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1.
bioRxiv ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38496510

RESUMO

Vibrations are ubiquitous in nature, shaping behavior across the animal kingdom. For mammals, mechanical vibrations acting on the body are detected by mechanoreceptors of the skin and deep tissues and processed by the somatosensory system, while sound waves traveling through air are captured by the cochlea and encoded in the auditory system. Here, we report that mechanical vibrations detected by the body's Pacinian corpuscle neurons, which are unique in their ability to entrain to high frequency (40-1000 Hz) environmental vibrations, are prominently encoded by neurons in the lateral cortex of the inferior colliculus (LCIC) of the midbrain. Remarkably, most LCIC neurons receive convergent Pacinian and auditory input and respond more strongly to coincident tactile-auditory stimulation than to either modality alone. Moreover, the LCIC is required for behavioral responses to high frequency mechanical vibrations. Thus, environmental vibrations captured by Pacinian corpuscles are encoded in the auditory midbrain to mediate behavior.

2.
BMC Biol ; 22(1): 71, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38523261

RESUMO

BACKGROUND: Mitogen-activated protein kinases (MAPKs) preserve cell homeostasis by transducing physicochemical fluctuations of the environment into multiple adaptive responses. These responses involve transcriptional rewiring and the regulation of cell cycle transitions, among others. However, how stress conditions impinge mitotic progression is largely unknown. The mitotic checkpoint is a surveillance mechanism that inhibits mitotic exit in situations of defective chromosome capture, thus preventing the generation of aneuploidies. In this study, we investigate the role of MAPK Pmk1 in the regulation of mitotic exit upon stress. RESULTS: We show that Schizosaccharomyces pombe cells lacking Pmk1, the MAP kinase effector of the cell integrity pathway (CIP), are hypersensitive to microtubule damage and defective in maintaining a metaphase arrest. Epistasis analysis suggests that Pmk1 is involved in maintaining spindle assembly checkpoint (SAC) signaling, and its deletion is additive to the lack of core SAC components such as Mad2 and Mad3. Strikingly, pmk1Δ cells show up to twofold increased levels of the anaphase-promoting complex (APC/C) activator Cdc20Slp1 during unperturbed growth. We demonstrate that Pmk1 physically interacts with Cdc20Slp1 N-terminus through a canonical MAPK docking site. Most important, the Cdc20Slp1 pool is rapidly degraded in stressed cells undergoing mitosis through a mechanism that requires MAPK activity, Mad3, and the proteasome, thus resulting in a delayed mitotic exit. CONCLUSIONS: Our data reveal a novel function of MAPK in preventing mitotic exit and activation of cytokinesis in response to stress. The regulation of Cdc20Slp1 turnover by MAPK Pmk1 provides a key mechanism by which the timing of mitotic exit can be adjusted relative to environmental conditions.


Assuntos
Proteínas de Schizosaccharomyces pombe , Schizosaccharomyces , Schizosaccharomyces/genética , Schizosaccharomyces/metabolismo , Ciclossomo-Complexo Promotor de Anáfase/genética , Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Proteínas de Schizosaccharomyces pombe/genética , Proteínas de Schizosaccharomyces pombe/metabolismo , Proteínas Cdc20/genética , Proteínas Cdc20/metabolismo , Proteínas de Ciclo Celular/metabolismo , Mitose , Fuso Acromático/metabolismo
3.
Nature ; 624(7991): 403-414, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38092914

RESUMO

The brain controls nearly all bodily functions via spinal projecting neurons (SPNs) that carry command signals from the brain to the spinal cord. However, a comprehensive molecular characterization of brain-wide SPNs is still lacking. Here we transcriptionally profiled a total of 65,002 SPNs, identified 76 region-specific SPN types, and mapped these types into a companion atlas of the whole mouse brain1. This taxonomy reveals a three-component organization of SPNs: (1) molecularly homogeneous excitatory SPNs from the cortex, red nucleus and cerebellum with somatotopic spinal terminations suitable for point-to-point communication; (2) heterogeneous populations in the reticular formation with broad spinal termination patterns, suitable for relaying commands related to the activities of the entire spinal cord; and (3) modulatory neurons expressing slow-acting neurotransmitters and/or neuropeptides in the hypothalamus, midbrain and reticular formation for 'gain setting' of brain-spinal signals. In addition, this atlas revealed a LIM homeobox transcription factor code that parcellates the reticulospinal neurons into five molecularly distinct and spatially segregated populations. Finally, we found transcriptional signatures of a subset of SPNs with large soma size and correlated these with fast-firing electrophysiological properties. Together, this study establishes a comprehensive taxonomy of brain-wide SPNs and provides insight into the functional organization of SPNs in mediating brain control of bodily functions.


