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1.
ACS Omega ; 9(9): 10080-10089, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38463326

RESUMEN

Carbon-based supercapacitor electrodes are generally restricted in energy density, as they rely exclusively on electric double-layer capacitance (EDLC). The introduction of redox-active organic molecules to obtain pseudocapacitance is a promising route to develop electrode materials with improved energy densities. In this work, we develop a porous nitrogen-doped reduced graphene oxide and 9,10-phenanthrenequinone composite (N-HtrGO/PQ) via a facile one-step physical adsorption method. The electrochemical evaluation of N-HtrGO/PQ using cyclic voltammetry showed a high capacitance of 605 F g-1 in 1 M H2SO4 when the composite consisted of 30% 9,10-phenanthrenequinone and 70% N-HtrGO. The measured capacitance significantly exceeded pure N-HtrGO without the addition of redox-active molecules (257 F g-1). In addition to promising capacitance, the N-HtrGO/30PQ composite showed a capacitance retention of 94.9% following 20,000 charge/discharge cycles. Based on Fourier transform infrared spectroscopy, we postulate that the strong π-π interaction between PQ molecules and the N-HtrGO substrate enhances the specific capacitance of the composite by shortening pathways for electron transfer while improving structural stability.

2.
Mol Biol Cell ; 35(5): ar67, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38507236

RESUMEN

During neuronal development, dynamic filopodia emerge from dendrites and mature into functional dendritic spines during synaptogenesis. Dendritic filopodia and spines respond to extracellular cues, influencing dendritic spine shape and size as well as synaptic function. Previously, the E3 ubiquitin ligase TRIM9 was shown to regulate filopodia in early stages of neuronal development, including netrin-1-dependent axon guidance and branching. Here, we demonstrate that TRIM9 also localizes to dendritic filopodia and spines of murine cortical and hippocampal neurons during synaptogenesis and is required for synaptic responses to netrin. In particular, TRIM9 is enriched in the postsynaptic density (PSD) within dendritic spines and loss of Trim9 alters the PSD proteome, including the actin cytoskeleton landscape. While netrin exposure induces accumulation of the Arp2/3 complex and filamentous actin in dendritic spine heads, this response is disrupted by genetic deletion of Trim9. In addition, we document changes in the synaptic receptors associated with loss of Trim9. These defects converge on a loss of netrin-dependent increases in neuronal firing rates, indicating TRIM9 is required downstream of synaptic netrin-1 signaling. We propose that TRIM9 regulates cytoskeletal dynamics in dendritic spines and is required for the proper response to synaptic stimuli.


Asunto(s)
Actinas , Ubiquitina-Proteína Ligasas , Ratones , Animales , Actinas/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Netrina-1 , Neuronas/metabolismo , Hipocampo/metabolismo , Espinas Dendríticas/metabolismo , Proteínas del Tejido Nervioso/metabolismo
3.
bioRxiv ; 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38260647

RESUMEN

During neuronal development, dynamic filopodia emerge from dendrites and mature into functional dendritic spines during synaptogenesis. Dendritic filopodia and spines respond to extracellular cues, influencing dendritic spine shape and size as well as synaptic function. Previously, the E3 ubiquitin ligase TRIM9 was shown to regulate filopodia in early stages of neuronal development, including netrin-1 dependent axon guidance and branching. Here we demonstrate TRIM9 also localizes to dendritic filopodia and spines of murine cortical and hippocampal neurons during synaptogenesis and is required for synaptic responses to netrin. In particular, TRIM9 is enriched in the post-synaptic density (PSD) within dendritic spines and loss of Trim9 alters the PSD proteome, including the actin cytoskeleton landscape. While netrin exposure induces accumulation of the Arp2/3 complex and filamentous actin in dendritic spine heads, this response is disrupted by genetic deletion of Trim9. In addition, we document changes in the synaptic receptors associated with loss of Trim9. These defects converge on a loss of netrin-dependent increases in neuronal firing rates, indicating TRIM9 is required downstream of synaptic netrin-1 signaling. We propose TRIM9 regulates cytoskeletal dynamics in dendritic spines and is required for the proper response to synaptic stimuli.

