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1.
Neurosurgery ; 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38984821

RESUMEN

BACKGROUND AND OBJECTIVES: Endovascular therapy (EVT) has emerged as the standard for treating patients with acute ischemic stroke due to large vessel occlusion. The aim of this study was to investigate the relationship between early petechial hemorrhage and patient outcomes after successful EVT of anterior circulation. METHODS: We retrospectively analyzed multicenter data from 316 patients who underwent EVT for acute occlusion of anterior circulation. Patients were divided into petechial hemorrhage group and without hemorrhage group based on post-EVT head imaging. Logistical regression analysis was performed to determine independent predictors for petechial hemorrhage, and for petechial hemorrhage as a predictor of early neurological improvement, favorable outcome at 90 days (modified Rankin Scale 0-2), and 90-day mortality, with adjustment for all factors significantly associated with these endpoints in univariate regression to P < .10. RESULTS: Of 316 included patients with successful EVT, 49 (15.50%) had petechial hemorrhage. The petechial hemorrhage group showed less early neurological improvement (36.73% compared with 53.56%, P = .030), less favorable outcomes at 90 days (32.65% compared with 61.80%, P < .001, absolute risk difference 29.15%), and higher mortality at 90 days (28.57% compared with 10.49%, P = .001) then the group without hemorrhage. Petechial hemorrhage was inversely associated with favorable 90-day outcome (odds ratio = 0.415, 95% CI 0.206-0.835) and higher mortality rate at 90 days (odds ratio = 2.537, 95% CI 1.142-5.635) in multivariable regression but was not independently associated with early neurological improvement. CONCLUSION: In patients with anterior large vessel occlusion who underwent successful EVT, petechial hemorrhage was associated with poor functional outcome and 90-day mortality when adjusted for complete recanalization, pre-EVT National Institute of Health Stroke Scale/Score, and Alberta Stroke Program Early Computed Tomography Score. Despite the relatively lower rate of a favorable 90-day outcome with petechial hemorrhage compared with no petechial hemorrhage, the absolute rate of a favorable outcome exceeds the natural history of medical management for this condition.

2.
Food Res Int ; 186: 114348, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38729721

RESUMEN

During production of soy-based infant formula, soy protein undergoes heating processes. This study investigated the differential impact of heating modes on the immunogenic potential of peptides in soy protein digests. Wet or dry heating was applied, followed by in vitro gastrointestinal infant digestion. The released peptides were analyzed by LC-MS/MS. Bioinformatics tools were utilized to predict and identify potential linear B-cell and T-cell epitopes, as well as to explore cross-reactivity with other legumes. Subsequently, the peptide intensities of the same potential epitope across different experimental conditions were compared. As a result, we confirmed the previously observed enhancing effect of wet heating on infant digestion and inhibitory effect of dry heating. A total of 8,546 peptides were detected in the digests, and 6,684 peptides were with a score over 80. Among them, 29 potential T-cell epitopes and 27 potential B-cell epitopes were predicted. Cross-reactivity between soy and other legumes, including peanut, pea, chickpea, lentil, kidney bean, and lupine, was also detected. Overall, heating and digestion time could modulate the potential to trigger peptide-induced immune responses.


Asunto(s)
Digestión , Calor , Péptidos , Proteínas de Soja , Espectrometría de Masas en Tándem , Humanos , Proteínas de Soja/inmunología , Proteínas de Soja/química , Péptidos/inmunología , Péptidos/química , Lactante , Fórmulas Infantiles/química , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito B/inmunología , Reacciones Cruzadas , Calefacción , Cromatografía Liquida
3.
Food Res Int ; 183: 114224, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38760143

RESUMEN

During infant formula production, proteins are always heated, potentially affecting their digestibility and the bioactivities of resulting peptides. Although plant proteins are a promising dairy alternative for infant formula, they remain understudied, necessitating further investigations. Therefore, this research aimed to fill this gap by assessing the impact of different heating modes on soy protein (SP) and pea protein (PP), focusing on glycation levels, peptide formation during in vitro infant digestion, and immune protection potential (sRAGE-binding and antimicrobial activities) of the resulting peptides. Consequently, dry heating led to increased glycation and glycated peptide production, particularly with higher glycation in PP than SP. Moreover, PP exhibited an overall stronger sRAGE-binding capacity than SP, regardless of heating and digestion conditions. Regarding antimicrobial activity, both SP and PP-derived peptides displayed reduced effectiveness against Enterobacter cloacae after dry heating. Additionally, Staphylococcus epidermidis was differently inhibited, where PP-derived peptides showed inherent inhibition. The primary determinant of sRAGE-binding and antimicrobial potential in digestion-derived peptides was the protein source. Subsequent bioinformatics analysis predicted 519 and 133 potential antimicrobial peptides in SP and PP, respectively. This study emphasises the importance of protein source for infant formula to ensure infant health.


