curricular updating with a focus on sustainable development.


RESUMO O cumprimento das metas dos Objetivos de Desenvolvimento Sustentável e o reforço das competéncias para a cidadania global representam grandes desafios para as nações e, especialmente, para os seus sistemas educativos. Neste contexto, propomos a conceção de um modelo de coordenadas curriculares visando a formação de competéncias para o desenvolvimento sustentável e a cidadania global, no âmbito da Instituição Universitária Pascual Bravo (Colômbia). A partir de uma abordagem qualitativa, com um âmbito descritivo e uma conceção teórica fundamentada, foi realizada uma caracterização que revela a necessidade de avançar nos modelos curriculares do ensino superior cuja base o conhecimento teórico e prático, a fim de promover o desenvolvimento sustentável e os estilos de vida. Nesta base, é proposto um modelo de gestão curricular que permite refletir sobre a importância de articular estas competéncias com os objetivos da missão da instituição. Conclui-se que, com a sua aplicação, a comunidade académica pode adotar a ferramenta teórica e estabelecer um desenho que favoreça a atualização do currículo com enfoque no desenvolvimento sustentável.

15.
Front Cell Neurosci ; 16: 821088, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431809

RESUMO

Prolonged changes in neural activity trigger homeostatic synaptic plasticity (HSP) allowing neuronal networks to operate within functional ranges. Cell-wide or input-specific adaptations can be induced by pharmacological or genetic manipulations of activity, and by sensory deprivation. Reactive functional changes caused by deafferentation may partially share mechanisms with HSP. Acute hippocampal slices are a suitable model to investigate relatively rapid (hours) modifications occurring after denervation and explore the underlying mechanisms. As during slicing many afferents are cut, we conducted whole-cell recordings of miniature excitatory postsynaptic currents (mEPSCs) in CA1 pyramidal neurons to evaluate changes over the following 12 h. As Schaffer collaterals constitute a major glutamatergic input to these neurons, we also dissected CA3. We observed an average increment in mEPSCs amplitude and a decrease in decay time, suggesting synaptic AMPA receptor upregulation and subunit content modifications. Sorting mEPSC by rise time, a correlate of synapse location along dendrites, revealed amplitude raises at two separate domains. A specific frequency increase was observed in the same domains and was accompanied by a global, unspecific raise. Amplitude and frequency increments were lower at sites initially more active, consistent with local compensatory processes. Transient preincubation with a specific Ca2+/calmodulin-dependent kinase II (CaMKII) inhibitor either blocked or occluded amplitude and frequency upregulation in different synapse populations. Results are consistent with the concurrent development of different known CaMKII-dependent HSP processes. Our observations support that deafferentation causes rapid and diverse compensations resembling classical slow forms of adaptation to inactivity. These results may contribute to understand fast-developing homeostatic or pathological events after brain injury.

16.
Int Endod J ; 55 Suppl 3: 613-636, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35322427

RESUMO

Two fundamental goals of endodontic treatment are to prevent or treat apical periodontitis. From a predictive perspective, several variables can affect the outcome of root canal treatment. Some of these variables depend on intraoperative factors, which include irrigation technique, size of the apical preparation, use of intracanal medicaments or the number of appointments necessary to complete the treatment. However, the outcome may also be affected by host and microbial factors. The intensity of periradicular bone loss or tissue damage, the presence of preoperative pain and associated conditions such as mechanical allodynia and central sensitization, the anatomical complexity of the apical portion of the canal, and the virulence and longevity of the bacterial infection can all have a profound influence on the outcome. Furthermore, numerous medical conditions have been reported to decrease the capability of the immune system to heal the periapical tissues. It is the clinician's responsibility to analyse these variables and incorporate them into the disinfection strategy to maximize the chances of healing. This narrative review will focus on the present status of intracanal medicaments, the clinical indications for their use and future directions for research.


Assuntos
Periodontite Periapical , Irrigantes do Canal Radicular , Hidróxido de Cálcio , Cavidade Pulpar/microbiologia , Desinfecção , Humanos , Periodontite Periapical/tratamento farmacológico , Periodontite Periapical/microbiologia , Tecido Periapical , Irrigantes do Canal Radicular/uso terapêutico , Tratamento do Canal Radicular/métodos
18.
Front Genet ; 12: 640956, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616421