Assuntos
Encéfalo , Perfilação da Expressão Gênica , Vias Neurais , Neurônios , Medula Espinal , Animais , Camundongos , Hipotálamo , Neurônios/metabolismo , Neuropeptídeos , Medula Espinal/citologia , Medula Espinal/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Neurotransmissores , Mesencéfalo/citologia , Formação Reticular/citologia , Eletrofisiologia , Cerebelo/citologia , Córtex Cerebral/citologia
4.
Arch. cardiol. Méx ; 93(4): 482-489, Oct.-Dec. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1527727

RESUMO

Resumen Introducción: El origen aórtico anómalo de las arterias coronarias tiene una prevalencia estimada del 0.02-5.7% y están potencialmente involucradas con complicaciones en su evolución natural o aquellos que requieran procedimientos intervencionistas hemodinámico y/o quirúrgicos. Puede asociarse a muerte súbita o dañarse durante intervenciones sobre el anillo mitral, aórtico, pulmonar o el cierre percutáneo de un defecto septal interauricular. Objetivo: identificar estos pacientes por diferentes técnicas de imágenes como el ecocardiograma Doppler color transtorácico (ETT), angiotomografía o angiografía coronaria. Métodos: Las técnicas de imágenes utilizadas para la detección de anomalías coronarias fueron el ETT, angiotomografía coronaria multicorte o angiografía coronaria convencional de acuerdo con lo universalmente aceptado. Resultados: Estudio prospectivo realizado desde enero del 2020 a junio del 2021. Se identificaron 15 pacientes y en 12/15 la sospecha fue por ETT y en los tres restantes por angiotomografía coronaria. La arteria circunfleja fue la más involucrada en forma aislada o asociada a otra anomalía coronaria (12/15 pacientes) y en los tres casos restantes la coronaria anómala tuvo un trayecto interarterial, siendo las arterias coronarias derecha y la descendente anterior las afectadas. Conclusiones: El subdiagnóstico por ETT de las anomalías de las arterias coronarias puede deberse a la dificultad para su visualización, sobre todo en la población adulta. Su detección es crucial, ya que puede generar muerte súbita asociada a isquemia miocárdica y arritmias graves o complicar procedimientos intervencionistas sobre el septum interauricular o sobre los anillos mitral, pulmonar y/o aórtico.


Abstract Introduction: The anomalous aortic origin of the coronary arteries has an estimated prevalence of 0.02-5.7%. It can be associated with sudden death when it has an interarterial or intramural pathway or be damaged during interventions on the mitral, pulmonary and/or aortic annulus or percutaneous closure of an interatrial septal defect. Objective: To identify these patients by imaging techniques such as transthoracic color Doppler echocardiography (TTE), computed tomography (CT) multislice angiography or coronary angiography. Methods: The imaging techniques used for the detection of coronary anomalies were TTE, multislice coronary angiography or coronary angiography according to what is generally accepted. Results: Fifteen patients were identified; in 12 of them the suspicion was due to TTE and in the remaining 3, CT multislice angiography was diagnostic. The circumflex artery was the coronary artery most involved, associated or not with another coronary anomaly (12/15 patients) and in the other three cases, the anomalous coronary artery had an interarterial course, with the right coronary arteries and the anterior descending coronary arteries being involved. Conclusions: The under diagnosis by TTE of coronary artery abnormalities may be due to the difficulty of visualization that is accentuated with age. Their detection is crucial because they can both, lead to sudden death associated with an intramural and/or interarterial pathway and complicate an interventional procedure on the interatrial septum or within the mitral, pulmonary and/or aortic rings.