Asunto(s)
Digestión , Calor , Fórmulas Infantiles , Proteínas de Guisantes , Proteínas de Soja , Proteínas de Soja/metabolismo , Humanos , Fórmulas Infantiles/química , Lactante , Proteínas de Guisantes/metabolismo , Proteínas de Guisantes/química , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Péptidos Antimicrobianos/metabolismo , Antiinfecciosos/farmacología
4.
Dysphagia ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38558176

RESUMEN

OBJECTIVE: This review evaluates the efficacy and safety of dysphagia interventions for patients with prolonged endotracheal intubation (⩾48 h) in critical care units. DATA SOURCES: We systematically searched PubMed, Cochrane Library, Medline, Embase, OVID, CINAHL, Wanfang (China), CNKI (China), and ProQuest Dissertations for studies published up to December 31, 2023. STUDY SELECTION: Inclusion criteria encompassed randomized controlled trials (RCTs), quasi-randomized trials, and cohort studies comparing dysphagia rehabilitation - such as swallowing stimulation, swallowing and respiratory muscle exercise, and neuromuscular electrical stimulation - with standard care or no treatment. The primary outcomes assessed were dysphagia severity, time to resume oral intake, and incidence of aspiration and aspiration pneumonia. DATA EXTRACTION: Detailed information on study design, setting, participant demographics, interventions, and outcomes was systematically extracted. DATA SYNTHESIS: Our analysis included ten studies with a total of 1031 participants. The findings demonstrate a significant reduction in dysphagia severity, time to oral intake and the risk of aspiration pneumonia, and an improvement in quality of life among patients receiving swallowing therapy. However, no substantial difference was found in nutritional status. Limited data availability necessitated a descriptive presentation of outcomes like the risk of aspiration, ICU/hospital stay duration, pharyngeal/oral residue severity, and intervention-related adverse events. CONCLUSION: The current evidence for the effectiveness of dysphagia interventions in critically ill patients with prolonged endotracheal intubation is limited. There is a pressing need for future research, particularly high-quality RCTs employing standardized outcome measures, to substantiate these findings.

5.
World J Emerg Med ; 14(1): 49-55, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36713334

RESUMEN

BACKGROUND: Swallowing disorder is a common clinical symptom that can lead to a series of complications, including aspiration, aspiration pneumonia, and malnutrition. This study aimed to investigate risk factors of post-extubation dysphagia (PED) in intensive care unit (ICU) patients with endotracheal intubation, and to develop a risk-predictive model for PED, which could serve as an assessment tool for the prevention and control of PED. METHODS: Patients retrospectively selected from June to December 2021 in a tertiary hospital served as the derivation cohort. Patients recruited from the same hospital from March to June 2022 served as the external validation cohort for the predictive model. We used a combination of variable screening and least absolute shrinkage and selection operator (LASSO) regression to select the most useful candidate predictors and checked the multicollinearity of independent variables using the variance inflation factor method. Multivariate logistic regression analysis was performed to calculate the odds ratio (OR; 95% confidence interval [95% CI]) and P-value for each variable to predict diagnosis. The screened risk factors were introduced into R software to build a nomogram model. The performance of the model, including discrimination ability, calibration, and clinical benefit, was evaluated by plotting the receiver operating characteristic (ROC), calibration, and decision curves. RESULTS: A total of 305 patients were included in this study. Among them, 235 patients (53 PED vs. 182 non-PED) were enrolled in the derivation cohort, while 70 patients (17 PED vs. 53 non-PED) were enrolled in the validation cohort. The independent predictors included age, pause of sedatives, level of consciousness, activities of daily living (ADL) score, nasogastric tube, sore throat, and voice disorder. These predictors were used to establish the predictive nomogram model. The model demonstrated good discriminative ability, and the area under the ROC curve (AUC) was 0.945 (95% CI 0.904-0.970). Applying the predictive model to the validation cohort demonstrated good discrimination with an AUC of 0.907 (95% CI 0.831-0.983) and good calibration. The decision-curve analysis of this nomogram showed a net benefit of the model. CONCLUSION: A predictive model that incorporates age, pause of sedatives, level of consciousness, ADL score, nasogastric tube, sore throat, and voice disorder may have the potential to predict PED in ICU patients.

