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1.
Proc Natl Acad Sci U S A ; 119(28): e2107797119, 2022 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-35867767

RESUMEN

Declarative memory encoding, consolidation, and retrieval require the integration of elements encoded in widespread cortical locations. The mechanism whereby such "binding" of different components of mental events into unified representations occurs is unknown. The "binding-by-synchrony" theory proposes that distributed encoding areas are bound by synchronous oscillations enabling enhanced communication. However, evidence for such oscillations is sparse. Brief high-frequency oscillations ("ripples") occur in the hippocampus and cortex and help organize memory recall and consolidation. Here, using intracranial recordings in humans, we report that these ∼70-ms-duration, 90-Hz ripples often couple (within ±500 ms), co-occur (≥ 25-ms overlap), and, crucially, phase-lock (have consistent phase lags) between widely distributed focal cortical locations during both sleep and waking, even between hemispheres. Cortical ripple co-occurrence is facilitated through activation across multiple sites, and phase locking increases with more cortical sites corippling. Ripples in all cortical areas co-occur with hippocampal ripples but do not phase-lock with them, further suggesting that cortico-cortical synchrony is mediated by cortico-cortical connections. Ripple phase lags vary across sleep nights, consistent with participation in different networks. During waking, we show that hippocampo-cortical and cortico-cortical coripples increase preceding successful delayed memory recall, when binding between the cue and response is essential. Ripples increase and phase-modulate unit firing, and coripples increase high-frequency correlations between areas, suggesting synchronized unit spiking facilitating information exchange. co-occurrence, phase synchrony, and high-frequency correlation are maintained with little decrement over very long distances (25 cm). Hippocampo-cortico-cortical coripples appear to possess the essential properties necessary to support binding by synchrony during memory retrieval and perhaps generally in cognition.


Asunto(s)
Corteza Cerebral , Hipocampo , Consolidación de la Memoria , Recuerdo Mental , Sueño , Vigilia , Corteza Cerebral/fisiología , Electrocorticografía , Hipocampo/fisiología , Humanos , Consolidación de la Memoria/fisiología , Recuerdo Mental/fisiología , Sueño/fisiología , Vigilia/fisiología
2.
RNA ; 28(6): 905-915, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35296539

RESUMEN

Gene expression analysis requires accurate measurements of global RNA degradation rates, earlier problematic with methods disruptive to cell physiology. Recently, metabolic RNA labeling emerged as an efficient and minimally invasive technique applied in mammalian cells. Here, we have adapted SH-linked alkylation for the metabolic sequencing of RNA (SLAM-seq) for a global mRNA stability study in yeast using 4-thiouracil pulse-chase labeling. We assign high-confidence half-life estimates for 67.5% of expressed ORFs, and measure a median half-life of 9.4 min. For mRNAs where half-life estimates exist in the literature, their ranking order was in good agreement with previous data, indicating that SLAM-seq efficiently classifies stable and unstable transcripts. We then leveraged our yeast protocol to identify targets of the nonsense-mediated decay (NMD) pathway by measuring the change in RNA half-lives, instead of steady-state RNA level changes. With SLAM-seq, we assign 580 transcripts as putative NMD targets, based on their measured half-lives in wild-type and upf3Δ mutants. We find 225 novel targets, and observe a strong agreement with previous reports of NMD targets, 61.2% of our candidates being identified in previous studies. This indicates that SLAM-seq is a simpler and more economic method for global quantification of mRNA half-lives. Our adaptation for yeast yielded global quantitative measures of the NMD effect on transcript half-lives, high correlation with RNA half-lives measured previously with more technically challenging protocols, and identification of novel NMD regulated transcripts that escaped prior detection.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Animales , Mamíferos/genética , Degradación de ARNm Mediada por Codón sin Sentido , Sistemas de Lectura Abierta , Estabilidad del ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
3.
J Bioenerg Biomembr ; 56(3): 205-219, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38436904

RESUMEN

The plasma membrane Ca2+-ATPase (PMCA) is crucial for the fine tuning of intracellular calcium levels in eukaryotic cells. In this study, we show the presence of CARC sequences in all human and rat PMCA isoforms and we performed further analysis by molecular dynamics simulations. This analysis focuses on PMCA1, containing three CARC motifs, and PMCA4, with four CARC domains. In PMCA1, two CARC motifs reside within transmembrane domains, while the third is situated at the intracellular interface. The simulations depict more stable RMSD values and lower RMSF fluctuations in the presence of cholesterol, emphasizing its potential stabilizing effect. In PMCA4, a distinct dynamic was found. Notably, the total energy differences between simulations with cholesterol and phospholipids are pronounced in PMCA4 compared to PMCA1. RMSD values for PMCA4 indicate a more energetically favorable conformation in the presence of cholesterol, suggesting a robust interaction between CARCs and this lipid in the membranes. Furthermore, RMSF analysis for CARCs in both PMCA isoforms exhibit lower values in the presence of cholesterol compared to POPC alone. The analysis of H-bond occupancy and total energy values strongly suggests the potential interaction of CARCs with cholesterol. Given the crucial role of PMCAs in physiological calcium regulation and their involvement in diverse pathological processes, this study underscores the significance of CARC motifs and their interaction with cholesterol in elucidating PMCA function. These insights into the energetic preferences associated with CARC-cholesterol interactions offer valuable implications for understanding PMCA function in maintaining calcium homeostasis and addressing potential associated pathologies.