5.
Arch Cardiol Mex ; 93(4): 482-489, 2023 09 05.
Artigo em Espanhol | MEDLINE | ID: mdl-37669688

RESUMO

Introduction: The anomalous aortic origin of the coronary arteries has an estimated prevalence of 0.02-5.7%. It can be associated with sudden death when it has an interarterial or intramural pathway or be damaged during interventions on the mitral, pulmonary and/or aortic annulus or percutaneous closure of an interatrial septal defect. Objective: To identify these patients by imaging techniques such as transthoracic color Doppler echocardiography (TTE), computed tomography (CT) multislice angiography or coronary angiography. Methods: The imaging techniques used for the detection of coronary anomalies were TTE, multislice coronary angiography or coronary angiography according to what is generally accepted. Results: Fifteen patients were identified; in 12 of them the suspicion was due to TTE and in the remaining 3, CT multislice angiography was diagnostic. The circumflex artery was the coronary artery most involved, associated or not with another coronary anomaly (12/15 patients) and in the other three cases, the anomalous coronary artery had an interarterial course, with the right coronary arteries and the anterior descending coronary arteries being involved. Conclusions: The under diagnosis by TTE of coronary artery abnormalities may be due to the difficulty of visualization that is accentuated with age. Their detection is crucial because they can both, lead to sudden death associated with an intramural and/or interarterial pathway and complicate an interventional procedure on the interatrial septum or within the mitral, pulmonary and/or aortic rings.


Introducción: El origen aórtico anómalo de las arterias coronarias tiene una prevalencia estimada del 0.02-5.7% y están potencialmente involucradas con complicaciones en su evolución natural o aquellos que requieran procedimientos intervencionistas hemodinámico y/o quirúrgicos. Puede asociarse a muerte súbita o dañarse durante intervenciones sobre el anillo mitral, aórtico, pulmonar o el cierre percutáneo de un defecto septal interauricular. Objetivo: Identificar estos pacientes por diferentes técnicas de imágenes como el ecocardiograma Doppler color transtorácico (ETT), angiotomografía o angiografía coronaria. Métodos: Las técnicas de imágenes utilizadas para la detección de anomalías coronarias fueron el ETT, angiotomografía coronaria multicorte o angiografía coronaria convencional de acuerdo con lo universalmente aceptado. Resultados: Estudio prospectivo realizado desde enero del 2020 a junio del 2021. Se identificaron 15 pacientes y en 12/15 la sospecha fue por ETT y en los tres restantes por angiotomografía coronaria. La arteria circunfleja fue la más involucrada en forma aislada o asociada a otra anomalía coronaria (12/15 pacientes) y en los tres casos restantes la coronaria anómala tuvo un trayecto interarterial, siendo las arterias coronarias derecha y la descendente anterior las afectadas. Conclusiones: El subdiagnóstico por ETT de las anomalías de las arterias coronarias puede deberse a la dificultad para su visualización, sobre todo en la población adulta. Su detección es crucial, ya que puede generar muerte súbita asociada a isquemia miocárdica y arritmias graves o complicar procedimientos intervencionistas sobre el septum interauricular o sobre los anillos mitral, pulmonar y/o aórtico.


Assuntos
Anomalias dos Vasos Coronários , Humanos , Anomalias dos Vasos Coronários/diagnóstico por imagem , Anomalias dos Vasos Coronários/complicações , Aorta , Tomografia Computadorizada por Raios X , Angiografia Coronária/métodos , Morte Súbita
6.
J Thromb Thrombolysis ; 56(3): 433-438, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37407771

RESUMO

In this study we aimed to evaluate and compare the overall performance of the Khorana, PROTECHT, and CONKO scores as predictive scores for the occurrence of venous thromboembolism (VTE) among ambulatory Hispanic patients with solid tumors. We included all outpatients with newly diagnosed solid tumors receiving systemic chemotherapy in Hospital San Juan Dios, San José, Costa Rica, from January to December 2021. For each patient the Khorana, PROTECHT, and CONKO scores were calculated at the beginning of treatment. The sixth-month cumulative incidence of VTE was estimated using the Fine & Gray competing risk model. The receiver operating characteristic (ROC) curve was used to assess the performance of each predictive tool through the analysis of the c-statistic, sensitivity, and specificity. A total of 708 patients were included in the research. After a median follow-up of 8.13 months, the cumulative VTE incidence at six months was 4.45% (95%CI: 3.25-6.91%) for the overall population. At the conventional positivity threshold of 3 points, these scores classified from 17.7 to 32.5% of all patients as high-risk for VTE. Patients belonging to the high-risk category of the Khorana, PROTECHT, and CONKO scores had significantly higher risk of VTE in comparison to low-risk patients (Khorana score: Hazard Ratio (HR): 2.66; 95%CI:1.20-5.89; p = 0.042; PROTECHT score: HR: 3.44; 95%CI:1.63-7.21; p = 0.001; CONKO score HR: 3.68; 95%CI:1.72-7.85; p = 0.001). The c-statistic of the ROC curve was: 0.62 (95%CI: 0.52-0.72), 0.62 (95%CI: 0.52-0.73), and 0.65 (95%CI: 0.56-0.76) for the Khorana, PROTECHT, and CONKO scores, respectively; with similar sensitivity (range: 67-70%) and specificity (range: 52-62%) among them. For Hispanic patients with solid tumors the Khorana, PROTECHT, and CONKO scores accurately categorize their risk of VTE. However, the overall discriminatory performance of these models remains poor (c-statistic from 0.62 to 0.65) for predicting all patients at risk for thromboembolic events.