6.
Sci Rep ; 12(1): 20241, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36424507

RESUMEN

Cardiovascular disease (CVD) is the leading cause of global mortality and disease burden. The perceived risk of CVD, a central psychological construct, may affect health behavior change and maintenance, such as lifestyle modification and medication adherence. Risk perception varies based on the knowledge of risk in the context of cultural health-world views. Little is known about CVD-related knowledge and risk perception in China. The aim of this study is to cross-culturally translate, adapt, and evaluate the psychometric properties of the Attitudes and Beliefs about Cardiovascular Disease (ABCD) Risk Perception Questionnaire in Chinese. The translation and cross-cultural adaptation process followed established guidelines. A cross-sectional study of 318 adults between April and May 2022 was conducted in Zhejiang province. The study evaluated the item- and scale-level psychometric properties and validity indices of the ABCD risk perception questionnaire. The exploratory and confirmatory factor analyses of the risk scale supported a three-factor solution that accounts for 69.63% of the total variance, corresponding to risk perception (F1), perceived benefits and intention to change physical activity (F2), and perceived benefits and intention to change dietary habits (F3). Adequate content validity (I-CVI = 0.852-1.00, S-CVI = 946) was ensured by expert panel. The internal consistency of the dimensions showed good results ranging from 0.801 to 0.940 for Cronbach's α, and 0.853 to 0.952 for McDonald's ω. The item analysis of knowledge dimension indicated that the item difficulty index was 0.440 to 0.852, the item discrimination index was 0.572 to 0.707. This study confirmed that the Chinese version of the ABCD risk perception questionnaire has good psychometric properties in terms of measuring CVD-related knowledge and risk perception in the Chinese adult population, which can lead to the development of individually tailored CVD-risk reduction intervention programs or risk communication programs by health providers.


Asunto(s)
Enfermedades Cardiovasculares , Humanos , Psicometría , Estudios Transversales , Costo de Enfermedad , Cumplimiento de la Medicación , Percepción
7.
Org Lett ; 24(19): 3582-3587, 2022 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-35549288

RESUMEN

Indolocarbazole alkaloids and their derivatives were discovered to have potent protein kinase and topoisomerase I inhibitory activities. Disclosed herein is the photochemical synthesis of the indolocarbazole ring system from N-allenyl-2-iodoanilines. The tandem protocol included visible-light-mediated 5-exo-trig radical cyclization and subsequent radical dimerization, followed by acid-promoted deprotection and intramolecular Mannich cyclization. This strategy showed exceptional functional group tolerance and was successfully applied in the concise synthesis of natural products tjipanazoles B and D.


Asunto(s)
Alcadienos , Alcaloides , Alcaloides/química , Ciclización , Dimerización , Estructura Molecular
8.
Intensive Crit Care Nurs ; 70: 103193, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34980516

RESUMEN

BACKGROUND: Guidelines concerning the use of physical restraints in medical facilities have been published and amended over the years. However, the quality and suitability of these guidelines have not been appraised. OBJECTIVES: This study aims to assess the suitability and quality of guidelines for the use of physical restraints in intensive care units with the AGREE-REX and AGREE Ⅱ instruments. METHODS: A systematic search of electronic databases (e.g., EMBASE), cross-database search platforms (e.g., Clinical Key), guideline web portals (e.g., Guidelines International Network) and society websites (e.g., Society of Critical Care Medicine) was conducted from January 2011 to December 2020. The methodological quality was assessed using AGREE Ⅱ, and the recommendation quality and suitability were assessed using AGREE-REX instruments. RESULTS: A total of eight guidelines were included. The criteria for overall quality and suitability of guidelines for the use of physical restraints were met by 50-72% and 59-76%, respectively. The "Values and Preferences" domain had the lowest score (38% ± 9%). The criteria for methodological quality of the guidelines were met by 50-83%. Two domains, "Applicability" and "Editorial Independence", achieved lower scores. There was a strong, positive correlation between the overall methodological quality of guidelines and the overall quality of recommendations (r = 0.968). CONCLUSION: There is a potential feasibility of guideline adaptation for the management of physical restraints. In order to implement a physical restraint guideline, the following aspects should be considered: (i) minimize the use of physical restraints, (ii) analyze barriers and facilitators relative to the local context, (iii) consider any specifications, and (iv) modify recommendations to local situation or individual conditions of the patient.