4.
J Dent Educ ; 80(9): 1140-8, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27587581

RESUMEN

Dental students require a basic ability to explain and apply general principles of pathology to systemic, dental, and oral pathology. Although there have been recent advances in electronic and online resources, the academic effectiveness of using self-directed e-learning tools in pathology courses for dental students is unclear. The aim of this study was to determine if blended learning combining e-learning with traditional learning methods of lectures and tutorials would improve students' scores and satisfaction over those who experienced traditional learning alone. Two consecutive cohorts of Bachelor of Dentistry and Oral Health students taking the general pathology course at Griffith University in Australia were compared. The control cohort experienced traditional methods only, while members of the study cohort were also offered self-directed learning materials including online resources and online microscopy classes. Final assessments for the course were used to compare the differences in effectiveness of the intervention, and students' satisfaction with the teaching format was evaluated using questionnaires. On the final course assessments, students in the study cohort had significantly higher scores than students in the control cohort (p<0.01). Analysis of questionnaire results showed improved student satisfaction with the course in the study cohort. These findings suggest that the use of e-learning tools such as virtual microscopy and interactive online resources for delivering pathology instruction can be an effective supplement for developing dental students' competence, confidence, and satisfaction.


Asunto(s)
Educación en Odontología/métodos , Educación a Distancia/métodos , Patología Bucal/educación , Humanos , Evaluación de Programas y Proyectos de Salud , Estudiantes de Odontología , Enseñanza
5.
BMC Med Educ ; 16: 46, 2016 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-26842495

RESUMEN

BACKGROUND: The ability to interpret an X-Ray is a vital skill for graduating medical students which guides clinicians towards accurate diagnosis and treatment of the patient. However, research has suggested that radiological interpretation skills are less than satisfactory in not only medical students, but also in residents and consultants. METHODS: This study investigated the effectiveness of e-learning for the development of X-ray interpretation skills in pre-clinical medical students. Competencies in clinical X-Ray interpretation were assessed by comparison of pre- and post-intervention scores and one year follow up assessment, where the e-learning course was the 'intervention'. RESULTS: Our results demonstrate improved knowledge and skills in X-ray interpretation in students. Assessment of the post training students showed significantly higher scores than the scores of control group of students undertaking the same assessment at the same time. CONCLUSIONS: The development of the Internet and advances in multimedia technologies has paved the way for computer-assisted education. As more rural clinical schools are established the electronic delivery of radiology teaching through websites will become a necessity. The use of e-learning to deliver radiology tuition to medical students represents an exciting alternative and is an effective method of developing competency in radiological interpretation for medical students.


Asunto(s)
Competencia Clínica/normas , Educación Médica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiología/educación , Estudiantes de Medicina , Análisis de Varianza , Australia , Humanos , Evaluación de Programas y Proyectos de Salud
7.
Exp Mol Pathol ; 96(2): 212-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24530443