Asunto(s)
Colesterol , ATPasas Transportadoras de Calcio de la Membrana Plasmática , ATPasas Transportadoras de Calcio de la Membrana Plasmática/metabolismo , ATPasas Transportadoras de Calcio de la Membrana Plasmática/química , Colesterol/metabolismo , Humanos , Animales , Ratas , Simulación de Dinámica Molecular , Secuencias de Aminoácidos , Membrana Celular/metabolismo
4.
Epilepsia ; 65(6): e79-e86, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38625609

RESUMEN

In patients with drug-resistant epilepsy (DRE) who are not candidates for resective surgery, various thalamic nuclei, including the anterior, centromedian, and pulvinar nuclei, have been extensively investigated as targets for neuromodulation. However, the therapeutic effects of different targets for thalamic neuromodulation on various types of epilepsy are not well understood. Here, we present a 32-year-old patient with multifocal bilateral temporoparieto-occipital epilepsy and bilateral malformations of cortical development (MCDs) who underwent bilateral stereoelectroencephalographic (SEEG) recordings of the aforementioned three thalamic nuclei bilaterally. The change in the rate of interictal epileptiform discharges (IEDs) from baseline were compared in temporal, central, parietal, and occipital regions after direct electrical stimulation (DES) of each thalamic nucleus. A significant decrease in the rate of IEDs (33% from baseline) in the posterior quadrant regions was noted in the ipsilateral as well as contralateral hemisphere following DES of the pulvinar. A scoping review was also performed to better understand the current standpoint of pulvinar thalamic stimulation in the treatment of DRE. The therapeutic effect of neuromodulation can differ among thalamic nuclei targets and epileptogenic zones (EZs). In patients with multifocal EZs with extensive MCDs, personalized thalamic targeting could be achieved through DES with thalamic SEEG electrodes.


Asunto(s)
Epilepsia Refractaria , Electroencefalografía , Pulvinar , Humanos , Adulto , Epilepsia Refractaria/terapia , Epilepsia Refractaria/fisiopatología , Electroencefalografía/métodos , Estimulación Encefálica Profunda/métodos , Técnicas Estereotáxicas , Prueba de Estudio Conceptual , Tálamo/fisiopatología , Masculino , Terapia por Estimulación Eléctrica/métodos
5.
Dis Colon Rectum ; 67(1): 90-96, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38091415

RESUMEN

BACKGROUND: Using standard anterior approaches, consistent R0 resection of locally advanced primary and recurrent rectal and anal cancer involving the deep pelvic sidewall may be unattainable. Therefore, to improve R0 resection rates, we have used a posterior-first, then anterior 2-stage approach to resection of tumors in this location. OBJECTIVE: To assess the R0 resection rate and surgical outcomes of the first 10 patients operated on using this approach. DESIGN: We conducted a retrospective case series review of our prospectively maintained surgical pathology and tumor registries. SETTING: This study was conducted at the Mayo Clinic in Rochester, Minnesota. PATIENTS: Ten patients (6 female individuals, median age 53.5 years) with primary or recurrent anal or rectal cancer treated with a posterior-first, then anterior 2-stage approach were identified. MAIN OUTCOME MEASURES: The primary outcome measures were the R0 resection rate and surgical outcomes. RESULTS: An R0 resection was achieved in all 10 patients. Nine patients developed 1 or more 30-day Clavien-Dindo grade III complications. Nine patients developed gluteal wound complications ranging from superficial wound dehiscence to flap necrosis. During the follow-up period, 4 patients were found to have metastatic disease and 1 patient had local re-recurrence. LIMITATIONS: Small cohort with heterogeneous tumors and a short follow-up duration. CONCLUSION: A posterior-first, then anterior 2-stage approach has allowed us to achieve consistent R0 resection margins in locally advanced primary and recurrent rectal and anal cancers involving the deep pelvic sidewall. Poor wound healing of the posterior gluteal incision is a common complication. See Video Abstract. MEJORANDO LAS TASAS DE RESECCIN R CON UN ABORDAJE DE DOS ETAPAS PRIMERO POSTERIOR PARA LA RESECCIN EN BLOQUE DE CNCERES ANORRECTALES PRIMARIOS Y RECURRENTES LOCALMENTE AVANZADOS QUE AFECTAN LA PARED LATERAL PLVICA PROFUNDA: ANTECEDENTES:Utilizando abordajes anteriores estándares, la resección R0 consistente del cáncer de recto y ano primario y recurrente localmente avanzado involucrando la pared lateral pélvica profunda puede ser inalcanzable. Por lo tanto, para mejorar las tasas de resección R0, hemos empleado un abordaje de 2 etapas primero posterior y luego anterior para la resección de tumores en esta ubicación.OBJETIVO:Este estudio tuvo como objetivo evaluar la tasa de resección R0 y los resultados quirúrgicos de los primeros 10 pacientes operados con este abordaje.DISEÑO:Realizamos una revisión retrospectiva de series de casos de nuestros registros de patología quirúrgica y tumores mantenidos prospectivamente.AJUSTE:Este estudio se realizó en la Clínica Mayo en Rochester, Minnesota, EE. UU.PACIENTES:Se identificaron diez pacientes (6 mujeres, mediana de edad 53.5 años) con cáncer anal o rectal primario o recurrente tratados con un abordaje de dos etapas, primero posterior y luego anterior.PRINCIPALES MEDIDAS DE RESULTADO:Las medidas de resultado primarias fueron la tasa de resección R0 y los resultados quirúrgicos.RESULTADOS:Se logró una resección R0 en los 10 pacientes. Nueve pacientes desarrollaron una o más complicaciones de grado III de Clavien-Dindo a los 30 días. Nueve pacientes desarrollaron complicaciones de la herida del glúteo que variaron desde dehiscencia superficial de la herida hasta necrosis del colgajo. Durante el período de seguimiento, se encontró que 4 pacientes tenían enfermedad metastásica y un paciente tuvo recurrencia local.LIMITACIONES:Cohorte pequeño con tumores heterogéneos y corta duración de seguimiento.CONCLUSIÓN:Un abordaje en 2 etapas, primero posterior y luego anterior, nos ha permitido lograr márgenes de resección R0 consistentes en cánceres de recto y anal primarios y recurrentes localmente avanzados que afectan la pared lateral pélvica profunda. La mala cicatrización de la incisión glútea posterior es una complicación común. (Traducción-Dr. Aurian Garcia Gonzalez).