Assuntos
Neoplasias , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Neoplasias/diagnóstico , Pacientes Ambulatoriais , Hispânico ou Latino , Fatores de Risco , Estudos Retrospectivos , Medição de Risco
7.
J Clin Med ; 12(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37297824

RESUMO

INTRODUCTION: A significant increase in the use of computed tomography with pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism (PE) has been observed in the past twenty years. We aimed to investigate whether the validated diagnostic predictive tools and D-dimers were adequately utilized in a large public hospital in New York City. METHODS: We conducted a retrospective review of patients who underwent CTPA for the specific indication of ruling out PE over a period of one year. Two independent reviewers, blinded to each other and to the CTPA and D-dimer results, estimated the clinical probability (CP) of PE using Well's score, the YEARS algorithm, and the revised Geneva score. Patients were classified based on the presence or absence of PE in the CTPA. RESULTS: A total of 917 patients were included in the analysis (median age: 57 years, female: 59%). The clinical probability of PE was considered low by both independent reviewers in 563 (61.4%), 487 (55%), and 184 (20.1%) patients based on Well's score, the YEARS algorithm, and the revised Geneva score, respectively. D-dimer testing was conducted in less than half of the patients who were deemed to have low CP for PE by both independent reviewers. Using a D-dimer cut-off of <500 ng/mL or the age-adjusted cut-off in patients with a low CP of PE would have missed only a small number of mainly subsegmental PE. All three tools, when combined with D-dimer < 500 ng/mL or 95%. CONCLUSION: All three validated diagnostic predictive tools were found to have significant diagnostic value in ruling out PE when combined with a D-dimer cut-off of <500 ng/mL or the age-adjusted cut-off. Excessive use of CTPA was likely secondary to suboptimal use of diagnostic predictive tools.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37056683

RESUMO

Background: Inhaled corticosteroids (ICSs) combined with bronchodilators have been identified to improve outcomes in COPD but also to be associated with certain adverse effects. Objective: We performed a systematic review and meta-analysis to compile and summarize data on the efficacy and safety of dosing levels (high versus medium/low) of ICS alongside ancillary bronchodilators following PRISMA guidelines. Data Sources: Medline and Embase were systematically searched until December 2021. Randomized, clinical trials (RCTs) that met predefined inclusion criteria were included. Data Extraction: Risk ratios (RRs) with 95% confidence intervals (CI) were extracted. Any acute exacerbation of COPD (AECOPD) risk was chosen as the primary efficacy outcome, mortality rate as the primary safety outcome, moderate/severe AECOPD risk as the secondary efficacy outcome and pneumonia risk as the secondary safety outcome. Subgroup analyses of individual ICS agents, of patients with baseline moderate/severe/very severe COPD and of patients with recent COPD exacerbation history were also performed. A random-effects model was used. Results: We included 13 RCTs in our study. No data on low doses were included in the analysis. High dose ICS was not associated with a statistically significant difference in any AECOPD risk (RR: 0.98, 95% CI: 0.91-1.05, I2: 41.3%), mortality rate (RR: 0.99, 95% CI: 0.75-1.32, I2: 0.0%), moderate/severe AECOPD risk (RR: 1.01, 95% CI: 0.96-1.06, I2: 0.0%) or pneumonia risk (RR: 1.07, 95% CI: 0.86 -1.33, I2: 9.3%) compared to medium dose ICS. The same trend was identified with the several subgroup analyses. Conclusion: Our study collected RCTs investigating the optimal dosing level of ICS prescribed alongside ancillary bronchodilators to patients with COPD. We identified that the high ICS dose neither reduces AECOPD risk and mortality rates nor increases pneumonia risk relative to the medium dose.