RESUMEN

INTRODUCTION: Galectin family members have been demonstrated to be abnormally expressed in cancer at the protein and mRNA level. This study investigated the levels of galectin proteins and mRNA expression in a large cohort of patients with papillary thyroid carcinoma and matched lymph node metastases with particular emphasis on galectin-1 and galectin-3. METHODS: mRNA expression of galectin family members (1, 2, 3, 4, 7, 8, 9, 10 and 12) were analysed by real-time polymerase chain reaction in 65 papillary thyroid carcinomas, 30 matched lymph nodes with metastatic papillary thyroid carcinoma and 5 non-cancer thyroid tissues. Galectin-1 and 3 protein expression was determined by immunohistochemistry in these samples. RESULTS: Significant expression differences in all tested galectin family members (1, 2, 3, 4, 7, 8, 9, 10 and 12) were noted for mRNA in papillary thyroid carcinomas, with and without lymph node metastasis. Galectin-1 protein was more strongly expressed than galectin-3 protein in papillary thyroid carcinoma. Galectin-1 protein was found to be overexpressed in 32% of primary papillary thyroid carcinomas. A majority of lymph nodes with metastatic papillary thyroid carcinoma (53%) had significantly increased expression of galectin-1 protein, as did 47% of primaries with metastases. Galectin-1 mRNA levels were decreased in the vast majority (94%) of primary thyroid carcinomas that did not have metastases present. Galectin-3 protein levels were noted to be overexpressed in 15% of primary papillary thyroid carcinomas. In primary papillary thyroid carcinoma with lymph node metastases, 32% had over expression of galectin-3 protein. Overexpression of galectin-3 mRNA was noted in 58% of papillary thyroid carcinomas and 64% of lymph nodes bearing metastatic papillary thyroid carcinoma. Also, primary papillary thyroid carcinoma with lymph node metastases had significantly higher expression of galectin-3 mRNA compared to those without lymph node metastases. CONCLUSION: Galectin family members show altered expression at the mRNA level in papillary thyroid cancers. Overexpression of galectin-1 and 3 proteins were noted in papillary thyroid carcinoma with lymph node metastases. The results presented here demonstrated that galectin-1 and galectin-3 expression have important roles in clinical progression of papillary thyroid carcinoma.


Asunto(s)
Carcinoma/genética , Galectina 1/biosíntesis , Galectina 3/biosíntesis , Metástasis Linfática/genética , Neoplasias de la Tiroides/genética , Adulto , Anciano , Carcinoma/patología , Carcinoma Papilar , Femenino , Galectina 1/genética , Galectina 3/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , ARN Mensajero/biosíntesis , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/patología
8.
ANZ J Surg ; 84(6): 406-11, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24456298

RESUMEN

BACKGROUND: There are some concerns that medical student interest in surgery is suffering. The aims of this project were to investigate the proportion of medical students interested in surgery from years 1 to 4, explore influential attitudinal and demographic factors, and establish baseline data to study the future effects of the Surgical Interest Association. METHODS: Students were surveyed through an audience response system in year orientation sessions. For a majority of the analyses, respondents were dichotomized based on expressing an interest in surgery or not. RESULTS: There were no significant differences in the interest students had for a surgical career between medical student year levels in a cross-sectional analysis. However, available longitudinal data demonstrated a significant decrease in surgical interest from first years in 2012 to second years in 2013. Lifestyle, working hours and training length concerns had minimal effects as career influences on students interested in surgery, whereas academic interest and career opportunities were motivating factors in choosing this career. CONCLUSION: The results suggested no difference between levels of interest from first to final year students in surgery as a career, though only 22% of final year students were interested in surgery. This study also suggested that promoting the academic and scientific side of surgery, along with career opportunities available, may be an important avenue to encourage students into surgery. Future research will investigate the changing interests of students in surgery longitudinally throughout the medical school and to analyse the effects of the Surgical Interest Association.


Asunto(s)
Selección de Profesión , Barreras de Comunicación , Cirugía General/estadística & datos numéricos , Estudiantes de Medicina/estadística & datos numéricos , Adulto , Australia , Estudios Transversales , Educación de Pregrado en Medicina/métodos , Femenino , Cirugía General/educación , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto Joven
9.
Behav Brain Res ; 257: 253-64, 2013 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-24103642