Asunto(s)
Neoplasias del Ano , Neoplasias Gastrointestinales , Neoplasias del Recto , Humanos , Femenino , Persona de Mediana Edad , Neoplasias del Ano/cirugía , Estudios Retrospectivos , Neoplasias del Recto/cirugía , Recurrencia Local de Neoplasia/epidemiología , Complicaciones Posoperatorias , Necrosis
6.
J Cardiovasc Pharmacol ; 83(4): 317-329, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38207007

RESUMEN

ABSTRACT: Chronic stress induces a group of unrecognized cardiovascular impairments, including elevated hemodynamic variables and vascular dysfunction. Moreover, hydrogen sulfide (H 2 S), a gasotransmitter that regulates the cardiovascular system decreases under chronic stress. Thus, this study assessed the impact of sodium hydrosulfide (NaHS) (H 2 S donor) on chronic restraint stress (CRS)-induced cardiovascular changes. For that purpose, male Wistar rats were restrained for 2 hours a day in a transparent acrylic tube over 8 weeks. Then, body weight, relative adrenal gland weight, serum corticosterone, H 2 S-synthesizing enzymes, endothelial nitric oxide synthetize expression, reactive oxygen species levels, lipid peroxidation, and reduced glutathione-to-oxidized glutathione (GSH 2 :GSSG) ratio were determined in the thoracic aorta. The hemodynamic variables were measured in vivo by the plethysmograph method. The vascular function was evaluated in vitro as vasorelaxant responses induced by carbachol or sodium nitroprusside, and norepinephrine (NE)-mediated vasocontractile responses in the thoracic aorta. CRS increased (1) relative adrenal gland weight; (2) hemodynamic variables; (3) vasoconstrictor responses induced by NE, (4) reactive oxygen species levels, and (5) lipid peroxidation in the thoracic aorta. In addition, CRS decreased (1) body weight; (2) vasorelaxant responses induced by carbachol; (3) GSH content, and (4) GSH 2 :GSSG ratio. Notably, NaHS administration (5.6 mg/kg) restored hemodynamic variables and lipid peroxidation and attenuated the vasoconstrictor responses induced by NE in the thoracic aorta. In addition, NaHS treatment increased relative adrenal gland weight and the GSH 2 :GSSG ratio. Taken together, our results demonstrate that NaHS alleviates CRS-induced hypertension by reducing oxidative stress and restoring vascular function in the thoracic aorta.


Asunto(s)
Sulfuro de Hidrógeno , Sulfuros , Ratas , Animales , Masculino , Especies Reactivas de Oxígeno/metabolismo , Disulfuro de Glutatión/metabolismo , Disulfuro de Glutatión/farmacología , Carbacol/farmacología , Ratas Wistar , Sulfuro de Hidrógeno/metabolismo , Estrés Oxidativo , Vasoconstrictores/farmacología , Vasodilatadores/farmacología , Peso Corporal
7.
J Periodontal Res ; 59(3): 611-621, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38500269