Assuntos
Pneumonia , Doença Pulmonar Obstrutiva Crônica , Humanos , Broncodilatadores , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Corticosteroides , Pneumonia/induzido quimicamente , Pneumonia/diagnóstico , Pneumonia/tratamento farmacológico , Administração por Inalação
9.
Front Cell Dev Biol ; 10: 941870, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36092739

RESUMO

The heterotrimeric G protein family plays essential roles during a varied array of cellular events; thus, its deregulation can seriously alter signaling events and the overall state of the cell. Heterotrimeric G-proteins have three subunits (α, ß, γ) and are subdivided into four families, Gαi, Gα12/13, Gαq, and Gαs. These proteins cycle between an inactive Gα-GDP state and active Gα-GTP state, triggered canonically by the G-protein coupled receptor (GPCR) and by other accessory proteins receptors independent also known as AGS (Activators of G-protein Signaling). In this review, we summarize research data specific for the Gαi family. This family has the largest number of individual members, including Gαi1, Gαi2, Gαi3, Gαo, Gαt, Gαg, and Gαz, and constitutes the majority of G proteins α subunits expressed in a tissue or cell. Gαi was initially described by its inhibitory function on adenylyl cyclase activity, decreasing cAMP levels. Interestingly, today Gi family G-protein have been reported to be importantly involved in the immune system function. Here, we discuss the impact of Gαi on non-canonical effector proteins, such as c-Src, ERK1/2, phospholipase-C (PLC), and proteins from the Rho GTPase family members, all of them essential signaling pathways regulating a wide range of physiological processes.

10.
Stroke ; 53(11): 3410-3418, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36000394

RESUMO

BACKGROUND: COVID-19 has been frequently associated with an increased risk of thrombotic complications. There have also been reports of an increased likelihood of stroke, although its true incidence in patients with COVID-19 is currently unknown. METHODS: Electronic databases PubMed and Scopus were searched from inception up to July 30, 2021 to identify randomized controlled studies in patients with confirmed COVID-19 undergoing one or more interventions. Studies were screened for eligibility using a predefined inclusion criterion and selected using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A random-effects model meta-analysis was conducted, and heterogeneity was assessed using I-squared test. RESULTS: Out of 3960 potentially eligible articles, 77 randomized studies (38 732 patients) were included. Mean age of the study population was 55±9.3 years. Females constituted 38% of the study population and mean duration of follow-up after study enrollment was 23±12.9 days. Cumulative incidence of stroke in the overall study population was 0.001 (95% CI, 0.001-0.002) with a total of 65 events in 38 732 patients, corresponding to an absolute incidence of 0.168%. Incidence of stroke in the inpatient population was 0.001 (95% CI, 0.001-0.002; 65 events in 37 069 patients), corresponding to an absolute incidence of 0.175%. No strokes were observed in the outpatient setting. CONCLUSIONS: The overall incidence of stroke in patients with COVID-19 appears to be lower than that reported in previous observational reports.


Assuntos
COVID-19 , Acidente Vascular Cerebral , Feminino , Humanos , Pessoa de Meia-Idade , Incidência , COVID-19/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/epidemiologia
11.
Hear Res ; 425: 108516, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35606211

RESUMO

The cochlear efferent system comprises multiple populations of brainstem neurons whose axons project to the cochlea, and whose responses to acoustic stimuli lead to regulation of auditory sensitivity. The major groups of efferent neurons are found in the superior olivary complex and are likely activated by neurons of the cochlear nucleus, thus forming a simple reflex pathway back to the cochlea. The peripheral actions of only one of these efferent cell types has been well described. Moreover, the efferent neurons are not well understood at the cellular- and circuit-levels. For example, ample demonstration of descending projections to efferent neurons raises the question of whether these additional inputs constitute a mechanism for modulation of relay function or instead play a more prominent role in driving the efferent response. Related to this is the question of synaptic plasticity at these synapses, which has the potential to differentially scale the degree of efferent activation across time, depending on the input pathway. This review will explore central nervous system aspects of the efferent system, the physiological properties of the neurons, their synaptic inputs, their modulation, and the effects of efferent axon collaterals within the brainstem.