RESUMEN

Exposure to sodium valproate (VPA) in utero increases the risk of language impairment and a diagnosis of autism spectrum disorder (ASD). Mice exposed to VPA while in utero have also shown postnatal social deficits. Inhibition of histone deacetylase (HDAC) is one of VPA's many biological effects. The main objective of this study was to test the hypothesis that HDAC inhibition causes these behavioral outcomes following prenatal VPA exposure in mice. We exposed embryonic mice to VPA, the HDAC inhibitor trichostatin A (TSA), or vehicle controls. TSA (1mg/kg) inhibited HDAC in embryonic tissue at a level comparable to 600 mg/kg VPA, resulting in significant increases in histone H3 and H4 acetylation, and histone H3 lysine 4 tri-methylation. Postnatally, decreases in ultrasonic vocalization, olfactory motivation and sociability were observed in TSA and VPA-exposed pups. Treated mice exhibited elevated digging and grooming suggestive of mild restrictive and repetitive behaviors. Olfactory social preference, social novelty and habituation were normal. Together, these data indicate that embryonic HDAC inhibition alone can cause abnormal social behaviors in mice. This result serves as a molecular understanding of infant outcomes following mild VPA exposure in utero.


Asunto(s)
Inhibidores de Histona Desacetilasas/administración & dosificación , Histona Desacetilasas/metabolismo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Efectos Tardíos de la Exposición Prenatal/fisiopatología , Trastorno de la Conducta Social/etiología , Ácido Valproico/administración & dosificación , Animales , Animales Recién Nacidos , Embrión de Mamíferos , Femenino , Ácidos Hidroxámicos/farmacología , Relaciones Interpersonales , Ratones , Ratones Endogámicos C57BL , Actividad Motora/efectos de los fármacos , Embarazo , Prueba de Desempeño de Rotación con Aceleración Constante , Olfato/efectos de los fármacos , Vocalización Animal/efectos de los fármacos
10.
Hum Pathol ; 44(10): 2204-12, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23845470

RESUMEN

Vascular endothelial growth factor (VEGF) promotes growth of blood or lymphatic vessels. The aim of the current study is to identify relationships between VEGF-A and VEGF-C, and their impact in angiogenesis and metastases in thyroid cancers. VEGF-A and VEGF-C mRNA and protein expression was investigated in 136 thyroid cancers (123 papillary thyroid carcinomas and 13 undifferentiated thyroid carcinomas) and 40 matched lymph node metastases with papillary thyroid carcinoma using reverse transcription polymerase chain reaction and immunohistochemistry. VEGF-A and VEGF-C mRNA expression was significantly different between conventional papillary thyroid carcinoma, follicular variant of papillary thyroid carcinoma, and undifferentiated thyroid carcinomas (P = 1 × 10(-6) and 1 × 10(-5), respectively). In undifferentiated carcinoma, VEGF-A and VEGF-C protein overexpression was noted in all cases. VEGF-A and VEGF-C mRNA overexpression was noted in 51% (n = 62) and 27% (n = 33) of the papillary thyroid carcinomas, whereas VEGF-A and VEGF-C protein overexpression was also identified in 70% (n = 86) and 62% (n = 76) of the carcinomas. VEGF-A mRNA was significantly higher in cancers with lymph node metastases compared with nonmetastatic cancers (P = .001), whereas most metastatic cancers underexpressed VEGF-C (P = .0002), with a similar trend for protein. The expression of VEGF-A and VEGF-C correlated with each other at both mRNA and protein levels (P = .00004 and .003, respectively). In summary, VEGF-A and -C expressions correlate with the pathological parameters and metastatic status of thyroid carcinomas. The significant correlations between the expressions of these genes add weight to hypotheses concerning VEGF-A and -C interaction in cancer progression.


Asunto(s)
Adenocarcinoma Folicular/secundario , Carcinoma/secundario , Neovascularización Patológica/patología , Neoplasias de la Tiroides/patología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor C de Crecimiento Endotelial Vascular/metabolismo , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/metabolismo , Adulto , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma Papilar , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/secundario , Factor A de Crecimiento Endotelial Vascular/genética , Factor C de Crecimiento Endotelial Vascular/genética
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