RESUMEN

BACKGROUND AND OBJECTIVE: Forkhead box-O 1 (FOXO1) is a transcription factor actively involved in oral wound healing at the epithelial barrier. However, less is known regarding the role of FOXO1 during the tissue repair response in the connective tissue compartment. This study explored the involvement of FOXO1 in the modulation of fibroblast activity related to wound healing. METHODS: Primary cultures of human gingival fibroblasts were obtained from four healthy young donors. Myofibroblastic differentiation, collagen gel contraction, cell migration, cell spreading, and integrin activation were evaluated in the presence or absence of a FOXO1 inhibitor (AS1842856). Variations in mRNA and proteins of interest were evaluated through qRT-PCR and western blot, respectively. Distribution of actin, α-smooth muscle actin, and ß1 integrin was evaluated using immunofluorescence. FOXO1 and TGF-ß1 expression in gingival wound healing was assessed by immunohistochemistry in gingival wounds performed in C57BL/6 mice. Images were analyzed using ImageJ/Fiji. ANOVA or Kruskal-Wallis test followed by Tukey's or Dunn's post-hoc test was performed. All data are expressed as mean ± SD. p < .05 was considered statistically significant. RESULTS: FOXO1 inhibition caused a decrease in the expression of the myofibroblastic marker α-SMA along with a reduction in fibronectin, type I collagen, TGF-ß1, and ß1 integrin mRNA level. The FOXO1 inhibitor also caused decreases in cell migration, cell spreading, collagen gel contraction, and ß1 integrin activation. FOXO1 and TGF-ß1 were prominently expressed in gingival wounds in fibroblastic cells located at the wound bed. CONCLUSION: The present study indicates that FOXO1 plays an important role in the modulation of several wound-healing functions in gingival fibroblast. Moreover, our findings reveal an important regulatory role for FOXO1 on the differentiation of gingival myofibroblasts, the regulation of cell migration, and collagen contraction, all these functions being critical during tissue repair and fibrosis.


Asunto(s)
Actinas , Movimiento Celular , Fibroblastos , Proteína Forkhead Box O1 , Encía , Cicatrización de Heridas , Humanos , Encía/citología , Encía/metabolismo , Cicatrización de Heridas/fisiología , Fibroblastos/metabolismo , Proteína Forkhead Box O1/metabolismo , Animales , Células Cultivadas , Diferenciación Celular , Ratones Endogámicos C57BL , Factor de Crecimiento Transformador beta1/metabolismo , Ratones , Integrina beta1 , Miofibroblastos , Quinolonas
8.
Childs Nerv Syst ; 40(7): 2033-2042, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38649470

RESUMEN

Pediatric optic pathway/hypothalamic gliomas (OPHG) pose challenges in treatment due to their location and proximity to vital structures. Surgical resection plays a key role in the management of OPHG especially when the tumor exhibits mass effect and causes symptoms. However, data regarding outcomes and complications of surgical resection for OPHG remains heterogenous. The authors performed a systematic review on pediatric OPHG in four databases: PubMed, EMBASE, Cochrane Library, and Google Scholar. We included studies that reported on the visual outcomes and complications of OPHG resection. A meta-analysis was performed and reported per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A total of 26 retrospective studies were included. Seven hundred ninety-seven pediatric patients with OPHG undergoing surgical resection were examined. A diagnosis of NF1 was confirmed in 9.7%. Gross total resection was achieved in 36.7%. Intraorbital optic pathway gliomas showed a significantly higher gross total resection rate compared to those located in the chiasmatic/hypothalamic region (75.8% vs. 9.6%). Postoperatively, visual acuity improved in 24.6%, remained unchanged in 68.2%, and worsened in 18.2%. Complications included hydrocephalus (35.4%), anterior pituitary dysfunction (19.6%), and transient diabetes insipidus (29%). Tumor progression post-resection occurred in 12.8%, through a mean follow-up of 53.5 months. Surgical resection remains an essential strategy for treating symptomatic and large pediatric OPHG and can result in favorable vision outcomes in most patients. Careful patient selection is critical. Patients should be monitored for hydrocephalus development postoperatively and followed up to assess for tumor progression and adjuvant treatment necessity.


Asunto(s)
Neoplasias Hipotalámicas , Complicaciones Posoperatorias , Humanos , Niño , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Neoplasias Hipotalámicas/cirugía , Neoplasias Hipotalámicas/complicaciones , Glioma/cirugía , Glioma/complicaciones , Glioma del Nervio Óptico/cirugía , Procedimientos Neuroquirúrgicos/métodos , Procedimientos Neuroquirúrgicos/efectos adversos , Resultado del Tratamiento , Preescolar
9.
J Invertebr Pathol ; 204: 108093, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38479454