Asunto(s)
Unidades de Cuidados Intensivos , Restricción Física , Cuidados Críticos , Bases de Datos Factuales , Humanos
9.
Food Chem ; 375: 131878, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34952386

RESUMEN

Soy protein is the main protein source for plant-based infant formula, whereas pea protein is considered as a potential alternative plant protein source. This study assessed the structural changes of soy and pea proteins after heating between 65 °C and 100 °C, and its effects on the in vitro digestibility in the context of infant digestion. We found that with increased heating intensity, both soy and pea proteins unfolded, manifested as the increased surface hydrophobicity, thereby potentially improving the accessibility to digestive enzymes. Their final in vitro digestibility increased from âˆ¼ 30% of non-treated samples to âˆ¼ 60% of 100 °C-heated samples for soy protein, and from âˆ¼ 52% to âˆ¼ 65% for pea protein. Surface hydrophobicity was strongly positively correlated to the overall digestibility. Therefore, the heating temperatures that enabled protein unfolding promoted the digestibility of soy and pea proteins under infant digestion conditions.


Asunto(s)
Proteínas de Guisantes , Proteínas de Plantas , Digestión , Calor , Humanos , Lactante , Proteínas de Soja
10.
Oncol Lett ; 21(3): 210, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33552292

RESUMEN

Long non-coding RNAs (lncRNAs) play an important role in gene regulation. Several lncRNAs have been demonstrated to be associated with the diagnosis and prognosis of non-small cell lung cancer (NSCLC). The present study aimed to investigate the role of lncRNA long intragenic non-protein-coding RNA p53-induced transcript (LINC-PINT) in NSCLC to identify a novel non-invasive biomarker for the diagnosis and prognosis of patients with NSCLC. Reverse transcription-quantitative PCR analysis was performed to detect LINC-PINT expression in the tissue and serum samples of patients with NSCLC. The diagnostic and prognostic values of LINC-PINT were assessed via the receiver operating characteristic curve, and Kaplan-Meier and Cox regression analyses, respectively. The results demonstrated that LINC-PINT expression was significantly downregulated in NSCLC serum samples and tissues. In addition, serum LINC-PINT exhibited diagnostic value in patients with NSCLC, and may be used to predict prognosis. Furthermore, aberrant LINC-PINT expression in tumor tissues was significantly associated with lymph node metastasis, tumor size, differentiation and TNM stage. Taken together, the results of the present study suggest that lncRNA LINC-PINT may be an independent diagnostic and prognostic biomarker in NSCLC.

11.
Chem Sci ; 12(47): 15655-15661, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-35003596

RESUMEN

Thiophenol was discovered to form an EDA complex with iodobenzene through halogen bonding interactions upon treatment with KOH. A direct photochemical thiolation of C(sp3)-H bond-containing etheric, allylic, and benzylic substrates with thiophenol was developed. The reaction proceeded on the basis of the in situ generation of a thiyl radical and aryl radical through single electron transfer between the photoexcited thiophenolate anion and aryl iodide EDA complex. Then a C(sp3) centred-radical was formed by aryl radical-mediated hydrogen atom transfer and the thiolation products were delivered via a radical-radical cross-coupling with the thiyl radical.

12.
Chem Sci ; 12(47): 15770, 2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-35006211

RESUMEN

[This corrects the article DOI: 10.1039/D1SC03667J.].