Assuntos
Cóclea , Núcleo Coclear , Estimulação Acústica , Vias Auditivas , Tronco Encefálico/fisiologia , Cóclea/fisiologia , Núcleo Coclear/fisiologia , Vias Eferentes/fisiologia , Neurônios Eferentes/fisiologia , Núcleo Olivar/fisiologia
12.
Ecancermedicalscience ; 16: 1470, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36819798

RESUMO

Background: The Khorana risk score (KRS) for prognosis of venous thromboembolism (VTE) has been rarely explored in Hispanic populations. Objective: To determine the value of the KRS for prediction of VTE and overall survival (OS) among Hispanic individuals with cancer. Methods: We retrospectively evaluated all outpatients with newly diagnosed solid tumours receiving systemic chemotherapy in Hospital San Juan Dios, San José, Costa Rica, from January to December 2021. The 6-month cumulative VTE incidence according to the KRS categories was estimated using the Fine & Gray competing risk model. A Kaplan-Meier analysis was used to compare OS among KRS categories. The Cox regression analysis was performed to calculate the hazard ratio (HR) and its corresponding 95% confidence interval (CI). The receiver operating characteristic (ROC) analysis was performed to identify the optimal cutoff value to predict VTE during follow-up. Results: A total of 708 patients were included in the analysis. After a median follow-up of 8.13 months, the cumulative incidence of VTE at 6 months was 1.56% (95% CI: 0.83%-6.82%), 4.83% (95% CI: 2.81%-7.66%) and 8.84% (95% CI: 4.30%-15.42%) for low-, intermediate- and high-risk Khorana score categories, respectively (Gray's p value: 0.0178). The optimal cutoff for the KRS to predict VTE was 2 (area under the ROC curve: 0.65; 95% CI: 0.55-0.756). The KRS was independently associated with overall mortality (HR: 1.83; 95% CI: 1.46-2.29; p < 0.001, for the comparison of 'high-risk' and 'low-risk' KRS). Conclusions: The KRS is a valid tool to predict VTE and mortality in a cohort of Hispanic outpatients with newly diagnosed solid tumours.

13.
Elife ; 102021 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-34250904

RESUMO

Activity in each brain region is shaped by the convergence of ascending and descending axonal pathways, and the balance and characteristics of these determine the neural output. The medial olivocochlear (MOC) efferent system is part of a reflex arc that critically controls auditory sensitivity. Multiple central pathways contact MOC neurons, raising the question of how a reflex arc could be engaged by diverse inputs. We examined functional properties of synapses onto brainstem MOC neurons from ascending (ventral cochlear nucleus, VCN) and descending (inferior colliculus, IC) sources in mice using an optogenetic approach. We found that these pathways exhibited opposing forms of short-term plasticity, with the VCN input showing depression and the IC input showing marked facilitation. By using a conductance-clamp approach, we found that combinations of facilitating and depressing inputs enabled firing of MOC neurons over a surprisingly wide dynamic range, suggesting an essential role for descending signaling to a brainstem nucleus.


Assuntos
Cóclea/fisiologia , Núcleo Coclear/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios Eferentes/fisiologia , Estimulação Acústica/métodos , Animais , Vias Auditivas/fisiologia , Axônios/fisiologia , Tronco Encefálico/fisiologia , Nervo Coclear/fisiologia , Colículos Inferiores/fisiologia , Camundongos , Núcleo Olivar/fisiologia , Optogenética/métodos , Sinapses/fisiologia
14.
Elife ; 92020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33141020

RESUMO

Auditory processing depends upon inhibitory signaling by interneurons, even at its earliest stages in the ventral cochlear nucleus (VCN). Remarkably, to date only a single subtype of inhibitory neuron has been documented in the VCN, a projection neuron termed the D-stellate cell. With the use of a transgenic mouse line, optical clearing, and imaging techniques, combined with electrophysiological tools, we revealed a population of glycinergic cells in the VCN distinct from the D-stellate cell. These multipolar glycinergic cells were smaller in soma size and dendritic area, but over ten-fold more numerous than D-stellate cells. They were activated by auditory nerve and T-stellate cells, and made local inhibitory synaptic contacts on principal cells of the VCN. Given their abundance, combined with their narrow dendritic fields and axonal projections, it is likely that these neurons, here termed L-stellate cells, play a significant role in frequency-specific processing of acoustic signals.