RESUMEN

Fastidious endosymbiotic Rickettsiales-like organisms (RLOs) have been observed in the digestive diverticula of the cultured pleasure oyster (Crassostrea corteziensis) from Nayarit, Mexico since 2007. In a few mollusk species, these bacteria have been associated with mortality events and production losses. The type of relationship between the RLOs and the pleasure oyster is largely unknown and further investigations are needed to determine if these bacteria warrant management concern in C. corteziensis. In this study, the morphological characteristics of the RLOs were studied by histology and SEM, and the taxonomic affiliations of the bacteria were evaluated by 16S rRNA amplicon sequencing. In addition, the prevalence and intensity of the RLOs was recorded from 2007 to 2017 by histology. The RLOs were observed inside circular basophilic cytoplasmic membrane bound vacuoles (MBVs) that had an average length and width of 15.70 ± 15.24 µm and 15.42 ± 14.95 µm respectively. Apart from cellular hypertrophy, no tissue alterations were observed in the areas adjacent to the RLOs. Individual bacteria within the MBVs were coccoid in shape with an average length of 0.65 ± 0.12 µm and an average width of 0.38 ± 0.09 µm. The bacterial microbiota of a selected number of samples (one sample without RLOs and two samples with RLOs) showed the presence of intracellular parasite OTUs corresponding to the families Rickettsiaceae and Anaplasmataceae, suggesting that the RLOs from the pleasure oyster is associated with the order Rickettsiales. A mean prevalence of 5 % was observed throughout the study period and the majority of the organisms (89 %) presented low intensity of Grade 1 (30-61 RLOs) of the MBVs. A higher prevalence of the RLOs was observed during warmer months. The lack of tissue alterations, the low prevalence and the low intensity of the MBVs suggest that the RLOs from C. corteziensis is a commensal endosymbiont that presents little risk for oyster production in Nayarit, México. However, regular monitoring is needed to detect if any variation in this relationship occurs, mainly in a scenario where extreme environmental fluctuations may occur.


Asunto(s)
Crassostrea , Rickettsiales , Animales , Crassostrea/microbiología , México , Rickettsiales/fisiología , Acuicultura , Simbiosis , ARN Ribosómico 16S/análisis
10.
Curr Heart Fail Rep ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38958891

RESUMEN

PURPOSE OF REVIEW: Heart failure (HF) represents a pathology in constant growth, but, despite the fact that a significant proportion of its population is comprised of elderly patients, they are not adequately represented in clinical trials or registries. They constitute a heterogeneous population with their particularities and interaction of the multiple comorbidities that characterize this age group, which makes the clinical course, prognosis and outcomes of the disease different. RECENT FINDINGS: Compared to men, women with HF tend to be older, with a greater burden of non-cardiovascular comorbidities, less ischemic heart disease and preserved ventricular function in most cases. This fact translates into worse self-perceived quality of life, with lower hospitalization and mortality rates. Moreover, paradoxically, women are less likely to receive treatment recommended by clinical practice guidelines, including revascularization and device placement. As there are not enough representative studies of this population, the reasons for these results with better prognosis and relatively benign impact in the elderly female population are unknown, which is why it is necessary to continue with research in order to obtain greater evidence of the exposed gaps.

11.
J Acoust Soc Am ; 155(4): 2314-2326, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557736

RESUMEN

Sound zones are used to reproduce individual audio content to multiple people in a room using a set of loudspeakers with controllable input signals. To allow the reproduction of individual audio to dynamically change, e.g., due to moving listeners, changes in the number of listeners, or changing room transfer functions, an adaptive formulation is proposed. This formulation is based on frequency domain block adaptive filters and given room transfer functions. To reduce computational complexity, the system is extended to subband processing without cross-adaptive filters. The computational savings come from recognizing that sound zones consist of part-solutions which are inherently band limited, hence, several subbands can be ignored. To validate the theoretical findings, a 27-channel loudspeaker array was constructed, and measurements were performed in anechoic and reflective environments. The results show that the subband solution performs identically to a full-rate solution but at a reduced computational complexity.

12.
Sensors (Basel) ; 24(5)2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38474940

RESUMEN

The effects of the use of reduced feedback frequencies on motor learning remain controversial in the scientific literature. At present, there is still controversy about the guidance hypothesis, with some works supporting it and others contradicting it. To shed light on this topic, an experiment was conducted with four groups, each with different feedback frequencies (0%, 33%, 67%, and 100%), which were evaluated three times (pre-test, post-test, and retention) during a postural control task. In addition, we tested whether there was a transfer in performance to another similar task involving postural control. As a result, only the 67% feedback group showed an improvement in their task performance in the post-test and retention evaluations. Nevertheless, neither group showed differences in motor transfer performance compared to another postural control task. In conclusion, the findings of this paper corroborate the hypothesis of guidance and suggest that the use of a reduced frequency of 67% is a better option for improving motor learning than options that offer feedback at a lower frequency, at all trials or not at all.


Asunto(s)
Aprendizaje , Equilibrio Postural , Humanos , Adulto Joven , Retroalimentación , Análisis y Desempeño de Tareas , Análisis de Varianza , Destreza Motora
13.
Aesthet Surg J ; 44(6): 612-622, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38284419