13.
Oncol Lett ; 21(1): 33, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33262825

RESUMEN

Gastric cancer (GC) is one of the most common malignancies with a high worldwide incidence rate. The association between microRNAs (miRs) and malignancy has been widely studied in recent years. The aim of the present study was to assess the clinical value of miR-4636 in patients with GC and its effect on the proliferation, migration and invasion of GC cells. Reverse transcription-quantitative PCR was used to detect the expression of miR-4636. Receiver operating characteristics curve, Kaplan-Meier survival curve and Cox regression analyses were used to evaluate the diagnostic and prognostic value of miR-4636. Transwell migration and MTT assays were used to assess the regulatory effects of miR-4636 expression on the biological function of GC. The results demonstrated that the expression of miR-4636 was significantly downregulated in GC serum and tissue samples, as well as in GC cell lines. The aberrant miR-4636 expression was closely associated with lymph node metastasis and TNM stage, and had considerable diagnostic and prognostic significance in patients with GC. Cellular experiments revealed that the overexpression of miR-4636 inhibited GC cell proliferation, migration and invasion, while the knockdown of miR-4636 led to opposite effects on the biological function of GC. In summary, decreased miR-4636 expression may serve as a biomarker for the diagnosis and prognosis of GC. Furthermore, miR-4636 overexpression significantly inhibited GC cell proliferation, migration and invasion, indicating the potential of miR-4636 as a therapeutic target for GC treatment.

14.
Onco Targets Ther ; 13: 4229-4237, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32523358

RESUMEN

BACKGROUND: Lung cancer remains the most frequent malignancy worldwide with increasing morbidity and mortality. This study aimed to assess the expression of microRNA-374b-5p (miR-374b-5p) in tissues and cell lines of non-small cell lung cancer (NSCLC) and to evaluate the prognostic value of miR-374b-5p as well as its biological function in tumor progression. MATERIALS AND METHODS: Expression of miR-374b-5p in NSCLC patients and cells was estimated using quantitative real-time PCR. The prognostic value of miR-374b-5p was evaluated using Kaplan-Meier method and Cox regression analysis. Gain-of-function and loss-of-function cell experiments were performed to examine the effects of miR-374b-5p on NSCLC cell proliferation, migration and invasion. A luciferase activity assay was used to confirm the target gene of miR-374b-5p. RESULTS: miR-374b-5p expression levels were decreased in tumorous tissues and cell lines compared with the normal tissues or cells (P < 0.05). The expression of miR-374b-5p was associated with the patients' tumor size, lymph node metastasis and TNM stage (all P < 0.05). Patients with low miR-374b-5p expression have a shorter survival time (log-rank P = 0.001), and the downregulated expression of miR-374b-5p was determined to be an independent prognostic indicator of NSCLC. In NSCLC cells, the overexpression of miR-374b-5p could inhibit NSCLC cell proliferation, migration and invasion and could directly target FOXP1. CONCLUSION: This study found that the decreased miR-374b-5p predicts poor prognosis of NSCLC, and the upregulation of miR-374b-5p can inhibit NSCLC cell proliferation, migration and invasion. The data obtained from this study provide a novel candidate prognostic biomarker and a potential therapeutic target for NSCLC.

15.
J Crit Care ; 56: 249-256, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31986368

RESUMEN

PURPOSE: The aim of this study was to explore the effects of an enteral nutrition (EN) feeding protocol in critically ill patients. METHODS: This was a prospective multi-center before-after study. We compared energy related and prognostic indicators between the control group (pre-implementation stage) and intervention group (post-implementation stage). The primary endpoint was the percentage of patients receiving EN within 7 days after ICU admission. RESULTS: 209 patients in the control group and 230 patients in the intervention group were enrolled. The implementation of the EN protocol increased the percentage of target energy reached from day 3 to day 7, and the difference between two groups reached statistical significance in day 6 (P = .01) and day 7 (P = .002). But it had no effects on proportion of patient receiving EN (P = .65) and start time of EN (P = .90). The protocol application might be associated with better hospital survival (89.1% vs 82.8%, P = .055) and reduce the incidence of EN related adverse (P = .004). There was no difference in ICU length of stay, duration of mechanical ventilation and ICU cost. CONCLUSION: The implementation of the enteral feeding protocol is associated with improved energy intake and a decreased incidence of enteral nutrition related adverse events for critically ill patients, but it had no statistically beneficial effects on reducing the hospital mortality rate. Trial registration ClinicalTrials.gov, NCT02976155. Registered November 29, 2016- Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT02976155.