Assuntos
Núcleo Coclear/citologia , Interneurônios/citologia , Animais , Percepção Auditiva/fisiologia , Núcleo Coclear/fisiologia , Feminino , Interneurônios/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
15.
Cancer Treat Res Commun ; 23: 100175, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32361352

RESUMO

PURPOSE: To compare the efficacy and safety profile of the combination of cyclin-dependent kinase 4/6 (CDK 4/6) inhibitors and fulvestrant versus fulvestrant alone in previously treated patients with advanced hormone-receptor positive breast cancer. METHODS: Phase III randomized clinical trials (RCTs) were retrieved from a systematic review of electronic databases. A random-effect model was employed to determine the pooled hazard ratio (HR) for Progression-Free Survival (PFS) and Overall Survival (OS) using the inverse-variance method. The Mantel Haenszel method was used to calculate the pooled odds ratio (OR) for treatment-related side effects. Heterogeneity was measured using the tau-squared and I2 statistics. RESULTS: Three phase III RCTs (n = 1916) were included in the systematic review. Use of abemaciclib, palbociclib, or ribociclib in combination with fulvestrant was significantly associated with longer PFS compared to use of fulvestrant alone (HR: 0.53; 95%CI: 0.47-0.60; p<0.00001), with no significant heterogeneity found among trials. Similarly, OS was significantly longer for patients who received combination therapy in comparison with those allocated to receive fulvestrant alone (HR: 0.77; 95%CI: 0.67-0.89; p<0.0004). The overall odds ratio of serious adverse events (AE) was not significantly increased with the use of the combination therapy (OR: 1.51; 95%CI: 0.74-3.08), with significant heterogeneity found among trials (tau2=0.34; I2=86%; p = 0.0006). CONCLUSION: The addition of CDK 4/6 inhibitors (either abemaciclib, palbociclib, or ribociclib) to fulvestrant significantly improved PFS and OS in comparison with fulvestrant alone in patients previously treated with endocrine therapy for advanced breast cancer. No significant heterogeneity was found among CDK 4/6 inhibitors.

16.
Eur J Surg Oncol ; 45(6): 963-968, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30745134

RESUMO

OBJECTIVE: To evaluate the pathologic response after neoadjuvant chemotherapy in patients with breast cancer according to the stromal tumor-infiltrating lymphocytes (TILs) as well as the evaluation of overall and disease-free survival according to TILs. METHODS: A six years (2008-2013) review was done including patients with locally advanced breast cancer that received neoadjuvant therapy and then surgery. An evaluation of the percentage of TILs was done in the pretreatment biopsies and a correlation analysis and survival curves were done. RESULTS: 187 patients were evaluated. The pathological complete response (pCR) in patients with TILs ≥30% was 58.5%, and in patients with TILs < 30% was 11% (p <0.001). An Odds Ratio of 8.85 was obtained in patients with TILs ≥30% to achieve a pCR. This relationship was seen in patients with HER2-enriched and triple-negative subtypes. No correlation between TILs and survival was obtained (OS: log-rank; p = 0.834; DFS: log-rank; p = 0.937). CONCLUSIONS: The study of TILs is important because they represent an additional tool to predict the response to neoadjuvant treatment mostly in HER2-enriched and triple-negative subtypes of breast cancer.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/diagnóstico , Linfócitos do Interstício Tumoral/patologia , Estadiamento de Neoplasias/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/terapia , Feminino , Humanos , Mastectomia/métodos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Venezuela/epidemiologia
17.
Ecancermedicalscience ; 12: 833, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29910830

RESUMO

Aggressive fibromatosis comprises connective tissue tumours that represent 0.03% of all bodily neoplasms, occurring more often in the abdominal wall, mesentery, and extremities; its location in the breast constitutes a very infrequent type of lesion. Its pathogenesis is diverse and its relationship with augmentation mastoplasty is still unclear. Four cases of aggressive breast fibromatosis following augmentation mastoplasty are reported in this article.