RESUMEN

The most common reconstruction technique following mastectomy is a 2-stage technique that involves tissue expansion followed by definitive implant-based reconstruction (IBR). Tissue expanders (TEs) have classically used saline for initial fill; however, TEs with an initial gas fill (GTE)-including the CO2-based AeroForm (AirXpanders, San Francisco, CA) TE and TEs initially filled with atmospheric air-have been increasingly used in the past decade. We aimed to compare the outcomes in breast reconstruction for tissue expanders initially filled with saline vs gas. PubMed was queried for studies comparing gas- and saline-filled tissue expanders (STEs) used in IBR. A meta-analysis was performed on major postoperative outcomes and the required expansion and definitive reconstruction time. Eleven studies were selected and included in the analysis. No significant differences existed between tissue expansion with GTEs vs STEs for 11 of the 13 postoperative outcomes investigated. Out of the complications investigated, only the risk of infection/cellulitis/abscess formation was significantly lower in the GTE cohort (odds ratio 0.62; 95% CI, 0.47 to 0.82; P = .0009). The time to definitive reconstruction was also significantly lower in the GTE cohort (mean difference [MD], 45.85 days; 95% CI, -57.80 to -33.90; P < .00001). The total time to full expansion approached significance in the GTE cohort (MD, -20.33 days; 95% CI, -41.71 to 1.04; P = .06). A cost analysis considering TE cost and infection risk determined that GTE use saved a predicted $2055.34 in overall healthcare costs. Surgical outcomes for both fill types were predominantly similar; however, GTEs were associated with a significantly decreased risk of postoperative infection compared to saline-filled TEs. GTEs could also reduce healthcare expenditures and require less time until definitive reconstruction after placement.


Asunto(s)
Mastectomía , Dispositivos de Expansión Tisular , Expansión de Tejido , Humanos , Dispositivos de Expansión Tisular/efectos adversos , Femenino , Mastectomía/efectos adversos , Mastectomía/métodos , Expansión de Tejido/métodos , Expansión de Tejido/instrumentación , Expansión de Tejido/efectos adversos , Solución Salina/administración & dosificación , Mamoplastia/métodos , Mamoplastia/efectos adversos , Mamoplastia/economía , Resultado del Tratamiento , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/epidemiología , Implantación de Mama/métodos , Implantación de Mama/efectos adversos , Implantación de Mama/instrumentación , Neoplasias de la Mama/cirugía , Implantes de Mama/efectos adversos
14.
Aesthet Surg J ; 44(4): 383-393, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-37757895

RESUMEN

BACKGROUND: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a type of non-Hodgkin lymphoma first linked with breast implants in 2011. The correlation between BIA-ALCL and textured devices has led to increased use of smooth devices. However, much of the data surrounding smooth and textured devices investigates breast implants specifically and not tissue expanders. OBJECTIVES: We performed a systematic review and a meta-analysis to compare surgical outcomes for smooth tissue expanders (STEs) and textured tissue expanders (TTEs). METHODS: A search was performed on PubMed, including articles from 2016 to 2023 (n = 419). Studies comparing TTEs and STEs and reported complications were included. A random-effects model was utilized for meta-analysis. RESULTS: A total of 5 articles met inclusion criteria, representing 1709 patients in the STE cohort and 1716 patients in the TTE cohort. The mean duration of tissue expansion with STEs was 221.25 days, while TTEs had a mean time of tissue expansion of 220.43 days.Our meta-analysis found no differences in all surgical outcomes except for explantation risk. STE use was associated with increased odds of explantation by over 50% compared to TTE use (odds ratio = 1.53; 95% CI = 1.15 to 2.02; P = .003). CONCLUSIONS: Overall, STEs and TTEs had similar complication profiles. However, STEs had 1.5 times higher odds of explantation. The incidence of BIA-ALCL is low, and only a single case of BIA-ALCL has been reported with TTEs. This indicates that TTEs are safe and may lower the risk of early complications requiring explantation. Further studies are warranted to further define the relationship between tissue expanders and BIA-ALCL.


Asunto(s)
Implantación de Mama , Implantes de Mama , Neoplasias de la Mama , Linfoma Anaplásico de Células Grandes , Humanos , Femenino , Dispositivos de Expansión Tisular/efectos adversos , Implantes de Mama/efectos adversos , Implantación de Mama/efectos adversos , Mama/cirugía , Incidencia , Linfoma Anaplásico de Células Grandes/epidemiología , Linfoma Anaplásico de Células Grandes/etiología , Linfoma Anaplásico de Células Grandes/patología , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Neoplasias de la Mama/cirugía
15.
Environ Monit Assess ; 196(2): 198, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38265731

RESUMEN

Characteristics of an acid soil cultivated with Urochloa brizantha cv. Marandu were evaluated in relation to two types of fertilization: a conventional one, chemical based on nitrogen and potassium, and a biofertilizer, based on microalgae biomass. The results were compared among three treatments, control, conventional, and biological fertilization, with seven replications each. The study evaluated microalgae community, total carbon and nitrogen contents, mineral nitrogen, and enzymatic activity. Chlorella vulgaris showed the highest organism density, which can be explained by its rapid growth and high resistance. The highest species diversity was detected in the control 1,380,938 org cm-3 and biological 1,841,250 org cm-3 treatments, with the latter showing a higher density of cyanobacteria, especially Pseudanabaena limnetica with 394,554 org cm-3. The soil treated with chemical fertilization showed higher nitrate (9.14 mg NKg-1 NO3--N) and potassium (52.32 mg dm-3) contents. The highest levels of sulfur (21.73 mg dm-3) and iron (96.46 mgdm-3) were detected in the biological treatment. The chemical treatment showed higher activity of the enzymes acid phosphatase, acetylglucosaminidase, and sulfatase, while α-glucosidase and leucine aminopeptidase stood out in the biological treatment. Soil properties were not significantly affected by the treatments. The use of microalgae biomass derived from wastewater treatment from milking parlors was evaluated and presented as a promising biofertilizer for agriculture, following the line of recovering nutrient-rich wastes. In this sense, although many challenges need to be overcome, the results suggest that microalgal-based fertilizers could lead to low-impact agriculture.