Asunto(s)
Enfermedad Crítica/mortalidad , Nutrición Enteral/métodos , Unidades de Cuidados Intensivos , Tiempo de Internación , Respiración Artificial/efectos adversos , China , Estudios Controlados Antes y Después , Ingestión de Energía , Femenino , Mortalidad Hospitalaria , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Admisión del Paciente , Pronóstico , Estudios Prospectivos
16.
J Food Sci ; 84(5): 1188-1193, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30942899

RESUMEN

Plant ferritin in holo form is considered as a novel, ideal iron supplement for human nutrition in the 21st century, but its self-degradation and self-association features limit its application on account of the presence of extension peptide (EP), a specific domain only found in plant ferritin. Although reported chemicals such as Phenylmethanesulfonyl fluoride (PMSF) can inhibit its self-degradation, they are not edible and toxic. In the present work, we found that thermal treatment of pea seed ferritin (PSF) in the range of 60 to 80 °C can prolong the storage time of PSF from 3 days to at least 10 days. In the meanwhile, the aggregated form can be inhibited upon such treatment, therefore promoting its monodispersity. More important, such treatment had little effect on the natural shell-like structure of holo PSF and its iron content. In contrast, thermal treatment at higher temperature (90 °C or above) resulted in a change in ferritin structure. These new findings pave the way to the application of plant ferritin as an iron supplement. PRACTICAL APPLICATION: Thermal treatment at 60 to 80 °C can prolong the storage stability of PSF from 3 days to at least 10 days and prevent it from self-aggregation without affecting the shell-like structure. It has been known that the stability of PSF is closely associated with the bioavailability of iron within PSF. From the standpoint of nutrition, the above-mentioned thermal treatment could be used as a cooking method in our daily life or in food industry to improve the bioavailability of ferritin iron, thereby being beneficial for exploration of plant ferritin as a novel, ideal iron supplement to fight against IDA.


Asunto(s)
Proteínas en la Dieta , Ferritinas , Almacenamiento de Alimentos , Pisum sativum , Proteínas de Plantas , Proteínas en la Dieta/química , Proteínas en la Dieta/efectos de la radiación , Ferritinas/química , Ferritinas/efectos de la radiación , Calor , Proteínas de Plantas/química , Proteínas de Plantas/efectos de la radiación , Estabilidad Proteica
17.
PLoS One ; 11(1): e0146017, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26741374

RESUMEN

The lateral geniculate nucleus (LGN) is increasingly regarded as a "smart-gating" operator for processing visual information. Therefore, characterizing the response properties of LGN neurons will enable us to better understand how neurons encode and transfer visual signals. Efforts have been devoted to study its anatomical and functional features, and recent advances have highlighted the existence in rodents of complex features such as direction/orientation selectivity. However, unlike well-researched higher-order mammals such as primates, the full array of response characteristics vis-à-vis its morphological features have remained relatively unexplored in the mouse LGN. To address the issue, we recorded from mouse LGN neurons using multisite-electrode-arrays (MEAs) and analysed their discharge patterns in relation to their location under a series of visual stimulation paradigms. Several response properties paralleled results from earlier studies in the field and these include centre-surround organization, size of receptive field, spontaneous firing rate and linearity of spatial summation. However, our results also revealed "high-pass" and "low-pass" features in the temporal frequency tuning of some cells, and greater average contrast gain than reported by earlier studies. In addition, a small proportion of cells had direction/orientation selectivity. Both "high-pass" and "low-pass" cells, as well as direction and orientation selective cells, were found only in small numbers, supporting the notion that these properties emerge in the cortex. ON- and OFF-cells showed distinct contrast sensitivity and temporal frequency tuning properties, suggesting parallel projections from the retina. Incorporating a novel histological technique, we created a 3-D LGN volume model explicitly capturing the morphological features of mouse LGN and localising individual cells into anterior/middle/posterior LGN. Based on this categorization, we show that the ON/OFF, DS/OS and linear response properties are not regionally restricted. Our study confirms earlier findings of spatial pattern selectivity in the LGN, and builds on it to demonstrate that relatively elaborate features are computed early in the visual pathway.


Asunto(s)
Cuerpos Geniculados/fisiología , Neuronas/fisiología , Corteza Visual/fisiología , Campos Visuales/fisiología , Vías Visuales/fisiología , Animales , Sensibilidad de Contraste/fisiología , Potenciales Evocados Visuales/fisiología , Femenino , Cuerpos Geniculados/anatomía & histología , Ratones , Ratones Endogámicos C57BL , Microelectrodos , Neuronas/citología , Orientación/fisiología , Estimulación Luminosa , Percepción Espacial/fisiología , Técnicas Estereotáxicas , Corteza Visual/anatomía & histología , Vías Visuales/anatomía & histología
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