18.
Ecancermedicalscience ; 11: 774, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29104611

RESUMO

OBJECTIVE: To determine the false-negative rate, sensitivity, and diagnostic accuracy of the frozen section analysis of the sentinel lymph node (SLN) biopsy in early-stage breast cancer compared to the definitive section and to identify the factors that could be associated with the appearance of false-negative cases. Secondarily, to evaluate the pathological results of cases submitted to completion axillary lymph node dissection (ALND) for positive SLN. METHODS: We performed a five-year review of cases (2011-2015), including patients with early-stage breast cancer undergoing SLN biopsy, with frozen section evaluation and subsequent definitive pathological analysis. These results were compared to calculate the false-negative rate and the factors associated with it. The histopathological findings were also evaluated in patients submitted to completion ALND. RESULTS: A total of 281 patients were evaluated, identifying 18 cases with frozen section results as false negative (false-negative rate: 23.7%), and 55.5% of these cases were micrometastases. The false-negative rate in SLN with macrometastasis was 13.1% and for micrometastasis cases was 66.7% (p < 0.001). True-positive patients that were submitted to completion ALND had additional axillary lymph nodes with metastases in 28% of cases, whereas the group of false negatives had additional positive axillary lymph nodes in 40% of patients (p = 0.62). CONCLUSION: Frozen section analysis had a false-negative rate acceptable in SLN biopsy in our institution, and the micrometastasis in the SLN was the most important factor associated with the appearance of this phenomenon.

19.
Neuron ; 96(1): 73-80.e4, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28919175

RESUMO

AMPARs mediate the briefest synaptic currents in the brain by virtue of their rapid gating kinetics. However, at the mossy fiber-to-unipolar brush cell synapse in the cerebellum, AMPAR-mediated EPSCs last for hundreds of milliseconds, and it has been proposed that this time course reflects slow diffusion from a complex synaptic space. We show that upon release of glutamate, synaptic AMPARs were desensitized by transmitter by >90%. As glutamate levels subsequently fell, recovery of transmission occurred due to the presence of the AMPAR accessory protein stargazin that enhances the AMPAR response to low levels of transmitter. This gradual increase in receptor activity following desensitization accounted for the majority of synaptic transmission at this synapse. Moreover, the amplitude, duration, and shape of the synaptic response was tightly controlled by plasma membrane glutamate transporters, indicating that clearance of synaptic glutamate during the slow EPSC is dictated by an uptake process.


Assuntos
Sistema X-AG de Transporte de Aminoácidos/fisiologia , Canais de Cálcio/fisiologia , Ácido Glutâmico/fisiologia , Receptores de AMPA/fisiologia , Transmissão Sináptica/fisiologia , Animais , Canais de Cálcio/genética , Cerebelo/fisiologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Camundongos , Camundongos Transgênicos
20.
Entramado ; 13(1)jun. 2017.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1534404

RESUMO

El presente artículo tiene como objetivo contribuir a la reflexión sobre las prácticas pedagógicas y didácticas orientadas al alcance del logro académico que los docentes desarrollan en el escenario educativo de la escuela. Del mismo modo, observar si los ambientes de aprendizaje se encuentran direccionados a potenciar los saberes previos, la construcción de planteamientos y posiciones que permiten comprender desde una posición crítica las condiciones del contexto de desenvolvimiento de las y los educandos. Y por último, reconocer los cambios que deben asimilar los docentes en una sociedad que paulatinamente exige nuevos conocimientos y competencias. Por tanto, es una invitación a repensar las acciones pedagógicas, los procesos de enseñanza aprendizaje, las didácticas en las que se apoyan los docentes para orientar el alcance del logro académico de las y los educandos.


This article aims to contribute to the reflection on pedagogical and didactic practices oriented to the scope of academic achievement and teachers developed in the educational setting for the school. In the same way see if learning environments are directed to enhance the knowledge previous to the construction of approaches and positions that allow to understand from a position criticized conditions in the context of unfolding of the learners. And finally to recognize the changes that must be gradually assimilate the teachers in a society that requires new knowledge and skills. Therefore, it is an invitation to rethink the pedagogical actions, teaching-learning processes, and the didactics that support teachers to guide to achieve the academic achievement of the students.


Este artigo pretende contribuir para a reflexão sobre as práticas pedagógicas e didáticas destinadas a alcançar o desempenho acadêmico que os professores desenvolvem cenário educacional na escola. Da mesma forma, observar se os ambientes de aprendizagem são direcionados para aumentar o conhecimento prévio, a construção de abordagens e posições que permitam a compreensão de um condições de contexto posição crítica e desenvolvimento dos alunos. E, finalmente, reconhecer as mudanças que os professores deveriam assimilar em uma sociedade que exige gradualmente novos conhecimentos e habilidades. Portanto, é um convite a repensar os processos de ações, de ensino e aprendizagem pedagógicas, ensinando nas quais os professores são suportados para orientar o alcance e desempenho acadêmico dos estudantes.

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