RESUMO

Characterization of allelic variants is relevant to demonstrate associations among genetic background and susceptibility to develop cardiovascular diseases, which are the main cause of death in Chile. Association of APOB, APOE, and MTHFR polymorphisms with higher lipid levels and the risk of developing hypertension and cardiovascular diseases have been described. Thus, the aim of this study was to assess genotype distribution and relative allelic frequency of ApoB rs693, ApoE rs7412, ApoE rs429358, MTHFR rs1801131, and MTHFR rs1801133 allelic variants and their effects on lipid profile in young healthy men and women from Northern Chile. A group of 193 healthy subjects were enrolled for this study. Genotyping of rs693 (APOB), rs7412 and rs429358 (APOE), and rs1801131 and rs1801133 (MTHFR) polymorphisms were performed by real time PCR. In addition, lipid profiles were determined and associated to genetic data. The genotype distribution was APOB rs693 (CC = 37%, CT = 41%, and TT = 22%), APOE rs7412/rs429358 (E4 = 0.06, E3 = 0.91, and E2 = 0.03), MTHFR rs1801131 (AA = 57%, AC = 30%, and CC = 13%), and MTHFR rs1801133 (CC = 20%, CT = 47%, and TT = 33%). The association of the genetic variants with plasma lipid levels showed that women, but not men, carrying APOB mutated allele (T) and Apo E4 allele presented lower values of total cholesterol when compared with C/C homozygous genotype or E3 allele, respectively (p < 0.05). In addition, a subgroup analysis revealed that ApoB C/C homozygous women exhibited higher values of HDL-C when compared with men carrying identical genotype (p < 0.01). On the other hand, women carrying E4 allele exhibited lower values of triglycerides when compared with male carrying identical genotype (p < 0.05). Finally, women carrying mutate allele (C) for MTHFR rs1801131 showed lower levels of triglycerides when compared with A/A homozygous genotype (p < 0.05) and lower levels of LDL-C for MTHFR rs1801133 in females carrying (T) allele when compared with males carrying identical genotype (p < 0.05). In summary, the present data showed that APOB, APOE, and MTHFR single nucleotide polymorphisms are associated to lipid levels in a gender-dependent manner among healthy subjects from Northern Chile, especially in women.

19.
Cells ; 10(7)2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34359972

RESUMO

Alzheimer's disease (AD) is the most common type of dementia in the elderly population. The disease is characterized by progressive memory loss, cerebral atrophy, extensive neuronal loss, synaptic alterations, brain inflammation, extracellular accumulation of amyloid-ß (Aß) plaques, and intracellular accumulation of hyper-phosphorylated tau (p-tau) protein. Many recent clinical trials have failed to show therapeutic benefit, likely because at the time in which patients exhibit clinical symptoms the brain is irreversibly damaged. In recent years, induced pluripotent stem cells (iPSCs) have been suggested as a promising cell therapy to recover brain functionality in neurodegenerative diseases such as AD. To evaluate the potential benefits of iPSCs on AD progression, we stereotaxically injected mouse iPSC-derived neural precursors (iPSC-NPCs) into the hippocampus of aged triple transgenic (3xTg-AD) mice harboring extensive pathological abnormalities typical of AD. Interestingly, iPSC-NPCs transplanted mice showed improved memory, synaptic plasticity, and reduced AD brain pathology, including a reduction of amyloid and tangles deposits. Our findings suggest that iPSC-NPCs might be a useful therapy that could produce benefit at the advanced clinical and pathological stages of AD.


Assuntos
Doença de Alzheimer/terapia , Encefalite/terapia , Células-Tronco Pluripotentes Induzidas/citologia , Plasticidade Neuronal/fisiologia , Peptídeos beta-Amiloides/metabolismo , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Hipocampo/citologia , Camundongos
20.
Neurobiol Dis ; 156: 105425, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34119635

RESUMO

Brain insults like stroke, trauma or infections often lead to blood-brain barrier-dysfunction (BBBd) frequently resulting into epileptogenesis. Affected patients suffer from seizures and cognitive comorbidities that are potentially linked to altered network oscillations. It has been shown that a hippocampal BBBd in rats leads to in vivo seizures and increased power at theta (3-8 Hz), an important type of network oscillations. However, the underlying cellular mechanisms remain poorly understood. At membrane potentials close to the threshold for action potentials (APs) a subpopulation of CA1 pyramidal cells (PCs) displays intrinsic resonant properties due to an interplay of the muscarine-sensitive K+-current (IM) and the persistent Na+-current (INaP). Such resonant neurons are more excitable and generate more APs when stimulated at theta frequencies, being strong candidates for contributing to hippocampal theta oscillations during epileptogenesis. We tested this hypothesis by characterizing changes in intrinsic properties of hippocampal PCs one week after post-stroke epileptogenesis, a model associated with BBBd, using slice electrophysiology and computer modeling. We find a higher proportion of resonant neurons in BBBd compared to sham animals (47 vs. 29%), accompanied by an increase in their excitability. In contrast, BBBd non-resonant neurons showed a reduced excitability, presented with lower impedance and more positive AP threshold. We identify an increase in IM combined with either a reduction in INaP or an increase in ILeak as possible mechanisms underlying the observed changes. Our results support the hypothesis that a higher proportion of more excitable resonant neurons in the hippocampus contributes to increased theta oscillations and an increased likelihood of seizures in a model of post-stroke epileptogenesis.


Assuntos
Hipocampo/fisiopatologia , Células Piramidais/fisiologia , Convulsões/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Ritmo Teta/fisiologia , Animais , Hipocampo/citologia , Masculino , Ratos , Ratos Sprague-Dawley , Convulsões/etiologia , Acidente Vascular Cerebral/complicações
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