Asunto(s)
Chlorella vulgaris , Microalgas , Suelo , Biomasa , Monitoreo del Ambiente , Fertilidad , Nitrógeno , Potasio
16.
Angew Chem Int Ed Engl ; 63(25): e202405047, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38520388

RESUMEN

Although sulfurated polymers promise unique properties, their controlled synthesis, particularly when it comes to complex and functional architectures, remains challenging. Here, we show that the copolymerization of oxetane and phenyl isothiocyanate selectively yields polythioimidocarbonates as a new class of sulfur containing polymers, with narrow molecular weight distributions (Mn=5-80 kg/mol with D≤1.2; Mn,max=124 kg/mol) and high melting points of up to 181 °C. The method tolerates different substituent patterns on both the oxetane and the isothiocyanate. Self-nucleation experiments reveal that π-stacking of phenyl substituents, the presence of unsubstituted polymer backbones, and the kinetically controlled linkage selectivity are key factors in maximising melting points. The increased tolerance to macro-chain transfer agents and the controlled propagation allows the synthesis of double crystalline and amphiphilic diblock copolymers, which can be assembled into micellar- and worm-like structures with amorphous cores in water. In contrast, crystallization driven self-assembly in ethanol gives cylindrical micelles or platelets.

17.
J Neurosci ; 42(22): 4517-4537, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35477906

RESUMEN

In humans, sleep spindles are 10- to 16-Hz oscillations lasting approximately 0.5-2 s. Spindles, along with cortical slow oscillations, may facilitate memory consolidation by enabling synaptic plasticity. Early recordings of spindles at the scalp found anterior channels had overall slower frequency than central-posterior channels. This robust, topographical finding led to dichotomizing spindles as "slow" versus "fast," modeled as two distinct spindle generators in frontal versus posterior cortex. Using a large dataset of intracranial stereoelectroencephalographic (sEEG) recordings from 20 patients (13 female, 7 male) and 365 bipolar recordings, we show that the difference in spindle frequency between frontal and parietal channels is comparable to the variability in spindle frequency within the course of individual spindles, across different spindles recorded by a given site, and across sites within a given region. Thus, fast and slow spindles only capture average differences that obscure a much larger underlying overlap in frequency. Furthermore, differences in mean frequency are only one of several ways that spindles differ. For example, compared with parietal, frontal spindles are smaller, tend to occur after parietal when both are engaged, and show a larger decrease in frequency within-spindles. However, frontal and parietal spindles are similar in being longer, less variable, and more widespread than occipital, temporal, and Rolandic spindles. These characteristics are accentuated in spindles which are highly phase-locked to posterior hippocampal spindles. We propose that rather than a strict parietal-fast/frontal-slow dichotomy, spindles differ continuously and quasi-independently in multiple dimensions, with variability due about equally to within-spindle, within-region, and between-region factors.SIGNIFICANCE STATEMENT Sleep spindles are 10- to 16-Hz neural oscillations generated by cortico-thalamic circuits that promote memory consolidation. Spindles are often dichotomized into slow-anterior and fast-posterior categories for cognitive and clinical studies. Here, we show that the anterior-posterior difference in spindle frequency is comparable to that observed between different cycles of individual spindles, between spindles from a given site, or from different sites within a region. Further, we show that spindles vary on other dimensions such as duration, amplitude, spread, primacy and consistency, and that these multiple dimensions vary continuously and largely independently across cortical regions. These findings suggest that multiple continuous variables rather than a strict frequency dichotomy may be more useful biomarkers for memory consolidation or psychiatric disorders.


Asunto(s)
Electroencefalografía , Consolidación de la Memoria , Femenino , Hipocampo , Humanos , Masculino , Sueño , Fases del Sueño
18.
J Neurosci ; 42(42): 7931-7946, 2022 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-36041852

RESUMEN

Hippocampal ripples index the reconstruction of spatiotemporal neuronal firing patterns essential for the consolidation of memories in the cortex during non-rapid eye movement sleep (NREM). Recently, cortical ripples in humans have been shown to enfold the replay of neuron firing patterns during cued recall. Here, using intracranial recordings from 18 patients (12 female), we show that cortical ripples also occur during NREM in humans, with similar density, oscillation frequency (∼90 Hz), duration, and amplitude to waking. Ripples occurred in all cortical regions with similar characteristics, unrelated to putative hippocampal connectivity, and were less dense and robust in higher association areas. Putative pyramidal and interneuron spiking phase-locked to cortical ripples during NREM, with phase delays consistent with ripple generation through pyramidal-interneuron feedback. Cortical ripples were smaller in amplitude than hippocampal ripples but were similar in density, frequency, and duration. Cortical ripples during NREM typically occurred just before the upstate peak, often during spindles. Upstates and spindles have previously been associated with memory consolidation, and we found that cortical ripples grouped cofiring between units within the window of spike timing-dependent plasticity. Thus, human NREM cortical ripples are as follows: ubiquitous and stereotyped with a tightly focused oscillation frequency; similar to hippocampal ripples; associated with upstates and spindles; and associated with unit cofiring. These properties are consistent with cortical ripples possibly contributing to memory consolidation and other functions during NREM in humans.SIGNIFICANCE STATEMENT In rodents, hippocampal ripples organize replay during sleep to promote memory consolidation in the cortex, where ripples also occur. However, evidence for cortical ripples in human sleep is limited, and their anatomic distribution and physiological properties are unexplored. Here, using human intracranial recordings, we demonstrate that ripples occur throughout the cortex during waking and sleep with highly stereotyped characteristics. During sleep, cortical ripples tend to occur during spindles on the down-to-upstate transition, and thus participate in a sequence of sleep waves that is important for consolidation. Furthermore, cortical ripples organize single-unit spiking with timing optimal to facilitate plasticity. Therefore, cortical ripples in humans possess essential physiological properties to support memory and other cognitive functions.


Asunto(s)
Consolidación de la Memoria , Sueño de Onda Lenta , Humanos , Femenino , Consolidación de la Memoria/fisiología , Hipocampo/fisiología , Sueño/fisiología , Recuerdo Mental , Electroencefalografía
19.
Ann Neurol ; 92(4): 663-669, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35713346

RESUMEN

We determined the incidence of post-traumatic epilepsy after severe traumatic brain injury. Of 392 patients surviving to discharge, cumulative incidence of post-traumatic epilepsy was 25% at 5 years and 32% at 15 years, an increase compared with historical reports. Among patients with one late seizure (>7 days post-trauma), the risk of seizure recurrence was 62% after 1 year and 82% at 10 years. Competing hazards regression identified age, decompressive hemicraniectomy, and intracranial infection as independent predictors of post-traumatic epilepsy. Patients with severe traumatic brain injury and a single late post-traumatic seizure will likely require long-term antiseizure medicines. ANN NEUROL 2022;92:663-669.


Asunto(s)
Lesiones Traumáticas del Encéfalo , Epilepsia Postraumática , Epilepsia , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/epidemiología , Epilepsia/epidemiología , Epilepsia/etiología , Epilepsia Postraumática/epidemiología , Epilepsia Postraumática/etiología , Humanos , Incidencia , Factores de Riesgo , Convulsiones/complicaciones
20.
Epilepsia ; 64(11): 2993-3012, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37545378

RESUMEN

OBJECTIVE: We aimed to study the correlation between seizure outcomes in patients with drug-resistant epilepsy (DRE) who underwent laser interstitial thermal therapy (LITT) and stereoelectroencephalographic electrophysiologic patterns with respect to the extent of laser ablation. METHODS: We retrospectively analyzed 16 consecutive DRE patients who underwent LITT. A seizure onset zone (SOZ) was obtained from multidisciplinary patient management conferences and again was confirmed independently by two epileptologists based on conventional analysis. SOZs were retrospectively divided into localized, lobar and multilobar, and nonlocalized onset types. A posteriori-predicted epileptogenic zone (PEZ) was identified using the previously developed "EZ fingerprint" pipeline. The completeness of the SOZ and PEZ ablation was compared and correlated with the duration of seizure freedom (SF). RESULTS: Of 16 patients, 11 had an a posteriori-identified PEZ. Three patients underwent complete ablation of SOZ with curative intent, and the other 13 with palliative intent. Of three patients with complete ablation of the SOZ, two had concordant PEZ and SOZ and achieved 40- and 46-month SF without seizure recurrence. The remaining patient, without any PEZ identified, had seizure recurrence within 1 month. Six of 13 patients with partial ablation of the SOZ and PEZ achieved mean seizure freedom of 19.8 months (range = 1-44) with subsequent seizure recurrence. The remaining seven patients had partial ablation of the SOZ without the PEZ identified or ablation outside the PEZ with seizure recurrence within 1-2 months, except one patient who had 40-month seizure freedom after ablation of periventricular heterotopia. SIGNIFICANCE: Only complete ablation of the well-restricted SOZ concordant with the PEZ was associated with long-term SF, whereas partial ablation of the PEZ might lead to SF with eventual seizure recurrence. Failure to identify PEZ and ablation limited to the SOZ often led to 1-2 months of SF.


Asunto(s)
Epilepsia Refractaria , Epilepsia , Terapia por Láser , Neocórtex , Humanos , Neocórtex/cirugía , Estudios Retrospectivos , Epilepsia/cirugía , Convulsiones , Epilepsia Refractaria/cirugía , Electroencefalografía/métodos , Resultado del Tratamiento , Imagen por Resonancia Magnética
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